title: Hepatitis C genotype analysis: results in a large veteran population with review of the implications for clinical practice.
abstract: BACKGROUND
  Hepatitis C virus (HCV) infects up to 1.8% of the US general population, although the rate is significantly higher in military veterans at 5.4-20%. Early detection and accurate diagnosis are critical as chronic HCV infection can lead to liver cirrhosis and hepatocellular carcinoma. Genotype analysis has both therapeutic and prognostic importance in patients with HCV infections.
  
  
  OBJECTIVE
  We compare two versions of a commonly utilized platform for genotype analysis in HCV infections and review the implications of the results for clinical practice.
  
  
  METHODS
  A retrospective review of 9401 genotype results from 2001-2010 were analyzed. All results were obtained from the James A. Haley VA Medical Center, a large referral veterans' healthcare facility.
  
  
  RESULTS
  Genotype 1 was identified in 80.1% of samples, genotype 2 in 11.1%, genotype 3 in 7.4%, and genotype 4 in 1.2%. Genotypes 5 and 6 were rarely present in our patient population. Improvements in diagnostic methodologies over the study period resulted in shifts in genotype subtyping. Specifically, upgrading from the Versant HCV genotype assay (LIPA) (Siemens, Tarrytown, NY) to the newer version 2.0 assay resulted in an increase in identification of genotype 1a by 18.5%.
  
  
  CONCLUSIONS
  Improved technologies lead to accurate genotype identification and subtyping, both of which have increasingly important prognostic and therapeutic implications. The clinical importance of these results in patients with HCV infections is reviewed.
authors.affiliation: Pathology and Laboratory Medicine, James A. Haley Veterans Hospital, Tampa, FL 33612, USA. Lamar.Thomas@va.gov
authors.forename: L Brannon
authors.initials: LB
authors.lastname: Thomas
authors.forename: Philip R
authors.initials: PR
authors.lastname: Foulis
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Mastorides
authors.forename: Yao A
authors.initials: YA
authors.lastname: Djilan
authors.forename: Oswald
authors.initials: O
authors.lastname: Skinner
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Borkowski
mesh_terms: D005431:Florida; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics*; D006526:Hepatitis C / Q000175:diagnosis*; D006801:Humans; D007211:Indoles; D009580:Nitroblue Tetrazolium; D012189:Retrospective Studies; D014728:Veterans; D019562:Viral Load
chemical_list: D007211:Indoles; D009580:Nitroblue Tetrazolium; C035455:5-bromo-4-chloro-3-indoxyl phosphate