Comparison of the efficacy of subcutaneous and sublingual immunotherapy in mite-sensitive patients with rhinitis and asthma--a placebo controlled study.
BACKGROUND
The efficacy of therapy with sublingual allergen extracts is unproven.


OBJECTIVE
To evaluate the clinical and immunologic outcome of sublingual immunotherapy and to compare the results with subcutaneous immunotherapy and placebo in 36 patients with rhinitis and asthma due to mite allergy.


METHODS
Thirty-six patients with rhinitis and asthma due to mite allergy were randomly divided into three groups in order to receive subcutaneous injections with allergenic extracts, sublingual drops with solutions of purified standardized allergen preparations, or sublingual placebo for a period of 1 year. Assessment of clinical and immunologic efficacy included symptom and medication scores, methacholine provocation tests, skin prick tests, and specific IgE and IgG4 antibody concentrations.


RESULTS
Subcutaneous immunotherapy for both rhinitis and asthma was clinically effective. Patients treated with sublingual immunotherapy had decreased rhinitis symptoms (P < .01) but no change in asthma scores. Medication scores significantly decreased in both actively treated groups (P < .01) at the first year compared with baseline. When skin prick tests were evaluated, the subcutaneously treated group had a significant decrease in the wheal diameter of D. pteronyssinus (P < .01), D. farinae (P < .05), and histamine (P < .05) while other two groups showed no difference. There was no significant change in methacholine PC20 values in all groups at the end of the first year when compared with baseline. No change in D. pteronyssinus and D. farinae specific IgE levels were observed; however, specific IgG4 concentrations were significantly higher than baseline both in sublingual and subcutaneous immunotherapy groups (P < .05) after 1 year immunotherapy. No significant difference was obtained in any of these parameters in the placebo group.


CONCLUSIONS
Sublingual immunotherapy may be effective in patients with allergic rhinitis. Further, we believe it is a potential therapy for allergic asthmatic patients. The clinical usefulness of this form of immunotherapy (when administered to larger study groups for a longer time) and the mechanisms underlying its immunologic effect deserve additional studies.
Mungan
D
D
Department of Allergic Diseases, Faculty of Medicine, Ankara University, Turkey.
Misirligil
Z
Z
Gürbüz
L
L
D000279:Administration, Cutaneous; D000286:Administration, Sublingual; D000293:Adolescent; D000328:Adult; D000818:Animals; D001249:Asthma / Q000276:immunology*; D001985:Bronchial Provocation Tests; D000939:Epitopes; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000150:complications; D007114:Immunization; D007073:Immunoglobulin E / Q000276:immunology; D007167:Immunotherapy; D008297:Male; D008875:Middle Aged; D008925:Mites / Q000276:immunology*; D012220:Rhinitis / Q000276:immunology*
D000939:Epitopes; D007073:Immunoglobulin E