Progressive atrophy of the skin is an affection of great importance on account of the causes producing it and the conclusions which we can derive therefrom. Cases of this affection have been reported by Buchwald, Touton, Colombini, Elliott, Bronson, Pospelow, Neuman, Ohmann-Dumesnil, Popoff, Jadassohn, Unna, Krzysztal-owicz and others. In some of the cases the morbid process producing atrophy of the skin was known, in others it was perfectly obscure. From the study of all the reported cases Unna gave his classification of the atrophies of the skin as idiopathic and deuteropathic, calling idiopathic the cases where the skin is primarily affected, without progressed morbid process, and deuteropathic the cases of atrophy where the skin falls into atrophy secondarily on account of a tubercular, syphilitic or other process which has damaged its stroma.
Our case belongs to the first group, the affection occurring primarily on the skin. The idiopathic atrophies