LPL with IgM detected on a blood test is called Waldenström's macroglobulinemia (WM).[5] LPL rarely produces a paraprotein from different types of antibodies (usually immunoglobulin G [IgG]), but in such cases it usually produces IgM and IgG.[6] Extranodal involvement, including of the gastrointestinal tract, lung, liver, spleen, skin, central nervous system, and kidney, is rare in LPL.[1,3,4]. The gene discussed is CD40LG; the disease is Waldenstrom macroglobulinemia.