title: Microbiologic and histopathologic assessment of corneal biopsies in the evaluation of microbial keratitis.
abstract: OBJECTIVE
  To investigate the utility of corneal biopsy in the evaluation of infectious keratitis; to compare results of culture and histopathologic examination of the same specimens; to investigate potential factors related to positive biopsy results.
  
  
  METHODS
  Retrospective, observational case series.
  
  
  METHODS
  We reviewed medical records for all patients who underwent corneal biopsy because of infectious keratitis at the Jules Stein Eye Institute from June 1989 through June 2009. In general, biopsy specimens were both cultured and examined histopathologically. Lesion size, lesion progression, and interval from presentation to biopsy were analyzed as possible predictors of positive biopsies.
  
  
  RESULTS
  Organisms were identified in 20 of 48 (42%) consecutive biopsies (positive cultures in 9 of 47 cases [19%]; positive histopathologic examination in 19 of 47 cases [40%]). Culture and histopathologic results were concordant in 30 of 46 biopsies (65%) for which both techniques were performed; 10 of the 16 discordant cases were culture-negative/histopathology-positive, while the remaining 6 had positive but discordant results for the 2 techniques (cultures all showed bacteria; histopathologic examination showed fungi or cysts consistent with Acanthamoeba sp.). Corneal biopsy revealed microorganisms in 12 of 27 patients (44%) with negative cultures of corneal scrapings obtained at presentation. None of the potential risk factors was statistically associated with positive biopsies.
  
  
  CONCLUSIONS
  Corneal biopsy can be useful for identifying the cause of infectious keratitis in selected cases. Culture and histopathologic examination can provide complementary information, but discordant results may occur. Acanthamoebic and fungal infections are more likely to be identified by histopathologic examination.
authors.affiliation: Ocular Inflammatory Disease Center, Jules Stein Eye Institute, University of California Los Angeles, Los Angeles, California 90095-7003, USA.
authors.forename: Jared R
authors.initials: JR
authors.lastname: Younger
authors.forename: R Duncan
authors.initials: RD
authors.lastname: Johnson
authors.forename: Gary N
authors.initials: GN
authors.lastname: Holland
authors.forename: Jon P
authors.initials: JP
authors.lastname: Page
authors.forename: Richard L
authors.initials: RL
authors.lastname: Nepomuceno
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Glasgow
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Aldave
authors.forename: Fei
authors.initials: F
authors.lastname: Yu
authors.forename: Jason
authors.initials: J
authors.lastname: Litak
authors.forename: Bartly J
authors.initials: BJ
authors.lastname: Mondino
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000302:isolation & purification; D001431:Bacteriological Techniques; D001706:Biopsy; D003315:Cornea / Q000382:microbiology* / Q000473:pathology*; D003320:Corneal Ulcer / Q000382:microbiology* / Q000473:pathology*; D015818:Eye Infections, Bacterial / Q000382:microbiology / Q000473:pathology; D015821:Eye Infections, Fungal / Q000382:microbiology / Q000473:pathology; D005260:Female; D005658:Fungi / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors