Culture and sensitivity of mycobacterial isolates from cases of pulmonary tuberculosis classified as treatment failures in a teaching hospital

Background: The level of drug resistance in mycobacterial isolates from previously treated cases in Ghana is not known although drug resistant tuberculosis threatens efforts to control the disease. Objective: To identify and determine the susceptibility of mycobacterial isolates from tuberculosis cases with clinical treatment failure. Methods: This prospective survey was undertaken at the Chest Clinic of Korle Bu Teaching Hospital in Accra, Ghana. The participants were twenty-eight cases referred to the hospital with clinical treatment failure. Two sputum specimens from each case were stained by Ziehl-Neelsen method, cultured, identified and sensitivity tests performed by the proportion method. Results: Eighteen isolates of mycobacteria were identified from 28 failed treatment cases. Five were atypical mycobacteria. Approximately fifty percent (13/28) of cases had Mycobacterium tuberculosis, 5(18%) had atypical mycobacteria, 7(25%) had pure fungal growth and 3(11% 8) had no growth. Fifteen isolates were resistant to two or more drugs, of which 6 were resistant to all four drugs tested. Conclusion: Continuous drug resistance monitoring must be instituted as part of the tuberculosis control programme.