Nickel allergy: relationship between patch test and repeated open application test thresholds

Abstract

For elicitation of nickel allergy the elicitation threshold for the patch test is higher than the elicitation threshold (per application) for the ROAT, but is approximately the same as the accumulated elicitation threshold for the ROAT. This may be important for risk assessment based on dose-response results from allergic patients.

Clinical Utilization of Repeated Open Application Test Among American Contact Dermatitis Society Members

“…However, nickel may elicit a reaction within 1 week. 19 Therefore, the ideal length of ROAT likely depends on the allergen in question.…”

New UK nickel‐plated steel coins constitute an increased allergy and eczema risk

“…The amount of nickel on the skin needed for elicitation of hand eczema varies between individuals. Open application on the skin with concentrations as low as 0.035 μg nickel/cm 2 twice daily for 1 week can give rise to eczema in 20% of nickel-allergic individuals (21). The open application of low doses of nickel is of great relevance for comparison with nickel exposure from coin handling and from other items.…”

A Practical Guide to Patch Testing

“…Although the threshold concentration for a positive reaction for the ROAT per application was significantly lower than the threshold concentration for a positive PT, the accumulated ROAT dose was very similar to the PT. 29 A Usage Test can also be performed with the daily direct application of the undiluted product on the skin to which the product is normally applied, under real world conditions. Summary 1.…”