Low anti tuberculosis drug resistance despite high rates of recurrent tuberculosis and HIV infection in western Kenya

Abstract

Background: The high rates of recurrent tuberculosis and HIV in Kenya raised the assumption that anti -tuberculosis drug resistance may be an increasing problem.

Objective: To determine whether HIV co infection and TB recurrence are associated with anti TB drug resistance.

Methods: Cross sectional study in which sputa from 872 TB suspects underwent ZN smear microscopy and culture. Growth was identified using Hain molecular identification kits. Screening for HIV infection was done using Uni GoldTM rapid test and the positives confirmed with enzyme linked immunosorbent assay.

Results: A total of 186 M. tuberculosis complex and 15 non tuberculous mycobacteria isolates were obtained. The tuberculosis recurrence and TB HIV co infection rates amounted to 44.8% and 41.8%, respectively. All the 186 M. tuberculosis isolates were susceptible to streptomycin and ethambutol. Only 12 (6.5%) of the isolates were mono drug resistant, nine to isoniazid and three to rifampicin. Only 3/27 isoniazid resistant isolates were from recurrent TB cases.

Conclusion and recommendation: No MDR strains of M. tuberculosis were observed in the current study. However, the study suggests an association between HIV co-infection and anti TB mono drug resistance. High TB recurrence observed in the current study was not associated with anti TB drug resistance. What needs to be examined is the cause of this high TB recurrence rate in Western Kenya.

Keywords: Recurrent TB; HIV co infection; antiTB drug resistance; prevalence