Anti-tuberculosis drug resistance in two clinics in Ecuador

Two private hospitals, one in the capital city and one in the eastern rainforest of Ecuador.

To document the prevalence of anti-tuberculosis drug resistance in Ecuador in patients who had not received prior treatment and in those who had.

Drug resistance was determined using the proportion method with solid medium on the first isolate of Mycobacterium tuberculosis from all patients who attended the two hospitals between 1989 and 1996. Documentation of prior treatment was obtained by patient interview.

Resistance was identified in 39 of 161 patients (24%) who had had no prior treatment. Resistance was 14.2% to isoniazid, 11.8% to rifampin and 8.7% to both (multidrug-resistant tuberculosis). Among 60 patients who had received prior treatment, 18 (30%) were resistant to isoniazid, and 14 (23.3%) to rifampin, while multidrug resistance was seen in 10 (16.7%).

In these populations the prevalence of resistance both in patients with no prior treatment and in patients with prior treatment was ominously high. The initial treatment regimens and patient management in Ecuador should be re-evaluated in an effort to prevent further increases in drug resistance.