Diagnosis and Monitoring of Patients with Hepatitis C Virus

The global prevalence of people with hepatitis C virus (HCV) antibodies (anti-HCV-positive) is estimated to be 115 million, and 80 million of them have an active infection (anti-HCV-positive and HCV-RNA-positive).

Most HCV-infected individuals remain asymptomatic for decades and only 25% of them achieve spontaneous viral clearance, while 75% develop chronic infection. Around 10%–20% of chronically infected patients develop liver cirrhosis or hepatocellular carcinoma and despite improvements in diagnosis and screening, the morbidity and mortality due to chronic HCV infection remain high.

Medical microbiologists at the Complejo Hospitalario Navarra (Pamplona, Spain) and their colleagues carried out a prospective study included a sample of patients attending a regional reference hospital in Spain between September 2016 and December 2017, for whom viral load (VL) quantification was required. For these patients, HCV core antigen (HCV-cAg) determination was performed in parallel. The team tested plasma or serum samples from three patient groups: new diagnosis, treatment monitoring, and treatment failure. The treatment monitoring group was tested at the beginning of treatment, at four weeks post-initiation, at the end of treatment, and at 12 weeks post-treatment completion.

VL testing was performed by RT-PCR using the Cobas 6800 system (Roche Diagnostics, Mannheim, Germany), with a linear range of between 15 and 108 IU/mL. The detection and quantification of HCV-cAg was performed by chemiluminescence immunoassay (CLIA) in an Architect system (Architect HCV core antigen; Abbott Diagnostics, Wiesbaden, Germany), with a linear range of between 0 and 20,000 fmol/L. For the detection of anti-HCV antibodies, the Architect (Architect HCV anti-Ab) and Liaison (DiaSorin, Saluggia, Italy) systems were used, and/or confirmed with INNO-LIA (Innogenetics, Fujirebio, Gent, Belgium). Viral genotype and subtype data were determined by reverse hybridization assay Versant HCV Genotype 2.0 (LiPA; Siemens Healthcare Diagnostics, Tarrytown, NY, USA).

The scientists reported that a total of 303 samples from 124 patients were analyzed and there was excellent correlation was seen between HCV-cAg and HCV-RNA. The optimal cut-off value was 3 fmol/L in the receiver operating characteristics curve analysis, and the area under the curve was 0.987 (95% confidence interval 0.972–1.000). HCV-cAg sensitivity and specificity were 97% and 95%, respectively. Most diverging results were observed in the treatment follow-up group.

The authors concluded that the hepatitis C virus core antigen demonstrated good sensitivity and specificity as a marker for the detection of active HCV infection in the diagnosis of new cases, for the detection of antiviral therapeutic failures, and for monitoring of the antiviral treatment. The study was published in the December, 2019 issue of the International Journal of Infectious Diseases.

Related Links:
Complejo Hospitalario Navarra
Roche Diagnostics
Abbott Diagnostics
DiaSorin
Fujirebio
Siemens Healthcare Diagnostics