Detection of mycobacteria in sputum smears prepared by cytocentrifugation and sedimentation.

The efficacy of sedimentation combined with cytocentrifugation of sputa was examined by preparing smears for the detection of mycobacteria. The detection of acid-fast bacilli from sputum sediment by cytocentrifugation yielded 32 smears positive for acid-fast bacilli, out of which in 26 cases better results were obtained than by the conventional method. More bacilli were found in 20 cases and on 6 occasions solely the cytospin method was positive. The differences in the number of bacilli were 100-200-fold in 5 cases and 10-fold in 12 paired cases. The technique applied is suitable for making culture and smear from the same sediment. The sedimentation combined with cytocentrifugation increases the effectiveness of the detection of acid-fast bacilli in smears.