[Peroral nickel provocation in nondyshidrosiform and dyshidrosiform nickel eczema]

The flare-up of pompholyx-type nickel eczema induced by oral nickel challenge has been dealt with in several publications. To compare the reactivity of non-pompholyx and pompholyx-type nickel eczema, we challenged three groups of female volunteers (7 with non-pompholyx-type and 12 with pompholyx-type nickel eczema plus 10 control subjects without nickel allergy) with an oral dose of 2.5 mg nickel. By patch testing we additionally determined the degree of cutaneous nickel sensitivity using a series of nickel sulfate dilutions (5.0-0.00001%) and an possible cobalt allergy using 1% cobalt chloride. In 8 of the 19 patients with nickel allergy, the oral nickel challenge was positive (rash, flare-up at sites of healed eczema and former nickel patch tests, and worsening of preexisting eczema; acute pompholyx lesions only in patients with pompholyx-type eczema). The positive results showed the same frequency in non-pompholyx eczema (43%) as in the pompholyx type (42%). Moreover, no substantial difference was found in the degree of cutaneous nickel sensitivity between the two groups of eczema, and there was no correlation between these results and the outcome of the oral nickel challenge. An additional cobalt allergy was recorded significantly more often in pompholyx-type eczema (P = 0.048), yet there was no influence on the oral nickel challenge. The laboratory parameters examined (differential white cell count and total IgE) did not differ in either of the two eczema groups and did not change substantially during nickel challenge reactions.