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.