Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda; TB Unit, Department of Bacteriology, Swedish Institute for Infectious Disease Control, SE-171 82 Solna, Sweden; Department of Microbiology, Tumour and Cell Biology, Karolinska Institute, Stockholm, Sweden
Bwanga, F., Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda, TB Unit, Department of Bacteriology, Swedish Institute for Infectious Disease Control, SE-171 82 Solna, Sweden, Department of Microbiology, Tumour and Cell Biology, Karolinska Institute, Stockholm, Sweden; Joloba, M.L., Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda; Haile, M., TB Unit, Department of Bacteriology, Swedish Institute for Infectious Disease Control, SE-171 82 Solna, Sweden, Department of Microbiology, Tumour and Cell Biology, Karolinska Institute, Stockholm, Sweden; Hoffner, S., TB Unit, Department of Bacteriology, Swedish Institute for Infectious Disease Control, SE-171 82 Solna, Sweden, Department of Microbiology, Tumour and Cell Biology, Karolinska Institute, Stockholm, Sweden
SETTINGS: National Tuberculosis (TB) Reference Laboratory and Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda. OBJECTIVE: To evaluate head-to-head rapid tests for drug susceptibility testing (DST) of Mycobacterium tuberculosis against rifampicin (RMP) and isoniazid (INH) in a resource-limited setting. METHODS: Thirty-one well-characterised strains of M. tuberculosis were tested with the nitrate reductase assay (NRA), microscopic observation drug susceptibility (MODS), MGITTM 960 (Mycobacterium Growth Indicator Tube 960), Genotype® MTBDRplus, Alamar blue, MTT and resazurin assays. The proportion method on Löwenstein-Jensen medium was used as the reference test. RESULTS: NRA correctly identifi ed the resistant strains, with 100% sensitivity and specifi city. MGIT 960 detected all multidrug-resistant strains but missed one RMPmonoresistant strain. Genotype MTBDRplus detected all RMP-resistant strains, but the sensitivity for detection of INH resistance was lower (88%). Sensitivity and specifi city ranged from 86% to 100% for MODS and from 57% to 100% for the Alamar blue, MTT and resazurin assays. Test results were obtained within 2-14 days. CONCLUSION: In the study setting, NRA, MGIT 960 and Genotype MTBDRplus gave excellent detection of multidrug-resistant tuberculosis, with signifi cantly shorter time to results compared to conventional testing. © 2010 The Union.
3 (4,5 dimethyl 2 thiazolyl) 2,5 diphenyltetrazolium bromide; isoniazid; nitrate reductase; resazurin; rifampicin; isoniazid; rifampicin; tuberculostatic agent; article; assay; bacterial growth; bacterial strain; bacterium detection; bacterium isolate; bacterium isolation; colorimetry; controlled study; culture medium; drug resistant tuberculosis; drug sensitivity; enzyme assay; genotype; human; lung tuberculosis; microscopic observation drug susceptibility; microscopy; multidrug resistance; mycobacterium growth indicator tube 960; Mycobacterium tuberculosis; nitrate reductase assay; nonhuman; observation; priority journal; sensitivity and specificity; Uganda; comparative study; drug effects; isolation and purification; microbial sensitivity test; microbiology; Mycobacterium tuberculosis; time; Tuberculosis, Multidrug-Resistant; Antitubercular Agents; Humans; Isoniazid; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Rifampin; Sensitivity and Specificity; Time Factors; Tuberculosis, Multidrug-Resistant; Uganda