Efficacy of Penicillin versus Cefdinir in Eradication of Group A Streptococci and Tonsillar Flora

Abstract

Core tonsillar cultures were obtained from 40 children with recurrent tonsillitis treated with either penicillin or cefdinir. Group A beta-hemolytic streptococci were isolated from 11 penicillin-and 3 cefdinir-treated (P < 0.001) patients. ␤-Lactamase producers were recovered from 17 penicillin-and 3 cefdinir-treated (P < 0.01) patients. Inhibiting alpha-hemolytic streptococci were isolated less often from penicillin-treated patients than from cefdinir-treated patients.Penicillin failure to eradicate group A beta-hemolytic streptococci (GABHS) from inflamed tonsils is of great concern (8). One explanation of this phenomenon is that ␤-lactamase-producing bacteria (BLPB) protect GABHS by inactivating penicillin (1). Another explanation is that the preservation of alpha-hemolytic streptococci (AHS) that possess interfering capabilities against GABHS contribute to the eradication of this organism (13).Several classes of antimicrobials that are active against GABHS and BLPB are more effective than penicillin in eradicating GABHS from recurrently inflamed tonsils (1, 5, 7). A possible explanation for the improved efficacy of cephalosporins over penicillin is the activity of cephalosporins against BLPB and their relative inactivity against AHS.This study investigated the effects of penicillin and cefdinir therapies on the core tonsillar aerobic bacterial flora of children with recurrent tonsillitis.Patients consecutively scheduled for elective tonsillectomies because of recurrent GABHS tonsillitis were included. Criteria for inclusion were a history of recurrent GABHS pharyngotonsillitis (at least six episodes within the preceding 2 years, with at least four by GABHS) and an age of Ͼ4 years. Excluded were subjects who received antimicrobials or had any infection during the previous month. The study was performed between June 1998 and June 2002 and was approved by the Institutional Review Board. Each subject had general physical and otolaryngological examinations, a complete blood cell count, and urinalysis.Following a tonsillectomy, one tonsil was cauterized with a heated scalpel, and an incision was made through the area. The tonsillar core was swabbed with a sterile, cotton-tipped applicator that was placed onto an anaerobic transport medium (Port-A-Cul; BBL, Cockeysville, Md.) and inoculated within 24 h onto sheep's blood (5%), chocolate, and MacConkey agar plates (all media from BBL, Becton Dickinson Co., Cockeysville, Md.). The plates were incubated aerobically at 37°C (MacConkey) and under 5% CO 2 and were examined at 24 and 48 h (11). ␤-Lactamase activity was determined on five colonies of each morphological feature of all isolates by using a Cefinaz disk (BBL, Cockeysville, Md.).Inhibitory activities of five separate colonies of AHS from each patient were tested against one strain of a recent clinical isolate of GABHS. Minidrops of log-phase broth cultures of the isolates were transferred with a Steers steel pin replicator to vitamin K1-enriched Brucella blood agar plates and allowed to dry for 15 min. A log-ph...

Penicillin Failure in the Treatment of Acute and Relapsing Tonsillopharyngitis Is Associated With Copathogens and Alteration of Microbial Balance: A Role for Cephalosporins

“…41 Brook and Foote 41 compared 2 modes of therapy for relapsing tonsillitis due to GABHS: one using penicillin and the other an extended-spectrum cephalosporin (cefdinir). Both agents were administered for 10 days prior to surgery to children who suffered from recurrent GABHS tonsillitis and were scheduled for elective tonsillectomy.…”

Rate of eradication of group A beta-hemolytic streptococci in children with pharyngo-tonsillitis by amoxicillin and cefdinir

“…This may explain the superiority of shorter 5-day course of cephalosporins over 10 days of penicillins [6,7]. The faster efficacy of cefdinir may be due to its activity against BLPB recovered from patients (i.e., Staphylococcus aureus, Haemophilus influenzae and Moraxella catarrhalis) [8,9] and its relative lower activity against AHS (some of which possess interfering capability against GABHS). Furthermore, the fever reduction in those receiving cefdinir occurred a day earlier than in those getting amoxicillin.…”

Overcoming penicillin failures in the treatment of Group A streptococcal pharyngo-tonsillitis

“…The above selective activity of cephalosporins has been demonstrated in an animal model study of mixed infection [39], as well as in patients who were treated with an extended-spectrum cephalosporin prior to elective tonsillectomy [48]. Brook and Foote [48] compared two modes of therapy of relapsing tonsillitis due to GABHS: one using penicillin and the other using an extendedspectrum cephalosporin (cefdinir).…”

“…Penicillin is still used for the treatment of acute GABHS PT [45], despite its high failure rate [28,48,49], mainly because of its long track record and low cost. Often, amoxicillin is substituted for penicillin because of its better taste.…”

“…Brook and Foote [48] compared two modes of therapy of relapsing tonsillitis due to GABHS: one using penicillin and the other using an extendedspectrum cephalosporin (cefdinir). Both agents were administered for 10 days prior to surgery to children who suffered from recurrent GABHS tonsillitis and were scheduled for elective tonsillectomy.…”