Beta-Hemolytic Nongroup A Streptococcal Pharyngitis in Children

To evaluate the epidemiology, clinical features, and antibiotic prescribing patterns for nongroup A streptococci (NGAS) in children.

Throat cultures obtained for pharyngitis were assessed at a large community-based health system over 10 years. Epidemiologic and clinical features of children with NGAS were compared with children with group A Streptococcus (GAS) and negative cultures. Antibiotic prescribing patterns were evaluated.

A total of 224 328 rapid streptococcal antigen tests and 116 578 throat cultures were performed. Clinical analysis was completed for 602 GAS-positive patients, 535 NGAS-positive patients, and 480 patients with negative cultures. Incidence of NGAS did not vary annually or by season but increased with age from 2% at ≤5 years to 7% at 18 years of age. Patients with NGAS were more likely than those with negative cultures to have tonsillar exudate (20.3% vs 13.1%, P = .003) and enlarged tonsils (28.6% vs 19.3%, P < .001). Modified Centor scores did not differ between groups (score ≥2, P = 1.0; score ≥3, P = .50). Patients with GAS were more likely than those with NGAS to have fever (32.6% vs 24.5%, P = .003), palatal petechiae (14.0% vs 3.1%, P < .001), and modified Centor score ≥2 (47.8% vs 27.1%; P < .001). Of patients with NGAS, 65% were prescribed antibiotics.

NGAS likely exist in both carriage and infectious states and incidence increases with age. Infections associated with NGAS are milder than with GAS, and complications are rare. Laboratory reporting of NGAS results in high antibiotic use, despite current recommendations against treatment.