Prevalence of Injectable Anti-Tuberculosis Drugs and Drug Resistance Amongst TB Patients in The Vhembe District (Limpopo, South Africa

Abstract

Background: Tuberculosis is one of the most infectious diseases and a major contributor to high mortality and morbidity rates worldwide. The rise of human immunodeficiency virus cases also compounds to the tuberculosis burden, as human immunodeficiency virus patients are thought to be more susceptible to tuberculosis, since the disease is an opportunistic infection and makes an individual’s immune system less capable of fighting off infections. Drug resistance tuberculosis makes transmission and combatting of disease challenging, particularly multi-drug resistant strains that are resistant to at least isoniazid and rifampicin, pre-XDR, resistant to isoniazid, rifampicin and a fluoroquinolone and extensively-drug resistant, a rare form of multidrug resistance tuberculosis that is resistant to isoniazid, rifampicin, fluoroquinolone, and a secondline injectable (amikacin, capreomycin, and kanamycin). Resistance to fluoroquinolone and injectable drugs is not frequently tested due to budget constraints and the ongoing high tuberculosis burden in developing nations. Furthermore, there is insufficient knowledge about extensively-drug resistant strains and mutations connected to fluoroquinolone and injectable drugs in South Africa. Thus, the purpose of this study was to determine the frequency of genetic mutations in M. tuberculosis obtained from tuberculosis positive patients attending medical facilities in the Vhembe region of the province of Limpopo, South Africa, with respect to genotype conferring resistance for INH, RIF, EMB, PZA, FQs, all of which are linked to resistance to second-line drugs. Methods: Ethical clearance was obtained, a total of 50 morning sputum samples were collected from health-care facilities. Structured questionaries were also administered to collect additional information. Collected data was analysed to investigate the risk factors associated with drug resistance tuberculosis. Allplex Multiplex polymerase chain reaction permitted simultaneous amplification and detection of target sequence of Mycobacterium tuberculosis. In order to determine genetic mutations, 8 single-nucleotide polymorphisms were targeted using MassARRAY (Agena) system. Results: Among the 50 tuberculosis recruited patients (from the pool of main study August 2022- June 2023), 60% were males and 40% were females. HIV was highly (66%) prevalent amongst study population; susceptible tuberculosis 4%, MTB & NTM 28% (co-infection), NTM 58% and 4% drug resistance were observed. Overall, of the SNPs designed only 8 related gene mutations could be successfully detected. Overall, from the study population, 2 samples were detected to be pre-XDR (FQ-R and RIF-R + INH-R + FQ-R). Conclusion: The findings of the study provide valuable insights into the characteristics and prevalence of tuberculosis, along with associated risk factors and co-morbidities among the study population in Vhembe district. The emergence of drug resistance highlights the necessity for continued pattern monitoring and the application of suitable treatment approaches in order to stop the spread of drug-resistant strains. To draw firm conclusions about drug-resistant tuberculosis risk factors in patients in the Vhembe region, further information is still required.