Dialysis for psoriasis - preliminary remarks concerning mode of action.

In one patient treated by peritoneal dialysis for psoriasis the skin lesions cleared completely. In two persons hemodialysis gave unsatisfactory results. In treated and another three untreated patients cellular immunity was evidently suppressed. This phenomenon is similar to the immunologic changes in persons with uremia. Solutes in middle molecular weight range (SMMWR) suppress cellular immunity. These compounds were therefore investigated in psoriatics. The level of SMMWR was lower before than after each dialysis, although their concentration increased slightly during the dialytic treatment. This suggests that solutes in middle molecular weight are fixed in the epidermis and/or in the walls of the skin capillaries and that dialysis liberates them from these places. Peritoneal dialysis seems to be a more effective method of treating psoriasis than hemodialysis. Solutes in middle molecular weight range might play an important role in the pathomechanisms of this multifactorial disease.