Related Experiment Video
Updated: Oct 1, 2026
Methodology for Sputum Induction and Laboratory Processing
Published on: December 17, 2017
Washing of new microscopic glass slides in dichromate solution does not influence sputum AFB smear results
N Selvakumar1, E Prabhakaran, F Rehman
1Tuberculosis Research Centre (ICMR), Chennai, India. modeldots@vsnl.com
Setting:
Microscopy centres in Tiruvallur District, Tamil Nadu, India, implementing DOTS.
Objective:
To know whether washing new glass slides in dichromate solution is essential for effective sputum acid-fast bacilli microscopy.
Methods:
Two direct smears were prepared from each of 1750 sputum samples. One was made on dichromate solution-cleaned new glass slides and the other was made on unwashed new glass slides. The smears were blinded and examined.
Results:
Of the 1750 specimens, 13.5% and 13.08% were positive for AFB using washed and unwashed slides, respectively (P = 0.12). The concordance between these two (including one grade above and one below) was 98.7%.
Conclusion:
Washing of new glass slides in dichromate solution is not essential for AFB microscopy.
