The incidence of viable tubercle bacilli in tuberculous lesions following chemotherapy: Comparison of two culture techniques

Abstract

Summary Two culture techniques were compared using 286 lesions obtained from 108 patients. Lesions were divided into two equal portions; one portion was homogenized in saline, cultured on solid ATS medium and incubated for a maximum of three months; the second portion was homogenized in Dubos liquid medium containing 0·5 per cent bovine albumin, cultured in Dubos liquid medium and incubated for a maximum of nine months. The results suggest that the differences are not significant for the 286 lesions as a whole, nor the results obtained separately from the 30 ‘target-point’ and 229 ‘open-negative’ lesions. The differences for the 27 ‘closed-negative’ lesions and those lesions with negative smears or low Gaffky counts on smear, favour the albumin method slightly, but this difference falls considerably short of statistical significance at the 5% level.