title: Skin test reactivity and Der p-induced interleukin 10 production in patients with asthma or rhinitis infected with Ascaris.
abstract: BACKGROUND
  Helminth infections have been associated with reduced reactivity to aeroallergens, which could be related to interleukin 10 (IL-10) production, as reported in schistosomiasis.
  
  
  OBJECTIVE
  To compare skin responses to aeroallergens with Der p specific IL-10 production in patients with asthma or rhinitis according to Ascaris infection status.
  
  
  METHODS
  Cross-sectional study of 113 patients with asthma or rhinitis from a region endemic for geohelminths. Stool examinations and skin prick tests to aeroallergens were performed in all the patients. Der p specific IL-10 production was measured in the supernatant of peripheral blood mononuclear cell (PBMC) cultures of a subsample of 53 patients.
  
  
  RESULTS
  Forty-seven patients had Ascaris in their stool samples. Skin test results were positive in 77% of Ascaris-infected patients and in 71% of uninfected individuals. Median levels of Der p specific IL- 10 in PBMC cultures of infected and uninfected patients were similar (7.8 and 8.4 pg/mL, respectively). The lack of association remained when parasite load was taken into account and when patients with evidence of previous infection were removed from the uninfected group.
  
  
  CONCLUSIONS
  In patients with asthma or rhinitis living in an urban area endemic for geohelminths, we found no association between Ascaris infection and skin reactivity to aeroallergens. Furthermore, there was no difference in Der p specific IL-10 production by PBMCs. These negative findings indicate that different from what is observed in Schistosoma infection, Ascaris lumbricoides infection in individuals living in an urban area does not induce strong regulatory responses.
authors.affiliation: Respiratory Disease Center, University Hospital Professor Edgard Santos, Salvador, Brazil. evponte@yahoo.com.br
authors.forename: Eduardo Vieira
authors.initials: EV
authors.lastname: Ponte
authors.forename: Fabiana
authors.initials: F
authors.lastname: Lima
authors.forename: Maria Ilma
authors.initials: MI
authors.lastname: Araújo
authors.forename: Ricardo Riccio
authors.initials: RR
authors.lastname: Oliveira
authors.forename: Luciana Santos
authors.initials: LS
authors.lastname: Cardoso
authors.forename: Alvaro Augusto
authors.initials: AA
authors.lastname: Cruz
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000276:immunology*; D001196:Ascariasis / Q000453:epidemiology / Q000276:immunology*; D017164:Ascaris lumbricoides / Q000276:immunology; D001249:Asthma / Q000276:immunology / Q000382:microbiology*; D003430:Cross-Sectional Studies; D004785:Environmental Pollutants; D005260:Female; D006801:Humans; D016753:Interleukin-10 / Q000276:immunology / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D008297:Male; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology / Q000382:microbiology*; D012882:Skin Tests
chemical_list: D000485:Allergens; D039741:Antigens, Dermatophagoides; D004785:Environmental Pollutants; D016753:Interleukin-10