To the Editor.— I read with interest the communication by Halevy et al (241:2144, 1979) wherein reference was made to our work and that of others relative to the effect of dialysis on psoriasis. 1,2 The authors' notation that improvement occurs in most or at least some patients receiving dialysis therapy, that there are relatively few if any notable harmful side effects, and that there may be fluctuations in the degree of response (especially associated with stressful events) all appear to be important. Whether the "psychosomatic effect of the invasive procedure may be a major factor" remains in the area of conjecture, however. Our experience and communication with others throughout the world would confirm the authors' impressions. We would add that peritoneal dialysis appears to have the edge on hemodialysis, although there have been long-standing remissions both after hemodialysis and even after a cardiopulmonary bypass oxygenation procedure associated with a