Prevalence and risk factors of multidrug-resistant tuberculosis in Cubal, Angola: a prospective cohort study

Abstract

Background: Although the Republic of Angola is one of the 14 countries figuring in the three high tuberculosis (TB) burden country lists, the true multidrug-resistant TB (MDR-TB) situation is unknown.

Material and methods: Patients aged 16 years with a diagnosis of pulmonary TB were prospectively enrolled from June 2014 to July 2015. Sputum samples were collected for culture and drug susceptibility testing in all patients, and for Xpert^® MTB/RIF testing in all previously treated patients and in new patients whose sputum remained smear-positive after 2 months of treatment.

Results: A total of 422 patients were included; Mycobacterium tuberculosis was isolated in 308 sputum samples. The prevalence of MDR-TB was 8.0% (18/225) in new patients and 71.1% (59/83) in previously treated patients. Male sex (OR 2.95, 95%CI 1.35-6.44, P = 0.007), previous anti-tuberculosis treatment (OR 20.86, 95%CI 9.53-45.67, P < 0.001), presence of pleural thickening (OR 7.68, 95%CI 1.57-37.43, P = 0.012) and duration of illness >4 months (OR 3.34, 95%CI 1.45-7.69, P = 0.005) were independent risk factors for MDR-TB.

Conclusions: The prevalence of MDR-TB in Cubal, Angola, was higher than estimated by the World Health Organization for Angola and one of the highest worldwide. Facilities to diagnose and treat MDR-TB are urgently needed in Angola.