Abstract:
Kenya is classified thirteenth of 27 high TB burden countries. There is need to frequently monitor resistance
patterns of Mycobacterium tuberculosis to prevent increase of multidrug resistant (MDR) cases. To determine
resistance patterns of Mycobacterium tuberculosis in order to detect MDR cases. Patients with pulmonary
tuberculosis were recruited from TB clinics in and around Nairobi. All laboratory work was carried out at Aga Khan
University Hospital Nairobi, Kenya. A total of 286 drug susceptibility tests were carried out on clinical isolates of
Mycobacterium tuberculosis using first line anti-TB drugs. Eighty six (29.9%) isolates were resistant to at least one
of five drugs tested while 200 (70 %) were sensitive. Mono resistance was identified in four of five drugs tested.
Isoniazid had 30.2% resistance, streptomycin 11.6%, ethambutol 13.9% and pyrazinamide 30.2%. Double
resistance was 4.6% for isoniazid and pyrazinamide, 4.6% for streptomycin and isoniazid, 1.2% for rifampin and
streptomycin. Two isolates (1.1%) were MDR- TB, and one was triple resistant with an additional resistance to
ethambutol. Isoniazid is a first line drug used throughout treatment. The high rate of resistance observed could
result to increase in MDR TB cases, unless systematic nationwide surveillance is ongoing.