S12C22bP12b-2: Loose traceries of histiocytes extend on the left among slightly altered collagen bundles. There are occasional giant cells. To the right of this zone, the dermis is relatively acellular. There are fibrin deposits among the collagen bundles. The patterns could be accommodated in category of granuloma annulare, if this were the only field available for examination. From a most general perspective, the area to the right qualifies as necrobiosis.

S12C22bP12b-5: Focally, the lymphoid infiltrates are rich in plasma cells. A plasmacytosis of this degree would be most unusual in a lesion of granuloma annulare. There has been no evidence of a paraproteinemia in this patient. Plasma cells, as seen in the infiltrates of this lesion, are common in the infiltrates of necrobiosis lipoidica; they generally are not a feature of granuloma annulare. Lesions of this type can be accommodated in the category of Miescher’s granuloma. The definition of Miescher’s granuloma is imprecise; for some articles purporting to represent Miescher’s granuloma, the photomicrographs seem to be more characteristic of actinic granuloma (see photomicrographs in Mehregan’s contribution). To classify this type of lesion (as seen in figures S12C22a&bP12a&b) as atypical necrobiosis lipoidica is an equally imprecise characterization; there are many features of necrobiosis lipoidica that are not represented in this lesion.