For the last several years we have been studying a peculiar dermatosis observed principally in dark skinned people. This skin condition affects the face and neck in the form of irregular macules and patches, slightly inflammatory, slightly scaly, of a dirty white color and somewhat itchy. These characteristics led us for some time to consider the condition a form of dry seborrhea, the seborrhéide of the French. The condition was extremely rebellious to treatments that are as a rule successful in cases of seborrhea. This, together with the fact that the lesions were of achromic appearance, slightly or not at all scaly, dry and smooth, and that there were a few cases in which the condition was generalized without any inflammatory symptoms, decided against the diagnosis of seborrhea and in favor of some skin condition unknown to us, and which we could not find in the literature at our disposal.
PARDO-CASTELLO V, DOMINGUEZ MM. ACHROMIA PARASITARIA. Arch Derm Syphilol. 1924;9(1):82–95. doi:10.1001/archderm.1924.02360190085006