Immediate-type hypersensitivity reactions to proton pump inhibitors: usefulness of skin tests in the diagnosis and assessment of cross-reactivity
Prof. Sevim Bavbek, Department of Pulmonary Diseases, Division of Allergy and Clinical Immunology, Ankara University, School of Medicine, 06100, Ankara, Turkey.
Data are limited about the value of skin tests in the diagnosis of proton pump inhibitor (PPI)-induced hypersensitivity reactions and the cross-reactivity between PPIs. We aimed to assess the role of skin testing in the diagnosis of PPI-related immediate hypersensitivity reactions and the cross-reactivity patterns among PPIs.
The study was designed in a prospective, national, multicentre nature. Sixty-five patients with a suggestive history of a PPI-induced immediate hypersensitivity reaction and 30 control subjects were included. Standardized skin prick and intradermal tests were carried out with a panel of PPIs. Single-blind, placebo-controlled oral provocation tests (OPTs) with the PPIs other than the culprit PPI that displayed negative results in skin tests (n = 61) and diagnostic OPTs with the suspected PPI (n = 12) were performed.
The suspected PPIs were lansoprazole (n = 52), esomeprazole (n = 11), pantoprazole (n = 9), rabeprazole (n = 2), and omeprazole (n = 1). The sensitivity, specificity, and negative and positive predictive values of the skin tests with PPIs were 58.8%, 100%, 70.8%, and 100%, respectively. Fifteen of the 31 patients with a hypersensitivity reaction to lansoprazole had a positive OPT or skin test result with at least one of the alternative PPIs (8/52 pantoprazole, 6/52 omeprazole, 5/52 esomeprazole, 3/52 rabeprazole).
Considering the high specificity, skin testing seems to be a useful method for the diagnosis of immediate-type hypersensitivity reactions to PPIs and for the evaluation of cross-reactivity among PPIs. However, OPT should be performed in case of negativity on skin tests.