Evaluation of a novel, two component, two step AFB cold staining method.

AFB smear is a clinically useful and a cost effective test for screening of sputum samples for Mycobacterium tuberculosis. Routinely, Ziehl Neelsen stain, using the traditional hot staining procedure is the mainstay of sputum smear AFB tests. We have evaluated a novel two components, two step cold AFB stain to establish its sensitivity, simplicity and reproducibility as compared to the traditional 'ZN Hot' stain still regarded as the standard AFB stain in routine laboratory practice. This study was conducted over a period of four months at the TB Hospital, Taleigao Goa. Comparatively the two components, two step AFB stain was easy to use, time, labour and cost saving. It gave reproducible results during the study period. The most important characteristics were that it nearly doubled (approximately 91%) the detection rate of AFB positive sputum in our hospital.