Review on advanced diagnostic techniques for Mycobacterium species and its significance to control Tuberculosis

Abstract

Mycobacteria species are a group of bacteria that are responsible for tuberculosis infection which affects mainly lung, lymph glands, skin, bone disease in humans and animals worldwide. Tuberculosis (TB) is an infectious and transmissible disease mainly caused by Mycobacterium tuberculosis complex and it is one of the major public health problems worldwide that affects all age groups. Ethiopia ranks ninth among 22 high tuberculosis burden countries in world and one of the top 3 in Africa. The disease is affecting large segments of the populations in the country. It is caused by the genus of Mycobacterium which includes many pathogens known to cause serious disease in mammals. Species in Mycobacterium tuberculosis complex group are characterized by 99.95 % or greater similarity at nucleotide level and posses identical 16 SrRNA sequences but differ widely in terms of their host tropisms, phenotypes and pathogenecity. The diagnosis of Mycobacterium species can be made by direct and indirect methods including clinical examination, gross and histopathological examination, Mycobacteriological culture isolation methods and biochemical tests. These methods can be grouped as conventional mycobacterial dignosictic techniques. Other tests include immunological techniques (tuberculin skin test, interferon gamma release assays, lymphocyte proliferation assay). Furthermore, there are advanced diagnostic molecular techniques includes DNA probes, gene amplification methods, PCR, Multiplex PCR, RT-PCR, restriction fragment length polymorphism, Spoligo typing, MIRU-VNTR assay, and whole Genome sequencing. The combination of conventional, immunological and molecular techniques is the best option to develop appropriate control and prevention measures against tuberculosis in both human and animals.