[Analize of the determinants of microscopy's quality in the context of tuberculosis fighting within the health centers laboratories in Dakar Region]. / Analyse des déterminants de la qualité de la microscopie pour la lutte contre la tuberculose dans les laboratoires des Centres de Santé de la Region de Dakar.

INTRODUCTION: In order to improve the quality of the microscopy in the context of tracking and following-up the pulmonary tuberculosis patients, a study of the determinants of the quality of microscopy was carried out in the laboratories of the health centres in Dakar Region, Senegal. MATERIALS AND METHODS: We did an epidemiologic study, transversal type which proceeded during April 19th at May 05th, 2004. It consisted of a series of observations, interviews, review of the registers of laboratory and with a second reading and re staining, on the level of the National Laboratory of Reference of the National Programme of fight against Tuberculosis (LNR), of 50 blades collected blindly in the health centres of Dakar. RESULTS: It comes out from this study that there was no statistically significant link between the factors of risk of errors such as the overload of work, the bad condition of the microscope, the lack of competence and the errors observed in certain laboratories. On the other hand the aspect of the smears, the thickness of the smears and the presence of crystals could deteriorate the quality of microscopy because it was found that there was a statistically significant connection between the quality of microscopy and these various determinants. In addition we noted a good agreement of the results of these laboratories with those of the LNR (Kappa test = 0,981, p < 0,0001). CONCLUSION: According to these results, we recommend: a reinforcement of competences (training/recycling) regular of the laboratory assistants, and an installation of a system of quality control of microscopy, interns within the laboratories but also external by the National Laboratory of Reference.