CD40LG and Waldenstrom macroglobulinemia: A WM-associated nephropathy and hyperviscosity syndrome was diagnosed according to the International Prognostic Scoring System for Waldenström macroglobulinemia [7], and the patient was treated with RCD (cyclophosphamide and dexamethasone and 1 week later rituximab to avoid symptomatic IgM flare) without plasmapheresis because of a favorable evolution within the first week.