Incidence, Clinical Manifestation, Treatment Outcome, and Drug Susceptibility Pattern of Nontuberculous Mycobacteria in HIV Patients in Tehran, Iran

Abstract

BACKGROUND: Non tuberculous mycobacterial (NTM)infections have radically increased worldwide due to the increasein HIV infections. The disease activity increases with progressiveimmunodeficiency.

METHODS: A total of 216 HIV seropositive patients suspectedof having mycobacterial infection were recruited for this study.Clinical samples were collected from each patient and culturedon Lowenstein-Jensen media. Detection and speciesidentification were simultaneously done using Reverse BlotHybridization Assay System. Also, the minimum inhibitoryconcentrations (MIC) for each isolate were determined in 7H9broth media for 10 antibiotics.

RESULTS: In this study, 4 rapid and 4 slow-growing NTMspecies were isolated and identified. Mycobacterium fortuitumwas the most common NTM species, 3/8 (37.5%), followed byMycobacterium kansasii, 2/8 (25%). The cases were identified aspulmonary disease, 5/8 (62.5 %), disseminated infection, 2/8(25%), and skin abscess, 1/8 (12.5%). M. chelonae and Mycobacterium avium were isolated from patients diagnosedwith disseminated infection with treatment failure. The skinabscess was caused by infection with M. simiae. The results ofthe MIC testing were as follows: M. kansasii and M. fortuitumwere susceptible to amikacin (AMK); M. avium toclarithromycin (CLA); M. fortuitum 2/3 (67%) to ciprofloxacin(CIP); 1/2 (50%) of M. kansasii isolates to CLA, and M.chelonae to rifampin (RIF), linezolid (LIN), AMK, and CIP atmedium and high concentrations.

CONCLUSION: AMK showed incredible in vitro activity againstM. kansasii and M. fortuitum. Also, M. avium was susceptible toCLA, whereas M. simiae and M. chelonae were resistant to thetested drugs in this study.