Persistent post-occupational dermatitis: report of five cases.

Persistent post-occupational dermatitis is a phenomenon that is well-recognized by occupational dermatologists, but there have been few studies on it. In view of this, we proposed to assess the prevalence of this phenomenon in an English setting and ascertain the characteristics of the patients affected. Using modified criteria adapted from previous studies, details of 1100 patients seen in a contact dermatitis clinic were screened. Persistent post-occupational dermatitis was diagnosed in 5 patients out of 1100 seen over a 35-month period in a contact clinic (4 women, 1 man; age of onset 19-52 years). All had hand dermatitis that persisted despite removal of the apparent causative agents. Four patients were nickel-allergic on patch testing, though nickel was thought to be a potential causative agent in only one case and 2 patients were allergic to thiuram-mix on patch testing, and in both thiuram had a possible causative role. In all 5 cases, irritant exposure seemed important, with allergic factors contributing in 3 cases. Two patients had had eczema in childhood. Persistent post-occupational dermatitis is uncommon, affecting less than 0.5% of patients seen in a contact dermatitis clinic, but when diagnosed it has major implications for the future employment prospects of the individuals concerned.