Safety of subcutaneous specific immunotherapy with pollen allergen extracts for respiratory allergy.
BACKGROUND
Specific immunotherapy (SIT) is a well-documented treatment for respiratory allergy. However, the major risk of SIT is the development of systemic anaphylactic reactions.


OBJECTIVE
To evaluate the safety of SIT given by subcutaneous route for 3 years to patients with seasonal allergic rhinitis (AR) with or without asthma.


METHODS
A prospective open-label study of immunotherapy (Chenopodium album, Bermuda grass, or both) in 181 consecutive patients with AR with or without asthma. After an initial dose-escalation phase, a maintenance dose of 0.5 ml of 100,000 PNU/ml was administered monthly for 3 years. The occurrence and severity of systemic reaction (SR) and local reaction was recorded and graded according to the WHO position paper.


RESULTS
Of 181 patients enrolled, 57 (31%) did not complete the study (53 due to poor compliance and 4 due to systemic side effects). All 4 patients who developed SR had asthma and all the SR occurred during the dose- escalation phase. Three patients had moderate SR (grade 2), while 1 patient had severe reaction (grade 3). Three of the SR occurred within the first 20 min after injection and 1 SR occurred 2 h after injection. None of the reactions were life threatening and were managed easily. Total rhinitis symptom score decreased from 11.8 at baseline to 7.46 at the end of treatment (p<0.001). The size of the skin prick test reaction to the main sensitising allergen was reduced from 7.48 +/- 2.26 mm at baseline to 5.60 +/- 2.18 mm at the end of treatment, p<001.


CONCLUSIONS
If a strict protocol is used, SIT is safe in AR patients with or without mild asthma and may result in significant subjective and objective improvement.
Arifhodzic
N
N
Al Rashed Allergy Centre, Kuwait University, Safat, Kuwait.
Behbehani
N
N
Duwaisan
A R
AR
Al-Mosawi
M
M
Khan
M
M
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000628:therapy*; D003888:Desensitization, Immunologic / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D007279:Injections, Subcutaneous; D008297:Male; D011058:Pollen / Q000276:immunology*; D011446:Prospective Studies; D006255:Rhinitis, Allergic, Seasonal / Q000628:therapy*