title: Herpes simplex keratitis misdiagnosed as rheumatoid arthritis-related peripheral ulcerative keratitis.
abstract: OBJECTIVE
  To report 2 cases of herpes simplex keratitis misdiagnosed as rheumatoid arthritis (RA)-related peripheral ulcerative keratitis (PUK), where isolation of the herpes simplex virus (HSV) led to a complete modification in management.
  
  
  METHODS
  This is a case report.
  
  
  RESULTS
  Two patients with RA presented with painful red right eyes. Ocular examination in both revealed an ulcer involving the peripheral cornea. The adjacent conjunctiva was infected, and the underlying sclera appeared inflamed. A diagnosis of corneal PUK secondary to RA was therefore made. The first patient had corneal scrapes taken for routine microbiological examination, which included polymerase chain reaction (PCR) for HSV. In the second patient, despite systemic immunosuppressive therapy, the ulcer progressed to involve deeper stroma and more central cornea. The conjunctiva adjacent to the ulcer was resected, and healthy conjunctival tissue was mobilized to cover the peripheral corneal ulcer. Resected conjunctival and corneal tissue was histopathologically assessed. In the first patient, PCR for HSV yielded a positive result. This prompted treatment with immediate systemic and topical acyclovir. The ulcer responded well to treatment. In the second patient, histopathological assessment and electron microscopy identified HSV. Treatment with topical trifluorothymidine and steroids was started, and a good recovery was made.
  
  
  CONCLUSIONS
  Treatment of PUK is with systemic immunosuppressive therapy, and such therapies have serious side effects. PUK may have an occult cause in RA, and a search for a secondary agent may be beneficial. In particular, occult HSV infection must be ruled out before commencing immunosuppressive therapy.
authors.affiliation: Department of Ophthalmology, Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, UK. sarah_zaher@hotmail.com
authors.forename: Sarah S
authors.initials: SS
authors.lastname: Zaher
authors.forename: Teresa
authors.initials: T
authors.lastname: Sandinha
authors.forename: Fiona
authors.initials: F
authors.lastname: Roberts
authors.forename: Kanna
authors.initials: K
authors.lastname: Ramaesh
mesh_terms: D000212:Acyclovir / Q000627:therapeutic use; D000368:Aged; D000998:Antiviral Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000150:complications*; D003315:Cornea / Q000648:ultrastructure / Q000821:virology; D003320:Corneal Ulcer / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D005500:Follow-Up Studies; D018259:Herpesvirus 1, Human / Q000235:genetics; D006801:Humans; D016849:Keratitis, Herpetic / Q000175:diagnosis* / Q000188:drug therapy / Q000821:virology; D008297:Male; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D012367:RNA, Viral / Q000032:analysis; D014271:Trifluridine / Q000627:therapeutic use
chemical_list: D000998:Antiviral Agents; D012367:RNA, Viral; D014271:Trifluridine; D000212:Acyclovir