Mycobacterium tuberculosis complex drug resistance pattern and identification of species causing tuberculosis in the West and Centre regions of Cameroon
1 Biotechnology Unit, Faculty of Science, University of Buea, P.O. Box 63 Buea, Cameroon
2 Laboratory of Tuberculosis Research, Biotechnology Centre of Nkolbisson, Faculty of Science, University of Yaoundé I, Yaounde, Cameroon
BMC Infectious Diseases 2011, 11:94 doi:10.1186/1471-2334-11-94Published: 15 April 2011
Data on the levels of resistance of Mycobacterium tuberculosis complex (MTBC) strains to first line anti-tuberculosis drugs in Cameroon, and on the species of MTBC circulating in the country are obsolete. The picture about 10 years after the last studies, and 6 years after the re-organisation of the National Tuberculosis (TB) Control Programme (NTBCP) is not known.
The study was conducted from February to July 2009 in the West and Centre regions of Cameroon. A total of 756 suspected patients were studied. MTBC species were detected by the standard Ziehl-Neelsen staining method. Bacterial susceptibility to the first line drugs [isoniazid (INH), rifampicin (RIF), ethambutol (EMB) and streptomycin (SM)] were performed on cultures using the indirect proportion method. MTBC species were identified by standard biochemical and culture methods.
Of the 756 suspected patients, 154 (20.37%) were positive by smear microscopy. Of these, 20.77% were HIV patients. The growth of Mycobacterium was observed with the sputa from 149 (96.75%) subjects. All the isolates were identified as either M. tuberculosis or M. africanum. Among these, 16 (10.73%) were resistant to at least one drug (13.3% for the West region and 8.1% for the Centre). The initial resistance rates were 7.35% for the Centre region and 11.29% for the West region, while the acquired resistance rates were 16.66% (1/6) for the Centre region and 23.07% (3/13) for the West. Within the two regions, the highest total resistance to one drug was obtained with INH and SM (2.68% each). Multidrug-resistance (MDR) was observed only in the West region at a rate of 6.67%. No resistance was recorded for EMB.
M. tuberculosis and M. africanum remain the MTBC species causing pulmonary TB in the West and Centre regions of Cameroon. Following the re-organisation of the NTBCP, resistance to all first line anti-TB drugs has declined significantly (p < 0.05 for West; and p < 0.01 for Centre) in comparison to previous studies. However, the general rates of anti-TB drug resistance remain high in the country, underscoring the need for greater enforcement of control strategies.