An initial biopsy specimen from a nonnecrotic affected area on the hand demonstrated isolated, irregular, polarizable crystals in arterioles of the dermis and subcutaneous fat, in the absence of an inflammatory infiltrate. A von Kossa stain for calcium was negative. A visceral angiogram was consistent with polyarteritis nodosa. Based on the clinical presentation and these findings, the patient was treated with prednisone and cyclophosphamide. No improvement was noted. The patient subsequently developed atrial fibrillation, and on further investigation she was found to have cardiomyopathy. Skin biopsy specimens obtained from necrotic skin on the lower part of the legs revealed necrotic epithelium, dermal thrombosis without inflammation, and polarizable crystals in vessel walls in the deep dermis that were positive on von Kossa staining.
Necrotizing Livedo Reticularis. Arch Dermatol. 2001;137(7):957-962. doi: