URTICARIA PIGMENTOSA (Sangster) or URTICARIA XANTHELASMOIDES Tilbury Foxi Clinical Picture.—Urticaria pigmentosa develops either at birth or during the first year of life, and persists during a great part of the patient's life. It may even develop in utero (Arning, Fabry, Raab) and consists in the appearance of vivid red elevated urticarial foci, roundish in shape. The color of the spots gradually changes into brown ish red to sepia brown or yellowish; sometimes brown or sepia brown elevations remain behind, which may be arranged in crests, or in streaks, and represent a ttunorlike molluseiform type GS'obl). The affection is found on the trunk, extremities, head and face.
Course.—The eruptions may occur very frequently, especially during the first year, they then become gradually less and disappear toward the twentieth year. One solitary case has been observed to last beyond the fortieth year. Sometimes there is a slight irritability of the yasomotors, frequently erythema and wheals in the old pigmentary places, in other instances the urticarial manifestations are entirely absent and the affected places rather make the impression of a tumorlike elevation up to 1 cm. above the level of the skin. IIere and there sonie
of the effiorescences exhibit vesicular formations. Arning and Veiel have observed eczema among the complications. Urtiearia faetitia has been observed more frequently.
Pathological pigmentosa is caused by the excessive accumulation of those forms of connective tissue cells in the subepithelial tissue layer which have been described by Ehrlich as "Mastzellen" (Unita).
The etiology is unknown. Perhaps there is an inherited anomaly (Neisser) or a congenital tendency which proliferates only after birth, purposes of differential diagnosis there is only urticaria kemorrhagica (with pigmentary healing) to be considered; indeed there is no doubt that among the one-hundred published cases quite a number belong to that affection. Certainly all eases which have not originated in the first year of life should be regarded with doubt. The affection may also be mistaken temporarily for papulous syphilis, far, therapy has proved absolutely powerless. Arning has effected a cure in one case by the addition of 1.5 Gm. (22 gr.) sodium salicylate to the daily ration of milk.