title: Some immunological aspects of patients with rhinitis in Lebanon.
abstract: BACKGROUND
  Hitherto immunological determinates in Lebanese patients with rhinitis have not been investigated.
  
  
  OBJECTIVE
  To identify causative allergens in Lebanese patients with allergic rhinitis and determine possible correlation's among serum allergen specific antibody, polyclonal IgE, IL-4, IL-5 and peripheral eosinophil levels.
  
  
  METHODS
  One hundred and thirteen patients with a long lasting history of nasal obstruction, rhinorrhea, sneezing and nasal itching were investigated. Serum allergen specific antibodies using a panel of 10 potential allergens, IL-4 and IL-5 levels were determined by enzyme immunoassays. Polyclonal IgE levels were estimated by an immunochromatographic assay and eosinophil counts by a Coulter STKS counter.
  
  
  RESULTS
  Based on the presence of serum allergen-specific IgE antibodies, 74 patients were considered to have an allergic etiology. Polyclonal IgE levels were elevated in 41 of the 74 allergic rhinitis patients while the other 33 patients had normal serum levels. In the remaining 39 specific IgE antibody-negative patients, 32 had normal, and 7 had elevated, polyclonal IgE levels. IgE specific antibodies to more than one allergen were detected in 59 of 74 patients. The most common causative allergens were mite, Dermatophagoides pteronyssinus, Dpt (83.8%) and Dermatophagoides farinae, Df (78.4%). Analysis of the data indicated that elevated polyclonal IgE levels correlated with the concentration of serum specific IgE antibodies and the number of the detected causative allergens per patient. Fifty-nine of 74 allergic rhinitis patients had elevated IL-4 levels and 44 had elevated IL-5 levels. The number of allergic patients with both elevated IL-4 and IL-5 levels was 24. Finally, only 9 allergic rhinitis patients had peripheral eosinophilia.
  
  
  CONCLUSIONS
  Mite Dpt and Df were the most common causative agents of allergic rhinitis in the Lebanese group studied. A prerequisite for Specific Immunotherapy is the identification of the causative allergen. Determinations of polyclonal IgE level and peripheral eosinophil count alone, as an aid to diagnosis are insufficient and may be misleading. On the other hand, determination of all the parameters studied in conjunction appears to be of diagnostic value.
authors.affiliation: Department of Microbiology/Immunlogy, Faculty of Medicine, American University of Beirut, Lebanon. aanoor@aub.edu.lb
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Abdelnoor
authors.forename: Firas
authors.initials: F
authors.lastname: Kobeissy
authors.forename: Daad
authors.initials: D
authors.lastname: Farhat
authors.forename: Usama
authors.initials: U
authors.lastname: Hadi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000485:Allergens; D000818:Animals; D000918:Antibody Specificity; D002648:Child; D004804:Eosinophils; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D015848:Interleukin-5 / Q000097:blood; D007861:Lebanon; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D008925:Mites / Q000276:immunology; D012220:Rhinitis / Q000276:immunology*
chemical_list: D000485:Allergens; D015848:Interleukin-5; D015847:Interleukin-4; D007073:Immunoglobulin E