Cold globulinemic syndrome 1995 Invernizzi criteria: ① cold precipitation ratio > 1% for at least 1 month; ② at least 2 of the following 3 symptoms: purpura, weakness, arthralgia. ③Complement C4>8mg%. ④Serum RF(+). ⑤ Bone marrow biopsy with microlymphoma-like nodules. (⑥Secondary if there is concurrent connective tissue disease, chronic liver disease, lymphoproliferative disease and infection; primary if there is no any verifiable disease. (7) The presence of vasculitis was determined primarily on the basis of liver, kidney, or peripheral neuropathy.