title: Acanthamoeba sclerokeratitis: epidemiology, clinical features, and treatment outcomes.
abstract: OBJECTIVE
  To describe the epidemiology, clinical features, and treatment outcomes of Acanthamoeba sclerokeratitis (ASK).
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  All cases of both Acanthamoeba keratitis (AK) and ASK identified between January 1, 2000, and January 8, 2011, at Moorfields Eye Hospital.
  
  
  METHODS
  Acanthamoeba keratitis was defined as the presence of AK with concurrent ipsilateral scleral inflammation. Topical steroids and oral nonsteroidal anti-inflammatory drugs (NSAIDs) were used as the first line of treatment. In unresponsive cases, oral NSAIDs were replaced by oral prednisolone with cyclosporine, azathioprine, or mycophenolate as steroid-sparing agents. Cyclosporine was combined with azathioprine or mycophenolate in cases unresponsive to only 1 of these drugs alone.
  
  
  METHODS
  Epidemiology, clinical phenotype, response to therapy, resolution of inflammation, visual outcome, corneal transplantation, and enucleation rate.
  
  
  RESULTS
  From a series of 178 patients with AK, 36 eyes of 33 patients (18.5%) developed ASK. A total of 25 of 33 patients (76%) with ASK were tertiary referrals. The incidence of the disease in greater London was 0.13 per million, and the incidence in this population of patients with AK was 33 of 178 (18.5%). Mild scleritis/limbitis responsive to topical steroids and oral NSAIDs was present in 11 of 36 eyes (31%), and moderate/severe scleritis, requiring systemic immunosuppressive therapy, was present in 25 eyes (69%). Before the initiation of ASK treatment, 2 of 36 eyes (6%) had corrected distance visual acuity (CDVA) ≥ 20/40. The length of ASK treatment was 15.3 ± 20.7 months. The follow-up after discontinuation of scleritis treatment was 27.2 ± 31.8 months. An improvement in visual acuity was recorded in 23 of 36 eyes (64%). At the final visit, 13 of 36 eyes (36%) had CDVA ≥ 20/40. Control of scleral inflammation and pain was achieved in all but 2 eyes (2 enucleations). Cataract developed in 10 of 36 eyes (28%), and 14 of 36 eyes (39%) developed a persistent epithelial defect. Keratoplasty was performed in 21 of 36 eyes (58%), 9 therapeutic/tectonic and 12 for visual rehabilitation. Six eyes had more than 1 keratoplasty. The mild scleritis group had better outcomes in terms of visual improvement and need for keratoplasty.
  
  
  CONCLUSIONS
  Acanthamoeba sclerokeratitis is associated with poor clinical outcomes. Management of ASK with anti-inflammatory/immunosuppressive treatment is usually effective in reducing both scleral inflammation and symptoms and possibly reduces the number of enucleations.
authors.affiliation: Moorfields Eye Hospital NHS Foundation Trust, London, England; Department of Ophthalmology, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy. Electronic address: alfonsoiovieno@hotmail.com.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Iovieno
authors.affiliation: Moorfields Eye Hospital NHS Foundation Trust, London, England.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Gore
authors.affiliation: Moorfields Eye Hospital NHS Foundation Trust, London, England.
authors.forename: Nicole
authors.initials: N
authors.lastname: Carnt
authors.affiliation: Moorfields Eye Hospital NHS Foundation Trust, London, England; National Institute of Health Research Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and University College of London Institute of Ophthalmology, London, England.
authors.forename: John K
authors.initials: JK
authors.lastname: Dart
mesh_terms: D015823:Acanthamoeba Keratitis / Q000453:epidemiology / Q000628:therapy*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000935:Antifungal Agents / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D015948:Keratoplasty, Penetrating; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D013256:Steroids / Q000627:therapeutic use; D006113:United Kingdom / Q000453:epidemiology; D014792:Visual Acuity; D055815:Young Adult
chemical_list: D000935:Antifungal Agents; D005938:Glucocorticoids; D007166:Immunosuppressive Agents; D013256:Steroids