Outcomes and costs of single-step hepatitis C testing in primary care, Birmingham, United Kingdom

Abstract

Objectives: In UK laboratories, the diagnostic algorithm for chronic hepatitis C (HCV) infection commonly requires two serological assays to confirm anti-HCV-antibody positivity in a serum sample followed by HCV RNA detection in a second whole-blood sample (two-step testing algorithm). A single-step algorithm (both anti-HCV antibodies and RNA tested on an initial serum specimen) has been advocated to reduce attrition rates from the care pathway.

Study design: To investigate the feasibility, clinical impact and relative costs of switching from a two-step to single-step testing algorithm in the laboratory, a pilot study on unselected primary care requests was undertaken.

Methods: All primary care patients tested for HCV infection from December 2013 to April 2016 were included. The single-step testing algorithm was introduced in March 2015. Before this, the two-step algorithm was used. Patients were followed up until August 2016.

Results: RNA quantitation in plasma was within one log of serum values for 21 paired samples. Although all patients in the single-step algorithm received an RNA test, only 70% completed the two-step testing algorithm; differences in referral rates to specialist care was due to 30% of HCV antibody-positive patients in the two-step algorithm not having follow-up whole-blood sampling for HCV RNA testing. Costs per new diagnosis and new diagnosis referred to specialist care were lower in single-step testing by £94.32 and £144.25, respectively.

Conclusion: This study provides further evidence that a single-step testing algorithm, as recommended in the UK Standards for Microbiology Investigation, works in practice and should be the standard of care for screening for chronic HCV.

Keywords: Clinical laboratory techniques; Continuity of patient care; Hepatitis C; Quality improvement.