Sjögren's syndrome plasma cell panniculitis and hidradenitis.

We present a 42-year-old woman with primary Sjögren's syndrome and a polyclonal gammopathy who presented with pretibial petechiae, purpura, and tender indurated plaques. The indurated plaques revealed a lobular plasma cell panniculitis, and thus Sjögren's syndrome should be added to the short list of collagen vascular diseases that can present as plasma cell panniculitis. Her biopsies also demonstrated intense perieccrine plasma cell infiltrates that may account for Sjögren's syndrome-associated hypohidrosis. We also observed occasional vascular occlusion of vessels with an amorphous, eosinophilic material possibly related to her hypergammaglobulinemic purpura.