Open Access Highly Accessed Research article

Drug resistance-conferring mutations in Mycobacterium tuberculosis from Madang, Papua New Guinea

Marie Ballif12, Paul Harino3, Serej Ley123, Mireia Coscolla12, Stefan Niemann4, Robyn Carter5, Christopher Coulter5, Sonia Borrell12, Peter Siba3, Suparat Phuanukoonnon3, Sebastien Gagneux12 and Hans-Peter Beck12*

Author Affiliations

1 Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland

2 University of Basel, Basel, Switzerland

3 Papua New Guinea Institute of Medical Research, Goroka and Madang, Papua New Guinea

4 Borstel Research Center, Borstel, Germany

5 Queensland Mycobacterium Reference Laboratory, Pathology Queensland, Brisbane, Australia

For all author emails, please log on.

BMC Microbiology 2012, 12:191  doi:10.1186/1471-2180-12-191

Published: 4 September 2012

Abstract

Background

Monitoring drug resistance in Mycobacterium tuberculosis is essential to curb the spread of tuberculosis (TB). Unfortunately, drug susceptibility testing is currently not available in Papua New Guinea (PNG) and that impairs TB control in this country. We report for the first time M. tuberculosis mutations associated with resistance to first and second-line anti-TB drugs in Madang, PNG. A molecular cluster analysis was performed to identify M. tuberculosis transmission in that region.

Results

Phenotypic drug susceptibility tests showed 15.7% resistance to at least one drug and 5.2% multidrug resistant (MDR) TB. Rifampicin resistant strains had the rpoB mutations D516F, D516Y or S531L; Isoniazid resistant strains had the mutations katG S315T or inhA promoter C15T; Streptomycin resistant strains had the mutations rpsL K43R, K88Q, K88R), rrs A514C or gidB V77G. The molecular cluster analysis indicated evidence for transmission of resistant strain.

Conclusions

We observed a substantial rate of MDR-TB in the Madang area of PNG associated with mutations in specific genes. A close monitoring of drug resistance is therefore urgently required, particularly in the presence of drug-resistant M. tuberculosis transmission. In the absence of phenotypic drug susceptibility testing in PNG, molecular assays for drug resistance monitoring would be of advantage.

Keywords:
Mycobacterium tuberculosis; Papua New Guinea; Drug resistance; Mutations