1177. Treatment Non-adherance Resulting in Development of Macrolide-resistant Disseminated Mycobacterium avium complex Infection in Advanced HIV Patients
Session: Poster Abstract Session: Mycobacteria Other Than Tuberculosis
Saturday, October 22, 2011
Room: Poster Hall B1

Disseminated Mycobacterium avium complex (MAC) is a common opportunistic infection in patients with late-stage HIV.  Macrolides are recognized as the cornerstone of treating disseminated MAC (DMAC). However, MAC is resistant to macrolides in a minority of patients with poor outcome. The purpose of the study is to examine the characteristics of patients with macrolide-resistant DMAC (MR-DMAC).


Cases of MR-DMAC from 2008-2009 were identified from the microbiology database of Grady Memorial Hospital. Macrolide-resistance (MR) was proven in all cases by drug sensitivity testing. A retrospective medical chart review was performed for all cases.


During the study period, 21 patients had susceptibility testing results available, and nine (42%) patients were found to have MR. One patient was excluded as the records were not available for review. The remaining eight patients were all male, HIV positive with a median CD4 count of 23 (range 4-52), and median age of 37.5 (range 24-45) at the time of MR-DMAC diagnosis. The median time from diagnosis of DMAC to MR-DMAC was 13 months (range 0-23). All had history of macrolide exposure prior to the diagnosis of MR-DMAC either as DMAC prophylaxis or treatment. Of the five patients who had information available on treatment compliance, all except for one were non-compliant, and the one compliant patient was kept on macrolide-based regimen after the diagnosis of MR-DMAC. Two patients had documented clearance of AFB blood cultures prior to diagnosis of MR, however, both patients were symptomatic around the time of documented clearance and later relapsed. Deaths from DMAC occurred at a median of 3 months (range 3-8) in three patients, and four were lost to follow up at a median of 13.5 months (range 5-16). All three patients whose deaths were documented died from a cause related to DMAC. 


MR-DMAC has a poor prognosis in advanced AIDS patients and likely develops as a result of non-adherence to macrolide prophylaxis or treatment. More than one AFB blood culture may be needed when signs and symptoms of DMAC are present in advanced AIDS patients on DMAC treatment, and susceptibility testing should promptly be performed if a patient is persistently bacteremic on treatment.

Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Miwako Kobayashi, MD, MPH, Daniel Livorsi, MD, Minh Ly Nguyen, MD, MPH and Melissa Osborn, MD, Emory University School of Medicine, Atlanta, GA


M. Kobayashi, None

D. Livorsi, None

M. L. Nguyen, None

M. Osborn, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.