Abstract
OBJECTIVE: This study aimed to assess the cause of acute pharyngitis and determine the duration of severe and moderate symptoms based on the aetiology. DESIGN: Prospective observational study. SITE: One urban health care centre. PARTICIPANTS: Patients aged 15 or older with acute pharyngitis were included. INTERVENTIONS: Bacterial identification was carried out in the microbiology lab using MALDI-TOF in two throat samples. Patients received a symptom diary to return after one week. MAIN MEASUREMENTS: Number of days with severe symptoms, scoring 5 or more in any of the symptoms included in the symptom diary, and moderate symptoms, scoring 3 or more. RESULTS: Among the 149 patients recruited, beta-haemolytic streptococcus group A (GABHS) was the most common aetiology. Symptoms and signs alone as well as the mean Centor score cannot distinguish between GABHS and other bacterial causes in patients with acute pharyngitis. However, there was a trend indicating that infections caused by Streptococcus dysgalactiae and Streptococcus agalactiae presented more severe symptoms, whereas infections attributed to the Streptococcus anginosus group, Fusobacterium spp., and those where oropharyngeal microbiota was isolated tended to have milder symptoms. S. dysgalactiae infections showed a trend towards longer severe and moderate symptom duration. CONCLUSION: GABHS was the most prevalent, but group C streptococcus caused more severe and prolonged symptoms.