Non-cultivable mycobacteria in ulcers of the skin.

In biopsies of 54 patients suffering from chronic dermatological lesions (mostly ulcers of the skin) acid-fast bacilli were found in 14. In these 14 cases in 4 were lesions caused by M. tuberculosis, in 1 the lesion was caused by M. avium-intracellulare, in 1 the lesion was caused by M. fortuitum and in 2 the lesions were caused by non-cultivable mycobacteria (Feldmann-Hershfield ulcer?). In 2 cases the cultures were heavily contaminated, and the diagnosis remained uncertain. In the remaining 4 cases the mycobacteria were considered occasional isolates without clinical significance.