A Potential Paradigm Shift for Strep Cultures?

In a study published a few days ago in the Annals of Internal Medicine, researchers discuss the prevalence of Fusobacterium necrophorum in students with pharyngitis. Typically, severe sore throats are attributed to Streptococcus Group A, C, or G; however, sometimes patients can be symptomatic but negative for these three pathogens. The study authors found F. necrophorum in 20.5% of their symptomatic population (312 students aged 15 to 30 years).

This study does raise an interesting question: should micro labs inoculate a CDC plate as well as a blood plate for strep cultures? This organism is susceptible to penicillin, so the treatment course is the same as for typical strep throat, which would indicate the CDC isn’t really needed. However, as this Healthday article indicates, F. necrophorum infections can lead to Lemierre’s syndrome, a rare but serious complication. Knowing the causative agent of a sore throat would be beneficial.

Swails

Kelly Swails, MT(ASCP), is a laboratory professional, recovering microbiologist, and web editor for Lab Medicine.