Disseminated Histoplasmosis with Unusual Presentation in a Heart Transplant Recipient

A 45-year-old female, a known heart transplant recipient 14 years ago, presented to us with acute diarrhea which did not respond to empiric antibiotics and anti-protozoal medications. Lower gastrointestinal endoscopy showed multiple erosions with erythematous mucosa in the colon and rectum. Histopathology of colonic mucosal biopsy revealed lympho-histiocytic infiltrate and small fungal elements surrounded by a clear halo inside the histiocytes, which was consistent with Histoplasma capsulatum. Whole body positron emission tomography computerized tomography scan delineated a metabolically active cavitary lesion in the lower lobe of the right lung with mediastinal lymph nodes and foci of uptake in the D2 part of the duodenum and transverse colon. A diagnosis of disseminated histoplasmosis was made. The patient was treated with liposomal amphotericin B, following which her symptoms improved markedly, and she was discharged with itraconazole as “stepdown” therapy.