ABSTRACT
<p><b>OBJECTIVE</b>To determine whether patients infected with chronic hepatitis C (CHC) show a differential distribution profile of IL-28B polymorphisms according to the presence of concomitant cryoglobulinemia.</p><p><b>METHODS</b>Sixty-two consecutive CHC patients were enrolled in the study between December 2008 and December 2010. All patients received combination therapy of pegylated interferon alpha-2a (weekly, 180 g, subcutaneous injection) plus ribavirin (daily, 10to15 mg/kg body weight, oral) for 48 weeks, with individualized dosage adjustments according to the patient's clinical situation. Cryoglobulins were detected visibly by separation of cryoprecipitates in patient serum samples. Three IL-28B SNPs (rs8099917, rs12979860, and rs12980275) were detected by sequencing. Response to treatment was assessed by measuring serum levels of HCV RNA by quantitative PCR at baseline (prior to treatment initiation), during treatment (4 and 12 weeks after treatment initiation), end of therapy (48 weeks after treatment initiation), and post-treatment (24 weeks after end of therapy). The significance of between-group differences were assessed by the Chi-square and Fisher's exact tests.</p><p><b>RESULTS</b>Cryoglobulinemia was detected in 43.5% (27/62) of the CHC patients and showed a female bias (59.3% vs. males: 34.3%, P = 0.05). Compared to CHC patients without cryoglobulinemia, the CHC patients with cryoglobulinemia showed significantly higher levels of HCV RNA at baseline (5.64+/-1.20 vs. 6.37+/-0.67, P less than 0.05) but lower frequencies of the IL28B rs8099917 TT genotype (94.3% vs. 63.0%, P = 0.002), rs8099917 T allele (97.1% vs. 81.5%, P = 0.003), and rs12979860 C allele (94.3% vs. 83.3%, P = 0.048). CHC patients with cryoglobulinemia and having the rs8099917 TT, rs12979860 CC, or rs12980275 AA genotype achieved a higher rate of sustained virological response.</p><p><b>CONCLUSION</b>Cryoglobulinemia in CHC patients is associated with a differential distribution of IL-28B polymorphisms, and certain polymorphisms may be related to anti-viral treatment response.</p>