OBJECTIVE: To determine primary and acquired resistance to pyrazinamide in Mycobacterium tuberculosis strains isolated in sputum samples from patients with pulmonary tuberculosis. METHODS: This was a prospective, descriptive study conducted between April and November of 2011 at a referral hospital for tuberculosis in the city of Recife, Brazil. Cultures, drug sensitivity tests, and tests of pyrazinamidase activity were conducted in a private laboratory in Recife. RESULTS: Of the 71 patients included in the study, 37 were treatment-naïve and 34 represented cases of retreatment. Pyrazinamide-resistant strains were isolated in 14 (41.2%) of the 34 patients who had previously been treated for tuberculosis and in none of the 37 treatment-naïve patients. Of the 14 isolates, 10 (90.9%) tested negative for pyrazinamidase activity. A total of 60 isolates tested positive for pyrazinamidase activity. Of those, 56 (93.3%) were found to be sensitive to pyrazinamide. CONCLUSIONS: The high frequency of pyrazinamide-resistant strains (41.2%) in patients previously treated for tuberculosis highlights the need for drug susceptibility testing prior to the adoption of a new treatment regimen.
OBJECTIVE: To determine primary and acquired resistance to pyrazinamide in Mycobacterium tuberculosis strains isolated in sputum samples from patients with pulmonary tuberculosis. METHODS: This was a prospective, descriptive study conducted between April and November of 2011 at a referral hospital for tuberculosis in the city of Recife, Brazil. Cultures, drug sensitivity tests, and tests of pyrazinamidase activity were conducted in a private laboratory in Recife. RESULTS: Of the 71 patients included in the study, 37 were treatment-naïve and 34 represented cases of retreatment. Pyrazinamide-resistant strains were isolated in 14 (41.2%) of the 34 patients who had previously been treated for tuberculosis and in none of the 37 treatment-naïve patients. Of the 14 isolates, 10 (90.9%) tested negative for pyrazinamidase activity. A total of 60 isolates tested positive for pyrazinamidase activity. Of those, 56 (93.3%) were found to be sensitive to pyrazinamide. CONCLUSIONS: The high frequency of pyrazinamide-resistant strains (41.2%) in patients previously treated for tuberculosis highlights the need for drug susceptibility testing prior to the adoption of a new treatment regimen.
Authors: Ronise Malaquias Carlos Valadares; Wânia da Silva Carvalho; Silvana Spíndola de Miranda Journal: Rev Soc Bras Med Trop Date: 2019-12-20 Impact factor: 1.581
Authors: M J Nasiri; F Fardsanei; M Arshadi; B Deihim; Farima Khalili; M Dadashi; M Goudarzi; M Mirsaeidi Journal: New Microbes New Infect Date: 2021-05-05
Authors: Michael G Whitfield; Heidi M Soeters; Robin M Warren; Talita York; Samantha L Sampson; Elizabeth M Streicher; Paul D van Helden; Annelies van Rie Journal: PLoS One Date: 2015-07-28 Impact factor: 3.240