title: Epidemiology of allergic conjunctivitis.
abstract: OBJECTIVE
  To describe currently available epidemiological data on the prevalence of allergic conjunctivitis. Allergic conjunctivitis is often underdiagnosed and consequently undertreated except when it is severe and the chief complaint of a consultation in a specialty clinic. Use of healthcare resources and reduced quality of life of affected individuals justify studies on the prevalence of allergic conjunctivitis.
  
  
  RESULTS
  The association of allergic nasal and ocular symptoms (rhinoconjunctivitis) is common. Most children with allergic conjunctivitis have allergic rhinitis. Older population studies estimate a prevalence of 15-20% of allergic conjunctivitis, but more recent studies implicate rates as high as 40%. Ocular symptoms are common and contribute to the burden of allergic rhinitis and lower quality of life. Ocular allergies rank a very close second and at times may overcome the primary complaints of nasal congestion in rhinoconjunctivitis patients.
  
  
  CONCLUSIONS
  Little focus has been set on the impact of allergic conjunctivitis as comorbidity to asthma and rhinitis in atopic patients. Conjunctivitis symptoms are at least as severe as rhinitis symptoms in patients with 'hay fever' and some have even generated the term of conjunctivorhinitis stressing the ocular symptoms. Prevalence studies should be specifically addressed to ocular allergy symptoms.
authors.affiliation: Pediatric Allergy and Immunology Division, Hospital de Clinicas, Federal University of Parana, Curitiba, Brazil. nelson.rosario@ufpr.br
authors.forename: Nelson
authors.initials: N
authors.lastname: Rosario
authors.forename: Leonard
authors.initials: L
authors.lastname: Bielory
mesh_terms: D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D002648:Child; D015897:Comorbidity; D003233:Conjunctivitis, Allergic / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D003937:Diagnosis, Differential; D005123:Eye / Q000473:pathology*; D006801:Humans; D010256:Paranasal Sinuses / Q000473:pathology*; D015995:Prevalence; D006255:Rhinitis, Allergic, Seasonal / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology