Clinical trial NCT02503800: The Significance of Blood-tryptase and c-Kit Mutation in Insect Venom Immunotherapy
Official title: The Significance of Blood-tryptase Levels and c-Kit Mutation in the Evaluation of Prognosis and Adverse Reactions in Subjects Undergoing Venom Immunotherapy for Insect Allergy
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Hypersensitivity, Immediate
Insect Bites and Stings
Mastocytosis
Lead sponsor: Meir Medical Center
Sponsor class: OTHER
First posted: 2015-07-21
Enrollment: 159
Sex: ALL
Minimum age (years): 4
Maximum age (years): 75
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: The population will include all the subjects undergoing venom immunotherapy at the Clinic of Allergy and Clinical Immunology, Meir Medical Center.

Brief summary: The investigators wish to evaluate the association between tryptase values as well as c-Kit mutation and adverse effects in the course of immunotherapy. The investigators also intend to assess the effect of immunotherapy on tryptase levels.

Detailed description: According to the presently available reports there is an association between systemic allergic responses to hymenoptera venom and elevated tryptase levels or c-Kit mutation. The presence of these findings may imply the existence of mast cell activation syndrome or mastocytosis. Therefore, baseline tryptase evaluation has become standard evaluation in patients with systemic responses. Meir Medical Center is the only hospital in Israel in which tryptase can be measured. Consequently, the Meir Clinic has accumulated considerable data with regards to tryptase levels in subjects with allergy to hymenoptera venom. The investigators wish to evaluate the association between tryptase values as well as c-Kit mutation and adverse effects in the course of immunotherapy. The investigators also intend to assess the effect of immunotherapy on tryptase levels.

Eligibility criteria: Inclusion Criteria:

* history of systemic response to hymenoptera sting.
* subject under current or planned venom immunotherapy.

Exclusion Criteria:

* previously diagnosed mast cell disorder

Primary outcomes:
measure: The association between tryptase values/c-Kit mutation and immunotherapy adverse events will be evaluated using blood sample analysis and patient medical records.
timeFrame: up to 12 months
Secondary outcomes:
measure: The association between tryptase values/c-Kit mutation and severity of index sting event will be evaluated using blood sample analysis and patient medical records.
timeFrame: up to 12 months
Other outcomes:
Locations:
city: Kfar Saba
country: Israel
facility: Meir Medical Center
Study officials:
affiliation: Meir Medical Center
name: Alon Y Hershko, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Cichocka-Jarosz E, Sanak M, Szczeklik A, Brzyski P, Pietrzyk JJ. Impact of Hymenoptera venom allergy and the effects of specific venom immunotherapy on mast cell metabolites in sensitized children. Ann Agric Environ Med. 2014;21(2):294-301. doi: 10.5604/1232-1966.1108594.
citation: Niedoszytko M, de Monchy J, van Doormaal JJ, Jassem E, Oude Elberink JN. Mastocytosis and insect venom allergy: diagnosis, safety and efficacy of venom immunotherapy. Allergy. 2009 Sep;64(9):1237-45. doi: 10.1111/j.1398-9995.2009.02118.x. Epub 2009 Jul 21.
citation: Zanotti R, Lombardo C, Passalacqua G, Caimmi C, Bonifacio M, De Matteis G, Perbellini O, Rossini M, Schena D, Busa M, Marcotulli MC, Bilo MB, Franchini M, Marchi G, Simioni L, Bonadonna P. Clonal mast cell disorders in patients with severe Hymenoptera venom allergy and normal serum tryptase levels. J Allergy Clin Immunol. 2015 Jul;136(1):135-9. doi: 10.1016/j.jaci.2014.11.035. Epub 2015 Jan 17.