title: Utility of red amsler grid screening in a rheumatology clinic.
abstract: OBJECTIVE
  To ascertain the false positive rate of red Amsler grid screening in an outpatient rheumatologic setting.
  
  
  METHODS
  Red Amsler grid screening was performed on 170 consecutive patients presenting with rheumatoid arthritis or systemic lupus erythematosus. Patients with abnormal screening results were referred for ophthalmologic evaluation and formal visual field testing.
  
  
  RESULTS
  Nineteen patients identified scotomata on red Amsler grid. Despite numerous recall attempts, only 9 of the 19 patients with scotomata presented for ophthalmologic evaluation. The positive predictive value was 5-58%. Roughly 6-11% of all patients screened had a false positive screening test.
  
  
  CONCLUSIONS
  While red Amsler grid screening may allow rheumatologists to identify patients who are more likely to have hydroxychloroquine ocular toxicity, an abnormal red Amsler grid screening is in itself an unreliable predictor of toxicity.
authors.affiliation: Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
authors.forename: Anne C
authors.initials: AC
authors.lastname: Pluenneke
authors.forename: Preston H
authors.initials: PH
authors.lastname: Blomquist
mesh_terms: D018501:Antirheumatic Agents / Q000009:adverse effects*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D006886:Hydroxychloroquine / Q000009:adverse effects*; D008180:Lupus Erythematosus, Systemic / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012607:Scotoma / Q000139:chemically induced* / Q000175:diagnosis; D015351:Vision Screening / Q000379:methods* / Q000592:standards
chemical_list: D018501:Antirheumatic Agents; D006886:Hydroxychloroquine