To determine magnitude, trend and specific features of the resistance problem.
Royal Netherlands Tuberculosis Association, The Hague, the Netherlands.
The data of the National Institute of Public Health and Environmental Protection concerning the prevalence of drug-resistant tuberculosis during the period 1990-1994 were analysed. Also, features of patients with and without drug resistance were compared (Dutch National Tuberculosis Register: cohort 1993).
Isoniazid and streptomycin resistance were each observed in approximately 6 of susceptibility tests, showing no clear trend over the study period. Rifampicin resistance increased from 0 to 1.5 in 1994. In the 1993 patient cohort, 809 cases were analysed, showing resistant organisms in 103 (13). The resistance group included 84 (82) foreigners versus 387 (55) among the ‘sensitives’ (p < 0.001). The percentages of (known) HIV infections were equal in both groups (5-6). The percentage of isoniazid-resistance varied from 1.8 in Dutch patients to 7.8 in foreign patients. Recent immigrants and refugees waiting for official status were important risk groups for resistance (p < 0.005). Foreign tuberculosis patients defaulted more often from treatment than Dutch patients (p < 0.001).
Drug-resistant tuberculosis in the Netherlands is mainly due to import of resistant strains. Transmission and further development of resistance within the country must be prevented.