Gastritis colágena: una causa inusual de anemia en pacientes jóvenes

Collagenous gastritis (CG) is a rare condition that, in most cases, presents with severe iron-deficiency anemia or recurrent abdominal pain. It is characterized by increased collagen deposition in the subepithelial mucosa, associated with inflammatory infiltrates in the lamina propria. Similar histological findings can be observed in collagenous enterocolitis. The pathophysiology and prognosis of the disease are not yet fully understood, and clinical presentation may vary according to age group. This report describes a 15-year-old female patient referred by hematology for evaluation of chronic anemia, accompanied by asthenia, adynamia, pica, and abdominal pain. Esophagogastroduodenoscopy revealed severe mucosal alterations in the gastric body, and thorough pathological review confirmed the diagnosis of collagenous gastritis. Histologically observed collagen deposits may be related to a generalized disease affecting different areas of the gastrointestinal tract. In light of this case, a review of the available literature was conducted.