[Costa acro-kerato-elastoidosis].
We report 2 cases of acrokeratoelastoidosis of Costa observed in two sisters born of unaffected first cousins. The lesions were lenticular papules, either white or of normal skin colour, which were isolated or arranged in groups of plaques crossed by the natural furrows and located on the thenar eminences, the lateral edges of the hands and fingers and the back of the interphalangeal joints. On the feet, the lesions, located on the lateral edges, the plantar arch and the heel, were much more keratotic and appeared to be translucent. Hyperhidrosis was noted in only one of the two patients. Histological examination showed, beneath an acanthotic and hyperkeratotic epidermis, a reduced elastic network with shorter and thinner fibres in the middle dermis. These are two typical but rough cases of acrokeratoelastoidosis of Costa. The mode of transmission of this disease (autosomal recessive?) seems to be unusual compared with the data found in the literature (dominant, or sporadic cases).