Rifamycin is a key component of the World Health Organization Directly Observed Therapy Scheme (, short course) regimen and, since RIF mono-resistance is extremely rare, INH resistance is usually preceded by that of RIF. These drugs include KatG, inhA, aphC, kasA and ndh for INH resistance rpoB for RIF resistance rpsL and rrs for Streptomycin (SM) embB for Ethambutol (EMB) apncA for Pyrazinamid (PZA) resistance. Ten (10) genes are known to be linked to resistance to the first line antituberculosis drugs. The emergence of multi-drug resistant strains of Mycobacterium tuberculosis, with resistance to at least rifampin (RIF) and isoniazid (INH) is due to particular genomic mutations of Mycobacterium tuberculosis. As such the World Health Organization declared TB to be a global public health emergency. TB will undoubtedly increase in prevalence in most countries due to increasing number of multidrug resistant (MDR) Mycobacterium tuberculosis strains and the Human Immunodeficiency Virus (HIV) pandemic. It accounts for about one third of all preventable adult deaths globally. Tuberculosis (TB) remains one of the world’s most serious problems, causing about 3 million deaths per year. Received 16 March 2016 accepted 4 June 2016 published 7 June 2016 The Dot-blot technique will be useful in rapidly assessing the effectiveness of national TB control programs in limiting the spread of resistance strains in Cameroon. Resistance to RIF and SM due to mutations on the rpoB and rrs genes respectively in the SW region was found to be high and comparable to the drug susceptibility testing by 92%, (95% CI: 75.7 - 99.1). Double mutation on rpoB and rrs genes occurred in 8 (13.6%) DNA samples. Phenotypic resistance and genotypic susceptibility were found in 5 (8.5%) RIF and 3 (4.7%) SM compared to phenotypic susceptibility and genotypic resistance that were found in 2 (3.5%) RIF and 3(4.7%) SM. 12 (20.3%) samples showed phenotypic and genotypic resistance to RIF compared to 34 samples (58.1%) for SM. Mutational analysis demonstrated that resistance to RIF was common in females (52.1%) than males (41.7%) while 6% of the samples were indeterminate. Amplification for the gene showed that there was (59) 100% amplification with primers used for rpoB genes and 43 (72.9%) amplification with primers used for the rrs gene. Of the 59 sputum samples collected (36 were males and 23 were females) came from Buea 19 (32.2%), Limbe 20 (33.9%) and Tiko 20 (33.9%) towns respectively. Cultures from 59 patients were tested for rifampicin and streptomycin sensitivity by the modified proportion method and mutational analysis for rpoB codon 516 and rrs codon 513 was performed by the dot-blot hybridization technique. Tuberculosis (TB) patients aged 15 to 50 (mean age: 30.50 ± 8.33 standard deviation) were recruited for the study between December 2006 and April 2007. A hospital-based study was conducted at the Regional hospitals of Buea and Limbe and Tiko Central Clinic. The objective of this study was to use the dot-blot hybridization technique in the detection of resistance to rifamycin (RIF) and streptomycin (SM) in South- Western Cameroon and to compare the technique with the routine culture and drug susceptibility testing for detecting resistance in a resource poor country, Cameroon. Public health physicians have difficulties with such an approach due to long wait periods and cannot use it to establish community wide prevalence as a way to understand where resistance may be emerging faster and to limit its spread. Drug sensitivity testing to establish resistance to TB drugs takes many months to arrive at.
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