No abstract

No abstract

Persistent viremia after clinical or subclinical hepatitis C virus (HCV) infection is believed to occur in patients with chronic hepatitis C, but little is known about the duration of HCV replication in patients with acute hepatitis who have recovered or the relation of HCV viremia with the kinetics of antibodies to HCV (anti-HCV). We tested HCV-RNA and anti-HCV in serial serum samples from 41 patients with posttransfusion non-A, non-B hepatitis, followed for an average of 6 years after transfusion. Serum HCV-RNA was measured by nested polymerase chain reaction, which used primers from the 5' untranslated region of the HCV genome. Anti-HCV were tested with first- and second-generation enzyme-linked immunosorbent assays (ELISA 1 and ELISA 2), and with a second-generation recombinant immunoblot assay. Of the 41 patients, 10 recovered and 31 progressed to chronic liver disease. HCV-RNA was detected in serum before or simultaneously with the onset of hepatitis in all cases, and lasted between 2 and 6 weeks in 5 of the 10 patients who recovered, whereas it persisted for the entire follow-up period in every case with chronic hepatitis and in the remaining 5 patients with self-limiting hepatitis. Anti-HCV were detected with ELISA 2 in the first serum sample, with raised serum transaminases in 57% of patients, but in only 6% with ELISA 1. In the sample obtained 1 month after the onset of hepatitis, anti-HCV were detected with ELISA 2 in 94% of patients, but in 34% with the ELISA 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Antiphospholipid antibodies (aPLs) are associated with thrombosis, but the mechanisms of this thrombotic tendency are unknown. We studied 56 patients 612 with systemic lupus erythematosus [SLE] and aPLs and previous thrombosis, 12 with SLE and aPLs but no thrombosis, 15 with SLE without aPLs or thrombosis, 11 with primary antiphospholipid syndrome with thrombosis, and 6 asymptomatic subjects with aPLs) to investigate the ability of aPLs to induce tissue factor (TF) expression on human normal monocytes. A double direct immunofluorescence technique (anti-CD14 and anti-TF) was used, and procoagulant activity in viable and disrupted cells was measured after plasma incubation for 6 hours at 37 degrees C with normal mononuclear cells. Hemostasis regulatory proteins, prothrombin fragment 1 + 2, and thrombin-antithrombin III complex levels were determined. Increased TF expression and procoagulant activity were observed using plasma samples from SLE patients with aPLs and thrombosis (P < .01) and from primary antiphospholipid syndrome patients (P < .01) but not from patients with SLE and aPLs but no thrombosis, patients with SLE without aPLs, or asymptomatic patients with aPLs. Purified aPL immunoglobulins from one primary antiphospholipid syndrome and two SLE patients added to normal plasma showed a significant increase in both TF expression and procoagulant activity (P < .05) compared with purified aPL from two SLE patients without thrombosis. The addition of nonspecific IgG from three SLE patients without aPLs and from three control subjects did not increase TF expression. Low free protein S was seen in eight patients. Increased TF expression and low free protein S correlated with thrombosis (P < .01) and with higher prothrombin fragment 1 + 2 and thrombin-antithrombin III values (P < .01). These observations may contribute to a further understanding of the thrombotic risk in aPL patients.

No abstract