In medical school we spend little time learning about sore throats. After all, it’s just a sore throat.
Group A beta-hemolytic streptococcal (GAS) tonsillitis dominates our sore throat concern, because it can cause acute rheumatic fever and peritonsillar abscess. We have rapid antigen tests for GAS so that we can treat patients with that infection.
But most studies and guidelines for sore throats have used data from pre-adolescents, and perhaps these studies and guidelines need reconsideration for adolescents and young adults. For simplicity, we will refer to the 15-30 age group as adults in this discussion.
Careful consideration of adult pharyngitis reveals significant differences from pre-adolescents. Adults have significantly lower GAS infection and carrier rates than pre-adolescents. Zwart showed that adults with Centor Scores of 3 or 4 (1 point each for tonsillar exudates, swollen tender anterior cervical adenopathy, lack of cough and fever history) had a 2-day clinical benefit from penicillin if they had GAS infection, while in a similar study of pre-adolescents, penicillin did not provide a clinical benefit.
While pre-adolescents get EBV infections, they do not get the infectious mononucleosis syndrome like adults do. Two bacteria cause pharyngitis in adults, but rarely in kids: Streptococcus dysgalactiae subsp. equisimilis (Group C or G beta-hemolytic streptococcus) and Fusobacterium necrophorum (FN). Both bacteria have similar clinical presentations to GAS. Both bacteria can cause suppurative complications. Recent data suggest that FN is the most common bacteria causing peritonsillar abscesses in adults. FN also causes a devastating suppurative complication—the Lemierre Syndrome (suppurative internal jugular thrombophlebitis and septic emboli following tonsillitis).
Unfortunately, diagnosing FN is difficult, as it is an anaerobic bacteria that does not grow on routine throat cultures. We have no rapid test for this bacterial infection.
So what should we do to manage sore throats? First, the recommendations for kids make sense. We can follow the guidelines and do testing (rapid antigen testing with backup cultures for GAS), treating only the GAS positive patients. However, adults deserve a different strategy.
Many experts have written that we have no evidence that treating Group C/G strep or FN would prevent suppurative complications. The logic of this rationale is flawed. The lack of evidence that treating a bacterial infection will prevent spread and suppurative complications does not imply evidence against treating such an infection.
The Cochrane Collaboration review on treating tonsillitis includes this: “Antibiotics reduced the incidence of … quinsy [peritonsillar abscess] within two months (RR 0.15; 95% CI 0.05 to 0.47) compared to those taking placebo.” This finding was independent of bacterial etiology. So we do have some evidence that narrow spectrum antibiotics should decrease suppurative complications. Since the Lemierre Syndrome can follow peritonsillar abscess, it follows that antibiotics likely will decrease Lemierre Syndrome incidence.
The rationale for limiting antibiotics in adult pharyngitis stems from a belief that we would encourage massive antibiotic use without great benefit. But narrow spectrum antibiotics (preferably penicillin) should not induce resistance, as most bacteria have already developed such resistance. If we started empirically treating adults with scores of 3 or 4, we are only talking about approximately 30% of adults seeking sore throat care. Withholding antibiotics from these young adults puts them at risk from serious suppurative complications. For these patients, empiric antibiotics make clinical sense.
About The Author:
Robert M. Centor, MD, is the retired regional dean for the Huntsville Regional Medical and professor of medicine in the Division of General Internal Medicine at the University of Alabama at Birmingham. He researches medical decision-making and has published widely in the diagnosis and management of adult sore throats. Dr. Centor is also Chair Emeritus of the Board of Regents for the American College of Physicians.