Long-term protection after stopping venom immunotherapy: Results of re-stings in 200 patients

• Published in: Journal of allergy and clinical immunology 1998-05, Vol.101 (5), p.606-612
• Main Authors: Lerch, Erika, Müller, Ulrich R.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Allergens - immunology; Allergic diseases; Bee Venoms - immunology; Biological and medical sciences; Bites and Stings - immunology; Female; honeybee venom; Humans; Hymenoptera venom allergy; Hypersensitivity, Immediate - diagnosis; Hypersensitivity, Immediate - immunology; Hypersensitivity, Immediate - prevention & control; Hypersensitivity, Immediate - therapy; Immunopathology; Immunotherapy; long-term protection; Male; Medical sciences; Middle Aged; Predictive Value of Tests; Skin allergic diseases. Stinging insect allergies; Time Factors; venom immunotherapy; Vespula venom; Wasp Venoms - immunology
• ISSN: 0091-6749; 1097-6825
• DOI: 10.1016/S0091-6749(98)70167-8

Background: Venom immunotherapy (VIT) protects most patients allergic to Hymenoptera stings while booster injections are continued. Few data on long-term protection after discontinuation of treatment are available. Objective: We sought to investigate protection from re-stings over a prolonged period after stopping VIT. Methods: Re-sting data were obtained from 200 of 322 patients in whom VIT had been stopped between 1988 and 1992 after a duration of at least 3 years. The 25 (12.5%) patients who again developed systemic allergic reactions were compared with 50 matched patients without re-sting reactions. Clinical data and diagnostic parameters (i.e., skin sensitivity and specific IgE and IgG) were studied. Results: Of the 25 patients who had re-sting reactions, 19 had been treated with bee venom (relapse rate, 15.8%), and six had been treated with Vespula venom (relapse rate, 7.5%). About half of the re-sting reactions occurred on the first re-sting after stopping VIT. Most of these reactions were mild, whereas the majority of reactions occurring after repeated re-stings were severe. When re-sting reactions were related to the total re-stings per year, an accumulation of sting reactions was observed in years 3 to 5 after stopping VIT. Patients with re-sting reactions had been receiving VIT for a significantly shorter duration (43.35 months) than those with continued protection (54.65 months) ( p < 0.01). Of the diagnostic parameters, only a negative intracutaneous skin test at 10 -3 gm/L predicted long-term protection reliably. Conclusion: Venom immunotherapy of 3 to 5 years duration induces long-term protection in most patients. In rare occasions severe re-sting reactions may, however, occur, especially after repeated re-stings. (J Allergy Clin Immunol 1998;101:606-12.)