Association between C-reactive protein rapid test and group A streptococcus infection in acute pharyngitis

Introduction: the diagnosis of streptococcal infection is usually made with the use of centor criteria,but some family doctors also rely on the determination of c-reactive protein (crp) to guide antibiotic therapy. methods: this was an observational study conducted in a health center. adults with acute pharyngitis and the presence of the 4 centor criteria (tonsillar exudates,tender cervical glands,history of fever,and absence of cough) were recruited. the patients underwent a pharyngotonsillar swab for microbiologic study and a crp rapid test during the consultation. results: a total of 149 patients were enrolled. the most frequent etiology was group a streptococcus,present in 83 cases (55.7%). the highest crp concentration was observed among patients with group c streptococcus infection,with a mean of 56.3 mg/l (95% confidence interval,25.7- 86.5 mg/l). for patients with group a streptococcus infection,the mean crp value was 34.4 (95% confidence interval,25.6-43.3 mg/l). conclusion: crp concentrations are not associated with group a streptococcus infection in patients with acute pharyngitis. the use of this point of care test is therefore not useful for distinguishing patients who require antibiotic therapy.