The Current Look of MAC in a Large Multihospital System. (21st September 2018)

• Record Type: Journal Article
• Authors: Mahabir, Roshan; Ravirala, Sushma; Matloob, Ammar; Van Denakker, Tayler; Zeizafoun, Nebras
• Is Part Of: American journal of clinical pathology. Volume 150(2018)Supplement 1
• Page Start: S136
• Page End: S136
• Publication Date: 2018-09-21
• Subjects: Diagnosis, Laboratory -- Periodicals; Pathology -- Periodicals; 616.07
• DOI: 10.1093/ajcp/aqy104.325
• Languages: English
• ISSNs: 0002-9173

Abstract

Abstract: Objectives: Mycobacterium avium complex (MAC) is an opportunistic infection caused by the nontuberculous mycobacteria group of organisms; diagnosis is made based on clinical correlation, histology, and immunohistochemistry. Usually diagnosed in patients with severely compromised immune systems, it is now rarely seen. Due to the widespread use of antiretroviral therapy (ART), the current epidemiology of MAC remains to be determined. Methods: A 10-year retrospective study (2007-2017) was conducted using the pathology database search for all MAC cases within our system. The biopsy cases were evaluated for clinicopathological parameters: site of occurrence, presenting symptoms, clinical suspicion, and demographics. Results: Thirty-one cases were identified, with one autopsy of a 79-year-old man with disseminated MAC in multiple lymph nodes due to immunosuppression from DM and myelodysplastic syndrome (MDS). Of the 30 biopsy-proven MAC cases, there was a slight male to female predominance (1:1.1) and an average age of 39.2 (26–57) years but an earlier occurrence in females (females, 37.4 years vs males, 40.8 years). The most common presenting complaint was infectious (55.8%) (diarrhea, 50.0%; fever or gastroduodenitis, 16.7% each; Candida, 8.3%; weight loss or syphilis, 4.2% each) or malignancy (34.9%) (mass/carcinoma, 33.3%; lymphadenopathy and lymphoma, 26.7% each; anemia and pancytopenia, 6.7% each). Of the cases where the clinical suspicion was lymphoma, the patient presented with fever (2/5), lymphadenopathy (2/5), or weight loss (1/5). MAC was identified in biopsies from the small bowel (60.9%), large bowel (26.1%), bone marrow (8.7%), and skin (4.3%). Of the lymph nodes biopsied, 42.9% were mesenteric, 28.6% were para-aortic supraclavicular, and abdominal were 14.3% each. Conclusion: Even though MAC can be associated with any immunosuppression, it is mostly related to HIV/AIDS with a male predominance yet presents earlier in females. It is usually associated with infectious diseases but can be found in the clinical suspicion of malignancy and carcinoma, even though not suspected.