Group A streptococcus-negative acute tonsillitis in primary care – a randomized controlled trial comparing phenoximethylpenicillin and no antibiotic treatment

Acute tonsillitis (AT) is a common reason for antibiotic prescribing in primary care. Guidelines focus on identifying and treating Group A streptococcus (GAS) when 3-4 Centor criteria are present.

However, etiological studies on AT show that other pathogens can also be present, and in clinical practice GAS-negative AT with severe symptoms, is often treated with phenoxymetylpenicillin (PcV) despite lack of evidence.The overall goal of this study is to optimize the use of antibiotics.

The specific aims are that in patients ≥15-years in primary care, with AT, 3-4 Centor criteria, negative for GASdetermine if PcV treatment shortens the time to recovery and reduces symptom intensity in patients with GAS-negative ATinvestigate the significance of pathogens other than GASThis is an open randomized controlled trial, where patients with non-GAS AT are randomized to receive either PcV 3 times daily for 10 days or no antibiotic treatment.

Blood samples are taken to measure the inflammatory and immunological response to infections.

Throat swabs are collected for culture of F. necrophorum and streptococci group C and G, as well as PCR for bacteria and viruses at inclusion and at follow up. Patients are requested to record symptoms in a diary for ten days. Follow-up visits are planned after 18-21 days, and by phone 1 and 3 months after inclusion.

Inclusion started before the pandemic and will tentatively continue until the spring of 2025 after which analysis and writing will follow.