title: Postoperative endophthalmitis: incidence, predisposing surgery, clinical course and outcome.
abstract: OBJECTIVE
  To describe the predisposing surgery, clinical course and final visual outcome for patients with culture-proven and culture-negative postoperative endophthalmitis.
  
  
  METHODS
  Case series.
  
  
  METHODS
  University-affiliated teaching hospital in Toronto.
  
  
  METHODS
  A total of 164 patients with clinically suspected postoperative endophthalmitis admitted between January 1989 and March 1996.
  
  
  METHODS
  Type of surgery, clinical presentation, culture results, infecting organism, treatment and final visual outcome.
  
  
  RESULTS
  An infectious agent was identified in 99 cases (60%). The organism most commonly isolated was coagulase-negative Staphylococcus (59 cases [60%]). In the culture-proven group cataract extraction was the most common predisposing surgical procedure, accounting for 85 cases (extracapsular cataract extraction [ECCE] in 60 cases and phacoemulsification in 25). The incidence rates of culture-proven endophthalmitis over the study period at our institution were 0.22% for ECCE and 0.30% for phacoemulsification. Of the 99 patients with culture-proven endophthalmitis 94 received intravitreal injections of antibiotics and 52 underwent vitrectomy. Of the 83 patients in this group for whom the final outcome was known, 29 (35%) had a visual acuity of 20/50 or better, and 15 (18%) had a vision of no light perception, with four eyes undergoing enucleation. Infection with organisms of low virulence (coagulase-negative Staphylococcus or Propionibacterium acnes) was associated with higher rates of 20/50 or better visual acuity compared with more virulent organisms (Staphylococcus aureus, streptococcal species and gram-negative bacilli) (46% vs. 10%) (p < 0.05). The culture-negative group had a significantly lower frequency of hypopyon on presentation (55% vs. 85%) and final outcome of no light perception (2% vs. 18%) (p < 0.01) than the culture-proven group.
  
  
  CONCLUSIONS
  Endophthalmitis was most common after cataract surgery. The rates of endophthalmitis after ECCE and phacoemulsification were similar. Postoperative endophthalmitis caused by organisms other than coagulase-negative Staphylococcus or P. acnes carries a poor visual outcome.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, University of Toronto, Toronto Hospital, Ont.
authors.forename: S
authors.initials: S
authors.lastname: Somani
authors.forename: A
authors.initials: A
authors.lastname: Grinbaum
authors.forename: A R
authors.initials: AR
authors.lastname: Slomovic
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001082:Aqueous Humor / Q000382:microbiology; D001419:Bacteria / Q000302:isolation & purification; D009877:Endophthalmitis / Q000453:epidemiology* / Q000382:microbiology / Q000628:therapy; D015818:Eye Infections, Bacterial / Q000453:epidemiology* / Q000209:etiology / Q000628:therapy; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000382:microbiology / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014792:Visual Acuity; D014821:Vitrectomy; D014822:Vitreous Body / Q000382:microbiology / Q000601:surgery
chemical_list: D000900:Anti-Bacterial Agents