Clinical Perineal Streptococcal Infection in Children: Epidemiologic Features, Low Symptomatic Recurrence Rate after Treatment, and Risk Factors for Recurrence

ObjectivesTo evaluate the epidemiology of perineal streptococcal infection and recurrence rates following amoxicillin treatment.Study designWe used laboratory logs in a single pediatric practice to identify patients 0-18 years of age with perineal cultures positive for group A Streptococcus (GAS) and reviewed their medical charts. We described epidemiologic features, determined recurrence rates following antibiotic treatment, and performed a case-control study to identify possible risk factors for recurrence in patients treated with amoxicillin.ResultsWe found a perineal streptococcal infection rate of 4.6 per 10 000 patient encounters and a recurrence rate in 157 patients with perineal streptococcal infection of 12.4% after amoxicillin. In male patients, the predominant site of involvement was the perianal region (86%), and for female patients, the perivaginal area (62%). Nearly 80% of patients were 2-7 years of age (range 18 days-12.5 years). Perineal streptococcal infection and GAS pharyngitis followed a similar seasonal pattern of occurrence with 65% of perineal streptococcal infection occurring October through March. In patients with perineal streptococcal infection, 95% had a concomitant pharyngeal culture positive for GAS. Best predictive factors for recurrence after amoxicillin were longer duration of symptoms prior to diagnosis and having a sibling with perineal streptococcal infection at some time before or after the initial episode.ConclusionsFollowing treatment with amoxicillin, we found a low recurrence rate of 12.4%. Amoxicillin can be expected to be reliable first-line therapy for perineal streptococcal infection.