In Vitro Antimicrobial Susceptibility of Nontuberculous Mycobacteria in Iran

Parvin Heidarieh, Mehdi Mirsaeidi, Mohamad Hashemzadeh, Mohamad Mehdi Feizabadi, Saeed Zaker Bostanabad, Mostafa Ghalami Nobar, Abodolrazagh Hashemi Shahraki

Research output: Contribution to journalArticlepeer-review

16 Scopus citations


Many species of nontuberculous mycobacteria (NTM) have long been identified as important causes of human disease, the incidence of which is rising. Several reports have suggested increasing trend of both in vitro and in vivo resistance to available treatment regimes. The aim of this study was to evaluate antibiotic susceptibility of clinically relevant NTM isolates using standard microbroth dilution test. Antimicrobial susceptibility testing was performed following National Committee for Clinical Laboratory Standards methods for NTM isolates, including 85 Mycobacterium fortuitum, 39 Mycobacterium chelonae, and 30 Mycobacterium abscessus subsp. abscessus as rapidly growing mycobacteria and 48 Mycobacterium simiae and 40 Mycobacterium kansasii as slowly growing mycobacteria. All isolates were recovered from various types of clinical samples and identified by multilocus sequence analysis. Trimethoprim-sulfamethoxazole (TMP-SMZ), amikacin, tobramycin, clarithromycin, moxifloxacin, linezolid, and imipenem showed better activity against M. fortuitum rather than meropenem, ciprofloxacin, cefoxitin, and doxycycline. Amikacin was active against 93% of M. abscessus subsp. abscessus. Linezolid, clarithromycin, cefoxitin, ciprofloxacin, imipenem, moxifloxacin, tobramycin, TMP-SMZ, doxycycline, and meropenem showed some activities on M. abscessus subsp. abscessus as well. The majority of M. abscessus subsp. abscessus and M. chelonae strains were multidrug resistant. Among the 40 isolates of M. kansasii, all were susceptible to ethambutol, isoniazid, clarithromycin, moxifloxacin, and linezolid. These isolates were also resistant to doxycycline and 50% were resistant to rifampicin and ciprofloxacin. M. simiae was resistant to clarithromycin, doxycycline, isoniazid, and TMP-SMZ, and the majority of isolates showed high levels of resistance to linezolid, ethambutol, ciprofloxacin, streptomycin, and rifampicin. The majority of M. simiae isolates were multidrug resistant. Our data confirm the need for performing of standard susceptibility testing of any clinically important NTM isolate.

Original languageEnglish (US)
Pages (from-to)172-178
Number of pages7
JournalMicrobial Drug Resistance
Issue number2
StatePublished - Mar 1 2016

ASJC Scopus subject areas

  • Microbiology
  • Immunology
  • Pharmacology
  • Microbiology (medical)


Dive into the research topics of 'In Vitro Antimicrobial Susceptibility of Nontuberculous Mycobacteria in Iran'. Together they form a unique fingerprint.

Cite this