Genotyping and Drug Susceptibility Testing of Mycobacterial Isolates from Population-based Tuberculosis Prevalence Survey in Ghana

Background: Tuberculosis (TB) can be caused by two groups of bacteria (mycobacteria) referred to as Mycobacterium tuberculosis complex (MTBC) and non-tuberculosis mycobacteria (NTM). The drugs required to treat TB disease caused by mycobacteria belonging to the two groups may be different. Methods: This study used a new method (Line probe assay) approved by WHO to identify the types of mycobacteria causing TB among people identified to have TB through a national TB prevalence survey in Ghana. The study also determined drugs which could be effective against the types of mycobacteria identified. Results: Out of 361 mycobacteria identified, 165 (45.7%) were MTBC, 120 (33.2 %) were NTM (made up of 14 different specie) and 76 (21.1%) could not be completely identified. Additionally,18(10.9%) and  2(1.2%) out of the 165 of the MTBC were found to be untreatable with Isoniazid and rifampicin (two of the most important ant-TB drugs) respectively. Majority 42/120 (35%) of NTM were of the type referred to as M. fortuitum . Most of the NTM could be treated with macrolides (clarithromycin, azithromycin) and aminoglycosides (kanamycin, amikacin, and gentamicin). Conclusion: Our research signifies an important contribution to TB control in terms of knowledge of the types of mycobacterium species circulating in Ghana and the appropriate drugs for treatment.