Iron deficiency anemia is the most prevalent nutritional anemia in children across the globe, and pediatricians encounter it daily. The standard diagnostic playbook is well rehearsed: assess dietary iron intake, screen for hereditary conditions such as thalassemia or sickle cell disease, look for overt or occult blood loss, and consider impaired absorption. In this patient, the workup initially revealed a classic microcytic, hypochromic pattern on his complete blood count — red cells that were both smaller and paler than normal, with a reduced mean corpuscular hemoglobin — alongside biochemical markers confirming genuine iron depletion. His diet was adequate, and there was no family history to suggest an inherited anemia. That left the uncomfortable question of where his iron was going.

The answer, it turned out, was seeping away invisibly. Upper gastrointestinal endoscopy revealed ulcers in both the stomach and the duodenum, accompanied by H. pylori-associated gastritis. Chronic oozing from these lesions, too slow to ever produce visible blood in the stool, had been draining the boy’s iron reserves for months. The bacteria itself was confirmed with a carbon-13 urea breath test, a noninvasive diagnostic in which the patient ingests urea labeled with a stable isotope; H. pylori’s urease enzyme splits the urea, releasing labeled carbon dioxide that can be measured in exhaled breath. A positive result, combined with the endoscopic picture, gave the team a coherent etiological story: infection, ulceration, occult bleeding, and iron loss.

What makes the case striking is the complete absence of gastrointestinal symptoms. Peptic ulcer disease in adults typically announces itself with epigastric pain, often related to meals, and children are generally assumed to present similarly. This patient felt nothing in his abdomen. The authors of the report emphasize that this silence delayed consideration of gastrointestinal pathology altogether, a delay they argue is not merely anecdotal but representative of a broader blind spot in clinical practice, particularly in regions where H. pylori prevalence is high.

The biology behind this presentation is well characterized even when the clinical presentation is not. H. pylori colonizes the gastric mucosa, where it disrupts the protective mucus layer, triggers chronic inflammation, and can cause erosions and ulcers. At the same time, the organism competes directly with its host for iron: it expresses receptors that bind human lactoferrin and other iron-containing proteins, effectively pirating the micronutrient for its own metabolism. Chronic gastritis can also reduce gastric acid output and ascorbic acid levels, both of which are needed to convert dietary ferric iron into the ferrous form that the duodenum absorbs. The result is a double hit — ongoing blood loss plus impaired iron uptake — that can outpace any dietary compensation.

In children, the stakes of missing this diagnosis compound over time. Iron is essential not only for hemoglobin synthesis but for neurocognitive development, immune function, and physical growth. Prolonged deficiency during school-age years has been associated with fatigue, reduced exercise tolerance, and difficulties with concentration. An ulcer that goes untreated, meanwhile, carries risks of its own, including more significant hemorrhage, perforation, and scarring. Early identification of H. pylori as the driver therefore converts a potentially progressive, insidious illness into a readily reversible one: eradication therapy combining antibiotics with a proton pump inhibitor, followed by confirmation of cure, typically resolves both the infection and its hematological consequences.

The report’s authors, a team of pediatricians and gastroenterologists affiliated with hospitals in Jiashan, Shanghai, and Hangzhou, argue that refractory or unexplained iron deficiency anemia in children should prompt clinicians to look beyond the usual suspects. Even in the absence of abdominal pain, they recommend that H. pylori infection and peptic ulcer disease enter the differential diagnosis once dietary inadequacy, hereditary anemias, and other common causes of iron loss have been excluded. Noninvasive testing such as the urea breath test makes this a practical proposition even in primary care settings, though definitive characterization of mucosal disease still requires endoscopy.

The epidemiological backdrop gives the recommendation added urgency. H. pylori infects roughly half of the world’s population, with prevalence substantially higher in developing regions and in communities with crowded living conditions and limited sanitation. Most infected individuals never develop symptomatic disease, which is precisely what makes the infection so easy to overlook when it does cause harm. In pediatrics, where complaints are often vague and children may not articulate discomfort clearly, an asymptomatic presentation is less an anomaly than a hazard baked into the disease’s natural history.

There is also a lesson here about the limits of symptom-driven medicine. The traditional diagnostic heuristic — follow the patient’s complaints — works well for acute conditions but can fail for slow-burning processes that announce themselves only through laboratory abnormalities. A hemogram showing microcytic anemia is not a diagnosis; it is a question. In this case, answering that question required the clinical team to resist the reassuring absence of symptoms and pursue invasive and noninvasive testing until the source of iron loss was found. The boy’s pallor and fatigue were, in effect, the surface expression of a subterranean hemorrhage.

For clinicians, the takeaway is concrete: in a child with iron deficiency anemia that does not respond as expected to iron supplementation, or in which no dietary or hereditary explanation exists, testing for H. pylori deserves a place early in the workup rather than as a last resort. For parents, the message is subtler but no less important — persistent pallor and fatigue in a child warrant medical evaluation even when the child insists he feels fine. A bacterium as widespread and as quiet as H. pylori does not always announce its presence; sometimes the only evidence it leaves behind is in the blood count.

Subject of Research: Helicobacter pylori-related peptic ulcer disease presenting as isolated iron deficiency anemia in a child

Article Title: Helicobacter pylori-related peptic ulcer presenting as isolated iron deficiency anemia without typical gastrointestinal complaints in a child: a case report

Article References: Chen, X., Miao, S., Zou, S., Wang, Y., Chen, G., & Jiang, M. (2026). Helicobacter pylori-related peptic ulcer presenting as isolated iron deficiency anemia without typical gastrointestinal complaints in a child: a case report. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14366-4

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14366-4

Keywords: Helicobacter pylori, iron deficiency anemia, peptic ulcer, pediatrics, endoscopy, urea breath test, gastrointestinal bleeding, anemia, gastritis, case report, occult blood loss, BMC Infectious Diseases