title: Retinitis pigmentosa in Puerto Rico.
abstract: BACKGROUND
  Previous studies have reported that the prevalence of retinitis pigmentosa (RP) varies between one per 3,000 to one in per 5,000 in the general population.
  
  
  OBJECTIVE
  To study the incidence and ocular findings of RP in a sub-urban community in Puerto Rico.
  
  
  METHODS
  We conducted a non-concurrent prospective study of 10,100 patients in a sub-urban San Juan community.
  
  
  RESULTS
  44 out of the 10,100 patients had RP (0.44%). Eight out of the 44 patients (18%) had nystagmus, twenty-eight (31.8%) had microcornea, 3 patients (6.8%) had sluggish papillary reaction. Six patients (13.6%) had mild cataracts, 27 (65.9%)had attenuated retinal vessels and thirty five patients (81.4%) had bony spicules. Fifteen patients (34.1%) out of the 44 had retinitis pigmentosa as part of the Bardet-Biedl syndrome.
  
  
  CONCLUSIONS
  Incidence of RP in Puerto Rico is higher when compared to Maine and Spain (p < 0.001). Autosomal recessive pattern of inheritance is the most common in Puerto Rico. These findings could be due to the island's geographic isolation, and inbreeding.
authors.affiliation: Department of Ophthalmology, University of Puerto Rico, Medical Sciences Campus.
authors.forename: Horacio M
authors.initials: HM
authors.lastname: Tous
authors.forename: Natalio J
authors.initials: NJ
authors.lastname: Izquierdo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011647:Puerto Rico / Q000453:epidemiology; D012174:Retinitis Pigmentosa / Q000453:epidemiology*; D018881:Suburban Health