title: The Endophthalmitis Vitrectomy Study. Relationship between clinical presentation and microbiologic spectrum.
abstract: OBJECTIVE
  The authors determine if specific features of the clinical presentation of acute postoperative endophthalmitis correlated with the microbiologic culture results.
  
  
  METHODS
  A total of 420 patients who had clinical evidence of endophthalmitis within 6 weeks after cataract surgery or secondary intraocular lens implantation were evaluated as part of a randomized clinical trial. Results of cultures performed on aqueous and vitreous specimens obtained at presentation were categorized as follows: gram-positive coagulase-negative micrococci, "other" gram-positive, gram-negative, and equivocal/no growth.
  
  
  RESULTS
  Eleven features of the initial clinical presentation were associated with significant differences in the microbiologic spectrum (P < 0.05). Baseline factors correlating with higher rates of both gram-negative and other gram-positive isolates were: corneal infiltrate, cataract wound abnormalities, afferent pupillary defect, loss of red reflex, initial light perception-only vision, and symptom onset within 2 days of surgery. Gram-negative organisms did not grow in any eyes in which a retinal vessel could be visualized, and 61.9% of these eyes had equivocal or no growth. Diabetes mellitus was associated with a higher yield of gram-positive, coagulase-negative micrococci. Eye pain was not a discriminator for culture results.
  
  
  CONCLUSIONS
  The presenting characteristics of acute endophthalmitis after cataract surgery may be helpful in predicting the most likely culture results. Such predictions do not appear sufficiently strong to guide the initial empiric choice of intravitreal antibiotics.
authors.affiliation: W. K. Kellogg Eye Center, University of Michigan, Ann Arbor, USA.
authors.forename: M W
authors.initials: MW
authors.lastname: Johnson
authors.forename: B H
authors.initials: BH
authors.lastname: Doft
authors.forename: S F
authors.initials: SF
authors.lastname: Kelsey
authors.forename: M
authors.initials: M
authors.lastname: Barza
authors.forename: L A
authors.initials: LA
authors.lastname: Wilson
authors.forename: C C
authors.initials: CC
authors.lastname: Barr
authors.forename: S R
authors.initials: SR
authors.lastname: Wisniewski
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001082:Aqueous Humor / Q000382:microbiology; D002387:Cataract Extraction / Q000009:adverse effects; D009877:Endophthalmitis / Q000382:microbiology* / Q000473:pathology* / Q000628:therapy; D015818:Eye Infections, Bacterial / Q000382:microbiology / Q000473:pathology / Q000628:therapy; D005260:Female; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D006801:Humans; D007910:Lenses, Intraocular / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D014821:Vitrectomy; D014822:Vitreous Body / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents