Clinical application and analysis of hepatitis C virus NS3 antigen detection by ELISA in human serum.

BACKGROUND: Hepatitis C virus (HCV) core antigen assays have been produced to exclude infectious donations collected during the preseroconversion window phase (PWP). For the same purpose, we evaluated the specificity and sensitivity of a novel hepatitis C virus NS3 antigen detection immunoassay and the application of this assay in clinical diagnosis. METHODS: Samples from 77 healthy subjects, 173 anti-HCV positive patients and 3708 hepatitis patients other than HCV positive were tested with the HCV NS3 antigen assay. Some HCV NS3 antigen positive samples were further validated with HCV-RNA, neutralization and immunodot assays. Twenty-five sequential samples from 11 HCV NS3 antigen positive patients were subjected to kinetic study. RESULTS: Only 48 (1.3%) of 3708 anti-HCV negative samples were positive for HCV NS3 antigen. Among them, 44 of 3030 samples from patients only infected with HBV were HCV NS3 antigen positive, 4 of the 445 samples from patients infected with other type hepatitis were HCV NS3 antigen positive. In addition, 42 (24.3%) of 173 anti-HCV positive samples were HCV NS3 antigen positive and all 77 samples from healthy subjects were negative to HCV NS3 antigen assay. Of the 15 HCV NS3 antigen positive samples, 9 (60%) were HCV-RNA positive. The neutralization and positive percentage of immunodot assay for 23 HCV NS3 antigen positive sera were 87.0% (20/23) and 69.6% (16/23) respectively. Of the 25 sequential samples from 11 HCV NS3 antigen positive patients, there was a negative correlation between the OD values and the duration of test (r = -0.989, P < 0.05), and there were correlations among their HCV NS3 antigen, HCV-RNA and anti-HCV titres. The anti-HCV antibodies of two sera were detected while their OD values of HCV NS3 antigen decreased gradually. CONCLUSIONS: The HCV NS3 antigen detection assay showed perfect specificity and high sensitivity. Thus, it would be useful and economical as a routine test in laboratories for early diagnosis of HCV infection and prevention.

[Survival analysis on liver failure patients treated with an artificial liver support system].

OBJECTIVE: To evaluate the efficacy of artificial liver support system (ALSS) in the treatment of liver failure patients. METHODS: This is a prospective, multi-center, controlled, large sample clinic trial. 518 patients with liver failure from 5 hospitals were studied and followed. All the patients received similar pharmacological manipulation according to one and the same protocol but were divided into an ALSS treatment group and a control group without ALSS treatment. The ALSS treatment procedures included plasma exchange, molecular adsorbent recirculating system (MARS), plasma exchange plus hemofiltration and other combined nonbioartificial methods. The analysis of survival time was computed using the Kaplain-Maier method, and comparison among groups was done using Log-Rank, Breslow and/or the Tarone-Ware test. RESULTS: Survival time of acute liver failure patients was prolonged from 4.0+/-0.2 days to 8.0+/-0.4 days (P=0.004). ALSS was shown to be two times more effective. ALSS increased the survival time of acute on chronic (A on C) liver failure patients from 27.0+/-1.6 days to 39.0+/-4.0 days (P less than 0.01). In addition, it increased the survival time of the patients in the middle and end stage of subacute liver failure and A on C liver failure, but had no significant effects on early stage patients. The survival time of middle stage patients was 38.0+/-17.5 days in the control group vs 66.0+/-18.6 days in the ALSS group (P less than 0.05). The survival time of end stage patients of the control group and the ALSS group was 18.0+/-4.0 days vs 26.0+/-2.5 days (P less than 0.01). CONCLUSIONS: Multi ALSS treatment is more effective than the standard medicinal liver care treatment. Multi-ALSS treatment could increase survival time of patients suffering from acute liver failure or A on C liver failure, especially in their middle and end stages. It is important and necessary to treat these patients with ALSS.

Interferon-alpha induced severe thrombocytopenia: a case report and review of the literature.

We report a case of severe thrombocytopenia following pegylated interferon-alpha 2a (Peg-IFN-alpha 2a) treatment of hepatitis C virus infection and summarize the clinical characteristics of 16 cases of IFN-alpha induced severe thrombocytopenia and its immune-mediated mechanism. Discontinuation of IFN-alpha and early administration of immunosuppressants are the effective therapy for IFN-alpha induced severe thrombocytopenia.