Comparison of results of immunotherapy based on skin end-point titration, prick testing, and scratch testing

Presented is a clinical study comparing the result of immunotherapy based on allergy testing with three different test modalities: skin end-point titration, prick testing, and scratch testing. Thirty patients with allergic rhinitis were randomly assigned to one of the three test groups. Treatment vials were made on test results according to the instructions for each test. For skin end-point titration, each antigen was included at a concentration based on the patient's sensitivity, found with the fivefold dilution testing procedure. For the prick test, treatment vials were based on a two-level test response scale of stronger or lesser positive results. The scratch test yields vials used in one concentration based simply on a positive vs. negative test result. Patients in all three groups were treated at weekly intervals with immunotherapy, progressing in volume until the maximum tolerated dose was achieved. Relief of symptoms was evaluated after 6 months of treatment. Nine of the 10 patients receiving skin end-point titration based immunotherapy had complete relief of symptoms, and one had partial relief. None of the patients in the prick or scratch test groups achieved relief of symptoms after 6 months of treatment. Results dramatically demonstrate the need to base allergy immunotherapy treatment on a test that quantifies the patient's level of sensitivity to each antigen.