Demonstration of Mycobacterium Tuberculosis in Sputum and Saliva Smears of Tuberculosis Patients Using Ziehl Neelsen and Flurochrome Staining- A Comparative Study

Background: Early detection of tuberculosis is important for reducing its morbidity and mortality especially in the patients with non-productive cough. To overcome the cumbersome process involved in collection and processing of the sputum specimen, the time consumed for reporting of sputum by Ziehl Neelsen (ZN) method and to introduce a routine screening test in suspected, symptomless tuberculosis patients, the present study was designed using saliva as diagnostic medium and Auramine Rhodamine (AR) as staining method. On review of literature, there was no study which has tried diagnosing tuberculosis using saliva with flurochrome stain; hence the present study was designed. Aim: To introduce a routine screening test for tuberculosis patient using saliva and to determine the diagnostic efficacy of routine ZN staining method and AR fluorescent staining method in sputum and saliva smears of pulmonary tuberculosis patients. Settings and Design: Laboratory settings and Experimental design. Materials and Method: Fifty smears samples of sputum and saliva of known cases of pulmonary tuberculosis were stained with routine ZN stain and other with AR fluorescent stain. All the specimens were inoculated into Lowenstein-Jensen culture media. The smears were subjected for scanning of Mycobacterium tuberculous bacilli under X 1000 magnification for ZN stain and X 400 magnification for AR stain by grid pattern proposed by National tuberculosis institute and graded by RNTCP grading system. Results: All 50 sputum samples showed 100% positivity by ZN and AR stain while only 76% positivity was seen by culture. Of the 50 saliva samples 10% cases were positive by ZN, 76% were positive by AR & 70% by culture method. Statistical analysis using chi square test was done, and the value was found to be statistically highly significant for AR staining technique. (p<0.001) Conclusion: Saliva can prove to be an important tool for the diagnosis as well as screening of the patients with pulmonary tuberculosis when aided with flurochrome staining method.