Detecção rápida de resistência aos fármacos de segunda linha (fluroquinolonas, amicacina e canamicina) em cepas de Mycobacterium tuberculosis utilizando o método Multiplex allele-specific PCR (MAS-PCR)

• Ano de defesa: 2016
• Autor(a) principal: Costa, Bianca Porphírio da
• Orientador(a): Siqueira, Hélio Ribeiro de
• Banca de defesa: Amadeu, Thaís Porto , Ferreira, Prescilla Emy Nagao , Montes, Fátima Cristina Onofre Fandinho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade do Estado do Rio de Janeiro
• Programa de Pós-Graduação: Programa de Pós-Graduação em Ciências Médicas
• Departamento: Centro Biomédico::Faculdade de Ciências Médicas
• País: BR
• Palavras-chave em Português: MAS-PCR; M. tuberculosis; MGIT; Amicacina; Canamicina; Ofloxacina; Fluoroquinolonas; Mycobacterium tuberculosis; Tuberculose
• Palavras-chave em Inglês: MAS-PCR.; M. tuberculosis.; MGIT. Amikacin; Kanamycin; Ofloxacin; Fluoroquinolones
• Área do conhecimento CNPq: CNPQ::CIENCIAS DA SAUDE::MEDICINA::CLINICA MEDICA
• Link de acesso: http://www.bdtd.uerj.br/handle/1/8838

Tuberculosis remains one of the main causes of death caused by a single infectious agent worldwide. Deficiencies in the disease detection process as well as failure of some therapeutic procedures (e.g., due to the abandonment of the treatment by the patient) has contributed to the emergence of bacteria resistant to one or more antibiotics (MDR - multidrug resistance and XDR - extensively drug-resistant), constituting a serious problem and a real threat to tuberculosis control programs. This study aims to quickly identify strains of Mycobacterium tuberculosis (MTB) resistant to fluoroquinolones (FLQs), amikacin (AMK) and kanamycin (KAN) by point mutations in gyrA genes (codon 94) and rrs (codon 1045), respectively. The methodology used was the MAS-PCR (Multiplex Allele-Specific - PCR) which is based on PCR amplification and simultaneous detection of point mutations most frequently associated with resistance to FLQs, AMK and KAN in MTB strains. One hundred M. tuberculosis strains belonging to the collection of National Reference Laboratory for Tuberculosis / CRPHF / ENSP / FIOCRUZ were analyzed by MAS-PCR method and compared to the results obtained previously by bacteriological and automated method BACTEC MGIT 960. The results showed disagreement between the MAS-PCR molecular method and phenotypic method MGIT 960 (42% in the gyrA gene and 32% in the rrs gene). The discordant results were analyzed by sequence analysis, showing that the sensitivity of the MAS-PCR method with the gyrA gene was 71.4% and the rrs gene was 52.5%. The low value of sensitivity is due to the fact that some resistant strains showed no mutation at the position analyzed by MAS-PCR, which may mean that the resistant MTB strains present in Brazil have a singularity in the pattern of mutations, other than described in the rest of the world.