Lipoid proteinosis: report of a possible localized form on both hands and wrists

A 28-year-old woman was seen for pruritic lesions on both hands and wrists which had been present since the age of 10 years. Both palms showed symmetric, diffuse hyperkeratosis extending over both wrists and the dorsal aspects of both hands with well-demarcated, erythematous, lichenified plaques (Figs 1 and 2). The borders of the plaques were pigmented and studded with papules (Fig. 2). The skin lesions were not related to sun exposure. No similar lesions were found elsewhere on the body. The hair, nails, and dental development were normal. A skin biopsy was taken for histopathologic and ultrastructural studies under the clinical impression of pityriasis rubra pilaris. Microscopically, homogeneous perivascular deposits of hyaline-like material were seen in the papillary and reticular dermis, accompanied by mononuclear cells (Figs 3 and 4). The overlying epidermis was acanthotic with hyperkeratosis (Fig. 3). The hyaline deposits were positive for periodic acid-Schiff (PAS) and oil-red O stains (Figs 5 and 6). Congo red stain was negative. Electron microscopic examination showed abundant amorphous material intermingled with short collagen fibrils in the dermis and around the blood vessels (Figs 7 and 8). Further examination revealed that the patient could protrude her tongue freely. The oral mucosa and vocal cords were smooth. There was no sign of systemic amyloidosis. The patient's complete blood cell count, biochemical tests, and protein electrophoresis were all within normal limits. Antinuclear antibody was negative. Results of porphyrin screening tests were negative for uroporphyrins and coproporphyrins in the urine and feces. The possibility of porphyria was therefore excluded. Both neurologic and ophthalmic examinations were negative. No intracranial calcification was found on a skull X-ray examination. The patient was treated with topical steroid and urea. She was lost to follow-up.