Aida Rezaie, MD, Faruq Pradhan, MD, Darrell Wadas, MD
University of Arizona College of Medicine, Phoenix, AZ
Introduction: Disseminated mycobacterium avium complex (MAC) is an uncommon diagnosis with the advent of highly active anti-retroviral therapy (HAART). The International Antiviral Society-USA Panel and the US Department of Health and Human services recently changed their guidelines recommending against routine MAC prophylaxis in patients on HAART. Gastrointestinal manifestations of MAC typically result in diarrhea, fever, weight loss, and abdominal pain. The diagnosis is clinically challenging as radiographic findings are non-specific and cultures can be negative for up to 2 weeks. Upper endoscopy with biopsy is required to make the diagnosis. We present a rare case of MAC colitis in a patient with AIDS with only focal subtle endoscopic changes.
Case Description/Methods: A 31-year-old male was admitted for fevers, chills, diarrhea and rectal pain for 1 week. The patient was diagnosed with HIV 1 year prior and declined HAART. On admission, the patient had a benign abdominal exam with tender inguinal lymphadenopathy. Computed tomography (CT) of the abdomen/pelvis without contrast demonstrated subtle wall thickening in the rectosigmoid consistent with proctocolitis. His absolute CD4 count was 38 cells/uL, unfortunately an HIV viral load was not checked. Stool culture with shiga toxin, clostridioides difficile, coccidioides, stool giardia/ova and parasites/cryptosporidium were negative. Cytomegalovirus (CMV) serum PCR was positive at 15,400 IU/mL. Colonoscopy showed normal mucosa throughout the colon and terminal ileum, except for a single, subtle, erosion of the rectum 2 mm in length. Biopsies taken of the solitary erosion were notable for acid fast bacilli concerning for intestinal MAC, CMV was negative. An interferon gamma release study was indeterminate. The patient was discharged on therapy for CMV viremia.
Discussion: The incidence of disseminated mycobacterium avium infection has decreased to 2 cases per 1000 person-years with the use of HAART. However, the risk of infection increases with high HIV viral loads > 1000 copies/mL, previous or concurrent opportunistic infections, and CD4 count < 50 cells/uL. Gastrointestinal MAC is rare, and when identified is most commonly found in the small bowel. Endoscopically, this is associated with granular, erythematous mucosa with ulcerations. Identification of the pathogen can be difficult unless direct biopsies of suspicious lesions are obtained on endoscopy.
Citation: Aida Rezaie, MD, Faruq Pradhan, MD, Darrell Wadas, MD. P0390 - MYCOBACTERIUM AVIUM COMPLEX COLITIS IN A PATIENT WITH AIDS. Program No. P0390. ACG 2019 Annual Scientific Meeting Abstracts. San Antonio, Texas: American College of Gastroenterology.