Clinical effectiveness of hymenoptera venom immunotherapy

Treatment failure during venom immunotherapy (VIT) may be
associated with a variety of risk factors. Our aim was to evaluate
the association of baseline serum tryptase concentration (BTC) and
of other parameters with the frequency of VIT failure during the
maintenance phase. In this observational prospective multicenter
study, we followed 357 patients with established honey bee or
vespid venom allergy after the maintenance dose of VIT had been
reached. In all patients, VIT effectiveness was either verified by
sting challenge (n = 154) or patient self-reporting of the outcome
of a field sting (n = 203). Data were collected on BTC, age,
gender, preventive use of anti-allergic drugs (oral antihistamines
and/or corticosteroids) right after a field sting, venom dose,
antihypertensive medication, type of venom, side effects during
VIT, severity of index sting reaction preceding VIT, and duration
of VIT. Relative rates were calculated with generalized additive
models. 22 patients (6.2%) developed generalized symptoms during
sting challenge or after a field sting. A strong association
between the frequency of VIT failure and BTC could be excluded. Due
to wide confidence bands, however, weaker effects (odds ratios