Comportamiento de indicadores de calidad del cultivo en los laboratorios de diagnóstico de tuberculosis en la provincia de Las Tunas, Cuba

background: the bacteriological culture, it is the golden test for the definitive diagnosis of the tuberculosis (tb). the purpose of the quality control is improve the efficiency and use of culture like an alternative of diagnosis and monitoring, and assuring that the information generated by the laboratory are reliable and exact. method: the quality indicators (qi) were calculated in 5799 sputum samples, from patients with pulmonary tb confirmed by bacteriological culture, received in the tb diagnosis laboratories from las tunas province, 4721 from tb laboratory of the hygiene and epidemiology provincial center (hepc) and 1078 from tb laboratory of the hygiene and epidemiology municipal center (hemc) of the puerto padre municipality, from october 2003 to september 2005. results: in the hepc the contamination rate (cr), the culture contribution to the diagnosis (ccd) and the percent of positive baciloscopy with negative culture (% bk+ cu -) was 4.3%, 34.8% and 6.3% respectively. in the laboratory of the hemc the cr was 7.6% and the rest of the indicators were 0%. conclusions and recommendations: the qi of culture in the hepc laboratory from las tunas municipality, excepting the % bk (+) cu (-) presented acceptable values for a good performance, in the hemc laboratory from puerto padre municipality, the ic values, to exception of the % bk (+) cu (-), were superiors to the established for the international norms. we recommended incorporate the calculation of qi in the national network of laboratories culture, in order to improve the yield and quality of tb diagnosis.