S1767 Disseminated Mycobacterium avium Complex Ileitis, Duodenitis, and Pancolitis in an Immunocompromised Patient With HIV/AIDS

Abstract

INTRODUCTION: Patients with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) are at increased risk of opportunistic infections such as Mycobacterium Avium Complex (MAC); this rarely involves the gastrointestinal (GI) tract. Noncompliance with antiretroviral therapy (ART) increases susceptibility. We herein present a young female with HIV/AIDS and disseminated MAC noncompliant with antiretroviral therapy presenting with watery diarrhea and abdominal pain, ultimately diagnosed with MAC duodenitis, ileitis and pancolitis with unique endoscopic findings. CASE DESCRIPTION/METHODS: A 26-year-old female with history of congenital HIV/AIDS on ART (though poorly compliant), disseminated MAC, genital herpes simplex virus (HSV), and oral thrush presented with generalized cramping abdominal pain and watery diarrhea for three weeks. On admission, she was tachycardic and mildly hypotensive. Physical exam revealed a thin female with mild diffuse abdominal tenderness and genital and perianal ulcerations. Labs showed pancytopenia with white blood cell count 2.45 10 × 3 uL, hemoglobin 8 g/dL and platelet count 56 10*3 uL. Absolute CD4 cell count was 2 uL and HIV RNA PCR over 3 million copies/ml. GI PCR panel and Clostridioides difficile testing were negative. Cytomegalovirus PCR was negative. Sputum Mycobacterium PCR confirmed MAC. Computed tomography abdomen/pelvis showed pancolitis without terminal ileum involvement. Treatment was initiated with intravenous piperacillin/tazobactam, micafungin, and acyclovir while continuing azithromycin, ethambutol and rifabutin for disseminated MAC in the setting of HIV/AIDS. Esophagogastroduodenoscopy showed esophageal, gastric and duodenal ulcerations. Colonoscopy showed severely congested mucosa with scattered areas of nodularity and ulceration (Figure 1) throughout the entire colon and examined terminal ileum. Gastric, duodenal, ileal and colonic biopsies were notable for acid-fast bacilli, consistent with known history of disseminated MAC (Figures 2 and 3). Her prognosis remains guarded given comorbidities and overall poor compliance with therapy. DISCUSSION: Although MAC is a common opportunistic infection seen in immunocompromised hosts, colonic and small bowel dissemination has rarely been reported. The diagnosis may be missed, as the clinical manifestations may be nonspecific. This case highlights the importance of including MAC in the differential of an immunocompromised patient presenting with GI manifestations.Figure 1.: Colon with diffuse areas of severely congested mucosa, scattered nodularity, and ulcerations.Figure 2.: Prominent lamina propria expansion by foamy histiocytes within the mucosa and villi of the ileum with notable absence of distended lacteals, characteristic of Mycobacterium Avium Complex (H&E stain, 100x).Figure 3.: AFB stain highlights acid-fast bacilli within foamy macrophages (AFB stain, 600x).