Evolving strategy for HCV testing in an Italian tertiary care hospital

Abstract

Background: Diagnostic tests for hepatitis C virus (HCV) infection should be adapted according to the clinical status of the patient.

Objectives: We exploited the application of different HCV diagnostic algorithms in a tertiary care hospital practice.

Study design: The laboratory clinical reports to the medical orders for HCV testing during three years were clustered by different combinations of assays for anti-HCV antibodies (HCV Ab) (screening and confirmatory), HCV nucleic acid (HCV-RNA), HCV core antigen (HCV Ag). The latter was the first-line assay in acute HCV infections requiring a rapid assessment of the infectious state.

Results: The majority (91.9%) of the 2726 subjects whose samples were analyzed were inpatients. Most of the patients/subjects were tested for clinical suspicion of viral hepatitis (49.2%), or occupational accident to health care professionals (20.0%). On 66% of samples HCV Ag test alone was performed and resulted positive in 116 cases (6%), while it was detected in 50.3% of anti-HCV positive samples. The agreement between HCV Ag and HCV-RNA was very high (k=0.97); HCV Ag positivity rates increased according to the signal of the HCV Ab screening test.

Conclusions: The use of different testing strategies according to the patients' history and clinical status allowed a significant reduction of the number of tests performed and the time needed to provide a diagnostic response useful for patients' management without compromising the overall diagnostic accuracy for HCV infection.

Keywords: Diagnostic algorithms; HCV antigen; HCV infection diagnosis; HCV-RNA; Hepatitis C.