URTICARIA pigmentosa, although a relatively uncommon clinical entity, is nevertheless a well established and well recorded affection in its three forms. An analysis of reported cases shows that the majority, 65%, are of the macular variety, 25% of the mixed or maculonodular type, while 10% represents the purely nodular type.
In all forms, the affection, characteristically, appears as widespread numerous lesions, and while the number may vary, cases showing few lesions are quite uncommon. Indeed, the literature cites only a few examples with few lesions and still fewer with just a single lesion. Little refers to a patient whose eruption was limited to two lesions. Gross and Novy each presented a case with a single nodule of urticaria pigmentosa, and recently Scott and Lewis reported another such example.
In the past two years, in conjunction with other dermatologists, we have had the opportunity to study seven cases, all in