Bacteriological and clinical efficacy of various antibiotics used in the treatment of streptococcal pharyngitis in Italy. An epidemiological study.
A total of 123 community paediatricians and 23 microbiology laboratories studied the clinical and bacteriological efficacy of treatment of group A streptococcal pharyngitis in Italy. Of 1065 patients, from whom Streptococcus pyogenes was isolated, 723 returned to follow up and of these 138 (19%) still had a positive throat culture. The erythromycin resistance (ER) rate was 23.7% with resistance phenotype distribution of: 31.7% constitutive (CR), 26.6% inducible (IR) and 41.7% efflux pump (M) resistance phenotype. All strains were susceptible to the beta-lactam agents tested. CR strains were highly resistant to all 14, 15 and 16 membered macrolides with the exception of rokitamycin which showed activity against 37.8% of isolates. All phenotype M and some IR isolates were susceptible to clindamycin, rokitamycin, josamycin and spiramycin; clarithromycin was active against a small percentage of strains belonging to the IR and M phenotype. Bacterial eradication was found in 85.5, 78.7 and 75.8% of the penicillin, macrolide and cephalosporin treated groups. Genotyping of strains showed that 8.7% of the 19% of cases classified as 'failed bacterial eradication' were due to recolonization with a different isolate, observed exclusively among beta-lactams treated patients. Clinical cure was achieved in a high percentage of cases, irrespective of the antibiotic prescribed, with the best clinical efficacy being found following therapy with amoxycillin and clarithromycin (90.9%).
Rondini
G
G
Div. Pat. Neonatale OSM IRCCS, University of Pavia, Pavia, Italy.
Cocuzza
C E
CE
Cianflone
M
M
Lanzafame
A
A
Santini
L
L
Mattina
R
R
D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004352:Drug Resistance, Microbial; D004917:Erythromycin / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007558:Italy; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology / Q000627:therapeutic use; D010612:Pharyngitis / Q000188:drug therapy* / Q000382:microbiology; D010614:Pharynx / Q000382:microbiology*; D013290:Streptococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D013297:Streptococcus pyogenes / Q000187:drug effects* / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D010406:Penicillins; D004917:Erythromycin