Detection of chromium allergy by cellular in vitro methods

Abstract

Background The standard assay for the detection of chromium sensitization, the patch test, does not allow discrimination between patients with and without clinical symptoms of allergy. Objective The aim of this study was to prove whether cellular in vitro tests are predictive of chromium allergy. Methods Chromium‐sensitized volunteers with and without clinically manifest allergy and non‐sensitized healthy controls (n=37, 19, and 26, respectively) were analysed by cellular in vitro methods using tri‐ and hexavalent chromium (chromium chloride and potassium dichromate) as stimuli. The results were correlated with clinical and anamnestic data. Results Sensitized individuals with an allergy displayed significantly higher lymphocyte transformation test (LTT) responses than sensitized volunteers without allergy and controls (PPP=0.004; sensitization with allergy vs. controls: OR=11.5, Pr=0.49, P=0.002). By IFN‐γ ELISpot, the average precursor cell frequency reactive to trivalent chromium could be defined as 26, 15, and 11 : 10⁶ in volunteers with sensitization and allergy, with sensitization without allergy, and controls, respectively. Conclusions In contrast to the patch test, the LTT appears to be a method that is predictive of chromium allergy.