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[Occupational eczema with photosensitivity caused by contact with Bryozoa]
Abstract:
Contact eczema to Bryozoa is a very invalidating fishermen's disease. Described in the North Sea ("Dogger Bank itch") and in the eastern Channel, it begins with the hands which have touched Bryozoa, these being microscopic "moss-like animals", unrelated to algae, which form coralliform, encrusting and filamentous colonies attached to the sea-floor. Sensitization results from handling nets (drag-nets and trammels) or, less frequently, fish trays. Bryozoa responsible for the disease are Alcyonidum hirsutum and, mostly, Alcyonidum gelatinosum. The case of occupational eczema presented here discloses two hitherto unrecognized allergens: another Bryozoa species, Electra pilosa, which proliferates in the early summer and forms encrusting colonies on various supports, and a sea-weed, Sargassum muticum, which up to now had not been held responsible for skin lesions. The summer outbreaks, from May to September, and the fact that the face and upper chest are involved are classically ascribed to the natural cycle of Bryozoa (colonies multiply in the warm season and regress in the winter) and to contact with uncovered parts of the body. The results of our photobiological exploration suggest that the distribution of the eczema might well be due to an additional photoallergic reaction.