Background and purpose: During 1998-2002, most specialized tuberculosis (TB) hospitals in Taiwan were closed; as a result, more TB patients are being managed in general hospital settings. This study investigated the prevalence, patterns and risk factors of drug-resistant Mycobacterium tuberculosis at a university hospital in the 5 years after decentralization of the TB administrative and clinical control infrastructure which occurred during the implementation of the national health insurance system in Taiwan.
Methods: A total of 1411 initial isolates of M. tuberculosis from specimens collected during January 1998 through December 2002 were tested for drug susceptibility of first-line anti-TB drugs using the agar proportional method.
Results: The numbers of newly diagnosed culture-positive TB patients increased from 139 in 1998 to 380 in 2002. The drug resistance pattern of M. tuberculosis among these isolates was as follows: 268 (19.0%) strains were resistant to isoniazid, 86 (6.1%) to rifampin, 221 (15.7%) to ethambutol, 141 (10.0%) to streptomycin, and 430 (30.5%) to 1 of these 4 drugs. Multidrug resistance (MDR), i.e., resistance to at least rifampin and isoniazid, was observed in 72 isolates (5.1%). Of the 1411 patients, isolates from patients with age < 65 years had a higher multiple drug resistance rate than those from patients with age > or = 65 years (57/781, 7.3% vs 15/630, 2.4%; p < 0.001). In the analysis of risk factors for MDR, patients with MDR isolates had a significantly higher incidence of previous TB history, anti-TB therapy, longer duration of symptoms, cavitary lesions in chest X-ray, and mortality.
Conclusion: A dramatic increase in cases of TB among patients treated at this university hospital was seen after the decentralization of the TB control infrastructure in Taiwan. The prevalence of drug resistance in isolates from culture-positive TB patients was 30.5% and the prevalence of MDR was 5.1%.