HEPATITIS-C VIRUS POLYMERASE CHAIN-REACTION - ENHANCED SENSITIVITY BY AMPLIFICATION OF SHORT CDNA FRAGMENTS

The aim of our study was to compare the sensitivity of hepatitis C virus polymerase chain reaction (HCV-PCR) by use of two different primer sets which amplify PCR products of different length. Serum samples of 70 patients with chronic hepatitis C were tested by "nested primer" PCR, using either "NCR primers" that amplify cDNA-fragments of 340 basepairs (bp), or by "PT primers" which amplify fragments of 59 bp only. HCV-RNA was detected in 40 patients (57%) by "NCR primers" and in 69 patients (90%) by "PT primers" (p< 0,001). 23 of 70 patients (33%), which were HCV-RNA negative by "NCR primers", were positive by "PT primers", but no patient negative by "PT primers" was found to be positive by "NCR primers". 20 healthy controls tested by both primer sets were all HCV-RNA negative. We conclude that the sensitivity of HCV-PCR is significantly improved by use of primers that amplify "short" PCR products and recommend the use of "PT primers" for HCV-PCR.