title: Relationship of Virulence Factors and Clinical Features in Keratitis Caused by Pseudomonas aeruginosa.
abstract: OBJECTIVE
  To examine bacterial virulence factors in Pseudomonas aeruginosa isolates from contact lens (CL) wearers and non-CL wearers with P. aeruginosa keratitis, and to investigate relationships between virulence factors and clinical features of keratitis.
  
  
  METHODS
  The study involved 25 subjects including 18 CL and 7 non-CL-related P. aeruginosa keratitis patients. Slit-lamp photographs of all subjects were captured, and the focus occupancy ratio (FOR) was defined as the total focus area/entire cornea area, using image processing software. Twenty-five clinical P. aeruginosa isolates from keratitis were assessed for protease production, elastase production, biofilm formation, bacterial swimming and swarming motility, cell surface hydrophobicity, and genes encoding the type III secretion system (TTSS) effectors (ExoU and ExoS).
  
  
  RESULTS
  Ring abscess was found in 9 of 18 CL-related P. aeruginosa keratitis cases (CL[+] ring[+] group) but not in another 9 cases (CL[+] ring[-] group). Expression or prevalence of virulence factors in P. aeruginosa isolates from the CL(+) ring(+) group, CL(+) ring(-) group, and CL(-) group were compared. The FOR for CL(+) ring(+) or CL(-) was higher than for CL(+) ring(-) (P < 0.05 and P < 0.01, respectively). The rate of positive swimming motility for CL(+) ring(+) or CL(-) was higher than for CL(+) ring(-) (P < 0.05), whereas the rate of positive swarming motility for CL(+) ring(+) was higher than for CL(+) ring(-) or CL(-) (P < 0.05). Prevalence of an exoS+/exoU-genotype for CL(+) ring(+) or CL(-) was higher than for CL(+) ring(-) (P < 0.05). In the CL-related group, expression of elastase and swarming motility significantly correlated with FOR.
  
  
  CONCLUSIONS
  Swimming motility, swarming motility, and TTSS ExoS could play a major role in the determination of clinical features of P. aeruginosa keratitis.
authors.affiliation: Department of Ophthalmology Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Oka
authors.affiliation: Department of Ophthalmology Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Ophthalmology Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Ishikawa
authors.affiliation: Department of Ophthalmology Ehime University Graduate School of Medicine, Toon, Ehime, Japan 2ROHTO Pharmaceutical Co., Ltd., Osaka, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamaguchi
authors.affiliation: Department of Microbiology and Infection Control Science, Kyoto Pharmaceutical University, Yamashina, Kyoto, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Hayashi
authors.affiliation: Department of Microbiology and Infection Control Science, Kyoto Pharmaceutical University, Yamashina, Kyoto, Japan.
authors.forename: Naomasa
authors.initials: N
authors.lastname: Gotoh
authors.affiliation: Department of Ophthalmology Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ohashi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018441:Biofilms; D003261:Contact Lenses / Q000009:adverse effects / Q000382:microbiology; D003315:Cornea / Q000382:microbiology / Q000473:pathology; D005260:Female; D006801:Humans; D007634:Keratitis / Q000382:microbiology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011552:Pseudomonas Infections / Q000382:microbiology* / Q000473:pathology; D011550:Pseudomonas aeruginosa / Q000472:pathogenicity; D066167:Slit Lamp; D037521:Virulence Factors / Q000502:physiology*; D055815:Young Adult
chemical_list: D037521:Virulence Factors