Use of Intradermal Dilutional Testing and Skin Prick Testing: Clinical Relevance and Cost Efficiency

Abstract

Antigens which show reactivity to a multiple SPT device usually have a treatable endpoint that is independent of the degree of positivity of the SPT result. IDT is an important step in the determination of the strongest starting dose of immunotherapy that may be safely administered. Initiating immunotherapy in this manner may potentially create significant health care savings by shortening the time required for a patient to reach their individual maximally tolerated dose. The use of a relatively large screening panel is cost effective and does not increase the average number of antigens treated by immunotherapy. Blended allergy testing techniques that include IDT in their protocol are comparable in cost with commonly used allergy testing protocols.

Comparative effectiveness of allergy testing method in driving immunotherapy outcomes

“…Our result is contradictory to a prior study which suggested that SPT screening with follow‐up IDT testing would result in faster escalation and cost savings compared to SPT alone . An ideal allergy test would benefit the patient and the healthcare system by decreasing the time to maintenance AIT.…”

“…An ideal allergy test would benefit the patient and the healthcare system by decreasing the time to maintenance AIT. In a prior study that used 2004 Medicare rates the authors calculated that shortening the course of immunotherapy saves the system at least $1062 per patient per year . Shah and Emanuel compared the cost (using hospital cost data) of 2 groups: (1) SET via IDT for 14 allergens to (2) SPT screening followed by SET of only positive allergens.…”

“…A cost‐benefit analysis was to be performed if the IDT group had decreased days to maintenance compared to the SPT group (positive ICER). The additional number of immunotherapy sessions for the SPT group would be converted to US$ based on 2013 Medicare reimbursement data for immunotherapy sessions . If the IDT group had increased days to maintenance compared to the SPT group (negative ICER), a modified sensitivity analysis was planned to determine difference in days to achieve indifference (breakeven threshold) between the 2 strategies.…”

High volume of polysorbate‐containing (Tween® 80) solutions induces false‐positive results in intradermal test

“…Intradermal test is a well‐established diagnostic tool for immediate‐type allergies and is used by allergologists as an additional cutaneous test besides skin prick testing . It allows cost‐effective, immediate interpretation of test results compared to serum measurements of specific IgE levels . For exact interpretation of results, standardized allergen extract concentrations, dilutions, added substances and standardized techniques are essential .…”

“…[27][28][29] It allows cost-effective, immediate interpretation of test results compared to serum measurements of specific IgE levels. 30,31 For exact interpretation of results, standardized allergen extract concentrations, dilutions, added substances and standardized techniques are essential. 2,8,32 Phenol is widely used as a preservative and has shown to have no effect on mast cell degranulation at the used concentrations.…”