Dry blood spot testing for hepatitis C in people who injected drugs: reaching the populations other tests cannot reach

Abstract

Background: Within the UK the main source of hepatitis C virus (HCV) infection is injecting drug use however diagnosing HCV in people who inject drugs (PWID) has often proved challenging. Methods: This is a prospective cohort study of all individuals living in our regoin who had received a HCV dry blood spot test (DBST) between 2009 and 2011 Testing for HCV was offered to individuals who accessed needle exchange or drug treatment services. Results: During the study 1123 DBSTs were carried out. 946 individuals had one test, 177 had a follow up test after 1 year. 295 (31.2%) individuals were HCV antibody positive on their first test. Overall 94.3% (902/956) individuals returned for the results of their test. 177 individuals were retested and there were 29 new cases. 249 individuals attended for further follow up and their PCR status was checked. 164 (65.5%) were PCR positive. All PCR positive individuals were offered further assessment for treatment and138 patients attended for review. Assessment included factors affecting treatment outcomes including viral load, genotype and degree of fibrosis. 56.8% were genotype 3. 73.3% had a low viral load (under 800,000iu/ml). Only 9.6% had a Fibroscan score above 9 kPa which suggests moderate to severe fibrosis and/or cirrhosis. 35 have commenced treatment, 16 are in the assessment period for treatment. 54 are in continued follow up and working towards treatment, 30 individuals have declined further follow up and 3 individuals died from a drugs related death. Overall we have retained in services or treated 76% (105/138) of patients who accessed care. At the end of the study sustained viral response (SVR) was available for 7 patients and all patients who completed treatment had an SVR. Conclusion: The study has shown DBST is a complementary technique for the diagnosis of HCV. We have shown that over 94% of PWID returned for their results. Many individuals have low viral loads and low fibrosis scores so that while this group of patients may be difficult to reach and may be challenging to maintain in therapy they are easier to cure.