Cryotherapy as a treatment for psoriasis.

There are very few publications on the use of cryotherapy in the treatment of psoriasis. We performed an evaluation to determine its efficacy in small plaque psoriasis. We selected 63 patients who had a clinical diagnosis of chronic plaque-type psoriasis and and for each patient we evaluated two psoriatic plaques of almost the same size and severity on similar areas of the body. One plaque was sprayed with liquid nitrogen every other day for two weeks and the other plaque was untreated as a control. Complete resolution of the plaque occurred in four patients (6.35 %), mild to moderate resolution was evident in 19 cases (30.1 %), and no improvement occurred in 40 patients (63.5 %). Only one complication, superimposed infection, occurred. Cryotherapy may mediates mild resolution of plaques by inducing normal re-epithelization following the physical destruction of the lesions via a reverse Koebner phenomenon. Our findings suggest that cryotherapy is safe to use in the treatment of small-plaque psoriasis but that its efficacy is limited.