IN a large-scale Swedish study of peritonsillar abscess (PTA), researchers found that the bacterium Fusobacterium necrophorum was not only the most commonly identified pathogen but also the only one significantly associated with post-treatment complications. This key finding could influence how U.S. clinicians approach microbiological testing and risk assessment in patients presenting with this common deep neck infection.
The retrospective observational study examined 637 patients across the Skåne Region of Sweden, all diagnosed with PTA between 2016 and 2020. Each patient underwent testing for both ß-hemolytic streptococci via culture and F. necrophorum using PCR. Patients with recent purulent complications or antibiotic use within 30 days were excluded to ensure cleaner microbial associations.
Among the identified pathogens, F. necrophorum was present in 33 percent of cases, making it more prevalent than Group A streptococci (28 percent) and Group C/G streptococci (6 percent). Notably, F. necrophorum was most commonly found in adolescents and young adults, a population often overlooked for deep tissue infections beyond typical pharyngitis.
Crucially, F. necrophorum was the only organism linked to both early (within 30 days) and late (1 to 6 months) complications, which included recurrent abscesses, other pharyngeal abscesses, and septic events. The odds ratio for early complications in patients infected with F. necrophorum was 3.8 (95% CI: 2.0–7.1), while the risk for late complications carried an odds ratio of 2.5 (95% CI: 1.3–4.9).
These findings suggest that identifying F. necrophorum in PTA may have prognostic implications and raise questions about whether more aggressive monitoring or different antibiotic strategies are warranted in such cases. For U.S. healthcare professionals, particularly those in emergency and ENT settings, the study underscores the importance of routine PCR testing for F. necrophorum in PTA patients, especially younger individuals.
Reference:
Lindberg E et al. Association between clinical outcome and microbiological findings in peritonsillar abscess. Eur J Clin Microbiol Infect Dis. 2025. doi: 10.1007/s10096-025-05156-y.
