The laboratory as a tool to qualify tuberculosis diagnosis.

OBJECTIVES To evaluate the performance of laboratory diagnosis of tuberculosis, clinical samples underwent culture, species identification and drug susceptibility testing (DST). METHODS A total of 554 samples from 269 patients were tested for smear microscopy using Kinyoun stain. Culture was performed in Ogawa-Kudoh medium and species identification was performed using the IS6110 amplified region. DST for rifampicin, isoniazid (INH) and streptomycin were carried out using the Resazurin assay. RESULTS Cultures augmented the number of cases diagnosed by 22.1%, IS6110 amplification identified all Mycobacterium tuberculosis strains thus isolated and DST detected three strains resistant to INH and one multidrug-resistant strain. CONCLUSION Simultaneous use of different techniques enhanced culture yield, species identification and detection of drug resistance even in a laboratory with limited facilities.