Physician urges changes in diagnosis for sore throat in young adults

Currently, physicians are taught to suspect group A streptococcal bacteria as the primary cause of pharyngitis. But according to findings published Dec. 1 in the Annals of Internal Medicine, physicians also should look for the presence of bacteria called Fusobacterium necrophorum when treating sore throat in young adults and adolescents that worsens or is strep-negative.

"F. necrophorum, which only has been recognized as a potential cause of pharyngitis in adolescents and young adults in the past five years, may cause up to 10 percent of sore throat in those 15-24 years of age," said Robert Centor, M.D., professor of internal medicine, associate dean of medicine at UAB and the paper's lead author. "More important, F. necrophorum is associated with a rare but life-threatening complication called Lemierre syndrome."

Lemierre syndrome mostly affects adolescents and young adults and rarely is seen in pre-adolescents. It begins with a sore throat, followed by an infected jugular vein after four to five days. Abscesses in other parts of the body may occur. Approximately 5 percent of people who get Lemierre syndrome die.

Group A strep also is associated with a serious complication -- rheumatic fever -- but the incidence rate of Lemierre syndrome following exposure to F. necrophorum is much higher and associated with greater morbidity and mortality.

"The risk of Lemierre syndrome exceeds the risk of acute rheumatic fever, which is the classic reason that physicians worry about sore throats," said Centor.

Centor said clinicians should expand their diagnostic process for adolescents and young adults with sore throat to consider F. necrophorum, especially if the sore throat does not improve within three to five days. Centor said physicians need to be aware of the red flags that might indicate Lemierre syndrome, including unilateral neck swelling, rigors, night sweats or high fevers. There is not a routine test for F. necrophorum pharyngitis and a CT scan is required to detect Lemierre syndrome

Aggressive treatment with antibiotics such as a combination of penicillin and metronidazole or with clindamycin alone is appropriate. Centor said he hopes this analysis will lead to better diagnostic tests for the presence of F. necrophorum.