The patient was a 35-year-old man with thickened yellow plaques on his palms and soles for as long as he could remember. More recently, scale had also developed in these areas. He was otherwise healthy and had no associated skin findings on his torso, thighs, or arms. Joint examination was normal. At one time or another, the patient had tried petroleum jelly, 5% lactic acid-containing creams, and 10% urea creams, all to no avail. He used no prescription medications—topical or oral—on a regular basis. Other members of his father’s family had a similar condition.
A 20-year-old woman presented with a three-month history of a “hand rash.” The rash did not itch or burn and was not painful. Triamcinolone cream 0.1% prescribed by the patient’s primary-care clinician did not cause the eruption to disappear. A KOH preparation revealed no fungal hyphae or spores. The patient, a student, did not admit to any occupational exposures to possible allergens. She did not use any hand cream regularly or have any other medical problems. There was no family history of a similar eruption. The patient underwent biopsy and patch testing.