Drug Susceptibility of Brazilian Strains of Mycobacterium bovis Using Traditional and Molecular Techniques

• Published in: Memórias do Instituto Oswaldo Cruz Vol. 99; no. 7; pp. 749 - 752
• Main Authors: Parreiras, Patrícia M, Lobato, Francisco C F, Alencar, Andréa P, Figueiredo, Telma de, Gomes, Harrison M, Boéchat, Neio, Lage, Andrey P, Assis, Ronnie A, Pereira, Márcia A S, Souza, Patrícia R, Mota, Pedro M P C, Suffys, Philip N
• Format: Journal Article
• Language: English
• Published: Brazil Fundação Oswaldo Cruz, Fiocruz 01-11-2004; Instituto Oswaldo Cruz, Ministério da Saúde; Fundação Oswaldo Cruz (FIOCRUZ)
• Subjects: Animals; Antitubercular Agents - pharmacology; Cattle; drug susceptibility; Humans; isoniazide; Microbial Sensitivity Tests - methods; Mycobacterium bovis; Mycobacterium bovis - drug effects; Mycobacterium bovis - drug susceptibility - isoniazide - rifoligotyping; Mycobacterium bovis - genetics; Mycobacterium bovis - isolation & purification; PARASITOLOGY; Retrospective Studies; rifoligotyping; TROPICAL MEDICINE; rifoligotyping; isoniazide; Mycobacterium bovis; drug susceptibility
• ISSN: 1678-8060; 0074-0276; 0074-0276; 1678-8060
• DOI: 10.1590/S0074-02762004000700015

Transmission of Mycobacterium bovis from cattle to humans has been
reported and can cause tuberculosis (Tb) and a problem in certain risk
populations. Therefore, knowledge of resistance of M. bovis towards
antibiotics used for therapy of human Tb could help avoiding cure delay
and treatment cost increase when dealing with drug resistant organisms.
We therefore evaluated the susceptibility of M. bovis isolates towards
streptomycin, isoniazide, rifampicin, ethambutol, and ethionamide, the
first line antibiotics for human Tb. Therefore, 185 clinical samples
from cattle with clinical signs of tuberculosis were processed and
submitted to culturing and bacterial isolates to identification and
drug susceptibility testing using the proportion method. Among 89
mycobacterial strains, 65 were identified as M. bovis and none were
resistant to any of the antibiotics used. Confirmation of present
results by future studies, enrolling a large number of isolates and
designed to properly represent Brazilian regions, may favor the idea of
using isoniazide preventive therapy as part of a Tb control strategy in
special situations. Also, nucleic acids from bacterial isolates were
submitted to rifoligotyping, a recently described reverse hybridization
assay for detection of mutations causing resistance towards rifampicin.
Concordance between the conventional and the molecular test was 100%,
demonstrating the use of such methodology for rapid evaluation of drug
susceptibility in M. bovis.