1992 Hematochezia? Think Histoplasmosis

Abstract

INTRODUCTION: Histoplasmosis is the most common mycosis in North America, responsible for more hospitalizations and deaths than any other endemic mycosis in the United States. While it most commonly presents with pulmonary manifestations, we present a case of a 68-year-old female with history of renal transplantation who was transferred to our tertiary-care hospital with hematochezia, abdominal cramping, and emesis. CASE DESCRIPTION/METHODS: A 68-year-old female with history of renal transplant on immunosuppressive medications was transferred to our tertiary-care hospital with hematochezia. Prior to arrival at our hospital, she was transfused with 2 units of packed red blood cells for a hemoglobin of 5.3 g/dL. A diagnostic nasogastric lavage was negative. She underwent a colonoscopy which did not reveal active bleeding, however the mucosa throughout the entire colon was abnormal, described as nodular with focal areas of blanching and hemorrhagic appearance. The gross appearance was concerning for lymphoma, specifically posttransplant lymphoproliferative disease given her transplant history. As a result, she was transferred to our facility for further management. Chest CT revealed mesenteric and mediastinal lymphadenopathy as well as scattered calcified and noncalcified pulmonary micronodules. She had no pulmonary symptoms. Additional work up revealed a positive Histoplasma galactomannan urinary antigen. Additional staining of colonic biopsies revealed numerous histiocytes in the lamina propria with small round intracytoplasmic yeast microorganisms (GMS and PAS positive and mucicarmine negative) confirming the diagnosis of disseminated histoplasmosis. Patient was treated initially with a two-week course of amphotericin B before being transitioned to oral itraconazole. DISCUSSION: Disseminated histoplasmosis is most common in patients with a history of organ transplant, HIV or immunosuppressive medication regimen. T cell dysfunction accounts for a 10-fold higher risk for dissemination of histoplasmosis with nearly 1 in 2000 acute histoplasmosis infections becoming disseminated. Early diagnosis is the key to effective treatment. A simple urinary test can rule out the diagnosis and should be among one of the first steps in the workup of such patients. We propose clinicians maintain a high index of suspicion and that histoplasmosis be considered in patients with history of immunosuppression who present with acute onset bloody diarrhea with negative work-up for another intra-abdominal pathology.