468 TREATMENT (Rx) OF GROUP A STREPTOCOCCAL (GAS) PHARYNGITIS. RESULTS OF A PROSPECTIVE, RANDOMIZED STUDY OF 4 ANTIBIOTICS

Abstract

Penicillin V (P), benzathine/procaine penicillin (BP), cefadroxil (C), and erythromycin estolate (EE) were used for Rx of 198 children with GAS pharyngitis. Patients ranged in age from 2-15 years and all were symptomatic when Rx was started. Rx groups were similar with regard to age, sex, weight and duration of illness before Rx. All pts improved within 24 hours of initiation of Rx. At 5 days GAS were present in the throat cultures of 3 pts (2P, 1C); the serotypes of 2 organisms were identical to those isolated from pre-Rx cultures. Four days after Rx GAS were cultured from 3(6%) P-Rx'd pts, 1(2%) C pt, 1(2%) E pt, and 2(4%) BP pts. All were serotypically identical to the pre-Rx organisms. Two (21%) of these pts were symptomatic. GAS were isolated from 19 pts at 7-21 days after Rx; 12 of 19 had new serotypes and 11(91%) of these 12 were symptomatic. Excluding pts with new infections, the bacteriologic failure rates (relapse) during the 31-day study period were: 2%(EE), 6%(C), 12%(P) and 12%(BP). Eleven of 16(69%) children with relapse were asymptomatic at the time of recurrence. There were no significant differences in the rates of serologic conversion between symptomatic (82%) and asymptomatic (54%) children or between those with reinfection (77%) and those with relapse (63%). Antibiotic resistance of GAS, presence of penicillinase-producing staphylococci and lack of compliance were not related to relapse. These four antibiotics were equally effective in Rx of GAS pharyngitis.