Centor criteria to aid diagnosis of Group A beta-haemolytic streptococcus

Centor criteria to aid diagnosis of Group A beta-haemolytic streptococcus (GABHS)as a cause of presentation with a sore throat:

• tonsillar exudate
• tender anterior cervical lymph nodes
• absence of cough
• history of fever
• presence of three or four of these clinical signs suggests that the chance of the patient having GABHS is between 40% and 60%, so the patient may benefit from antibiotic treatment
• absence of three or four of the signs suggests that there is an 80% chance that the patient doesn't have the infection, and antibiotics are unlikely to be necessary
• in patients with tonsillitis who are unwell, and have three out of four of these criteria, the risk of quinsy is 1:60 compared with 1:400 in those who are not unwell
• centor criteria is not ideal, and will lead to some patients with bacterial pharyngitis not being treated and result in unnecessary antibiotic treatment for others

Reference:

1. MeReC Bulletin 2006;17(3):12-14.