Infections Associated with the Streptococcus Anginosus Group in Children.

Objectives: Streptococcus anginosus group (SAG), also known as the Streptococcus milleri group, consists of Streptococcus anginosus, Streptococcus intermedius and Streptococcus constellatus. Skin and soft tissue infections, intra-abdominal infections, skeletal infections and ear-nose-throat (ENT) and cervical infections are the most common presentations. This study aimed to evaluate SAG infections in children.

Methods: A retrospective review was conducted on patients aged 0-18 years who had cultures positive for S. anginosus, S. intermedius, or S. constellatus between January 1, 2019, and March 1, 2024.

Results: SAG bacteria were cultured in 113 patients. SAG was identified as the causative agent of infection in 93 patients. Of a total of 93 patients, 39 were female (41.9%) and 54 were male (58.1%). The median age of the patients at the time of diagnosis was 14 years (IQR: 9-17). Among these, S. constellatus was found in 46 patients (49.5%), S. anginosus in 36 patients (38.7%), and S. intermedius in 11 patients (11.8%). The infections presented primarily as skin and soft tissue infections (63 patients), head and neck infections (23 patients), and intra-abdominal abscesses (7 patients). Additionally, two patients had concomitant bacteremia. Predisposing factors for the development of infection were identified in 52 patients (55.3%). Surgical drainage was required for 70 patients (74.4%).

Conclusion: Streptococcus constellatus was the most frequently isolated species among the SAG, followed by S. anginosus and S. intermedius. The most common site of infection was skin and soft tissue, with a significant proportion of patients requiring surgical drainage. The overall incidence of bacteremia was low. S. intermedius was more frequently isolated from deep tissue infections.