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.