title: Pediatric Conjunctivitis and Air Pollution Exposure: A Prospective Observational Study.
abstract: OBJECTIVE
  To investigate, in pediatric patients, the rate and clinical features of unspecific conjunctivitis of unknown origin (UCUO) and to evaluate their relationship with air pollution.
  
  
  METHODS
  From January to December 2013, we consecutively screened all of the patients referred for symptomatic ocular surface inflammation. Inclusion criteria for this study were age<14, diagnosis of conjunctivitis, residence in the Lombardia region. UCUO was defined as conjunctivitis of unknown etiology, not clearly due to infection or allergy. Based on addresses of residence and sites of 73 automatic air pollution monitoring stations (locations and mean annual particulate matter (PM) 10 and 2.5 concentrations were provided by the Regional Environmental Protection Agency (ARPA) Lombardia), each patient was paired with a value of exposure to PM. Relationship between UCUO and PM exposure was investigated.
  
  
  RESULTS
  A total of 132 of 251 screened children were included in this study. UCUO was diagnosed in 48/132 patients. The most common symptoms and signs in UCUO children were foreign body sensation (37/48) and conjunctival hyperemia (45/48), respectively. PM10 exposure value was significantly higher in UCUO (33.5±5.4µg/m3) compared to other groups (P<0.001, ANOVA). UCUO/total conjunctivitis ratio was significantly higher in residents in areas with more than 75 (Q3) days/year exceeding 50µg/m3 (EU legal limit) compared to areas with less than 45 (Q1) exceedances/year: 24/39: 61% vs 8/35: 23%; P>0.001, Chi-square test.
  
  
  CONCLUSIONS
  Our data suggest a relationship between UCUO and air pollution. This form of conjunctivitis is not rare in pediatric patients and may be the most frequent in most polluted areas.
authors.affiliation: a Department of Clinical Sciences and Community Health , University of Milan , Milan , Italy.|b Eye Clinic , San Giuseppe Hospital , Milan , Italy.
authors.forename: Paolo
authors.identifier: http://orcid.org/0000-0002-4036-703X
authors.initials: P
authors.lastname: Nucci
authors.affiliation: a Department of Clinical Sciences and Community Health , University of Milan , Milan , Italy.|b Eye Clinic , San Giuseppe Hospital , Milan , Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Sacchi
authors.affiliation: a Department of Clinical Sciences and Community Health , University of Milan , Milan , Italy.|b Eye Clinic , San Giuseppe Hospital , Milan , Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Pichi
authors.affiliation: c Eye Clinic , Rapallo Hospital , Genova , Italy.
authors.forename: Pia
authors.initials: P
authors.lastname: Allegri
authors.affiliation: a Department of Clinical Sciences and Community Health , University of Milan , Milan , Italy.|b Eye Clinic , San Giuseppe Hospital , Milan , Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Serafino
authors.affiliation: a Department of Clinical Sciences and Community Health , University of Milan , Milan , Italy.|b Eye Clinic , San Giuseppe Hospital , Milan , Italy.
authors.forename: Marika
authors.initials: M
authors.lastname: Dello Strologo
authors.affiliation: d Eye Clinic , Azienda Ospedaliero-Universitaria Maggiore della Carità , Novara , Italy.|e Eye Clinic , San Paolo Hospital , Milan , Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: De Cillà
authors.affiliation: a Department of Clinical Sciences and Community Health , University of Milan , Milan , Italy.|b Eye Clinic , San Giuseppe Hospital , Milan , Italy.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Villani
mesh_terms: D000293:Adolescent; D000397:Air Pollution / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D003231:Conjunctivitis / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007558:Italy / Q000453:epidemiology; D008297:Male; D052638:Particulate Matter / Q000009:adverse effects*; D015995:Prevalence; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D052638:Particulate Matter
keywords: Children; environment; health; ocular surface; particulate matter