Kidney failure creates an unusual internal environment. As renal clearance declines, nitrogenous waste accumulates and changes the chemistry of the gut lumen. Protein-bound toxins such as indoxyl sulfate, p-cresyl sulfate and trimethylamine N-oxide can reach concentrations 10 to 50 times those in healthy controls, according to the review. These compounds are not simply passengers carried by the blood. Indoxyl sulfate activates the aryl hydrocarbon receptor and promotes oxidative stress, while microbial metabolism of tryptophan and tyrosine supplies additional precursors for toxin production. The resulting chemical environment favors pathobionts and disadvantages commensal organisms, including short-chain-fatty-acid producers such as Faecalibacterium and Roseburia.

That shift has structural consequences for the intestine. Butyrate normally supplies energy to colon cells and signals through receptors involved in metabolic and immune regulation. As butyrate-producing bacteria decline, epithelial integrity and anti-inflammatory signaling may weaken. Uremic toxins can also disturb tight-junction proteins, including occludin, claudin-1 and zonula occludens-1. The resulting permeability permits lipopolysaccharide and other microbial products to enter the circulation. Studies summarized in the review link this endotoxemia with higher C-reactive protein and interleukin-6, lower residual kidney function and the low-grade inflammation that characterizes maintenance dialysis. Metabolomic studies also report depleted short-chain fatty acids and altered tryptophan and bile-acid pathways, although most comparisons remain observational.

Immune dysfunction follows two apparently contradictory directions. Pattern-recognition receptors including Toll-like receptor 4, NOD2, NLRP3 and RIG-I respond to microbial products by activating nuclear factor-kappa B and mitogen-activated protein kinase signaling, increasing inflammatory cytokines such as interleukin-6, tumor necrosis factor alpha and interleukin-1 beta. At the same time, uremia impairs neutrophil phagocytosis, monocyte oxidative burst, dendritic-cell antigen presentation and aspects of antibody defense. Altered T-cell and monocyte populations, expansion of myeloid-derived suppressor cells and exhausted T-cell markers have also been described. The result is a state resembling “immunological paralysis”: persistent immune activation alongside reduced capacity to contain infection. The cellular evidence is less extensive than the cytokine evidence and still needs systematic characterization in dialysis-specific cohorts.

Nutrition and muscle are woven into the same feedback system. Protein-energy wasting combines loss of muscle and other body stores with inadequate energy availability. The review reports that muscle mass declines two to three times faster in kidney disease than during normal aging and that malnutrition affects an estimated 18% to 75% of dialysis populations, depending on how it is defined. Inflammation can suppress appetite, activate the ubiquitin-proteasome system and alter myostatin, insulin-like growth factor and JAK–STAT signaling. Restrictive diets may reduce potassium and phosphorus but also limit fiber diversity and the substrates required by saccharolytic bacteria. Evidence connecting dysbiosis to sarcopenia is still mainly cross-sectional or mechanistic: it cannot yet establish whether microbial change causes muscle loss, follows malnutrition and inactivity, or shares inflammation as an upstream driver.

Hemodialysis and peritoneal dialysis place different kinds of stress on this network. Hemodialysis produces rapid fluctuations in toxins and fluid, and rapid ultrafiltration can contribute to intradialytic hypotension and myocardial stunning. Blood repeatedly contacts artificial membranes, activating complement and circulating leukocytes. The review reports more pronounced depletion of butyrate-producing organisms, enrichment of Proteobacteria and Fusobacteria, and generally greater endotoxemia. Peritoneal dialysis is continuous and often preserves residual kidney function and hemodynamic stability for longer, but continuous absorption of glucose adds calories and can worsen insulin resistance, dyslipidemia and adiposity. Glucose degradation products and advanced glycation end-products promote peritoneal inflammation, fibrosis, neoangiogenesis and eventual ultrafiltration failure. Its microbial profile includes amplification of Enterobacteriaceae and depletion of Bifidobacterium and Lactobacillus, though the peritoneal literature is smaller and more vulnerable to confounding by diet, shared environments, medications and other illnesses.

Multi-omics methods offer a way to examine these systems together. Metagenomics and metatranscriptomics characterize microbial genes and active pathways, while metabolomics measures circulating and fecal metabolites, and proteomics, lipidomics and single-cell transcriptomics can characterize immune states. Network analysis and supervised machine learning may detect coordinated signatures that single-domain tests miss. One case-control CKD study cited in the review found that gut microbial functional profiles, including carbohydrate-active enzyme genes, predicted early disease more accurately than serum-metabolite or immune-cell models alone and correlated with circulating amino acids and immune-cell clusters. Such findings demonstrate analytical promise, not a validated patient-classification system. The proposed MIN Index would combine 16S sequencing or metagenomics, multiplex immune assays, biochemical measurements, body composition, functional testing and dietary assessment, with modality-specific weights estimated from outcomes such as infection, hospitalization, cardiovascular events, technique failure and mortality.

Developing that framework would require evidence rather than conceptual polish. The authors suggest a derivation cohort of at least 300 to 500 hemodialysis and peritoneal dialysis patients followed for 12 to 24 months, followed by external validation in a separate population. Sampling would need to cover diet, diabetes, residual kidney function, antibiotics, iron, phosphate binders, proton-pump inhibitors and other medications that can alter microbial communities. Because high-dimensional data invite overfitting, weights derived in one cohort would have to be tested without refitting in another. The index would also have to demonstrate added value over cheaper measures such as the Malnutrition–Inflammation Score, albumin or C-reactive protein, using outcomes that patients experience rather than biomarker changes alone. Its inputs would need to be collected within a defined window, and the test–retest stability of repeated microbiome measurements would need to be established because diet, infection and antibiotics can alter gut composition within days.

Therapeutic ideas remain largely ahead of clinical proof. Fiber-rich and plant-based diets may support short-chain-fatty-acid production, but potassium and phosphorus restrictions complicate implementation, especially in regions where vegetarian diets are already common. Probiotic and prebiotic trials have reported modest improvements in toxins, bowel function or inflammatory markers, generally in small cohorts without demonstration of fewer infections, hospitalizations or deaths. Fecal microbiota transplantation improved kidney and inflammatory measures in a rat model and has early human evidence outside dialysis, but transmission risks, donor screening, uncertain durability and the uremic environment complicate use in frail patients. Omega-3 fatty acids and polyphenols may influence inflammatory pathways, but clinical results are inconsistent. Advanced high-volume hemodiafiltration improves middle-molecule clearance and has produced favorable mortality results in one trial, yet its direct effects on the gut axis remain unmeasured. The review consequently supports carefully monitored research rather than routine use of an unvalidated index or unproven microbiome-based treatment.

Closing the gap will depend on larger, more diverse and longer studies. Most available evidence comes from small, single-center or cross-sectional investigations, often in Western populations, while healthcare access, diet, genetics, environmental exposure and medication use differ markedly across regions. Standardized stool collection, sequencing, bioinformatics and metadata reporting are needed so results can be pooled; common repositories and international consortia could make that possible. Longitudinal cohorts beginning before dialysis could establish whether dysbiosis precedes or follows uremia, infection and malnutrition, while randomized trials of combination interventions could test whether altering several linked domains is more effective than targeting one. The central proposal is therefore not that a single score can immediately guide dialysis care, but that dialysis outcomes may become more predictable if researchers model the gut, immune system, nutrition and residual kidney function as the interacting system they are. The MIN Index offers a structured hypothesis for that work, with its clinical value still to be demonstrated.

Subject of Research: Kidney–gut–immune–nutrition interactions and risk stratification in hemodialysis and peritoneal dialysis

Article Title: Beyond solute clearance: the kidney–gut–immune–nutrition axis in hemodialysis and peritoneal dialysis and a proposed framework for integrated risk stratification

Article References: Rawat, A., Prasad, N., Rawat, P., Ahmed, S., Kumar, B., Singh, A., Nayak, T., & Kushwaha, R. S. (2026). Beyond solute clearance: the kidney–gut–immune–nutrition axis in hemodialysis and peritoneal dialysis and a proposed framework for integrated risk stratification. Frontiers in Nutrition, 13, Article 1931760. https://doi.org/10.3389/fnut.2026.1931760

Image Credits: AI Generated

DOI: 10.3389/fnut.2026.1931760

Keywords: dialysis, gut microbiome, uremic toxins, immune dysregulation, protein-energy wasting, multi-omics, hemodialysis, peritoneal dialysis, risk stratification, clinical nutrition, Beyond, solute

The review describes chemotherapy-related fatigue as a multifactorial problem involving chronic inflammation, immune dysregulation, neuroendocrine abnormalities and mitochondrial dysfunction. According to the abstract, inflammation and immune readjustment are identified as primary factors, while high-altitude hypoxia may add to these processes. These mechanisms are presented as contributing factors rather than as results from a new clinical study, and the abstract does not provide study-specific estimates of how high altitude alters fatigue risk or severity.

For nonpharmacological management, the abstract reports evidence that physical activity, cognitive behavioral therapy and mindfulness have been effective in controlling fatigue. It also states that evidence for pharmacological treatment remains inconclusive. The authors emphasize that reversible factors, including anemia and sleep disorders, should be managed. This wording reflects the review’s summary of existing management evidence and does not establish that any intervention is effective specifically for patients living at high altitude.

The review calls for further research into chemotherapy-related fatigue mechanisms in elevated areas and for customized treatments intended to improve patients’ quality of life. That proposal is not a demonstrated outcome: the available evidence describes a review rather than a trial of altitude-specific treatment. The principal limitation is that only abstract-level information was supplied, preventing verification of the included studies, their populations, outcome measures, synthesis methods and certainty of conclusions. The review was published in Supportive Care in Cancer as Volume 34, article 903, on 28 August 2026.

Subject of Research: A review of chemotherapy-related fatigue mechanisms and management in breast cancer patients living at high altitude

Article Title: Recent advances in understanding chemotherapy-induced fatigue in BC patients residing in high-altitude regions: a review

Article References: Wu, T., Li, J., Zhao, F., & Liu, Z. (2026). Recent advances in understanding chemotherapy-induced fatigue in BC patients residing in high-altitude regions: a review. Supportive Care in Cancer, 34(9), Article 903. https://doi.org/10.1007/s00520-026-11151-6

Image Credits: AI Generated

DOI: 10.1007/s00520-026-11151-6

Keywords: breast cancer, chemotherapy-related fatigue, high altitude, hypoxia, inflammation, immune dysregulation, quality of life, nonpharmacological care, supportive care, Recent, advances, understanding

The researchers prospectively enrolled children aged 6 months to 15 years who were admitted to the pediatric burn service at UF Health Shands Children’s Hospital between December 2023 and July 2025. The cohort included 14 children with small burns and nine with moderate burns. Seven healthy controls younger than 16 were undergoing elective pediatric surgery. The investigators collected blood from burn patients on hospital day 2, with a window of one day either side, and obtained later samples when clinically feasible. Control blood was collected in the operating room after induction of anesthesia and before surgery. Because sampling times were partly determined by each child’s clinical course, serial specimens were not available from every participant at every interval, and the number included in each immune assay varied.

Monocyte HLA-DR was measured by flow cytometry in circulating CD14-positive monocytes. The researchers converted median fluorescence intensity into the average number of anti-HLA-DR antibodies bound per cell, a measure reported as ABC. This analysis included seven controls, 11 small-burn patients and six moderate-burn patients. Median HLA-DR expression was significantly lower in the moderate-burn group than in healthy controls, while the small-burn group did not differ significantly from either comparison group after statistical correction for multiple comparisons. The estimated Hodges–Lehmann location shift between the moderate-burn and control groups was minus 22,939 ABC, with an exact 96.50% confidence interval from minus 33,104 to minus 12,039. Individual values varied considerably, including substantial overlap between the small-burn and moderate-burn groups.

The investigators also assessed whether burn injury altered circulating myeloid-derived suppressor cells, or MDSCs, a heterogeneous collection of immature myeloid cells described in the study as having immunosuppressive activity. Flow-cytometric phenotyping of peripheral blood mononuclear cells was performed approximately one week after injury in seven controls, six small-burn patients and six moderate-burn patients. Total MDSCs and three subsets—monocytic, polymorphonuclear and early MDSCs—showed considerable person-to-person variation. Some measures appeared numerically higher in the moderate-burn group, but neither total frequencies, subset frequencies nor absolute subset counts differed significantly among the three groups. Absolute total MDSC counts were numerically higher in moderate-burn patients, with a median of 253,685 compared with 161,336 in controls and 117,892 in the small-burn group, but the difference was not statistically significant.

Functional responsiveness was tested with a whole-blood TNF-α ELISpot assay. Diluted blood was incubated for 24 hours with or without LPS, and spots representing TNF-α-secreting cells were counted and characterized. The day-2 analysis included seven controls, seven small-burn patients and eight moderate-burn patients. LPS increased the number of spots, their size and total expression within every cohort, demonstrating that all three groups retained the capacity to respond to the stimulus. Among stimulated samples, however, the moderate-burn group produced the strongest responses. Stimulated spot-forming units, spot size and total expression were significantly higher than in controls, while total expression was also significantly higher than in the small-burn group. The small-burn cohort did not differ significantly from controls.

The magnitude of the acute functional differences was appreciable. The estimated shift in stimulated spot-forming units between moderate-burn patients and controls was 294, with an exact 95.99% confidence interval of 36 to 506. The corresponding shifts were 1.203 for stimulated spot size, with a confidence interval of 0.3966 to 2.521, and 2,503 for total expression, with a confidence interval of 974.7 to 3,686. Compared with small-burn patients, the estimated difference in total expression was 2,229, with a confidence interval of 403.2 to 3,473. These results indicate that the heightened response was specific to the moderate-burn group in this cohort rather than evidence of a general rise in every burned child.

Exploratory analyses suggested that immune measures might also differ among children with and without inpatient complications, defined in the study as graft loss, wound infection, gastrointestinal infection or bacteremia. Among burn patients with available data, those who experienced complications had larger burns: a median of 25% TBSA, compared with 11% among those without complications. Those with complications also had lower day-2 monocyte HLA-DR expression, with a median of 28,603 ABC versus 40,910 ABC. Whole-blood LPS-induced TNF-α responses did not differ significantly by complication status. These observations were exploratory, and burn size was greater in the complication group, making it difficult to separate the independent effects of severity, clinical interventions and immune markers.

Only three moderate-burn patients provided samples for a descriptive comparison at six to eight weeks after injury. Their later samples showed lower spot-forming units and total TNF-α expression than their acute day-2 samples, while spot size appeared similar. The small and incomplete dataset was not subjected to inferential testing and cannot establish how immune responsiveness changes during recovery. It nevertheless points toward a possible difference between acute and later responses. More broadly, the assays captured different immune domains: monocyte HLA-DR was a cell-specific phenotypic measurement, whereas whole-blood ELISpot responses reflected an integrated cytokine response from multiple blood-cell populations and did not identify the cellular source of TNF-α.

The study has important limitations. It was conducted at a single center with modest, assay-specific sample sizes, making it underpowered for modest differences and limiting generalizability. Nonsignificant results should not be interpreted as proof of equivalence. The cohort was predominantly male, no healthy control was African American, controls underwent diverse elective operations, and burn care—including surgery, transfusion, antibiotics, nutritional support and intensive care—varied with severity. The study was not designed to isolate those interventions’ effects. Burn depth was mixed, longitudinal sampling was incomplete, T-regulatory cells were not measured, and broader cytokine profiling and leukocyte functions such as phagocytosis, reactive oxygen species production and migration were not systematically assessed. All 30 participants were ultimately discharged in stable condition, and the research characterized early immune patterns rather than establishing that any marker predicts infection or other outcomes. Taken together, the results indicate that moderate pediatric burns were associated with concurrent phenotypic and functional innate immune alterations, rather than a uniformly weakened immune response.

Subject of Research: Early innate immune alterations in children with small and moderate burn injuries

Article Title: Moderate pediatric burn injury is associated with reduced monocyte HLA-DR expression and heightened whole-blood LPS-induced TNF-α responses

Article References: Wiggins, W. B., Rincon, J. C., Hernández-Ríos, M., Polcz, V., Rodhouse, C., Yoham, A. L., Richter, S., Cabral, A., Moldawer, L. L., Efron, P. A., Maile, R., & Larson, S. D. (2026). Moderate pediatric burn injury is associated with reduced monocyte HLA-DR expression and heightened whole-blood LPS-induced TNF-α responses. Frontiers in Pediatrics, 14, Article 1967322. https://doi.org/10.3389/fped.2026.1967322

Image Credits: AI Generated

DOI: 10.3389/fped.2026.1967322

Keywords: pediatric burns, innate immunity, monocyte HLA-DR, TNF-alpha, lipopolysaccharide, ELISpot, flow cytometry, myeloid-derived suppressor cells, immune dysregulation, Moderate, pediatric, burn

Onychodystrophy, the descriptive term for abnormal nail structure or growth, is not a diagnosis in itself. It can arise from damage to any component of the nail unit, including the nail matrix where the plate is generated, the nail bed beneath it, the plate itself, or the surrounding nail folds. One characteristic pattern, trachyonychia, produces rough, dull, longitudinally ridged or fissured plates and reflects disrupted keratinization within the matrix. Pediatric nail disorders are relatively common, with prevalence estimates in earlier studies ranging from roughly 3 to 11 percent, and while most are benign and self-limited, some signal an underlying dermatologic, systemic, or genetic condition. The differential diagnosis in children includes atopic dermatitis, psoriasis, lichen planus, alopecia areata, vitiligo, and fungal onychomycosis, each with its own treatment implications.

The boy’s history made the diagnosis genuinely difficult. His guardians first noticed nail abnormalities at three weeks of age, and the changes gradually spread until, at presentation in October 2025, 19 nails showed marked thickening, irregular roughening, and yellow-brown opaque discoloration. Only the right fifth toenail was spared, and there was no periungual erythema or soft-tissue swelling. Dermoscopy revealed irregular whitish patches, nail fissuring, and fine longitudinal grooves. He had previously been treated with desonide cream and 0.03 percent tacrolimus ointment, each applied once daily, without satisfactory response, and his guardians declined oral corticosteroids over concerns about systemic side effects. He carried a diagnosis of allergic rhinitis, but there was no relevant family history of hereditary disease, hepatitis, or tuberculosis.

Laboratory workup pointed toward a type 2 inflammatory process. The boy’s eosinophil percentage was 9.7 percent against a reference range of 0 to 0.9 percent, his absolute eosinophil count was elevated at 0.8 times ten to the ninth per liter, and his serum immunoglobulin E was mildly raised at 172.1 IU/mL with a reference maximum of 60. Allergen testing showed sensitization to beef, mites, and mold. To rule out fungal infection, clinicians performed direct microscopy and fungal culture of nail clippings three times at one-month intervals, all consistently negative, although PAS staining and fungal PCR were unavailable. His parents refused a nail biopsy out of concern about causing permanent dystrophy. With infection excluded, biopsy unavailable, and an atopic history in hand, the team settled on atopic dermatitis-associated nail involvement as a possible diagnosis, a conclusion the authors emphasize was probabilistic rather than definitive.

Dupilumab works by binding the interleukin-4 receptor alpha subunit, blocking signaling from both interleukin-4 and interleukin-13, the two cytokines that drive type 2 inflammation, the immune pathway central to atopic dermatitis. By suppressing that pathway, the drug improves epidermal barrier dysfunction and reduces itch. After parental consent, the boy received a 400 mg loading dose followed by 200 mg every two weeks, combined with topical crisaborole ointment twice daily for two weeks. At 16 weeks, early signs of healthy nail regrowth appeared. By 32 weeks, the affected nails had nearly regained normal morphology, thickness, and coloration, and his quality-of-life and itch scores, measured on the Children’s Dermatology Life Quality Index and the Peak Pruritus Numerical Rating Scale, fell from 12 and 5 to 2 and 1. No adverse events were observed through eight months of follow-up.

The therapeutic response is scientifically meaningful because it supports, indirectly, the idea that subclinical type 2 inflammation within the nail unit drove the dystrophy. In atopic disease, Th2-derived cytokines such as IL-4, IL-13, and IL-31 sustain a chronic inflammatory microenvironment. Previous reports suggest that periungual eczema and pruritus can precede nail changes: inflamed skin around the nail folds impairs the local barrier, scratching mechanically injures the nail unit, and soaps and detergents compound the damage, together disturbing normal plate formation. What makes this case exceptional is that none of that periungual inflammation was clinically visible. The authors acknowledge that without histopathological or molecular evidence from the nail unit itself, the proposed mechanism remains speculative, but the failure of topical tacrolimus and corticosteroids followed by marked improvement on dupilumab strengthens the case for IL-4 and IL-13 as key mediators.

The report also reviews the growing, though still thin, literature on dupilumab-treated nail dystrophy. A narrative search identified six published reports covering ten patients, five single adult cases and one pediatric series of five children aged four to eight. Adult outcomes illustrate how slowly nails recover: a 55-year-old woman with median canaliform dystrophy of the thumbnail achieved complete remission by four months, a 57-year-old woman with five dystrophic fingernails and marked periungual inflammation required roughly a year to reach largely normal morphology, and a 40-year-old woman with twenty-nail dystrophy showed near-complete recovery at five months except for the thumbnails. In the pediatric series, all five children improved substantially, with several showing almost complete normalization by week 12 and durable control at week 24 to 30.

One instructive anomaly emerged from the literature review. In one adult patient, nail abnormalities actually worsened after dupilumab initiation before gradually improving with continued treatment, a course the original authors did not consider a true adverse drug reaction. Similar nail-related adverse events have not appeared in dupilumab clinical trials, so the case-report authors caution clinicians against interpreting early worsening alone as treatment failure or discontinuing the drug on that basis. Another practical point concerns timing: nail improvement typically lags behind skin and itch responses because recovery depends on the physical rate of nail growth, meaning follow-up should span at least one complete nail growth cycle before judging efficacy.

The case’s broader lesson is diagnostic humility. Extensive nail dystrophy in a child without eczema could equally suggest nail psoriasis, which affects an estimated 10 to 80 percent of psoriasis patients and presents with thimble-like pitting, splinter hemorrhages, and oil-drop discoloration, or nail lichen planus, which causes thinning, longitudinal ridging, dorsal pterygium, and distal splitting in about 10 percent of cutaneous lichen planus cases. Alopecia areata produces smaller, shallower, grid-like pitting often alongside hair loss, while onychomycosis demands mycological confirmation. The authors stress that diagnosis must integrate the nail phenotype with cutaneous findings, clinical history, and systematic exclusion of alternatives, since the severity of nail change does not necessarily track the severity of any associated skin disease.

The authors are careful about the limits of their evidence. A favorable response to dupilumab strengthens the possibility of an atopic contribution but does not establish the diagnosis, and conclusions from the wider literature remain constrained by small samples, heterogeneous follow-up, non-standardized outcome assessment, and scarce histopathological confirmation. Still, for a condition in which topical therapies failed and families often refuse invasive biopsy, the report suggests a practical pathway: when an atopic background is clinically suspected, targeted blockade of type 2 inflammation may restore nails that conventional treatment could not save. Larger prospective studies with defined outcome measures will be needed to determine which nail-dystrophy phenotypes truly benefit, but this single child’s recovery from near-total nail destruction adds a compelling data point to a rapidly evolving area of dermatology.

Subject of Research: Dupilumab treatment of extensive pediatric nail dystrophy in an atopic patient

Article Title: Nineteen nail dystrophy in an atopic background responsive to dupilumab: a case report

Article References: Zang, Y., Li, X., Li, H., Qi, J., Zhu, Q., & Zhang, G. (2026). Nineteen nail dystrophy in an atopic background responsive to dupilumab: a case report. Frontiers in Medicine, 13, Article 1938551. https://doi.org/10.3389/fmed.2026.1938551

Image Credits: AI Generated

DOI: 10.3389/fmed.2026.1938551

Keywords: dupilumab, nail dystrophy, onychodystrophy, atopic dermatitis, pediatrics, dermatology, type 2 inflammation, interleukin-4, trachyonychia, case report, biologics, immune dysregulation

Tens of millions of people worldwide remain at risk of chronic arsenic exposure, including populations in Bangladesh, India, Pakistan, Taiwan, Vietnam, Mexico, China, Argentina, Chile, and the United States. Drinking contaminated well water remains the most important route of exposure in many settings, although diet can become a dominant source once water is controlled. Rice and rice-based products contribute measurable inorganic arsenic intake, and the European Union, Taiwan, and the United States have established regulatory limits for inorganic arsenic in rice, with stricter thresholds for infant foods. Brown rice generally contains higher arsenic concentrations than polished white rice, because arsenic accumulates in the outer husk layers.

Interpreting arsenic biomarkers is complicated by seafood, which contains mostly organic arsenic species such as arsenobetaine that are considered of low toxicity and rapidly excreted. Nevertheless, seafood consumption can elevate urinary arsenobetaine and dimethylarsinate, muddying the use of total urinary arsenic as a proxy for inorganic exposure in seafood-consuming populations. Urinary arsenic speciation, which separates inorganic arsenic and its methylated metabolites monomethylarsonic acid and dimethylarsinic acid, offers a more informative metric. In a long follow-up cohort from an arsenicosis-endemic area, low-to-moderate exposure was associated with urothelial tract cancers, with susceptibility signals concentrated among individuals with lower primary methylation index or higher secondary methylation index, indicating that the body’s capacity to methylate arsenic shapes disease risk.

A striking translational advance is an artificial intelligence-based, noninvasive tool that estimates arsenic exposure from standardized photographs of the hands and feet. The algorithm leverages cutaneous stigmata such as hyperkeratosis patterns to classify exposure categories, potentially enabling scalable screening where laboratory testing is limited. This matters because arsenic leaves visible fingerprints on the skin: palmoplantar hyperkeratosis and variegated pigmentation are clinical hallmarks of chronic poisoning, and arsenic-associated skin cancers are distinguished from classical UV-related skin cancers by their multiplicity and their predilection for sun-spared skin.

The skin serves as a sentinel organ for both exposure and immune disruption. Arsenic is classified by the International Agency for Research on Cancer as a Group 1 carcinogen, yet it is often considered a weak mutagen, acting predominantly at the promotion rather than initiation stage of chemical carcinogenesis. After decades of exposure, skin cancers and keratosis may precede internal cancers of the bladder, lung, and liver, making cutaneous lesions an early surrogate indicator of systemic risk. The observation that only a subset of exposed individuals develop cancers or vascular disease suggests that host factors, including immune responses, modulate susceptibility. In patients with arsenic-associated cancers, the in vivo delayed-type hypersensitivity response, which depends on antigen-presenting cells and T cells, is impaired, and in blackfoot disease, anti-endothelial cell IgG antibodies drive endothelial proliferation and VEGF-dependent angiogenesis.

Experimental evidence reveals how arsenic differentially affects immune cell types. Arsenic selectively induces Fas-dependent apoptosis of Th2 lymphocytes, mobilizes epidermal Langerhans cells, the professional antigen-presenting cells of the epidermis, and polarizes Th1 responses in arsenical cancers. Macrophages from exposed individuals show reduced adhesion capacity and impaired phagocytosis, while monocytes from exposed children produce less superoxide anion and nitric oxide. Cytokine signatures are context-dependent: in a mouse epicutaneous sensitization model, arsenic elevated IFN-γ and IL-12 secretion, supporting Th1 polarization, but in humans with arsenic-induced skin lesions, stimulated T-cell proliferation is dose-dependently impaired with reduced IFN-γ, TNF-α, and IL-2 output. Population studies in Bangladesh reported elevated circulating type 2 cytokines, eotaxin, and IgE in exposed individuals with skin lesions, while ex vivo stimulation assays showed broader cytokine suppression, indicating that steady-state serum signatures and stimulated T-cell capacity can diverge by disease stage.

Innate inflammatory pathways emerge as a consistent theme. Subchronic arsenic exposure activates the AIM2 inflammasome in human keratinocytes and mouse skin, leading to caspase-1 activation and increased IL-1β and IL-18 production. Analyses of human skin samples in arsenic-related pathology have reported increased IL-6 and IL-17 levels with progressive increases across worsening skin-damage severity, while functional T-cell assays from exposed individuals have reported decreased IL-10 secretion. Dose-response relationships appear non-linear: within low-to-moderate exposure ranges, several studies support dose-related shifts toward innate immune activation and systemic inflammation, with West Bengal women exposed to 11–50 μg/L arsenic in groundwater showing increased monocyte CD14 expression, NF-κB signaling, and elevated circulating TNF-α, IL-6, IL-8, and IL-12 alongside reduced IL-10. At higher cumulative exposures or in patients with established arsenic-associated cancers, evidence points toward adaptive immune suppression, particularly impaired T-cell responsiveness.

Perinatal exposure represents a critical window for immune programming. In a Taiwanese birth cohort with 15-year follow-up, prenatal heavy metal exposure including arsenic was associated with cord blood IgE levels and distinct IgE trajectory patterns in relation to atopic diseases. Prenatal inorganic arsenic exposure was also linked to higher risk of atopic dermatitis in young children, and a U.S. cord-blood study showed that maternal arsenic levels were inversely associated with cord-blood T helper memory cells. Prenatal co-exposure to other metals may further modify risk; a study from China reported that prenatal co-exposure to higher levels of arsenic and thallium contributed substantially to the combined risk of allergic rhinitis. These findings highlight developmental immunotoxicology as a frontier for integrating arsenic exposure, cutaneous immunology, and allergic disease risk across the life course.

Genetic and epigenetic susceptibility further shape individual risk. TIMP3 promoter polymorphisms were associated with increased susceptibility to arsenic-induced skin cancer in an exposed cohort, with in silico analyses suggesting allele-specific transcription factor binding effects that influence matrix metalloproteinase activity and tissue architecture. Arsenic methylation capacity, repeatedly implicated in differential disease risk, is itself coupled to inherited variation: AS3MT haplotype status has been associated with DNA methylation and expression of multiple genes near AS3MT, illustrating how germline variation can shape the epigenetic context for exposure response. The review’s authors propose that integrating genotype, methylation indices, immune phenotyping, and clinical outcomes could operationalize risk stratification, while water mitigation, which has been associated with a reduced burden of arsenic-related cancers in Taiwan with substantial age-cohort effects, remains the cornerstone of primary prevention. Because cancer risk persists for years to decades after exposure reduction, targeted long-term surveillance of previously exposed communities, combined with scalable phenotyping tools and precision prevention strategies, offers the most promising path forward for the tens of millions still living with arsenic’s invisible immune legacy.

Subject of Research: Immune dysregulation as a mechanism linking chronic arsenic exposure to cancers and allergic disease

Article Title: Immune perturbation in arsenic-induced adverse health effects and cancers

Article References: Hong, C.-H., Yu, S., Wang, S.-L., Yu, H.-S., & Lee, C.-H. (2026). Immune perturbation in arsenic-induced adverse health effects and cancers. Journal of Cutaneous Immunology and Allergy, 9, Article 16386. https://doi.org/10.3389/jcia.2026.16386

Image Credits: AI Generated

DOI: 10.3389/jcia.2026.16386

Keywords: arsenic, immune dysregulation, skin cancer, environmental toxicology, allergic disease, biomonitoring, perinatal exposure, genetic susceptibility, Immune, perturbation, arsenic-induced, adverse

The research team, led by scientists at the University of Asia Pacific and BRAC University in Dhaka, recruited 44 patients diagnosed with generalized anxiety disorder and 44 age- and sex-matched healthy controls. A professional psychiatrist evaluated all participants against DSM-5 criteria, and symptom severity was quantified using the widely used 7-item Generalized Anxiety Disorder scale, or GAD-7, which scores anxiety from minimal to severe on a 0-to-21 range. The researchers deliberately excluded anyone with other psychiatric conditions, chronic liver or kidney disease, acute or chronic infections, cancer, autoimmune disorders, recent use of anxiolytic or antidepressant medication, or pregnancy, because each of these factors could independently distort circulating cytokine levels and muddy the comparison.

Blood samples were drawn from each participant, allowed to clot, centrifuged to separate the serum, and stored at minus 80 degrees Celsius until analysis. The team then quantified interleukin-4 and MCP-3 concentrations using enzyme-linked immunosorbent assays, a standard laboratory technique in which antibodies capture the target molecule from the sample and a colorimetric reaction, read at 450 nanometers, reveals how much of it is present. Concentrations were calculated against standard curves and expressed in picograms per milliliter. Statistical comparisons relied on t-tests, chi-square tests for categorical data, Spearman correlation analysis, and receiver operating characteristic curve analysis to test how well each molecule could distinguish patients from controls.

The results were striking. Patients with generalized anxiety disorder had serum interleukin-4 concentrations averaging 11.82 picograms per milliliter, less than half the 24.51 picograms per milliliter measured in healthy controls. MCP-3 moved in the opposite direction, averaging 57.80 picograms per milliliter in patients versus 34.01 in controls. Both differences were highly statistically significant, with p-values below 0.001. Crucially, the two molecules also tracked symptom severity: interleukin-4 levels correlated negatively with GAD-7 scores, with a correlation coefficient of minus 0.496, while MCP-3 correlated positively with a coefficient of 0.544. In other words, the more severe the anxiety, the lower the anti-inflammatory signal and the higher the pro-inflammatory one.

Interleukin-4 is a cytokine produced primarily by Th2 helper T cells, and it acts as a molecular brake on inflammation. It suppresses the production of inflammatory mediators such as interleukin-1, interleukin-6, tumor necrosis factor-alpha, interleukin-8, and MCP-3 itself, while boosting natural anti-inflammatory regulators like the interleukin-1 receptor antagonist. In the brain, interleukin-4 has a well-documented neuroprotective role: it nudges resident immune cells called microglia away from the classically activated M1 state, which pumps out pro-inflammatory cytokines, and toward the alternatively activated M2 state, which releases anti-inflammatory molecules such as TGF-beta and interleukin-10 and helps resolve tissue damage. Animal studies have shown that this M1-to-M2 switching, mediated through the JAK1/STAT6 signaling pathway, protects the brain after injury. A deficit of interleukin-4, the authors argue, could therefore remove a key counterweight to neuroinflammation in brain regions that govern fear and worry.

MCP-3, by contrast, belongs to the CC chemokine family, a group of signaling proteins that guide immune cells to sites of inflammation through a process called chemotaxis. Structurally and functionally similar to its better-known cousin MCP-1, MCP-3 is a potent attractant for monocytes, T cells, natural killer cells, basophils, eosinophils, and dendritic cells. It exerts these effects by binding to the CCR2 receptor, found abundantly on monocytes and activated lymphocytes, and also to the CCR1 receptor. Studies in genetically engineered mice lacking MCP-3 have confirmed that the chemokine is a key driver of monocyte recruitment to inflamed tissue. Elevated MCP-3 in anxiety patients thus suggests an active mobilization of inflammatory cells, consistent with the hypothesis that chronic low-grade inflammation feeds into the biology of persistent worry.

The diagnostic potential of the two molecules was assessed with receiver operating characteristic analysis, which plots sensitivity against specificity across different cutoff values. MCP-3 emerged as the stronger performer, achieving an area under the curve of 0.848, with 87.6 percent sensitivity and 84.3 percent specificity at a cutoff of 45.0 picograms per milliliter. Interleukin-4 performed respectably but less impressively, with an area under the curve of 0.782, 80.2 percent sensitivity, and 78.5 percent specificity at a cutoff of 15.0 picograms per milliliter. An area under the curve approaching 0.85 is generally considered good discrimination, meaning a single blood test for MCP-3 could potentially flag a substantial majority of true anxiety cases while correctly clearing most healthy people, though it would not replace clinical assessment on its own.

The findings fit within a broader and sometimes contradictory literature. Preclinical work has repeatedly shown that injecting pro-inflammatory cytokines such as interleukin-1beta, interleukin-6, or tumor necrosis factor-alpha into animals induces anxiety-like behavior, and that this effect can be reversed by anti-inflammatory cytokines like interleukin-4 and interleukin-10. Clinical studies have often reported elevated pro-inflammatory and reduced anti-inflammatory cytokines in anxious patients, although some studies have found no differences or even lowered pro-inflammatory signals, highlighting how inconsistent the field remains. The cytokine hypothesis of anxiety proposes that pro-inflammatory molecules reduce serotonin production or increase its reuptake, thereby disturbing the serotonergic signaling that current medications like selective serotonin reuptake inhibitors are designed to enhance. Notably, roughly half of patients with generalized anxiety disorder do not respond adequately to existing drugs, and symptoms recur in at least 30 percent, underscoring the need for new mechanistic angles.

The study’s authors also see therapeutic potential in the interleukin-4/MCP-3 axis. Anti-cytokine monoclonal antibodies are already transforming the treatment of autoimmune diseases: secukinumab, ixekizumab, and bimekizumab block interleukin-17A, while ustekinumab targets interleukin-23A, and these agents are used in inflammatory bowel disease, psoriatic arthritis, and rheumatoid arthritis. If the same logic applies to anxiety, drugs that restore interleukin-4 signaling or dampen MCP-3-driven monocyte recruitment could one day complement or improve upon existing anxiolytics. The authors caution, however, that the immune system is finely balanced and that any such approach would require a deep understanding of which immune processes actually drive the disorder rather than merely accompany it.

Important limitations temper the excitement. The sample of 88 participants is small and drawn from a single Bangladeshi clinical setting, so the results may not generalize to other populations. As a case-control design, the study can demonstrate association but not causation; it remains unclear whether immune dysregulation contributes to causing anxiety, whether anxiety itself alters immune function, or whether both are driven by a third factor. The researchers also lacked detailed records of psychopharmacological treatment, and since antidepressants can themselves modulate inflammatory pathways, this absence may have confounded the observed associations. Sociodemographic differences in economic status and family history between the groups further complicate interpretation. The authors call for longitudinal studies with comprehensive medication histories to clarify the temporal dynamics of immune dysregulation as generalized anxiety disorder develops and progresses. Until then, the study stands as a compelling piece of evidence that the blood carries echoes of the anxious mind, and that measuring those echoes may one day help clinicians detect, grade, and treat one of the world’s most burdensome psychiatric conditions.

Subject of Research: Association of serum interleukin-4 and monocyte chemoattractant protein-3 levels with generalized anxiety disorder

Article Title: Altered serum interleukin-4 and monocyte chemoattractant protein-3 levels are associated with generalized anxiety disorder: a case-control study

Article References: Binta Rashid, M. H., Islam, M., Ashraful Islam, S. M., & Islam, M. R. (2026). Altered serum interleukin-4 and monocyte chemoattractant protein-3 levels are associated with generalized anxiety disorder: a case-control study. Experimental Biology and Medicine, 251, Article 11144. https://doi.org/10.3389/ebm.2026.11144

Image Credits: AI Generated

DOI: 10.3389/ebm.2026.11144

Keywords: generalized anxiety disorder, interleukin-4, MCP-3, cytokines, neuroinflammation, biomarkers, ELISA, ROC analysis, immune dysregulation, case-control study, microglia, anxiety severity

The trial recruited patients from the Long COVID Outpatient Clinic at IRCCS Fondazione Ca’ Granda Ospedale Maggiore Policlinico between November 2022 and November 2023. Of 347 individuals screened, 53 met the strict inclusion criteria: documented SARS-CoV-2 infection, persistent symptoms lasting at least three months, and clinically relevant fatigue defined by a Chalder Fatigue Scale (CFS) score of at least 4 out of 11. After excluding five participants with low adherence, 48 patients completed the study, 25 in the placebo arm and 23 in the VSL#3 arm. The cohort was evenly split between sexes, with a median age of 54 years and a median symptom duration of 30 months, underscoring how entrenched these symptoms had become.

VSL#3 is no ordinary probiotic. Each sachet delivers 450 billion colony-forming units of eight live freeze-dried bacterial strains, including four Bifidobacterium and four Lactobacillus species along with Streptococcus thermophilus. Participants took two sachets daily for 28 days, with placebo sachets identical in appearance, smell, and taste. The choice of formulation was deliberate: several of its constituent genera, particularly Bifidobacterium and Lactobacillus, have been repeatedly reported as depleted in patients with COVID-19 and long COVID, and their loss has been linked to persistent inflammation and symptom burden.

The primary endpoint was unambiguous. Patients receiving VSL#3 experienced a 24.24 percent median reduction in CFS score, compared with just 6.06 percent in the placebo group, a difference that reached statistical significance at p = 0.037. The responder rate told an even clearer story: 68 percent of VSL#3-treated patients improved meaningfully, versus 35.7 percent of those on placebo (p = 0.019). Crucially, the clinical benefit was maintained at the four-week follow-up visit after treatment discontinuation, arguing against a purely transient effect of the supplementation period.

Beyond fatigue, the trial captured improvements across selected patient-reported outcomes. Quality-of-life measures from the SF-36 survey showed gains in physical functioning and role limitation due to emotional problems in the VSL#3 group, and gastrointestinal symptom scores improved as well, with notable reductions in epigastric pain. These parallel improvements align with the trial’s underlying hypothesis: that the gut, far from being a bystander in long COVID, may be an active participant in the disease process.

To probe the biological mechanisms, the researchers layered clinical outcomes with an ambitious multi-omic workup. Fecal samples underwent 16S rRNA gene sequencing to profile gut microbiota composition, while targeted metabolomics quantified short-chain fatty acids and neuromodulators such as dopamine and serotonin in both fecal and serum samples. Blood analyses included immune cell phenotyping by multiparametric flow cytometry and serum cytokine profiling using a 45-plex Luminex panel. The integration of these datasets allowed the team to look for coordinated patterns linking microbial changes, immune signaling, and clinical response.

The microbiota findings were selective rather than sweeping. Overall microbial diversity, measured by alpha and beta diversity indices, did not differ significantly between groups at baseline or after treatment. Yet differential abundance analysis revealed that VSL#3 supplementation enriched specific health-associated taxa, including Bifidobacterium, Lactobacillus, Streptococcus, and Barnesiella, several of which correspond to strains in the administered formulation. Notably, clinical responders showed a distinct microbial signature beyond the supplemented organisms, with enrichment of commensal genera such as Bacteroides, Ruminococcus, Coprococcus, Phascolarctobacterium, Akkermansia, and Clostridium cluster IV, taxa associated with short-chain fatty acid production and gut ecosystem balance. Functional prediction analysis also pointed to enrichment of glycine, threonine, and methionine metabolism pathways in the VSL#3 group.

On the immune front, the results were more cautious. Within the VSL#3 group, circulating levels of IL1α, IL6, IL7, IFNα, and G-CSF declined from baseline to the end of treatment, hinting at a partial attenuation of the persistent low-grade immune activation characteristic of long COVID. However, these cytokine changes did not reach statistical significance when compared directly with the placebo arm, and the authors emphasize they should be interpreted as exploratory, hypothesis-generating observations. Immune cell phenotyping did reveal remodeling of peripheral populations, with increased proportions of CD8-positive T cells and CD68-positive macrophages alongside reduced CD66b-positive granulocytes, suggesting a shift in innate and adaptive immune balance following supplementation.

Perhaps the most intriguing findings emerged from correlation analyses linking the three data layers. In responder patients, the bacterial genus Coprococcus showed positive associations with the anti-inflammatory cytokine IL10 and with IL7, while isovaleric acid correlated positively with Coprococcus and valeric acid with Ruminococcus. Conversely, in non-responders, Akkermansia showed negative correlations with IL17 and G-CSF. These coordinated microbiota-immune-metabolic patterns, the authors suggest, may reflect broader interaction networks relevant to gut-brain communication, the axis increasingly implicated in fatigue and neurocognitive symptoms across long COVID and related post-infectious conditions such as myalgic encephalomyelitis/chronic fatigue syndrome.

The study’s strengths include its randomized, double-blind, placebo-controlled design and the depth of its integrated analyses, but the authors are candid about limitations: the small cohort size, the short post-treatment follow-up, the exploratory nature of the multi-omic work, and the inability to resolve whether enriched taxa represent durable microbiota remodeling or transient detection of supplemented strains. Longer-term, strain-resolved shotgun metagenomic studies will be needed to settle that question. Still, the persistence of clinical benefit four weeks after treatment stopped, combined with the enrichment of commensal taxa not present in the formulation, offers a compelling signal. As the first randomized placebo-controlled evidence supporting microbiota-targeted intervention for long COVID fatigue, the DELong#3 trial opens a concrete path for larger trials that could finally translate gut-directed therapy from hypothesis to standard of care.

Subject of Research: A randomized placebo-controlled trial of VSL#3 probiotic supplementation for fatigue in long COVID patients, with integrated microbiota, immune, and metabolomic analyses

Article Title: VSL#3® supplementation improves fatigue in long COVID: results from the DELong#3 randomized placebo-controlled trial

Article References: Amoroso, C., Marinoni, B., Maragno, P., Rimondi, A., Bottaro, F., Ciafardini, C., Muià, M., Honcharyuk, I., Noviello, D., Caridi, B., Sommella, E. M., Bandera, A., Gori, A., Mantero, M., Blasi, F., Ferrucci, R., Priori, A., Strati, F., Vecchi, M., … Caprioli, F. (2026). VSL#3® supplementation improves fatigue in long COVID: results from the DELong#3 randomized placebo-controlled trial. British Journal of Biomedical Science, 83, Article 16993. https://doi.org/10.3389/bjbs.2026.16993

Image Credits: AI Generated

DOI: 10.3389/bjbs.2026.16993

Keywords: long COVID, VSL#3, probiotics, gut microbiota, fatigue, randomized controlled trial, immune dysregulation, microbiota-gut-brain axis, Chalder Fatigue Scale, short-chain fatty acids, Bifidobacterium, metabolomics

Atopic dermatitis affects a substantial share of children, often appearing in the first years of life with intensely itchy, inflamed patches on the face, flexures of the arms and legs, and trunk. Its roots lie in a combination of barrier defects in the skin, genetic susceptibility, and dysregulated immune responses dominated by type 2 inflammatory pathways. Obesity, meanwhile, is no longer viewed as a passive state of energy surplus. Adipose tissue actively secretes hormones, cytokines, and signaling lipids that reshape systemic inflammation. The review’s central premise is that these two biological narratives—barrier failure and immune misfiring on one side, metabolically driven low-grade inflammation on the other—may converge in the same child, with measurable consequences for disease risk and severity.

The research team undertook a systematic synthesis of studies that had previously investigated the relationship between body mass index, overweight, obesity, and atopic dermatitis in pediatric populations. Among the key works the reviewers examined were a 2024 national cross-sectional analysis from Korea published in PLoS ONE, which assessed the association between body mass index and atopic dermatitis among adolescents; case-control studies from 2011 and 2023 that compared obesity rates in children with and without the skin condition; a 2015 JAMA Dermatology investigation linking central obesity with high blood pressure in pediatric atopic dermatitis patients; and a 2022 JAMA Dermatology cohort analysis of atopic dermatitis and growth parameters including height, weight, and body mass index in children. By drawing these threads together, the review offers a consolidated view of a literature that has often produced seemingly inconsistent results.

That inconsistency is itself scientifically revealing. Some studies report that children with obesity carry higher odds of developing atopic dermatitis or experience more severe disease, while others find no meaningful relationship—or even signals pointing the opposite way. One frequently cited example in the literature is a Finnish follow-up study of children after infantile bronchiolitis, which found that overweight did not increase asthma risk and might even be associated with lower allergy risk at school age. Such discordance underscores a central challenge: the direction and strength of any obesity–eczema link may depend on how obesity is measured, whether total body mass or central adiposity is the exposure of interest, how atopic dermatitis is defined, and whether the outcome is diagnosis, severity, or persistence of disease.

Measurement issues loom large in this field. Body mass index, the most widely used metric, is a crude proxy that cannot distinguish lean mass from fat mass or capture the distribution of adipose tissue. Yet fat distribution may matter biologically, because visceral or central obesity generates a more pro-inflammatory milieu than subcutaneous fat. The 2015 JAMA Dermatology study highlighted in the review focused specifically on central obesity and found it associated with elevated blood pressure among children with atopic dermatitis, hinting that the metabolic complications of adiposity and the inflammatory burden of eczema may compound one another. Meanwhile, a longitudinal birth cohort analysis of fetal growth, obesity, and atopic disorders in adolescence suggests that early-life growth trajectories could program later allergic risk, adding a developmental dimension that cross-sectional snapshots cannot capture.

Beneath the epidemiology lies a set of plausible mechanistic pathways. Adipocytes release pro-inflammatory adipokines such as leptin, which can amplify T-cell activity, and reduced levels of anti-inflammatory adiponectin, potentially tipping immune balance toward the type 2 skew characteristic of atopic disease. Obesity is also associated with chronic oxidative stress and altered gut microbiome composition, both of which have been implicated in eczema pathogenesis. Mechanical factors may contribute as well: skin folds in children with obesity create warm, moist microenvironments prone to friction and microbial overgrowth, including colonization by Staphylococcus aureus, a well-known trigger of atopic dermatitis flares. Conversely, the relationship could run in reverse, with itchy, sleep-disrupting eczema limiting physical activity and promoting weight gain—a bidirectional dynamic that most observational studies are poorly equipped to disentangle.

The timing question—does obesity precede eczema, follow it, or simply co-develop—remains the critical unresolved issue, and it is precisely where systematic reviews earn their keep. The McMaster team’s synthesis of case-control designs, which enroll children with and without disease and look backward at exposures, alongside cross-sectional surveys that capture a single moment in time, and longitudinal cohorts that track growth and disease over years, provides a map of where the evidence is strongest and where it frays. Their review, published as a research letter, reflects a deliberate effort to distill a sprawling and sometimes contradictory body of work into a form that clinicians and researchers can act upon, rather than adding another single-population data point to an already crowded field.

For pediatricians and dermatologists, the stakes are practical. If excess adiposity genuinely worsens atopic dermatitis risk or severity, then weight management could become an explicit adjunct to eczema care, complementing emollients, topical anti-inflammatory agents, and the newer systemic therapies that have transformed treatment for moderate-to-severe disease. Conversely, if eczema drives inactivity and weight gain, early aggressive control of itch and inflammation might protect against obesity downstream. Either scenario would justify closer monitoring of growth parameters and metabolic health in children with atopic dermatitis, a population in whom the JAMA Dermatology hypertension findings suggest cardiovascular risk factors may already be converging.

The review also exposes the limitations of the current evidence base. Heterogeneous definitions of pediatric obesity, reliance on parent-reported eczema diagnoses in some surveys, confounding by diet, socioeconomic status, and shared environmental triggers, and the scarcity of interventional data all temper the certainty of any conclusion. The authors note that no datasets were generated or analyzed anew in their study, positioning the work squarely as an interpretive synthesis rather than a primary analysis. Future progress, they and others in the field suggest, will depend on large prospective cohorts with objective adiposity measures, standardized eczema phenotyping, and mediation analyses that can test whether weight change causally shifts disease trajectories.

What emerges from this systematic review is neither a simple alarm nor a dismissal, but a call for precision. Childhood obesity and atopic dermatitis are each formidable public health burdens on their own; the possibility that they amplify one another through shared inflammatory, metabolic, and behavioral pathways makes understanding their intersection a priority. As prevalence curves for both conditions continue to rise, studies like this one from the McMaster group provide the evidentiary scaffolding on which the next generation of longitudinal and mechanistic research—and eventually, targeted prevention strategies—can be built.

Subject of Research: The association between childhood obesity and atopic dermatitis in children

Article Title: The association between childhood obesity and atopic dermatitis: a systematic review

Article References: Sehjal, M., Branyiczky, M. K., Akomolafe, E., & Abu-Hilal, M. (2026). The association between childhood obesity and atopic dermatitis: a systematic review. Archives of Dermatological Research, 318(1), Article 427. https://doi.org/10.1007/s00403-026-04874-3

Image Credits: AI Generated

DOI: 10.1007/s00403-026-04874-3

Keywords: childhood obesity, atopic dermatitis, eczema, systematic review, pediatrics, inflammation, body mass index, adipokines, skin barrier, immune dysregulation, metabolic health, dermatology

The clinical picture the review describes is dominated by a symptom that has no equivalent in most other diseases: post-exertional malaise, or PEM. Patients with ME/CFS experience a worsening of fatigue, pain, cognitive dysfunction, and other symptoms after physical or mental exertion, and the deterioration is disproportionate and delayed, often appearing a day or more after the triggering activity. The authors identify PEM as the cardinal feature of the disease, the hallmark that most reliably distinguishes it from ordinary fatigue or depression. Alongside PEM, the core clinical characteristics include persistent, unexplained fatigue that does not resolve with rest, unrefreshing sleep, and cognitive impairment that patients frequently describe as brain fog. Multisystem involvement means that cardiovascular, gastrointestinal, neurological, and immunological symptoms can all coexist in the same patient, making the presentation bewilderingly heterogeneous.

That heterogeneity has been one of the greatest obstacles to scientific progress. The review traces the history of diagnostic criteria for ME/CFS and finds a succession of definitions that varied widely in their requirements, producing patient populations that were not comparable across studies. Some earlier criteria emphasized fatigue alone, a choice that allowed conditions such as major depressive disorder to be folded into the diagnosis and reinforced the historical linkage of ME/CFS to psychiatry. The authors are blunt about the consequences: inconsistent diagnostics, the absence of any validated biomarker, and decades of psychological framing delayed recognition of the disease and marginalized the patients living with it. Diagnosis today remains clinical, resting on symptom patterns and the exclusion of other conditions, which means that underdiagnosis is widespread and prevalence estimates vary considerably across countries and study designs.

One of the most consequential shifts documented in the review concerns treatment. For years, graded exercise therapy was offered to ME/CFS patients on the theory that deconditioning perpetuated their symptoms and that carefully escalated activity would restore function. The review notes that this approach has now been formally withdrawn from treatment guidelines, with evidence of harm: for a disease in which exertion itself triggers pathological worsening, pushing patients to exercise can precipitate severe and prolonged relapses. The withdrawal represents an acknowledgment that a treatment paradigm built on the wrong model of the disease caused real damage. Pacing, the strategy of carefully balancing activity and rest to stay within an individual’s energy envelope, remains a pragmatic management approach, but the review is clear that no disease-modifying treatment currently exists.

The pathophysiological section of the review is where the technical story becomes most compelling. Multiple independent lines of evidence now point to mitochondrial dysfunction as a central abnormality. Mitochondria are the cellular power plants that convert nutrients into adenosine triphosphate, the molecular currency of energy, and studies in ME/CFS patients have found impaired energy production and abnormal metabolic profiles consistent with cells that cannot generate ATP efficiently. Metabolomic assays, which survey hundreds of small molecules in blood or urine, have detected reproducible disturbances in energy metabolism pathways, and some researchers have proposed these metabolic signatures as candidate diagnostic biomarkers. Electrophysiological assays, which measure the electrical activity of cells, offer another emerging tool for objectifying a disease that has long lacked laboratory confirmation.

Immune dysregulation forms a second pillar of the pathophysiological evidence. The review describes abnormalities in immune cell function and inflammatory signaling that suggest the immune system in ME/CFS is chronically activated yet ineffective, a state that could explain both the flu-like symptoms many patients report and their vulnerability to symptom flares. Autonomic imbalance is a third strand: dysregulation of the autonomic nervous system, which controls heart rate, blood pressure, and other involuntary functions, manifests as orthostatic intolerance and other cardiovascular symptoms that worsen when patients stand upright. Neuroinflammation, inflammation within the central nervous system, provides a plausible mechanism for the cognitive impairment that so many patients experience. Finally, alterations in the gut microbiome, the community of microorganisms inhabiting the intestine, have been documented in ME/CFS and may contribute to systemic inflammation through the gut-immune axis.

On the therapeutic frontier, the review highlights several strategies under investigation. Among the most intriguing are mTOR inhibitors, drugs that modulate the mechanistic target of rapamycin pathway, a central cellular signaling hub that regulates metabolism, growth, and autophagy. Given the metabolic disturbances observed in patients, pathway modulation represents a rational therapeutic hypothesis, though the authors present it as exploratory rather than established. The review also emphasizes methodological innovation: decentralised clinical trial designs, which recruit and follow participants remotely rather than requiring frequent visits to academic centers, could overcome one of the practical barriers that has hampered ME/CFS research, namely that the disease itself often prevents patients from traveling to study sites.

The intersection with Long COVID receives particular emphasis as a scientific accelerant. A substantial fraction of people infected with SARS-CoV-2 develop a chronic post-infectious syndrome whose symptoms overlap strikingly with ME/CFS, including PEM, cognitive dysfunction, and unrefreshing sleep. The review frames this convergence as a chance to rapidly advance the study of post-infectious chronic diseases more broadly, because Long COVID has attracted funding, patient cohorts, and scientific talent on a scale ME/CFS never achieved. Insights from one condition are likely to inform the other, and the enlarged research community now working on post-acute infection syndromes may finally supply the mechanistic answers that decades of ME/CFS research struggled to reach in isolation.

To convert this momentum into durable progress, the authors argue for stringent subtyping of patients, uniform data collection across studies, and ongoing patient participation in research design. Subtyping acknowledges that ME/CFS may encompass several distinct biological subgroups with different triggers and mechanisms, and that pooling them has obscured signals in past studies. Standardized data collection would make findings comparable across laboratories and countries, while involving patients, who possess detailed experiential knowledge of symptom patterns and treatment harms, would help ensure that research questions and outcome measures are clinically meaningful. The review closes with a call for equitable research funding, contending that biomarker discovery and the development of disease-modifying treatments will remain out of reach until investment matches the disease burden. Caring for people with ME/CFS, the authors conclude, is not only a clinical obligation but a public health one, a statement that would have been difficult to publish in a major translational medicine journal a generation ago.

Subject of Research: Pathophysiology, diagnosis, and treatment of myalgic encephalomyelitis/chronic fatigue syndrome

Article Title: Comprehensive review of myalgic encephalomyelitis/chronic fatigue syndrome

Article References: Jeyaraman, M., Jeyaraman, N., Ramasubramanian, S., Schäfer, L., Migliorini, F., & Balaji, S. (2026). Comprehensive review of myalgic encephalomyelitis/chronic fatigue syndrome. Journal of Translational Medicine. https://doi.org/10.1186/s12967-026-08833-4

Image Credits: AI Generated

DOI: 10.1186/s12967-026-08833-4

Keywords: ME/CFS, chronic fatigue syndrome, post-exertional malaise, mitochondrial dysfunction, neuroinflammation, immune dysregulation, autonomic dysfunction, gut microbiome, Long COVID, graded exercise therapy, diagnostic criteria, biomarkers

The research team, led by Qianqian Yin and Yaru Yang of Xuzhou Central Hospital affiliated with Southeast University, together with colleagues including corresponding authors Xiaoyan Liu and Jianhua Zheng, recruited twenty patients diagnosed with PMOS and ten control women. Follicular fluid, the nutrient-rich liquid surrounding the oocyte inside each ovarian follicle, was collected during procedures related to in vitro fertilization and embryo transfer. Because this fluid is in direct contact with the developing egg and the surrounding cumulus cells, it offers a uniquely intimate window into the microenvironment in which fertilization competence is established. Rather than studying blood, where systemic changes can be diluted and confounded, the researchers chose to interrogate the immediate biochemical neighborhood of the egg itself.

The technological centerpiece of the study was four-dimensional label-free quantitative proteomics, an approach that has rapidly become one of the most powerful tools in modern biology. Traditional proteomic methods separate peptides along a single dimension of mass spectrometric analysis, but four-dimensional platforms add ion mobility separation and retention time alignment, dramatically increasing the depth, resolution, and accuracy of protein identification. Label-free quantification, meanwhile, avoids the chemical labeling steps that can introduce bias and expense, instead relying on the raw intensity of detected peptide signals to estimate relative protein abundance across samples. This combination allowed the team to comprehensively profile the whole proteome of follicular fluid and to detect subtle but meaningful differences between patient groups that earlier methods might have missed.

When the data were analyzed with strict statistical thresholds requiring a fold change greater than 1.5 and a p-value below 0.05, thirty-three proteins emerged as differentially expressed between the PMOS and control groups. Twenty-four of these proteins were elevated in the patients, while nine were reduced. That modest number may sound unremarkable, but each of these molecules represents a potential thread in the tangled web of PMOS pathogenesis, and the patterns revealed by subsequent bioinformatic analysis were strikingly coherent rather than random.

Functional enrichment analysis using the Gene Ontology framework showed that the altered proteins clustered around several biological themes. The first was immunoglobulin production and the humoral immune response, indicating that antibody-mediated immune activity is heightened within the follicular environment of PMOS patients. The second was leukocyte migration, suggesting that immune cells are being actively recruited into the ovarian follicle. The third and perhaps most surprising theme was cellular energy metabolism, with proteins involved in glycolysis and pyruvate metabolism prominently represented. These findings imply that the follicle in PMOS is not merely a passive site of hormonal dysfunction but an active immunometabolic battlefield where energy production and immune defense are simultaneously rewired.

Pathway-level analysis using the Kyoto Encyclopedia of Genes and Genomes reinforced this picture. The differentially expressed proteins were predominantly enriched in glycolysis and gluconeogenesis, pyruvate metabolism, the hypoxia-inducible factor-1 signaling pathway, and extracellular matrix-receptor interactions. The involvement of HIF-1 signaling is particularly intriguing. This pathway is the cell’s master response to low oxygen, and its activation can drive cells to shift their energy production from efficient mitochondrial respiration toward rapid but wasteful glycolysis, a phenomenon famously exploited by cancer cells. Its enrichment in PMOS follicular fluid raises the possibility that the ovarian follicle in these patients exists in a state of relative hypoxia or metabolic stress, forcing the egg and its supporting cells to operate under conditions that may compromise developmental potential.

Protein-protein interaction network analysis added another layer of insight, suggesting a synergistic relationship between metabolic reprogramming and immune dysregulation in PMOS. In other words, the altered energy metabolism and the disturbed immune signaling do not appear to be independent phenomena but are likely intertwined, each feeding into and amplifying the other. This kind of systems-level view is exactly what proteomics is designed to deliver, and it points toward a conceptual model in which PMOS arises from a self-reinforcing loop of inflammatory and metabolic disturbance within the ovary, rather than from a single defective gene or hormone.

To ensure that the mass spectrometry findings were not artifacts, the team turned to enzyme-linked immunosorbent assay, a targeted and highly specific method for measuring individual proteins. Three candidates were selected for validation: L-lactate dehydrogenase A chain, known as LDHA, a key enzyme that drives the final step of glycolysis and converts pyruvate into lactate; protein S100-A9, or S100A9, an inflammatory mediator released by neutrophils and monocytes that acts as a danger signal to the immune system; and serum amyloid A1, or SAA1, an acute-phase protein classically associated with inflammation and tissue remodeling. All three were confirmed to be significantly higher in the follicular fluid of PMOS patients than in controls, lending robust analytical credibility to the discovery set and highlighting a concrete biochemical axis linking glycolytic flux, inflammation, and acute-phase response within the follicle.

The implications of this work are twofold. Clinically, the identified proteins could serve as diagnostic biomarkers, offering a way to identify or monitor PMOS through a simple assessment of follicular fluid, and potentially as therapeutic targets whose modulation might restore a healthier follicular environment. Scientifically, the study reframes PMOS as a disorder of immunometabolic reprogramming and extracellular matrix remodeling, providing a new perspective on pathogenesis that goes beyond the traditional focus on androgen excess and insulin resistance. The authors are careful to note the limitations of their work: the sample size was modest, with twenty patients and ten controls, and the findings now require validation in larger cohorts, ideally integrated with detailed clinical phenotypes and functional experiments that can test whether the candidate proteins play causal roles or are merely markers of the disease process.

Nevertheless, the study stands as a compelling example of how cutting-edge proteomic technology can illuminate diseases that have long resisted conventional investigation. By capturing a snapshot of the protein milieu surrounding the human egg, Yin, Yang, and their colleagues have transformed PMOS from a vaguely defined clinical syndrome into a condition with a measurable molecular fingerprint. If subsequent research confirms and extends these findings, the glycolytic enzymes, inflammatory proteins, and matrix components identified in follicular fluid could become the foundation for new diagnostic tests and, ultimately, new treatments aimed at protecting the delicate metabolic environment in which every human life begins.

Subject of Research: Proteomic profiling of follicular fluid in polyendocrine metabolic ovarian syndrome

Article Title: Identification of differentially expressed proteins in follicular fluid from patients with polyendocrine metabolic ovarian syndrome using 4D label-free proteomics

Article References: Yin, Q., Yang, Y., Yan, X., Cao, Y., Liu, X., & Zheng, J. (2026). Identification of differentially expressed proteins in follicular fluid from patients with polyendocrine metabolic ovarian syndrome using 4D label-free proteomics. Journal of Ovarian Research. https://doi.org/10.1186/s13048-026-02271-y

Image Credits: AI Generated

DOI: 10.1186/s13048-026-02271-y

Keywords: polyendocrine metabolic ovarian syndrome, follicular fluid, proteomics, 4D label-free quantification, glycolysis, HIF-1 signaling, immune dysregulation, LDHA, S100A9, SAA1, biomarkers, fertility