Title: Sputum Smear Conversion Time of HIV Infected and Uninfected Patients with Rifampicin and Isoniazid Mycobacterium tuberculosis gene Mutations in Western Kenya
Authors: Shiluli, Clement, Ouma, Collins, Vulule, John, Khayumbi, Jeremiah, Murithi, Wilfred, Musau, Susan, Okumu, Albert
DOI: https://dx.doi.org/10.18535/jmscr/v4i12.28
Background: In 2013, an estimated 9.0 million people developed tuberculosis (TB) and 1.5 million died from the disease, 360 000 of whom were HIV-positive. A major challenge to TB management is the multi-drug resistant (MDR) TB strains and HIV. There are few studies in western Kenya on the specific mutations underlying resistance to rifampicin (RIF) and isoniazid (INH) and the time to sputum smear conversion, especially in HIV-infected patients. Methods: We therefore studied sputum smear conversion time in TB and HIV co-infected patients with previously confirmed rpoB, katG and inhA Mycobacterium tuberculosis gene mutations. Drug sensitivity tests and line probe assays had been performed previously on sputum samples from participating patients. Samples with discordant results were further sequenced to confirm rpoB, katG, and inhA gene mutations that have been associated with RIF and INH mutations. Gene mutations were classified into three categories based on specific codons with mutations on the rpo B, kat G, and in hA genes as follows, MDR-TB, RIF mono-resistant (RMR) TB and isoniazid mono-resistant (INHMR) TB. Ziehl-Neelsen (ZN) microscopy was done on sputum samples from enrolled patients on two occasions; during first and follow-up visits at respective health facilities. The period of follow-up was less than one year. Smear results were available for 16 patients with confirmed drug resistant TB. The smear conversion rate was determined by dividing the number of patients who had a negative smear during follow-up and the number of smear positive patients on first visit and multiplying by 100.Spearman’s correlation coefficient was used to assess the strength of associations between continuous and ordinal variables. Results: The smear conversion rate for participating patients was as follows; RMR-TB = 100%, INHMR-TB = 60% and MDR-TB = 67%.All the patients had positive Mycobacterium tuberculosis cultures. There was positive correlation between follow-up days and ZN smear results, (rs(14) = 0.097, p = 0.721). Conclusion: Sputum smear conversion time can be used in monitoring drug resistant TB in both HIV-infected and -uninfected patients. Keywords: Tuberculosis, HIV, MDR-TB, isoniazid mono resistant, rifampicin mono resistant gene sequencing.
Shiluli, Clement School of Public Health and Community Development, Department of Biomedical Sciences and Technology, Maseno University, P.O. Private Bag, Maseno Email: This email address is being protected from spambots. You need JavaScript enabled to view it., Mobile Number+254 723 474 168Abstract
