benin population diversity of tuberculosis and implications

Conditions: Tuberculosis

Summary: tuberculosis is a public health problem caused by a microbe. this microbe may differ from one patient to another. the purpose of this study is to know to which extent, each of these various microbes is involved in tuberculosis disease in benin. this study will also find out whether the type that affects a patient, depends on patient characteristics and whether the difference affects the outcome of the treatment. finally the study will also help to find out whether diagnostic tests are reliable for all types of the microbe. this information will be used after the study to inform decision making in order to improve tuberculosis control.

the overall aim of this study is to determine the population structure of mycobacterium tuberculosis complex in benin, and implications for tuberculosis presentation, diagnosis and outcome the primary objective is to compare the characteristics of ancestral lineages of mycobacterium tuberculosis complex, such as m. africanum west african 1 (lineage 5), with modern m. tuberculosis in benin. this study will build on the system of nationwide surveillance already implemented for retreatment patients and recruit in addition a representative random sample of new patients. so for this study sputa from retreatment patients and from a sample of new patients, from the 24 tuberculosis (tb) clinics (centres de diagnostic et de traitement de la tuberculose) selected all over the country (benin), will be shipped from tb clinics to the ''laboratoire de référence des mycobactéries'' (lrm), cotonou (national reference laboratory for mycobacteria, cotonou) if they consent. all retreatment patients will be recruited into the study and each 4 new patients detected after detection of a retreatment patient will also be recruited into the study. at enrolment, a questionnaire will be used to collect from consenting participants information such as: participant place of residence (rural or urban as determined by population density); ethnic group; age; sex; human immuno-deficiency virus (hiv) status; bacillus calmette guerin (bcg) vaccine scar... spoligotype analysis will be used to determine the population structure, as it allows the classification of most mycobacterium tuberculosis complex isolates in lineages, including strains with single or few copies of is6110. the external quality evaluation (assurance quality) of the laboratory analyses to be performed at the lrm (national reference laboratory for mycobacteria) in cotonou, benin during the study, will be performed by the institute of tropical medicine of antwerp in belgium.

Eligibility criteria:
inclusion criteria: * new or retreatment tuberculosis patients with acid fast bacilli-positive microscopy, * diagnosed in a participating tb clinic of benin, * aged ≥15 years (patients aged less than 15 years old will not be included in this study as acid-fast-bacilli microscopy is rarely positive in children) * who has given his/her informed consent (if adult potential participant:≥18 years old) or who has given his/her assent in addition to the informed consent of his/her legal representative (if potential participant aged 15-\<18 years) exclusion criteria: * extra-pulmonary tb only, * new patient who has started taking the tb treatment drugs. * retreatment patient who has started taking the tb retreatment drugs. * very low sputum quantity (at least 5 milliliters total sputum is acceptable) and potential participant refusing to give more sputum

Keywords: tuberculosis population structure implications lineages spoligotyping sputum resistance culture diagnostics outcome new/retreatment patient