The skin biopsy specimen revealed a superficial and deep perivascular, interstitial and periadnexal infiltrate of lymphocytes and histiocytes. Focal excoriation and mild spongiosis of the epidermis were observed. A periodic acid–Schiff stain was negative for fungi. Immunostains were performed to delineate the nature of the infiltrate. The results of staining were negative for the presence of CD19, CD30, and CD34. An S100 protein stain showed several positive cells, most of which were dendritic. CD3 and CD43 stains showed many positive cells within the infiltrate. CD20 stains showed a few scattered positive cells.
Unilateral Eruption in a Child. Arch Dermatol. 2002;138(10):1371–1376. doi:10.1001/archderm.138.10.1371