Celiac Disease Spectrum Among Patients With Iron Deficiency Anemia: A Retrospective Study From a Tertiary Care Center in Morocco

Background Celiac disease is a chronic immune-mediated enteropathy triggered by gluten in genetically susceptible individuals. Its presentation is variable and may range from classic malabsorptive symptoms to atypical or extraintestinal manifestations. Iron deficiency anemia (IDA) is a common extraintestinal presentation and may occur without gastrointestinal symptoms, which can delay diagnosis. Objective To determine the hospital-based proportion of celiac disease among patients with iron deficiency anemia at Cheikh Khalifa International University Hospital, Casablanca, Morocco, and to describe their clinical, biological, serological, and histological characteristics. Methods We conducted a retrospective, descriptive, single-center study of patients with IDA followed in the Department of Medical Hematology between January 2020 and September 2025. Among 635 patients with IDA, 97 underwent anti-tissue transglutaminase IgA (anti-tTG IgA) testing, and 40 underwent duodenal biopsy based on clinical suspicion. Celiac disease was confirmed by positive anti-tTG IgA serology and compatible duodenal histology. One patient with strongly positive serology and normal histology was classified as having potential celiac disease according to the Oslo definitions. Data were collected retrospectively from medical records and hospital databases. Results Among the 635 patients with IDA, 97 underwent serological testing, of whom 18 were positive, while 40 underwent duodenal biopsy. Seventeen patients had biopsy-confirmed celiac disease, and one additional patient was classified as having potential celiac disease, resulting in an 18-patient celiac disease spectrum cohort and a crude hospital-based proportion of 2.83%. This figure reflects selective, clinically driven testing and should not be extrapolated to the general population or to unselected patients with IDA. All 18 patients were female, with a mean age of 29.9 years. Asthenia was reported in all patients, and intestinal discomfort was the most frequent digestive symptom (83.3%). Weight loss, chronic diarrhea, and steatorrhea were reported in 66.6%, 44.4%, and 27.7% of patients, respectively. Extra-intestinal manifestations included arthralgia (38.9%), bone pain (27.7%), oral aphthous ulcers (11.1%), amenorrhea (22.2%), and recurrent miscarriage (16.7%). Mean hemoglobin was 9.9 ± 1.4 g/dL, and 94.4% of patients had ferritin levels below 15 ng/mL. Among the nine patients assessed for micronutrient status, folate and vitamin D deficiencies were found in 44.4% and 66.7%, respectively. Anti-tTG IgA was positive in all 18 patients, and Marsh III lesions were found in 66.6% of cases. Gastritis and Helicobacter pylori infection were each identified in approximately half of the patients who underwent upper endoscopy. All patients started a gluten-free diet; 12 received oral iron supplementation, and six received intravenous iron. Conclusion Celiac disease may be an underrecognized cause of iron deficiency anemia in this single-center hospital cohort, particularly among young women. Celiac serology should be considered in the evaluation of unexplained or persistent IDA, including in patients without overt gastrointestinal symptoms, to facilitate earlier diagnosis and appropriate nutritional management.