Platelet production and destruction in liver cirrhosis.

BACKGROUND & AIMS: Thrombocytopenia is common in liver cirrhosis (LC) but the mechanisms are not fully understood. The purpose of our work was to evaluate platelet kinetics in LC with different etiologies by examining platelet production and destruction. METHODS: Ninety-one consecutive LC patients (36 HCV, 49 alcoholics, 15 HBV) were enrolled. As controls, 25 subjects with idiopathic thrombocytopenic purpura, 10 subjects with aplastic anemia, and 40 healthy blood donors were studied. Plasma thrombopoietin (TPO) was measured by ELISA. Reticulated platelets (RP) were determined using the Thiazole Orange method. Plasma glycocalicin (GC) was measured using monoclonal antibodies. Platelet associated and serum antiplatelet antibodies were detected by flow cytometry. B-cell monoclonality in PBMC was assessed by immunoglobulin fingerprinting. RESULTS: Serum TPO was significantly lower in LC (29.9±18.1 pg/ml) compared to controls (82.3±47.6 pg/ml). The GC levels were higher in LC (any etiology) than in healthy cases. Conversely, the absolute levels of RP were lower in LC (any etiology) than in healthy controls. The platelet-associated and serum anti-platelet antibodies were higher in HCV+ LC compared to healthy subjects (p<0.0064), alcoholic LC (p<0.018), and HBV+ LC (p<0.0001). B-cell monoclonality was found in 27% of the HCV+LC, while it was not found in HBV+ or alcoholic LC. CONCLUSIONS: Patients with LC present decreased plasma TPO, accelerated platelet turnover, and reduced platelet production. This indicates that LC thrombocytopenia is a multifactorial condition involving both increased platelet clearance and impaired thrombopoiesis.

Serum ferritin as a predictor of treatment outcome in patients with chronic hepatitis C.

OBJECTIVES: Antiviral treatment in chronic hepatitis C (CHC) involves ribavirin, a hemolytic agent. We planned a prospective study to evaluate whether drug-induced iron perturbation is clinically relevant as it relates to therapeutic outcome. METHODS: Iron variables were sequentially assessed in 206 CHC patients undergoing antiviral therapy and were correlated with pretreatment iron status and histology, hemolysis, and therapeutic outcome. RESULTS: At week 1 of therapy, serum iron (SI), transferrin saturation (TS), and serum ferritin (SF) increased markedly in all patients. All iron parameters correlated with hemolysis up to week 4; this correlation was lost for SF at later time points. SF rise during treatment was inversely related to baseline SF and iron deposits in hepatic mesenchymal/Kupffer cells. Both baseline SF and mesenchymal iron significantly correlated with fibrosis at multivariate analysis (P=0.015 and 0.008, respectively). Interestingly, baseline SF, despite good specificity (89%), had low sensitivity in predicting siderosis (25%). During therapy, SI, TS, and hemolysis parameters did not correlate with sustained virological response (SVR), whereas SF rise became an independent predictor of therapeutic response: a 2.5-fold increase of SF at week 12 associated with higher likelihood of SVR (odds ratio 1.91, P=0.032). Accordingly, lack of mesenchymal iron deposits at the baseline biopsy correlated with SVR (odds ratio 3.02, P=0.043). CONCLUSIONS: In CHC, SF is a useful marker for assessing disease duration and progression before starting treatment and for predicting therapeutic response while on therapy. SF rise during antiviral therapy is largely independent of hemolysis and likely indicates activation of macrophages in response to antivirals.

Molecular epidemiology and interferon susceptibility of the natural recombinant hepatitis C virus strain RF1_2k/1b.

BACKGROUND: Hepatitis C virus (HCV) genotype is an important determinant of virological response to antiviral therapies. Currently, there are no data available on the molecular epidemiology and interferon susceptibility of the natural intergenotypic recombinant RF1_2k/1b (RF1) strain. METHODS: Genotyping and RF1-PCR screening were performed on samples from 604 HCV RNA-positive individuals from 7 countries. uPA/SCID mice carrying human hepatocytes (chimeric mice) were infected with the RF1_2k/1b strain, and the susceptibility of the strain to interferon and ribavirin was compared with the susceptibilities of 2 different strains of genotype B, used as references. RESULTS: Six new RF1 cases were identified in this study; 5 (2%) of 281 in Russia and 1 (1%) of 90 in Uzbekistan. Phylogenetic analyses based on Core/E1 and NS5b indicated that all RF1 representatives share a common evolutionary ancestor. Infection with RF1 was established in chimeric mice. Reduction of RF1 viral load was observed in response to 3 injections of 3 microg/kg pegylated-interferon alpha-2a alone or in combination with 50 mg/kg of ribavirin (0.5 or 1.4 log-copies/mL). CONCLUSIONS: All identified RF1-type strains appear to be introduced from a single source, suggesting that intergenotypic recombination in HCV is sporadic and not associated with cocirculation of different genotypes in a population. The RF1 strain in this study was responsive to interferon in vivo.