Occurrence of group A ß-hemolytic streptococcal pharyngitis in the four months after treatment of an index episode with amoxicillin once-daily or twice-daily or with cephalexin.

BACKGROUND: Prospective studies using bacterial eradication as the endpoint have demonstrated that once-daily amoxicillin is as effective as twice-daily amoxicillin for treatment of group A ß-hemolytic streptococcal (GABHS) pharyngitis. OBJECTIVE: The aim of this study was to determine, in a retrospective study, whether treatment of symptomatic GABHS pharyngitis with once-daily amoxicillin was as effective in preventing clinical recurrences as twice-daily amoxicillin or cephalexin in pediatric office practice, using patient-initiated return visits for streptococcal pharyngitis as a pragmatic, clinical endpoint. METHODS: The charts of consecutive patients 2 years of age and older with laboratory-proven GABHS pharyngitis for a period of 2 years were reviewed to identify index cases of streptococcal pharyngitis and subsequent episodes. Age, weight, antibiotic treatment and time from index to subsequent episodes of GABHS pharyngitis were recorded. RESULTS: In 1402 index episodes, patients received amoxicillin once-daily (231), amoxicillin twice-daily (846) or cephalexin (325). The risk of symptomatic streptococcal pharyngitis in the 4 months after treatment of the index episode was not statistically different among the 3 treatment groups: amoxicillin once-daily (15.1%), amoxicillin twice-daily (19.6%) and cephalexin (19.1%). There was a trend toward reduction in the risk of recurrences in the 6 weeks after completion of antibiotics in the cephalexin (9%) group compared with the combined amoxicillin (13%) groups. CONCLUSIONS: Amoxicillin once-daily or twice-daily was equally effective in terms of frequency of recurrence of symptomatic GABHS pharyngitis.

Sensitivity of a rapid antigen detection test for group A streptococci in a private pediatric office setting: answering the Red Book's request for validation.

In the office laboratory of our private practice, the sensitivity of a single rapid antigen detection (RAD) test for group A streptococci (compared with backup throat culture) was examined over 3 winter periods. When cultures were held only 24 hours, the sensitivity was 92%; in the second period, when cultures were held to 48 hours, the sensitivity declined significantly to 86%; when the cultures were read without knowledge of the RAD test result, the sensitivity was 85%. As the Red Book Committee has suggested, physician office laboratories should validate the sensitivity of their RAD test against culture onto blood agar before abandoning the backup throat culture.