Objective: To determine the prevalence and patterns of primary and acquired drug resistance among Mycobacterium tuberculosis isolates recovered from tuberculosis patients in Poland.
Design: In a prospective survey, M. tuberculosis strains were collected from 3970 tuberculosis patients (2976 newly diagnosed cases and 994 previously treated patients) bacteriologically confirmed by culture between November 1996 and October 1997.
Methods: Drug susceptibility testing to isoniazid (INH), streptomycin, ethambutol and rifampicin (RMP) was performed on Löwenstein-Jensen medium according to the proportion method and/or using the radiometric Bactec 460 TB system.
Results and conclusion: The male to female ratio was 2.61:1. The patients were aged between 6 and 82 years, with 86% of males and 77% of females aged over 35 years. Primary resistance to any drug was found in 3.6% of new patients; any INH resistance was 2.6%, any RMP resistance was 0.7%, and multidrug resistance (to INH and RMP [MDR]) was 0.6%. In previously treated cases, resistance to any drug was 17.0%, any INH resistance 14.1%, any RMP resistance 7.8%, and MDR 7.0%. Drug-resistant tuberculosis does not present a big problem in Poland; primary drug resistance has been monitored since 1960 with decreasing frequency, and rates remain at the same level as 20 years ago. Studies such as this should be conducted regularly to monitor drug resistance in Poland in order to effectively manage national tuberculosis control efforts.