[Tuberculosis relapse in the GDR--causes and development].

In a cooperative study 169 bacteriologically confirmed tuberculosis relapses of the years 1984-1986 were analysed with regard of causes or relapse favouring factors. In 58.5% relapse occurred 3 or more years after cessation of previous treatment. Relapse was presumedly caused in 22.3% by inadequate chemotherapy (considering duration and/or continuation and/or combination), in 25% by alcoholism and in 14.9% by silicosis. Resistance to 2 or more antituberculotic drugs was found only in 5.3%. Advanced age and polymorbidity are relapse favouring factors. Consideration of adequate chemotherapy is the most important factor to avoid relapse.