RESUMO
The emergence of multidrug-resistant tuberculosis (MDR-TB) is increasing and is exacerbated by the human immunodeficiency virus (HIV) epidemic. The standard short-course regimen used for the treatment of tuberculosis is likely to be ineffective against MDR-TB, leading to the need for second-line drugs. In such situations, drug susceptibility testing (DST) is necessary to select an appropriate treatment regimen. In this study, DST of 99 MDR-TB strains isolated in Thailand was performed using a drug-impregnated disc method. The results showed that 94.95% of the strains were susceptible to amikacin and kanamycin, 90.91% to ciprofloxacin and ofloxacin, 85.86% to para-aminosalicylic acid, and 78.79% to ethionamide.
Assuntos
Farmacorresistência Bacteriana Múltipla , Mycobacterium tuberculosis/efeitos dos fármacos , Amicacina/farmacologia , Ácido Aminossalicílico/farmacologia , Ciprofloxacina/farmacologia , Etionamida/farmacologia , Canamicina/farmacologia , Testes de Sensibilidade Microbiana/métodos , Ofloxacino/farmacologia , TailândiaRESUMO
The increasing incidence of multidrug-resistant tuberculosis (MDR-TB) and the emergence of extensively drug-resistant tuberculosis (XDR-TB) globally hamper the successful treatment and effective control of TB. Information on second-line drug susceptibility, which is of utmost importance for patient care, is still limited. This study demonstrates the susceptibilities of 1447 strains of MDR-TB, including 58 XDR-TB strains, isolated from Siriraj Hospital, Bangkok, Thailand, to aminoglycosides, fluoroquinolones, ethionamide (ETH), para-aminosalicylic acid (PAS) and linezolid. Results revealed that 93-94% of the MDR-TB strains were susceptible to aminoglycosides, 85-98% to fluoroquinolones, 78% to ETH, 85% to PAS and 99% to linezolid.
Assuntos
Antituberculosos/farmacologia , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Acetamidas/farmacologia , Aminoglicosídeos/farmacologia , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Fluoroquinolonas/farmacologia , Humanos , Linezolida , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/isolamento & purificação , Oxazolidinonas/farmacologia , Tailândia/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologiaRESUMO
BACKGROUND: The aim of this study was to assess the use of qualitative one-tube nested polymerase chain reaction (PCR) for monitoring the treatment response in smear-positive pulmonary tuberculosis, and the factors determining the negative conversion of sputum smear, culture, and PCR during treatment. METHODOLOGY: A total of 53 patients receiving a standard short course of chemotherapy with 24 months follow-up period after treatment cessation were included in the study. Sputum specimens were collected serially for smear, culture, and PCR until the treatment was complete. RESULTS: The conversion rate for sputum culture, smear, and PCR at 8 weeks after treatment were 84.9, 58.5, and 47.1%, and at 16 weeks of treatment were 100, 88.7, and 79.2%, respectively. At the end of the treatment period, there were four PCR persisters, one of whom had disease relapse. Only cavitary disease had an influence over the negative conversion of the smear and PCR at 8 weeks (RR 3.5, 95% CI 1.04-11.95, P=0.04 for smear; RR 5.06, 95% CI 1.196-21.42, P=0.03 for PCR). CONCLUSION: Qualitative PCR was not useful for monitoring therapy in smear-positive pulmonary tuberculosis. Mycobacterium DNA was cleared slowly in cavitary disease. The PCR may be performed at the time of treatment cessation to identify those with potential for disease relapse.