RESUMO
Streptomycin (STR) and ethambutol (EMB) are important drugs used for the treatment of tuberculosis. There is a need for fast, reliable and inexpensive methods for detecting resistance to these drugs. The aim of this study was to evaluate the performance of the crystal violet decolorization assay (CVDA) for the detection of STR and EMB resistance that is important drugs in tuberculosis treatment. In this study, drug susceptibility testing was performed on 140 Mycobacterium tuberculosis isolates provided from nine centers. Three tubes were used for each isolate. One of the tubes had a concentration of 2 mg/L STR and the other 5 mg/L EMB. The third was drug-free control tube. Sensitivity, specificity, positive predictive value (PPD), negative predictive value (NPD) and agreement for STR were found to be 81.8%, 94.6%, 87.8%, 91.5% and 90.57%, respectively. For EMB, sensitivity, specificity, PPD, NPD, and agreement were found to be 76%, 98.23%, 90.47%, 94.87% and 94.2%, respectively. The results were obtained in 11.3 ± 2.7 days (8-21 days). CVDA is rapid, reliable, inexpensive, and easy to perform for rapid detection of STR and EMB resistance, and it could be adapted for drug susceptibility testing.
Assuntos
Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana/métodos , Colorimetria/métodos , Etambutol/farmacologia , Mycobacterium tuberculosis/isolamento & purificação , Estreptomicina/farmacologia , Farmacorresistência Bacteriana , Violeta Genciana/química , Humanos , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologiaRESUMO
The incidence of human tuberculosis (TB) disease due to Mycobacterium caprae, an etiologic agent of zoonotic TB along with Mycobacterium bovis, is very low. There are no guidelines for human TB caused by M. caprae, and treatment protocols for infections caused by this microorganism are based on the recommendations for M. bovis infections. We report a 15-year-old girl diagnosed with cervical lymphadenitis due to M. caprae. She did not recover completely despite 6 months of anti-TB medication. Therefore, treatment was extended to 12 months. There is a lack of information about the treatment of human M. caprae infections. Further studies evaluating the treatment in detail are needed.
Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Feminino , Humanos , Adolescente , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Incidência , Progressão da DoençaRESUMO
Resistances to anti-tuberculosis (TB) drugs are related to the mutations in the genome of the Mycobacterium tuberculosis complex (MTBC). To expose the genomic mutations that cause anti-TB drug resistance. The GenoType MTBDRplus and MTBDRsl assays were used to detect genetic mutations. In this study of 1329 MTBC isolates, the sensitivities and specificities of genotypic methods for the detection of isoniazid (INH), rifampicin (RIF), ethambutol (EMB), and multi-drug resistance were 0.77, 0.84, 0.65, 0.89 and 0.99, 0.98, 0.67, 0.94, respectively. MUT3 mutations (S531L) of the rpoB gene for RIF resistance and MUT1 mutations (S315T1 and C15T) of the katG and inhA genes for INH resistance were dominant. The most frequently observed mutations that created resistance to fluoroquinolones (FLQ) were MUT3C (D94G) of the gyrA gene. The predominant mutations of EMB resistance were MUT1B (M306V) of the embB gene. Aminoglycosides/cyclic peptides (AG/CP) resistance was rare. The molecular mechanisms of anti-TB drugs resistance in MTBC strains found in Istanbul are similar to those in the literature.
Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/genética , Adulto , Aminoglicosídeos/farmacologia , Etambutol/farmacologia , Feminino , Fluoroquinolonas/farmacologia , Genótipo , Humanos , Isoniazida/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fenótipo , Rifampina/farmacologia , Turquia/epidemiologiaRESUMO
The aim of this multicenter study was to evaluate the performance of the crystal violet decolorization assay (CVDA) for detection of multidrug resistant tuberculosis (MDR-TB). This study was performed in 11 centers in two phases. A total of 156 isolates were tested for INH and RIF resistance. In the phase I, 106 clinical isolates were tested in the Center 1-7. In the phase 2, 156 clinical isolates were tested in the center 1-6, center 8-11. Eighty six of 156 tested isolates were the same in phase I. Agreements were 96.2-96.8% for INH and 98.1-98.7% for RIF in the phase I-II, respectively. Mean time to obtain the results in the phase I was 14.3 ± 5.4 days. In the phase II, mean time to obtain the results was 11.6 ± 3.5 days. Test results were obtained within 14days for 62.3% (66/106) of isolates in the phase I and 81.4% (127/156) of isolates in the phase II. In conclusion, CVDA is rapid, reliable, inexpensive, and easy to perform for rapid detection of MDR-TB isolates. In addition, it could be adapted for drug susceptibility testing with all drugs both in developed and developing countries.