title: Phenoxymethyl penicillin versus co-amoxiclav in the treatment of acute streptococcal pharyngitis, and the role of beta-lactamase activity in saliva.
abstract: One hundred and sixty-five consecutive patients ( > 2 years of age) with acute group A streptococcal (GAS) pharyngitis randomly received co-amoxyclav (79 patients) or phenoxymethyl penicillin (86 patients). beta-Lactamase activity in saliva was determined for each patient. At follow up after seven days, tonsillar cultures from seven patients (9.6%) in the penicillin V group grew group A streptococcus; three of these patients had tonsillitis clinically. In the co-amoxiclav group these figures were three (3.8%) and two respectively (P > 0.05). Within the 12 month follow up period, there were four clinical recurrences (6.1%) in the penicillin V group and seven (9.3%) in the co-amoxiclav group (P > 0.1). beta-Lactamase activity in the saliva was demonstrated in 29 patients (19.2%). Fourteen (74%) of 19 bacteriological failures or clinical recurrences had beta-lactamase activity, versus 15 (12%) of 129 successfully treated patients (P < 0.001). There is no evidence that oral co-amoxiclav is better than oral penicillin V for the first treatment of acute GAS pharyngitis, but bacteriological failure and clinical recurrence are strongly associated with the presence of beta-lactamase activity in commensal flora.
authors.affiliation: Infection Unit, Aberdeen Royal Infirmary NHS Trust, Forresterhill, UK.
authors.forename: R S
authors.initials: RS
authors.lastname: Dykhuizen
authors.forename: D
authors.initials: D
authors.lastname: Golder
authors.forename: T M
authors.initials: TM
authors.lastname: Reid
authors.forename: I M
authors.initials: IM
authors.lastname: Gould
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000658:Amoxicillin / Q000627:therapeutic use; D019980:Amoxicillin-Potassium Clavulanate Combination; D002648:Child; D002675:Child, Preschool; D002969:Clavulanic Acids / Q000627:therapeutic use; D004359:Drug Therapy, Combination / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010404:Penicillin V / Q000627:therapeutic use*; D010406:Penicillins / Q000627:therapeutic use*; D010612:Pharyngitis / Q000188:drug therapy*; D012463:Saliva / Q000201:enzymology*; D013290:Streptococcal Infections / Q000188:drug therapy*; D001618:beta-Lactamases / Q000502:physiology*
chemical_list: D002969:Clavulanic Acids; D010406:Penicillins; D019980:Amoxicillin-Potassium Clavulanate Combination; D000658:Amoxicillin; D001618:beta-Lactamases; D010404:Penicillin V