Polymerase Chain Reaction (PCR) provides a superior tool for the diagnosis of Pneumococcal Infection in Burkina Faso

Purpose of study: The aim of this study was to determine the value of real-time Polymerase Chain Reaction (rt-PCR) in the routine surveillance of pneumococcal meningitis in Burkina Faso, compared to standard methods of culture, Gram stain and latex agglutination assay. Materiel and methods: A total of 385 specimens of cerebrospinal fluid were analyzed by the three standard bacteriological methods (Gram stain, latex agglutination assay, and culture) and real-time Polymerase Chain Reaction. Results: Of 385 specimens analyzed by these methods, 204 S. pneumoniae were detected by one or more  methods. Gram stain detected 36.4% (140/385) Gram positive encapsulated diplococci; 37.7% (145/385) and 20.8% (80/385) of the specimens were positive for pneumococci by latex agglutination assay and culture. These specimens were tested with rt-PCR, which confirmed 51.2% (197/385) S. pneumoniae positive. The sensitivity and specificity of culture were 54.4% and 31.5%, respectively, and the sensitivity and specificity of rt-PCR were 96.6% and 100%, respectively. These results showed that rt-PCR was more sensitive than Gram stain ( p=0.0235 ), latex agglutination assay ( p=0.0442 )and culture ( p=0.0006 ).The culture is the gold standard method; however, the result showed that rt-PCR had specificity and was as specific as Gram stain ( p=0.3405 ) and latex agglutination assay ( p=0.7745 ). Conclusion: rt-PCR was highly sensitive and specific. It could be used as a complementary diagnostic tool to  mprove case confirmation of bacterial meningitis. However,its high cost, the qualification of the technical staff and infrastructures required for its implementation, constitute obstacles to its widened use in countries with limited resources. Keywords: Streptococcus pneumoniae , meningitis, rt-PCR, standard bacteriological methods Objectif: Le but de cette etude etait de determiner la place de la rt-PCR dans la surveillance de routine de meningitespneumococciquesau Burkina Faso et la comparee avec les methodes de la bacteriologie classique: Culture, coloration de Gram et l’agglutination au latex. Materiel etmethodes: Au total, 385 echantillons deliquides cephalorachidiens (LCR)etaient analyses par les trois methodes de la bacteriologie classique (coloration de Gram, agglutination au latex, culture) et la PCR en temps reel. RESULTATS: Parmi 385 echantillons analyses, 204 cas de Streptococcuspneumoniae etaient detectes par une ou plusieurs methodes. La coloration de Gram adetecte 36,4% (140/385) diplocoques encapsules a Gram positif (DGP); 37,7% (145/385) et 20,8% (80/385) d’echantillons etaient positifs aux pneumocoques par l’agglutination au latex et la culture. Ces echantillons etaient aussi testes par rt-PCR qui a confirme 51,2% (197/385) cas positifs de S. pneumoniae . La sensibilite et la specificite de la culture etaient respectivement de 54,4% et 31,5%, et la sensibilite et la specificite de rt-PCR etaient respectivement de 96,6% et 100%. Ces resultats ont montre que la rt-PCR etait plus sensible que la coloration de Gram ( p=0,0235 ), l’agglutination au latex ( p=0,0442 ) et la  culture( p=0,0006 ).La culture est une methode de reference; cependant, le resultat a montre que rt-PCR etait plus sensibleet aussi specifique que la coloration de Gram (( p=0,3405 )et l’agglutination au latex ( p=0,7745 ). Conclusion : :rt-PCR etait plus sensible et plus specifique. Elle pourrait etre utilisee comme un outil de diagnostic complementaire pour ameliorer les cas de confirmation de meningites bacteriennes. Cependant, ces couts de realisation, la qualification de techniciens et les materiels pour son application constituent des obstacles pour sa vulgarisation dans les pays a ressources limites. Keywords: Streptococcus pneumoniae , meningites, rt-PCR, methodes de la bacteriologie classique Article in English.