Tacrolimus-induced Epidermoid Cysts in the Renal Transplant Patient.

Epidermal cysts are common benign cystic lesions that occur mostly sporadically. Common sites involved are arms, face, and trunk. The cyst may progress slowly and remain for years. These cysts arise as a result of the plugging of the follicular orifice. Etiology has largely remained unknown although local trauma, ultraviolet rays, and human papilloma virus (HPV) have been implicated in a few cases. Calcineurin inhibitors (CNIs) especially cyclosporine has been discredited for cutaneous side effects such as hirsutism and gingival hyperplasia. Epidermoid cysts have been also associated with patients with solid organ transplant recipients on cyclosporine. Tacrolimus is considered to be free of dermatological side effects. Herein, we report a case of 56-year-old renal allograft recipient on tacrolimus, who develop more than >100 epidermoid cysts over the face, trunk, back, and extremities. The lesions ceased to progress once the tacrolimus was stopped.