478 ERYTHROPOIETIN USE FOR THERAPY ASSOCIATED ANEMIA IN HEPATITIS C VIRUS INFECTION AND RISK OF MORTALITY

samples were applied. The aim was to re-analyze sequential plasma and PBMC samples from patients who resolved CHC and became HCVRNA negative by clinical laboratory testing. Methods: Plasma samples (n = 60) from 11 randomly selected patients who resolved CHC after a standard course of PEG/IFN/RBV therapy were collected before (n = 12), during (range 48–68 wks; n =28) and up to 33.1 (range 12–88) wks post-treatment (n = 20). PBMCs (n =26) from 4 patients before (n =5), during (n =13) and post-treatment (n = 8) were also analyzed. Total RNA was extracted from 250 or 750ml plasma and intact or PHA-stimulated PBMCs. HCVRNA was detected by RT-PCR/nucleic acid hybridization (RTPCR/NAH; sensitivity <5 copies/mg RNA or <2 IU/ml). Clone sequence analysis of the HCV 5′-UTR from sequential plasma and PBMCs was done in 2 patients. Results: HCVRNA was detected in 9 of 20 (45.3%) plasma and 4 of 8 (50%) PBMC samples for up to 23.6 wks (range 12–59 wks) after completion of treatment. Among plasma samples identified during therapy as negative for HCVRNA by clinical assay, 64.3% were reactive by RT-PCR/NAH. Testing of RNA from 750ml plasma increased HCV detection from 31.7% to 63.3% (38/60) compared to 250-ml samples. Testing naive versus PHA-stimulated PBMCs enhanced HCV detection from 26.9% to 69.2% (18/26). Virus replicative strand was detected in 12/18 PBMC samples. Mutations identified in the 5′-UTR sequence persisted in plasma and/or PBMCs during and after PEG-IFN/RBV therapy. The frequency of HCV detection tended to decline in both plasma and PBMCs with longer follow-up. Conclusions: HCV can persist at levels not detectable by standard clinical assays in both plasma and PBMC after clinically apparent resolution of CHC due to PEG-IFN/RBV therapy. The findings suggest the need for continued evaluation even after patients achieve undetectable HCVRNA post-treatment.