Epidemiological, clinical and allergological observations on pompholyx.

We have studied a group of 104 patients with pompholyx, to investigate the relationship between allergological factors and its etiopathogenesis. The following examinations were performed: blood sampling (routine tests and IgE levels), allergological tests (patch, prick, intradermal, and oral provovation tests with nickel sulphate), skin biopsy to exclude pemphigus vulgaris or bullous pemphigoid. An accurate history of familial and personal allergic diathesis was enquired for and various possible aggravating factors (season, microclimate, perspiration and emotional stress) were considered. The results were age and sex-matched with a healthy control group (208 subjects). We found familial and personal atopic diathesis in 50% of patients versus 11.5% of controls (p less than 0.001); 39 patients (37.49%) also had high levels of IgE. Nickel sulphate was the allergen with the highest positivity on patch testing: 20.19% versus 6.25% of the control group (p less than 0.001). The % of patients allergic to nickel reached 26%, including those (6 patients) reacting to the oral provocation test. Season (43 patients) and hyperhidrosis (38) were the aggravating factors most commonly claimed. We detected no correlation between age, sex, grading of pompholyx and the allergological parameters investigated. Though several different allergological findings have previously been reported in dyshidrosis, their role in its pathogenesis has not yet been fully explained. We think that different haptens or antigens can produce the same clinical and histological picture of pompholyx in predisposed subjects.