title: Infectious crystalline keratopathy due to Streptococcus pneumoniae. Possible association with serotype.
abstract: BACKGROUND
  Infectious crystalline keratopathy is a distinctive clinical entity characterized by bacterial replication within the corena without inflammation. The authors report on a patient with infectious crystalline keratopathy due to Streptococcus pneumoniae serotype 11F. They used this isolate to study the contribution of the pneumococcal polysaccharide capsule to the pathogenesis of the infectious crystalline keratopathy.
  
  
  METHODS
  Aliquots containing 10(6) colony-forming units of pneumococci serotype 11F, serogroup 9 or 15, were inoculated into New Zealand white rabbit corneas. The corneas were examined at 24, 48, and 72 hours. Representative corneas were excised at 24 hours and processed for histopathologic analysis.
  
  
  RESULTS
  Pauci-inflammatory crystalline lesions developed in all corneas inoculated with the serotype 11F ocular isolate by 24 hours. Suppurative keratitis developed in control corneas inoculated with serogroup 9 or 15 pneumococci. The nonocular 11F isolates produced lesions with some features compatible with infectious crystalline keratopathy.
  
  
  CONCLUSIONS
  Different pneumococcal serotypes vary in their ability to produce infectious crystalline keratopathy. Because serotype differences reflect differences in the antigenic polysaccharides of the bacterial capsule, this study suggests that properties of the pneumococcal capsule may influence the initial development of infectious crystalline keratopathy.
authors.affiliation: Veterans Affairs Medical Center, Houston, TX.
authors.forename: A Y
authors.initials: AY
authors.lastname: Matoba
authors.forename: T P
authors.initials: TP
authors.lastname: O'Brien
authors.forename: K R
authors.initials: KR
authors.lastname: Wilhelmus
authors.forename: D B
authors.initials: DB
authors.lastname: Jones
mesh_terms: D000368:Aged; D000818:Animals; D003319:Corneal Stroma / Q000382:microbiology / Q000473:pathology; D015818:Eye Infections, Bacterial / Q000382:microbiology* / Q000473:pathology; D006801:Humans; D007634:Keratitis / Q000382:microbiology* / Q000473:pathology; D008297:Male; D008828:Microbiological Techniques; D011008:Pneumococcal Infections / Q000382:microbiology* / Q000473:pathology; D011817:Rabbits; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000302:isolation & purification