title: Intravenous treatment of experimental Staphylococcus aureus endophthalmitis: imipenem versus the combination of ceftazidime and amikacin.
abstract: BACKGROUND
  To compare the efficacy of intravenous (IV) imipenem (IPM) and a combination of IV ceftazidime (CAZ) and amikacin (AN) in the treatment of Staphylococcus aureus endophthalmitis in a rabbit model.
  
  
  METHODS
  Right eyes of 60 albino rabbits were injected with 1000 colony-forming units of S. aureus intravitreally. After 24 h, treatment with either IV IPM (37.5 mg/kg) every 8 h ( n=18) or IV CAZ (50 mg/kg) and AN (10 mg/kg) every 8 hours ( n=18) was begun and continued until the animals were killed at the indicated timepoints; 24 control animals received no treatment. The concentration of bacteria in the vitreous from six animals per group was determined microbiologically on days 2, 3, and 5 after infection, and histologic examination was performed on all eyes.
  
  
  RESULTS
  The number of eyes with positive cultures on day 5 was lower in the group that received IV IPM (2/6) compared with the IV CAZ/AN group (4/6) and the control group (6/6). For the culture-positive eyes, the bacterial concentrations were significantly lower for the IV IPM group compared with the IV CAZ/AN group on days 2 and 5 ( P<0.05 and P<0.0065, respectively), but not on day 3 ( P <0.8. Bacterial counts in both treatment groups were significantly lower than in the control group ( P<0.005). Eyes in all groups, however, showed severe intraocular inflammation.
  
  
  CONCLUSIONS
  IV IPM is more effective than is IV CAZ/AN in reducing the number of bacteria in an animal model of S.aureus endophthalmitis.
authors: Department of Ophthalmology, Ludwig-Maximilians-Universität, Mathildenstrasse 8, 80336 Munich, Germany.
authors: Michael
authors: M
authors: Engelbert
authors: Herminia
authors: H
authors: Miño de Kaspar
authors: Martina
authors: M
authors: Mette
authors: Martin
authors: M
authors: Thiel
authors: Christopher N
authors: CN
authors: Ta
authors: Thomas
authors: T
authors: Grasbon
authors: Markus
authors: M
authors: Schulze-Schwering
authors: Volker
authors: V
authors: Klauss
authors: Anselm
authors: A
authors: Kampik
mesh_terms: D000583:Amikacin / Q000627:therapeutic use*; D000818:Animals; D002442:Ceftazidime / Q000627:therapeutic use*; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination / Q000627:therapeutic use*; D009877:Endophthalmitis / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D015818:Eye Infections, Bacterial / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D015378:Imipenem / Q000627:therapeutic use*; D007275:Injections, Intravenous; D011817:Rabbits; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D013211:Staphylococcus aureus / Q000302:isolation & purification / Q000502:physiology; D014822:Vitreous Body / Q000382:microbiology
chemical_list: D015378:Imipenem; D000583:Amikacin; D002442:Ceftazidime