A number of skin eruptions, similar in many respects, are conveniently grouped under this caption. They have been variously named as follows: Parakeratosis, variegata (Unna); erythrodermie pitryiasisque en plaques disseminess (Brocq); lichen variegatus (Crocker); dermatitis variegata (Boeck); dermatitis psoriasiformis nodularis (Jadassohn); lichenoid eruption (Neisser); pityriasis lichenoides chronica (Juliusberg). Brocq in a later contribution on this subject, describing all these conditions under the general term parapsoriasis, divides them into three groups: those that resemble psoriasis; those that are lichenoid; and those that closely resemble dermatitis seborrhoica. These conditions are usually characterized by circumscribed, well-defined, pinkish red, slightly elevated patches, from two to six cm. in diameter, covered with a fine pityriasis scaling, with little if any itching and almost complete lack of infiltration. They invariably run a slow course. Their distribution is not typical and may be localized or generalized.
Prognosis and Treatment. A marked resistance to local applications is quite typical of these conditions. Although such local measures as are applied in psoriasis are indicated, the only successful treatment reported has been the vigorous and persistent application of pyrogallic acid externally, and the internal use of large doses of dilute hydrochloric acid to counteract the poisonous effects of the pyrogallol absorption.