History: 14-year old male with dermatosis affecting his entire skin excepting face, genitals and oral mucosa. Dermatosis consists of a marked thickening of the skin (more evident on elbows), with large areas where the keratotic skin has "shed off" and looks almost normal. there's a peculiar smell (rancid butter-like). According to the patient's mother he's had this condition since the 1st day after he was born. Diagnosis: Epidermolytic hyperkeratosis