Molecular biology and clinical implication of hepatitis C virus

Hepatitis C virus (HCV) was first described in 1989 as the putative viral agent of non-A non-B hepatitis. It is a member of the Flaviviridae family and has been recognized as the major causative agent of chronic liver disease, including chronic active hepatitis, cirrhosis and hepatocellular carcinoma. HCV is a positive RNA virus with a genome containing approximately 9500 nucleotides. It has an open reading frame that encodes a large polyprotein of about 3000 amino acids and is characterized by extensive genetic diversity. HCV has been classified into at least 6 major genotypes with many subtypes and circulates within an infected individual as a number of closely related but distinct variants known as quasispecies. This article reviews aspects of the molecular biology of HCV and their clinical implication.

Liver biopsies in patients with lysosomal storage disease: experience with effective sedation.

We prospectively applied a protocol used to sedate children who required a liver biopsy. Sixty liver biopsies were performed on thirty pediatric patients to assess the effects of treatment. Sixteen patients had Type 1 Gaucher's disease of which seven had a platelet count between 50-100,000/mm3. All seven had bleeding time performed and when indicated, intravenous DDAVP (1-deamino-8-D-arginine vasopressin) was used to improve hemostasis. Fourteen patients had Niemann-Pick disease type C of which eight were significantly demented and uncooperative. Before liver biopsy, all patients were sedated with the following regimen: oral chlorpromazine (1 mg/kg) followed one hour later by intravenous meperidine (1 mg/kg) and pentobarbital (maximum dosage 6 mg/kg) administered by slow intravenous injection. Liver biopsies were obtained safely on all patients. Only 1 patient (2%) developed a potentially serious complication: an obstructed airway which was readily corrected by simple repositioning. Transient less serious complications occurred in another 7 patients (12%). There was no long term sequalae of the biopsy procedures. Our study indicates that with appropriate patient selection, this sedation protocol may be useful in pediatric patients requiring a liver biopsy.