Centor criteria

Streptococcus pyogenes

The Centor Criteria are a set of criteria which may be used to identify the likelihood of a bacterial infection in patients complaining of a sore throat. They were developed as a method to quickly diagnose the presence of Group A streptococcal infection or diagnosis of Streptococcal Pharyngitis in "adult patients who presented to an urban emergency room complaining of a sore throat."

Criteria

The patients are judged on four criteria, with one point added for each positive criterion:

• History of fever
• Tonsillar exudates
• Tender anterior cervical adenopathy
• Absence of cough

The Modified Centor Criteria add the patient's age to the criteria:

• Age <15 add 1 point
• Age >44 subtract 1 point

The point system is important in that it dictates management. Guidelines for management state:

• <2 points - No antibiotic or throat culture necessary (Risk of strep. infection <10%)
• 2-3 points - Should receive a throat culture and treat with an antibiotic if culture is positive (Risk of strep. infection 32% if 3 criteria, 15% if 2)
• >3 points - Treat empirically with an antibiotic (Risk of strep. infection 56%)

The presence of all four variables indicates a 40 - 60% positive predictive value for a culture of the throat to test positive for Group A Streptococcus bacteria. The absence of all four variables indicates a negative predictive value of greater than 80%. The high negative predictive value suggests that the Centor Criteria can be more effectively used for ruling out strep throat than for diagnosing strep throat.^{[citation needed]}

References

• Chan TV (September 2010). "The Patient with Sore Throat". Medical Clinics of North America 94 (5): 923–943. PMID 20736104.