Genitourinary tuberculosis (GUTB) is the second most common form of extrapulmonary tuberculosis, with more than 90% of cases occurring in developing countries. In GUTB, the kidneys are the most common sites of infection and are infected through hematogenous spread of the bacilli, which then spread through the renal and genital tract. Diagnosis of TB is often delayed owing to the nonspecific nature of its presentation; therefore, a high degree of suspicion should be exercised and a systematic approach should be taken during investigation. The aim of this study was to apply bleach concentration method for detection of AFB in 5-day morning urine samples obtained from the suspects of urinary tuberculosis and to correlate the results with conventional Zeihl Neelsen (ZN) staining, TB culture and TB-PCR. A total of 46 samples were studied from clinically suspected cases of urinary tuberculosis. All the samples were processed for conventional ZN staining, Bleach concentration followed by ZN staining, TB culture on LJ media and TB-PCR (IS 6110) by standard protocols. Out of the 46 samples evaluated all were negative (0%) by conventional ZN staining, while the positivity increased to 7(15.22%) by bleach concentration method, the gold standard i.e. TB culture had 9(19.56%) positive and the TB-PCR gave 4(8.69%) positive. The results revealed that bleach concentration method was superior to conventional ZN staining method and TB-PCR. Though TB culture was found to be the best method, but it takes a long time for the diagnosis.

Around 85% of the cases of Tuberculosis (TB) are pulmonary in origin and the routine diagnosis usually depends on sputum microscopy. The conventional direct Ziehl-Nelson (ZN) staining technique has been found to have a low sensitivity. The main objective of the study was to verify whether the bleach concentration method increases the sensitivity of sputum smear microscopy for AFB or not and also to see whether the first single morning sample alone is sufficient and better than the three pooled samples after bleach concentration followed by ZN staining. A total of 365 samples were studied from 131 clinically suspected cases of pulmonary TB which included sputum (112), gastric aspirate (5), endotracheal tube washing (2), and bronchial lavage (12). All these samples were processed for conventional ZN staining and Bleach concentration method followed by ZN staining. An increase in positivity was observed in all the cases after using the bleach concentration method and the most significantly useful was that in the case of first morning sputum samples where it increased from 11.6% to 41.96%. Bleach concentration is a simple, cheap and easily available method and also very safe because it kills the Mycobacteria in the process. Its positivity rate is better as compared to direct conventional ZN staining.