Extensive psoriasis induced by pegylated interferon alfa-2a and ribavirin in the treatment of chronic hepatitis C.

A 56-year-old man with chronic hepatitis C was treated with pegylated interferon alfa-2a in combination with ribavirin. However, psoriatic lesions appeared and worsened dramatically during therapy. Because of the extensive skin eruptions, he stopped therapy for chronic hepatitis C and subsequently started narrow-band ultraviolet B phototherapy and topical calcipotriol/betamethasone dipropionate ointment. After this, the psoriasis improved in a slow but comprehensive manner. Our case suggests that physicians should keep in mind the possibility of psoriasis as a side effect of interferon treatment for chronic hepatitis C.