Endoscopic and histopathologic findings in adults with iron deficiency anemia: the role of age

Iron deficiency anemia may signal underlying gastrointestinal pathology in adults. This study aimed to evaluate endoscopic and histopathological findings in adults undergoing upper gastrointestinal endoscopy and colonoscopy for iron deficiency anemia and to compare selected lesion frequencies between age groups. This retrospective study included 328 adult patients who underwent upper gastrointestinal endoscopy for iron deficiency anemia between January 2024 and December 2025; 285 also underwent colonoscopy. The mean age was 61.2 ± 14.8 years, and 62.5% of patients were male; 64.3% were older than 50 years. Pangastritis (30.5%) and antral gastritis (23.8%) were the most common upper gastrointestinal findings. Among biopsied patients, Helicobacter pylori positivity was 54.2%, intestinal metaplasia 14.6%, and atrophic gastritis 7.5%. On colonoscopy, hemorrhoids were most common (32.3%), followed by colonic polyps (24.6%); colorectal adenocarcinoma was found in eight patients (2.8%), all older than 50 years. Tubular adenoma with low-grade dysplasia was the most frequent polyp histopathology. Gastric polyps ( P = 0.013) and colonic polyps ( P = 0.041), which were not uniformly subclassified histologically, were significantly more frequent after age 50, whereas intestinal metaplasia ( P = 0.051) and colorectal cancer (8/190 vs. 0/95; P = 0.055) did not differ significantly between age groups. In this descriptive, single-group cohort, bidirectional endoscopy identified premalignant and malignant lesions in adults with iron deficiency anemia. As no nonanemic control group was included, these findings describe the diagnostic yield within this population and do not establish the clinical benefit of combined endoscopic evaluation.