A comparative study of the diagnostic methods for Group A streptococcal sore throat in two reference hospitals in Yaounde, Cameroon

Abstract

IntroductionSore 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.MethodsA 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.ResultsThe 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.ConclusionRapid 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.

Use of Bionexia Strep A Plus Rapid Antigen Test in the Identification of Group A Beta-Hemolytic Streptococci in Throat Swab Samples

“…Afrika'da yapılan bir çalışmada, GAS prevalansı %22.5 olarak belirlenmiştir (16) . Mısır'da 4-16 yaş arası hastaları kapsayan bir çalışmada ise GAS prevalansı %42.2 olarak bildirilmiştir (17) .…”

Β-Hemolytic STREPTOCOCCAL PHARYNGITIS

“…These outcomes contradict with foregoing studies, which comparatively reported stumpy specificity and sensitivity of brisk antigen test while juxtapose by throat culture. [17][18][19][21][22] Statistical contradictions might be result of different techniques of laboratory. For throat swab, throat culture and screening test, our technicians adopted standard techniques.…”

Evaluating the prevalence and antibiotics susceptibility profile of Streptococcus pyogenes among patients 5 – 20 years with acute bacterial pharyngitis attending the Limbe Regional Hospital, South West, Cameroon

“…The sample size was calculated using the population proportion formula which is based on the assumption of 5% error, 95% confident values (Z1-α/2=1.96) and 13.5% prevalence based on a similar study in Yaounde, Cameroon (Gonsu et al, 2015). The convenient samping method was used because we recruited the participants as they presented at the pediatric ward after diagnosis.…”

“…A study carried out in Cameroon by Hardis revealed that, streptococcal pharyngitis represent 8.49% of inflammation pathologies that affect the ear, nose and the throat. It was also revealed that, it is most frequent in age groups 3 -30 years (Gonsu et al, 2015). GAS transmission can be through direct contact, or food borne contamination or droplets from those with pharyngeal infection or colonization (Kebede et al, 2021a).…”