Use of clinical scores such as the Centor criteria (which were designed to predict the presence of Lancefield group A β-haemolytic streptococci) or antigen tests in patients with sore throats have the potential to better target antibiotics, prevent progression of the illness and complications, improve symptom control, and reduce overall antibiotic use compared with empirical management strategies such as delayed prescribing or no offer of antibiotics.
This study compared three strategies for limiting or targeting antibiotic use in patients with sore throat: delayed antibiotic prescribing, the use of a clinical score designed to identify streptococcal infection, and the targeted use of rapid antigen tests according to the clinical score. Included patients were people aged ≥3 years presenting with acute sore throat (two weeks or less of sore throat) and an abnormal looking throat.
Delayed antibiotics consisted of a prescription being written for antibiotics and left in the surgery reception, with advice to the patient to collect the prescription after three to five days if symptoms were not starting to settle or were getting considerably worse.
The clinical score (FeverPAIN) was applied, and antibiotics were not offered to those with low scores (0/1). Immediate antibiotics were offered for those with high scores (≥4) and delayed antibiotics for those with intermediate scores (2 or 3).
The clinical score was used in all patients randomised to the rapid antigen test group. Those with low clinical scores (0/1) were not offered antibiotics or a rapid antigen test, those with a score of 2 were offered a delayed prescription, and those with higher scores (≥3) underwent a rapid antigen test on surgery premises. After the test, patients with negative results were not offered antibiotics.
The primary endpoint was symptom severity (mean score of soreness and difficulty swallowing in days 2–4). The authors reported that, compared with the control group, there were greater improvements in symptom severity for both the clinical score group (−0.33, 95% confidence interval −0.64 to −0.02) and the rapid antigen test group (−0.30, −0.61 to 0.004) (equivalent to 1 person in 3 rating sore throat and difficulty swallowing a slight rather than a moderately bad problem). Of the patients in the delayed prescribing group, 46% (74/164) reported using antibiotics. The other two groups had a lower use of antibiotics: compared with the delayed prescribing group there was an estimated 29% relative reduction in the clinical score group (risk ratio 0.71, 0.50 to 0.95) and a 27% relative reduction in the antigen test group (0.73, 0.52 to 0.98).
The authors concluded that compared with empirical delayed antibiotic prescribing for acute sore throat, use of a clinical score improves both reported symptoms and antibiotic use. Use of the clinical score combined with targeted use of a rapid antigen test provides similar benefits but with no clear advantages compared with use of a clinical score alone.
NICE guideline: Prescribing of antibiotics for self-limiting respiratory tract infections in adults and children in primary care recommends that a no antibiotic prescribing strategy or a delayed antibiotic prescribing strategy should be agreed for patients with the following conditions:
• acute otitis media
• acute sore throat/acute pharyngitis/acute tonsillitis
• common cold
• acute rhinosinusitis
• acute cough/acute bronchitis.
However, depending on clinical assessment of severity, patients may also be considered for an immediate antibiotic prescribing strategy if they have acute sore throat/acute pharyngitis/acute tonsillitis when three or more Centor criteria (presence of tonsillar exudate, tender anterior cervical lymphadenopathy or lymphadenitis, history of fever and an absence of cough) are present.