Evaluation of a Cold Staining Method for Detecting Acid Fast Bacilli in the Sputum

Tuberculosis is a disease of great importance in developing countries, such as India, where it has caused considerable morbidity and mortality. Sputum smear microscopy is the cornerstone in diagnosis of pulmonary tuberculosis, which is usually done using Ziehl–Neelsen (ZN) method (Vasanthakumari et al., 1986; Gupta et al., 2009; Chandrasekaran et al., 1991). The use of ZN Method in remote areas of our country, however, suffers from operational limitations due to shortage of properly trained and experienced laboratory technicians in peripheral centres, and non availability, or short supply of spirit, essential for heating carbol fuchsin. Here we evaluate Cold Staining (CS) as an alternative test to ZN. CS is one modification of ZN which requires carbol fuchsine as a primary stain and Gabbet’s methylene blue, both as a decolorizer and counter stain. Compared to ZN; CS is simple and easy to learn and practice, it is economical and less cumbersome, is suitable under field conditions, and can be practiced even in remote areas and at periphery where laboratory facilities are limited. There are also more practical advantages of CS like, no need of heating in the staining procedure and eliminated the need for separate decolorizing step (requires only two International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 5 Number 6 (2016) pp. 125-129 Journal homepage: http://www.ijcmas.com