Track

Abstract

Cryoglobulinemic vasculopathy encompasses type I cryoglobulinemic vasculopathy; a paraprotein exhibits cryoprecipitable properties, occluding microvasculature. Both type II and type III cryoglobulinemic vasculitis are Arthus type III immune complex reactions comprising a rheumatoid factor, which is monoclonal in the type II setting and is bound to polyclonal immunoglobulin. We describe an occlusive cryoglobulinemic vasculopathy in the pediatric setting presenting with recurrent angioedema. A 15-year-old female presented with a 5-month history of recurrent episodes of angioedema involving the face, periorbital area, lips, and legs. Laboratory analysis demonstrated a positive antinuclear antibody, decreased serum C4 and C5, normal C1q without C1 esterase inhibitor, and urinalysis with intermittent proteinuria. Imaging showed hepatosplenomegaly. Upper extremity livedo reticularis was observed and biopsied. The punch biopsy showed a sparse perivascular mononuclear cell infiltrate. Careful inspection under 400x revealed eosinophilic glassy precipitates within the vascular lumens of capillaries and venules; they were further highlighted by a PAS stain. Some of the material was engulfed by macrophages. There was also mast cell hyperplasia that was further highlighted by the CD117 stain. The intravascular deposits were highlighted by C3d. The case was ultimately signed out as cryoglobulinemia complicated by complement-driven secondary acquired angioedema. This case is characteristic for a nonvasculitic cryoglobulinemic vasculopathy. As the cryoprecipitates stained for C3d, this suggests they produced angioedema through an acquired C1q esterase deficiency leading to bradykinin production with subsequent histamine release. Cryoglobulinemic vasculopathy is rarely described as a cause of pediatric angioedema. The patient’s condition has since completely resolved, with rheumatological workup ongoing.