Cryofiltration apheresis for treatment of cryoglobulinemia associated with hepatitis C.

Cryofiltration apheresis (CA) is a specific therapy for treatment of patients with cryoglobulinemia. We evaluated the safety and efficacy of CA in patients with mixed cryoglobulinemia associated with hepatitis C. As reported previously, the Cryoglobulin Filter comprises a membrane module inside a refrigeration unit on-line with a Spectra Apheresis System (COBE, Denver, CO). The efficacy of cryofiltration was measured by comparing the sieving coefficient of cryoprecipitable proteins (CPP) to that of albumin and comparing the systemic CPP concentration ratio post to pre treatment. Five patients were enrolled in this study, and a minimum of 10 procedures were performed for each patient. The risk for hepatitis C was multiple blood transfusions, intravenous drug abuse, immunosuppressive therapy, or renal transplantation. Four patients had Type II mixed cryoglobulinemia, and one patient had Type III. Four patients had chronic renal failure; one with liver cirrhosis received alpha interferon along with CA. One patient had no response to conventional plasma exchange and immunosuppressive therapy secondary to repeated infections and sepsis; CA was the only viable therapy for this patient. The maximum CPP concentration before therapy ranged from 1,440 to 7,440 micrograms/ml. The plasma CPP sieving coefficient at 1 L filtrate ranged from 0.25 to 0.74 (average +/- SE, 0.51 +/- 0.19; n = 39). The sieving coefficient for albumin was 1 (n = 50). The systemic CPP ratio post to pre treatment ranged from 0.28 to 0.83 (average +/- SE, 0.59 +/- 0.20; n = 37). No adverse effects specific to CA were observed. The CA was safe and effective and possibly the only choice of therapy in patients with cryoglobulinemic hepatitis C who have no response to plasma exchange and immunosuppressive therapy.