title: Correlation of Pseudomonas aeruginosa genotype with antibiotic susceptibility and clinical features of induced central keratitis.
abstract: OBJECTIVE
  To determine the association of type III secretion system (T3SS) genotype with antibiotic susceptibility, serotypes, and clinical manifestation of centrally located Pseudomonas aeruginosa keratitis.
  
  
  METHODS
  Clinical characteristics of P. aeruginosa keratitis cases from 2001 to 2011 were analyzed. Each strain was serotyped and genotyped for T3SS exotoxin genes. Antibiotic sensitivity and minimum inhibitory concentrations were determined with agar dilution method. Prognostic factors affecting final visual outcomes and time to re-epithelialization were analyzed using linear and Cox regression models.
  
  
  RESULTS
  Forty-four invasive and 28 cytotoxic strains were identified. Invasive strains occurred mostly in males (P = 0.03) with older age (P = 0.009) and ocular surgery or trauma history (P = 0.006), poor presenting (P = 0.04) and final (P < 0.0001) best spectacle-corrected visual acuity (BSCVA), and larger infiltration size (P = 0.03). Cytotoxic strains were associated with contact lens wear (P < 0.0001). Poor prognostic factors for final BCVA after adjusting for sex, age, and contact lens wear included invasive strains (P = 0.02), larger infiltration area (P = 0.02), deeper infiltrations (P = 0.02), and presence of hypopyon (P = 0.09). Factors affecting complete re-epithelialization time included invasive strains (P = 0.02), infiltration area (P = 0.01), depth (P = 0.02), and hypopyon (P = 0.03) after adjusting for age and sex. Serotypes 2, 6, and 11 were more commonly found among all isolates. A trend to increased fluroquinolone resistance is noted for invasive strains, although not reaching statistically significant difference.
  
  
  CONCLUSIONS
  Cytotoxic strains are associated with contact lens wear while invasive strains are related to poor prognosis and increased resistance to fluoroquinolones. Clinicians should be aware of the two different genotypes of P. aeruginosa affecting prognosis.
authors.affiliation: Department of Ophthalmology, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, Taipei, Taiwan Department of Ophthalmology, National Taiwan University Hospital, Medical College, National Taiwan University, Taipei, Taiwan.
authors.forename: Elizabeth P
authors.initials: EP
authors.lastname: Shen
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Medical College, National Taiwan University, Taipei, Taiwan.
authors.forename: Yi-Ting
authors.initials: YT
authors.lastname: Hsieh
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Medical College, National Taiwan University, Taipei, Taiwan.
authors.forename: Hsiao-Sang
authors.initials: HS
authors.lastname: Chu
authors.affiliation: Department of Infectious Disease, Department of Internal Medicine, National Taiwan University Hospital, Medical College, National Taiwan University, Taipei, Taiwan.
authors.forename: Shan-Chwen
authors.initials: SC
authors.lastname: Chang
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Medical College, National Taiwan University, Taipei, Taiwan.
authors.forename: Fung-Rong
authors.initials: FR
authors.lastname: Hu
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D003315:Cornea / Q000382:microbiology* / Q000473:pathology; D004269:DNA, Bacterial / Q000235:genetics*; D015818:Eye Infections, Bacterial / Q000188:drug therapy / Q000235:genetics* / Q000382:microbiology; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D007634:Keratitis / Q000188:drug therapy / Q000235:genetics* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D011552:Pseudomonas Infections / Q000188:drug therapy / Q000235:genetics* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000302:isolation & purification; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial
keywords: P. aeruginosa; antibiotic sensitivity; clinical outcome; serotype; type III secretion system