Spoligotype Diversity and Drug Resistance of Archived Mycobacterium Tuberculosis Complex Isolated from Patients Presenting at the Greater Accra Regional Hospital

Abstract

Tuberculosis remains an important cause of infection in Ghana and Africa despite efforts put in place to eradicate it. Investigations to understand the population dynamics and circulating strains of the Mycobacterium tuberculosis complex will provide effective strategies in the control of the disease. This study was aimed at investigating and establishing the spoligotype diversity and drug-resistance profile of archived Mycobacterium tuberculosis complex isolates. A total of ninety (90) archived MTB isolates were analysed using the Capilia TB-Neo Immunochromatographic test and spoligotype to determine strain lineages. The samples were also subjected to the HAIN Genotype MTBDRplus assay to ascertain their drug resistance profiles. Spoligotyping results were used to query the International Spoligotyping database SITVIT2. The isolates generated 40 distinct spoligotype patterns with 5 major clusters. Identified families were Cameroon, T1, T3, AFRI_2, H3, LAM 9, AFRI_1, CAS, T4, AFRI, EAI 5, and Family 33. The dominant lineages were the Cameroon lineage with SIT 61 (31.11%), T1 family SIT 53 (11.11%), T3 family SIT 504 (6.67%), and Mycobacterium africanum (West African type 2, SIT 331) (3.33%). MIRU-VNTRplus database returned a cluster rate of 56.66% with Cameroon SIT 61 having the largest cluster. The HAIN Genotype MTBDRplus assay detected 20.45% (18/88) resistant isolates with 5.68% (5/88) being MDR. Significant mutations were seen in codon 526, 516, and 531 of the rpoB gene and on codon 315 of the katG gene for isoniazid and in inhA -15C/T of the promoter region.