Profound Iron Deficiency Anemia Associated With Endoscopically Visualized Nematode Infestation Mimicking Gastric Malignancy: A Case Report From Trinidad and Tobago.

Severe iron deficiency anemia (IDA) secondary to parasitic infestation is uncommon in modern clinical practice but remains an important diagnostic consideration in endemic regions and vulnerable populations. We present the case of a 61-year-old male patient who presented to the emergency department following a syncopal episode and fall and was found to have profound anemia with an initial hemoglobin level of 2.5 g/dL and a serum ferritin of 1.96 ng/ml. Initial diagnostic workup with contrast-enhanced computed tomography of the abdomen and pelvis excluded acute intra-abdominal hemorrhage but demonstrated marked thickening of the gastric fundus and body, raising concern for an underlying gastric malignancy. Laboratory investigations additionally revealed raised eosinophil percentage on complete blood count analysis. Following hemodynamic stabilization and packed red blood cell transfusion, the patient underwent esophagogastroduodenoscopy. Endoscopic evaluation revealed short-segment Barrett's esophagus (Prague classification C0M2) and multiple motile nematodes attached to the duodenal mucosa, consistent with an endoscopically visualized nematode infestation involving the proximal small bowel. In the context of endemic exposure, raised eosinophil percentage, profound microcytic anemia, and low ferritin, this was considered morphologically suggestive of hookworm infestation. Further dietary and social history revealed habitual barefoot outdoor exposure and regular consumption of wild meat, supporting environmental risk factors for parasitic infection. Stool microscopy was negative, and histopathology did not identify parasitic organisms or malignancy. The patient was treated with albendazole and proton pump inhibitor therapy, with subsequent clinical improvement, recovery of hemoglobin levels following transfusion and anti-helminthic treatment, and sustained hematologic stability on follow-up. This case highlights the importance of considering parasitic infection in the differential diagnosis of severe microcytic anemia and gastric wall thickening, particularly in endemic settings. It also demonstrates how infectious gastrointestinal pathology may mimic advanced malignancy on cross-sectional imaging.