University of Texas Health Science Center at San Antonio San Antonio, TX, United States
Sanjay Prasad, MD1, Brenda Briones, MD2, Pranav Penninti, DO1, Kenneth T. Hughes, MD1, Patrick Snyder, MD2 1University of Texas Health Science Center at San Antonio, San Antonio, TX; 2UT Health San Antonio, San Antonio, TX
Introduction: Disseminated Mycobacterium avium complex (MAC) is an uncommon cause of gastrointestinal disease typically occurring in profoundly immunosuppressed individuals and presenting with non-specific symptoms and endoscopic findings. We present a patient with disseminated MAC and the unusual finding of a perforated duodenal ulcer.
Case Description/Methods: A 44 year old male with HIV and AIDS (CD4 < 40) presented with one month of diarrhea, generalized weakness, poor appetite and weight loss. Chest imaging revealed bilateral cavitary pulmonary nodules, and bronchoscopy with bronchoalveolar lavage and endobronchial biopsies confirmed the presence of numerous acid-fast bacilli with cultures eventually isolating MAC. Initial stool studies were unremarkable. Colonoscopy showed mildly congested and edematous mucosa throughout the colon with biopsies revealing innumerable acid-fast bacilli laden macrophages in the lamina propria, compatible with MAC colitis (1). One day later, he experienced acute epigastric pain and melena, prompting an upper endoscopy that showed a 20 mm cratered duodenal ulcer with evidence of perforation and visible omentum (2,3). Biopsies were deferred in this setting. Unfortunately, he was deemed a poor surgical candidate and was treated conservatively and eventually transitioned to comfort care.
Discussion: This case exhibits an unusual manifestation of disseminated MAC in the form of a perforated duodenal ulcer. While histologic proof of MAC duodenitis and ulceration is lacking, this diagnosis seems most likely given cytologic, culture and histologic evidence of MAC in the lungs and colon, an absence of recent NSAID use and negative studies for Histoplasma and Mycobacterium tuberculosis. Nonetheless, peptic ulcer disease, disseminated histoplasmosis or tuberculosis, lymphoma and Whipple’s disease remain on the differential diagnosis. GI tract involvement is common in disseminated MAC, with the duodenum being the most frequently affected site. MAC infiltrates the GI tract by adhering to mucosal epithelial cells and phagocytosis by resident macrophages. Endoscopic findings in gastrointestinal MAC are non-specific. There are isolated case reports of small bowel obstruction, peritonitis, and ileal perforation caused by MAC infection, but duodenal ulceration with perforation is a novel presentation. Disseminated MAC should be considered in unexplained gastrointestinal disease including ulceration in immunosuppressed patients.
Figure: 1. Ziehl-Neelsen stain (400x magnification) shows innumerable acid-fast bacilli filling lamina propria macrophages in otherwise normal colonic mucosa 2/3. 20 mm cratered duodenal ulcer with evidence of perforation and visible omentum
Sanjay Prasad indicated no relevant financial relationships.
Brenda Briones indicated no relevant financial relationships.
Pranav Penninti indicated no relevant financial relationships.
Kenneth Hughes indicated no relevant financial relationships.
Patrick Snyder indicated no relevant financial relationships.
Sanjay Prasad, MD1, Brenda Briones, MD2, Pranav Penninti, DO1, Kenneth T. Hughes, MD1, Patrick Snyder, MD2. P0952 - Perforated Duodenal Ulcer Secondary to Disseminated MAC, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.