Abstract A 28-year-old woman presented with chronic diarrhea, weight loss, and recurrent gastrointestinal infections. Intestinal biopsies unexpectedly revealed Histoplasma capsulatum , prompting immunologic evaluation that demonstrated severe hypogammaglobulinemia and reduced B-cell counts, consistent with common variable immunodeficiency. She improved with intravenous immunoglobulin and antifungal therapy. This case highlights gastrointestinal histoplasmosis as a potential early marker of undiagnosed common variable immunodeficiency and underscores the importance of considering primary immunodeficiency in adults with persistent gastrointestinal symptoms.
Oliva et al. (Sun,) studied this question.