title: A comparative study of the diagnostic methods for Group A streptococcal sore throat in two reference hospitals in Yaounde, Cameroon.
abstract: BACKGROUND
  Sore throat is a common complaint in general practice which is more frequent in children. The most frequent pathogenic bacteria associated with this infection is Streptococcus pyogenes. Rapid Antigen Diagnostic Test (RADT) facilitates the rapid identification and consequently prompt treatment of patients, prevents complications, and also reduces the risk of spread of Group A Streptococcus (GAS). The main objective of this study was to assess the diagnostic value of a rapid streptococcal antigen detection test in patients with sore throat.
  
  
  METHODS
  A cross-sectional descriptive study was carried out from January to April 2011 on patients aged 3 to 72 years consulting for pharyngitis or sore throat at the paediatric and Ear, Nose and Throat units of the University Teaching Hospital Yaounde and the Central Hospital Yaounde. Two throat swabs were collected per patient. One was used for the rapid test and the other for standard bacteriological analysis.
  
  
  RESULTS
  The prevalence of GAS in the study population was 22.5%. Out of the 71 samples collected, the RADT detected group A streptococcal antigens in 12 of 16 positive cultures giving a sensitivity of 75%. The specificity of the rapid test was 96%, with positive predictive value of 85.7%, and negative predictive value of 93% respectively.
  
  
  CONCLUSIONS
  Rapid test may have an additional value in the management of patients with high risk of having GAS infection. However, tests with a higher sensitivity are needed for accurate and reliable results for early diagnosis of patients with sore throat caused by GAS.
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon; Bacteriological Laboratory, Yaoundé University Teaching Hospital, Yaoundé, Cameroun.
authors.forename: Hortense Kamga
authors.initials: HK
authors.lastname: Gonsu
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon.
authors.forename: Cynthia Mbimenyuy
authors.initials: CM
authors.lastname: Bomki
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon; Ear, Nose and Throat Unit, Yaoundé University Teaching Hospital, Yaoundé, Cameroun.
authors.forename: François
authors.initials: F
authors.lastname: Djomou
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon.
authors.forename: Michel
authors.initials: M
authors.lastname: Toukam
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon.
authors.forename: Valantine Ngum
authors.initials: VN
authors.lastname: Ndze
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon.
authors.forename: Emilia Enjema
authors.initials: EE
authors.lastname: Lyonga
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon.
authors.forename: Calixte Didier
authors.initials: CD
authors.lastname: Mbakop
authors.affiliation: Department of Microbiology, Haematology, Parasitology and Infectious diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaounde, Cameroon.
authors.forename: Sinata
authors.initials: S
authors.lastname: Koulla-Shiro
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001431:Bacteriological Techniques / Q000379:methods*; D002163:Cameroon; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010612:Pharyngitis / Q000175:diagnosis* / Q000382:microbiology; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013290:Streptococcal Infections / Q000175:diagnosis* / Q000382:microbiology; D013297:Streptococcus pyogenes / Q000302:isolation & purification*; D055815:Young Adult
keywords: Cameroon; Group A-beta hemolytic streptococcus; rapid antigen diagnostic test; sensitivity; sore throat; specificity