Pustulosis palmoplantaris and chronic eczematous hand dermatitis. Treatment, epidermal Langerhans cells and association with thyroid disease.

Long-standing hand and foot dermatoses, e.g. pustulosis palmoplantaris (PPP) and chronic eczematous hand dermatitis, severely affect the patients' quality of life. The cause of PPP is unknown and the disease usually responds unsatisfactorily to treatment. The aims of the studies of PPP were to determine the prevalence of thyroid disease and to evaluate the relative merits of treatment with etretinate, psoralen photochemotherapy (PUVA), and a combination of the two. Furthermore, epidermal Langerhans cells (LC) were quantified in lesional skin before and after treatment. The prevalence of thyroid disease was significantly increased in a group of PPP patients compared to normal individuals and psoriasis patients. Both hypo and hyperthyroidism were found. In addition, circulating autoantibodies to thyroid antigens were more common in patients with PPP than in the control group. The thyroid status was further examined in a new and larger group of PPP patients, including a 4-year follow-up examination of those with thyroid antibodies or subclinical thyroid dysfunction. The increased prevalence of thyroid diseases was corroborated when this PPP group was compared to an age and sex-matched control population sample from the same city. Some patients also showed biochemical evidence of gastric autoimmunity. Ninetyfour percent of the PPP patients were smokers at the time of onset of the skin disease, compared to 33% of the subjects in a control group. Patients with treatment-resistant PPP were recruited for a randomised, double-blind and placebo-controlled trial. A combination of etretinate and PUVA was more effective than monotherapy with etretinate or PUVA. The latter were equally effective. Etretinate frequently provoked side effects. Follow-up examinations showed a high relapse rate. Epidermal LC were visualised with monoclonal antibodies to Leu 6 and HLA-DR antigens utilizing an immunoperoxidase technique. Their number was increased in lesional skin. The number of HLA-DR positive LC was decreased following etretinate, and normalised with etretinate + PUVA. Chronic eczematous hand dermatitis is a common clinical challenge. These studies aimed at an evaluation of PUVA and UVB phototherapy in patients with recalcitrant lesions and to enumerate epidermal LC before and after treatment. PUVA was a highly effective mode of treatment and cleared all treated hands. UVB was better than no treatment but the dermatitis did not clear in any patient. The number of epidermal LC was increased in lesional palmar skin in both allergic contact dermatitis, irritant contact dermatitis and hyperkeratotic dermatitis of the palms.(ABSTRACT TRUNCATED AT 400 WORDS)