In classical medicine, ileus referred to a violent, often fatal condition of the abdomen in which the intestines were believed to be gripped by pain and dysfunction. Ancient and early modern physicians used the term for what they described as intestinal colic or a twisting suffering of the gut, a syndrome recognized by severe abdominal distension, vomiting, and collapse. The word carried an aura of dread. For centuries, ileus was less an anatomical diagnosis than a description of a catastrophic clinical picture, one that physicians could observe but rarely explain and almost never treat.

As Ballantyne documented in a 1984 review of the term’s changing definition over three millennia, the modern era brought a decisive shift. By the nineteenth and early twentieth centuries, surgeons increasingly distinguished between mechanical obstruction of the bowel, in which a physical blockage halts the passage of intestinal contents, and paralytic or adynamic ileus, in which the bowel wall simply stops moving. This distinction mattered enormously for practice. A mechanical obstruction demanded surgical relief, while a paralyzed bowel called for decompression, supportive care, and patience. The word ileus, once a single ominous label, had split into two conceptually different diseases, and the tension between those meanings would soon shape how one of pediatrics’ signature conditions was first recognized.

It was against this backdrop that the earliest reports of meconium ileus appeared. In 1905, Karl Landsteiner, the Viennese pathologist better known for his discovery of the ABO blood groups, published a description of intestinal obstruction caused by inspissated, or thickened and dried, meconium, which he linked to pancreatic disease. Writing in German, Landsteiner described a bowel blocked not by a band, a volvulus, or an atresia, but by abnormally dense fetal intestinal contents. His observation connected two organ systems, gut and pancreas, in a way that would prove prophetic, though the full significance of that connection took decades to appreciate.

The term meconium ileus itself emerged in the clinical literature shortly afterward. In 1919, Bullowa and Brennan reported a case of intrauterine intestinal obstruction from inspissated and impacted meconium in the Journal of the American Medical Association, framing the problem as a mechanical obstruction present before birth. Here the older, mechanical sense of ileus was doing quiet work: the authors were not describing a paralyzed bowel but a bowel physically plugged by tenacious meconium. The phrase captured a paradox that would puzzle clinicians for years, namely that a newborn could be born already obstructed by a substance that should have passed harmlessly in the first days of life.

Through the 1920s and 1930s, case reports accumulated. In 1936, Dodd published a case report in the Journal of Pediatrics of intestinal obstruction due to meconium ileus in a newborn infant, and the same year Eliason and Johnson addressed the diagnostic features of ileus in the journal Radiology, reflecting the growing role of abdominal radiography in distinguishing patterns of bowel obstruction. Radiographs allowed clinicians to see dilated loops of bowel and, in some cases, a characteristic granular or ground-glass appearance where thick meconium mixed with air. Imaging gave the condition a visible signature and helped separate it from other causes of neonatal obstruction such as atresia, stenosis, and volvulus.

The decisive conceptual breakthrough came in 1936 and 1938. In 1936, Fanconi, Uehlinger, and Knauer published their description of the celiac syndrome associated with congenital cystic fibromatosis of the pancreas and bronchiectasis, drawing together the intestinal, pancreatic, and pulmonary features that had previously been reported in isolation. Two years later, Dorothy Andersen, in a landmark clinical and pathological study in the American Journal of Diseases of Children, defined cystic fibrosis of the pancreas as a distinct disease and established its relationship to the celiac-like syndrome of infants. Within this new framework, meconium ileus found its place: it was not a random mechanical accident of fetal life but the earliest clinical manifestation of a hereditary disorder that thickened secretions throughout the body.

Once cystic fibrosis was defined, the meaning of meconium ileus settled into its modern form. The condition is now understood as neonatal intestinal obstruction caused by abnormally viscous meconium, the product of deficient pancreatic enzyme secretion and altered mucus, which accumulates in the terminal ileum and cecum and produces a mechanical blockage. In the vocabulary of the early twentieth century, that made meconium ileus a true mechanical ileus, in the tradition of Steele’s 1901 discussion of ileus due to mechanical obstruction to the fecal current, rather than a paralytic ileus of the kind Wathen described in his 1909 JAMA paper on postoperative ileus. The newborn bowel in meconium ileus is not lazy; it is blocked, and it strains against a plug of material too thick to pass.

Zarka’s commentary highlights how this history illustrates a broader point about medical language. The word ileus arrived in the meconium literature carrying its ancient sense of severe intestinal suffering, was refined by surgeons into a distinction between mechanical and adynamic obstruction, and then, in the phrase meconium ileus, preserved a specific mechanical meaning that clinical experience gradually clarified. What began as a descriptive label for a mysterious neonatal catastrophe became, through the accumulation of cases, the application of new imaging techniques, and the recognition of cystic fibrosis, a precise diagnostic entity with a defined pathophysiology. The forgotten layers of the term’s meaning were not lost so much as overwritten, and revisiting them reveals how much of modern terminology encodes older debates.

The story also underscores the value of clinical observation in advance of molecular understanding. Landsteiner linked inspissated meconium to pancreatic disease decades before the genetic basis of cystic fibrosis was known. Bullowa and Brennan recognized intrauterine obstruction before any treatment was possible. Andersen’s synthesis transformed scattered reports into a coherent disease concept. Each step depended on clinicians taking seriously what they saw at the bedside and in the pathology laboratory, and on a vocabulary flexible enough, despite its tangled history, to carry those observations forward. In the case of meconium ileus, the curious history of a single word helped keep a forgotten meaning alive long enough for medicine to give it a name, a mechanism, and eventually a place within one of the most common hereditary diseases of childhood.

Subject of Research: The historical evolution of the term ileus and its role in the recognition of meconium ileus as an early manifestation of cystic fibrosis

Article Title: The curious history of meconium ileus: how clinical experience revived a forgotten meaning

Article References: Zarka, A. (2026). The curious history of meconium ileus: how clinical experience revived a forgotten meaning. Pediatric Radiology. https://doi.org/10.1007/s00247-026-06777-x

Image Credits: AI Generated

DOI: 10.1007/s00247-026-06777-x

Keywords: meconium ileus, ileus, cystic fibrosis, history of medicine, Karl Landsteiner, Dorothy Andersen, pediatric radiology, intestinal obstruction, neonatology, medical terminology, pancreatic disease, clinical history

Researchers at the Children’s Hospital of Chongqing Medical University reviewed the records of pediatric patients with intussusception who underwent colonoscopy between 2015 and 2023. Over that nine-year window, 63 children, 34 boys and 29 girls with an average age of 5.46 years, were examined with the flexible endoscope after their intussusception episode. The children had been symptomatic for a median of two days, and most had already undergone a median of two air enemas before the decision was made to look inside the bowel directly. That detail matters, because it frames colonoscopy not as a first-line diagnostic tool but as a second-look procedure reserved for cases in which conventional reduction either fails or raises suspicion of an underlying lesion.

What the endoscopes found was striking. In 31 of the 63 children, nearly half, colonoscopy revealed an abnormality plausibly responsible for the intussusception. The single most common finding was the juvenile polyp, a benign but bulky hamartomatous growth of the colonic mucosa, identified in 23 children. Five children were diagnosed with Peutz-Jeghers syndrome, a rare genetic condition characterized by multiple hamartomatous polyps throughout the gastrointestinal tract and distinctive dark pigmentation of the lips and mouth. Two children turned out to have Burkitt’s lymphoma, an aggressive malignancy of the bowel that can present in the intestine as a mass capable of dragging the bowel wall into itself. A single child had an inflammatory mass. In other words, for roughly one child in two referred to colonoscopy, the intussusception was not an idiopathic event of early childhood but the visible symptom of a defined pathological lesion.

The therapeutic implications were equally significant. Among the 31 children with detected abnormalities, 24 underwent polypectomy through the colonoscope itself, and the team removed a total of 56 polyps. This means that for most of these patients, the diagnostic procedure and the definitive treatment were one and the same: the endoscopist identified the lead point, snared it, resected it, and in many cases retrieved it for histological examination, all without a surgical incision. Only a minority, including the children with Burkitt’s lymphoma, required onward management by other specialties, since a malignant infiltration of the bowel wall is not amenable to endoscopic resection. The study’s authors conclude that colonoscopy can play a genuine dual role, diagnostic and therapeutic, in secondary intussusception, and their numbers give that conclusion real quantitative weight.

To understand why this matters, it helps to consider the mechanics of the disease. Primary or idiopathic intussusception, which predominates in infants between roughly three months and three years of age, is thought to arise from enlarged lymphoid tissue in the terminal ileum, often after a viral infection, and it typically reduces successfully with enema and does not recur. Secondary intussusception is different. Here a discrete anatomical abnormality, a polyp, a tumor, an inverted Meckel’s diverticulum, or an inflamed patch of bowel, serves as the leading edge that gets propelled forward by peristalsis, pulling the adjoining segment with it. Because the lead point persists, air enema reduction may succeed temporarily but the intussusception recurs, or the enema fails outright because the lesion anchors the telescoped segment in place. Older children are disproportionately represented in this secondary group, which fits the study’s average patient age of nearly five and a half years, well beyond the typical idiopathic window.

Current international guidance has been ambivalent about endoscopy in this setting. Many pediatric surgery and radiology protocols recommend that children with recurrent intussusception, failure of nonoperative reduction, or an age atypical for idiopathic disease undergo further imaging, usually ultrasound or computed tomography, to search for a pathological lead point. Ultrasound is fast, noninvasive, and excellent at confirming the intussusception itself, but it is operator dependent and can miss small intraluminal polyps. Computed tomography offers better anatomical resolution but exposes children to ionizing radiation and still may not characterize the mucosal surface. Colonoscopy, by contrast, inspects the mucosa directly at high magnification and in real time, and, crucially, allows immediate intervention. The Chongqing data suggest that when the clinical picture points toward a secondary cause, colonoscopy deserves a more prominent and earlier position in the diagnostic pathway than it has traditionally occupied.

The safety profile of the approach is another important part of the story. Endoscopic polypectomy in children is an established technique, but performing it in a bowel segment that has recently been intussuscepted raises theoretical concerns about perforation, edema, and compromised tissue viability. The fact that 24 children in this series underwent endoscopic polypectomy without the series reporting widespread complications lends practical reassurance, although the retrospective design means the report is best read as an experience-based series rather than a controlled comparison. The authors obtained informed consent from parents or guardians for all participants, and the study was conducted under institutional ethics approval in line with the Declaration of Helsinki, reflecting the sensitivity of endoscopic intervention in a pediatric emergency context.

There are also broader lessons for practicing clinicians. A child who presents with intussusception after the age of three, who has had more than one episode, or who fails initial air enema reduction should prompt a search for a lead point rather than repeated enemas alone. The finding that five of 63 children in this cohort had Peutz-Jeghers syndrome is particularly noteworthy, because that diagnosis carries lifelong implications well beyond the acute episode: patients require regular surveillance endoscopy for polyp burden and carry elevated cancer risk that mandates structured follow-up into adulthood. Similarly, the two cases of Burkitt’s lymphoma underscore that intussusception can be the first manifestation of a life-threatening malignancy, and that the histological examination of any resected lead point is not a formality but a critical diagnostic step that may redirect the entire course of care.

Limitations of the study are worth keeping in view. As a single-center retrospective analysis, it cannot establish how frequently secondary intussusception occurs across the wider population, nor can it define the optimal timing of colonoscopy relative to enema attempts. The 63 children represent a selected group in whom endoscopy was already deemed appropriate, so the near-50 percent yield of abnormalities should not be extrapolated to all children with intussusception, most of whom will never need a scope. Selection bias likely inflates the detection rate relative to an unselected cohort, and the authors did not report long-term recurrence outcomes after polypectomy, which would be the ultimate test of whether removing the lead point prevents future episodes.

Even with those caveats, the study adds meaningful evidence to a long-standing clinical debate. It demonstrates, in a substantial pediatric cohort and across nearly a decade of practice, that colonoscopy is both feasible and frequently decisive in children whose intussusception is suspected to be secondary. For the 24 children spared an open operation, and for the families who left the hospital with a specific diagnosis rather than a mystery, the flexible scope did what it does best in modern medicine: it looked directly at the disease and, in the same sitting, removed it. As pediatric centers refine their protocols for recurrent and atypical intussusception, this work makes a strong case that the colonoscope should no longer be an afterthought but a planned, early step in the evaluation of the child whose bowel keeps telescoping for reasons the enema cannot explain.

Subject of Research: The use of colonoscopy to diagnose and treat secondary intussusception in children

Article Title: Colonoscopy in the diagnosis and treatment of secondary intussusception

Article References: Hou, J., Cao, F., Cui, M., Wang, Y., Liu, W., Feng, W., & Guo, Z. (2026). Colonoscopy in the diagnosis and treatment of secondary intussusception. BMC Pediatrics. https://doi.org/10.1186/s12887-026-07636-2

Image Credits: AI Generated

DOI: 10.1186/s12887-026-07636-2

Keywords: intussusception, colonoscopy, pediatrics, juvenile polyps, Peutz-Jeghers syndrome, Burkitt's lymphoma, endoscopy, air enema, polypectomy, children's hospital, intestinal obstruction, diagnosis