title: The Eagle effect revisited: efficacy of clindamycin, erythromycin, and penicillin in the treatment of streptococcal myositis.
abstract: We investigated the relative efficacies of penicillin, clindamycin, and erythromycin in a mouse model of myositis due to Streptococcus pyogenes. Penicillin was ineffective unless given at the time of bacterial injection, and treatment delays of 2 h reduced its efficacy such that survival was no better than that of untreated control animals (P less than .05). Survival of erythromycin-treated mice was greater than that of both penicillin-treated mice and untreated controls, but only if treatment was begun within 2 h. Mice receiving clindamycin, however, had survival rates of 100%, 100%, 80%, and 70% even if treatment was delayed 0, 2, 6, and 16.5 h, respectively. Thus, clindamycin demonstrated superior efficacy to penicillin among all the various treatment groups (P less than .05). Our results corroborate the failure of penicillin in this model of streptococcal infection and suggest that, unlike penicillin, the efficacy of clindamycin is not adversely altered by the "Eagle effect."
authors.affiliation: Department of Medicine, Veterans Administration Medical Center, Boise, Idaho 83702.
authors.forename: D L
authors.initials: DL
authors.lastname: Stevens
authors.forename: A E
authors.initials: AE
authors.lastname: Gibbons
authors.forename: R
authors.initials: R
authors.lastname: Bergstrom
authors.forename: V
authors.initials: V
authors.lastname: Winn
mesh_terms: D000818:Animals; D002981:Clindamycin / Q000627:therapeutic use*; D004917:Erythromycin / Q000627:therapeutic use*; D005260:Female; D008297:Male; D051379:Mice; D009220:Myositis / Q000188:drug therapy*; D010406:Penicillins / Q000008:administration & dosage / Q000627:therapeutic use*; D013290:Streptococcal Infections / Q000188:drug therapy*; D013297:Streptococcus pyogenes
chemical_list: D010406:Penicillins; D002981:Clindamycin; D004917:Erythromycin