Hepatitis C virus core antigen as alternative diagnostic algorithm for active hepatitis C virus infection among haemodialysis population: Cost implications

AIMS

In Malaysia, majority anti-HCV positive haemodialysis patients do not undergo hepatitis C confirmation due to the high cost of HCV RNA. HCV Core Antigen might be a cost-effective diagnostic test to identify HD patients who have active HCV infection eligible for Direct Acting Anti-viral therapy.

METHODS

A cross-sectional study was conducted to assess the correlation between HCV Ag and HCV RNA and the cost implications of different diagnostic algorithms to diagnose active HCV infection using Anti-HCV, HCV Ag, and HCV RNA. Pre-dialysis blood was tested for both HCV Ag and HCV RNA. HCV Ag was tested with Abbott ARCHITECT HCV Ag test.

RESULTS

Two-hundred twenty-seven haemodialysis patients were recruited from 20 centres with mean age of 57.68 ± 12.48 years, and male constitutes 56.8% (129) of the study population. HCV Ag correlated well with HCV RNA (Spearman test coefficient 0.943, p < .001) with sensitivity of 93.9%, specificity 99.3%, and the accuracy was 97.36%. Cost analysis indicated that a sequential test involving Anti-HCV antibody as initial screening, followed by HCV Ag on Anti-HCV positive and HCV RNA on HCV Ag negative cases translated to a modest cost-saving algorithm compared to standard diagnostic algorithm.

CONCLUSION

HCV Ag correlated well with HCV RNA and can potentially be fused in an alternative diagnostic algorithm to generate cost savings methods to diagnose active HCV infection among haemodialysis patients. This alternative algorithm is especially relevant in low to middle-income countries such as Malaysia to optimize the use of the healthcare resource and gains in clinical outcomes.

Hepatitis C core antigen testing to diagnose active hepatitis C infection among haemodialysis patients

Background

Hepatitis C virus (HCV) infects more than 71 million people worldwide and chronic HCV infection increases the risk of liver cirrhosis and failure. Haemodialysis (HD) is one of the renal replacement therapies with risk of HCV transmission. Anti-HCV antibodies are the serological screening test for HCV infection that does not detect active phase of infection. Majority HCV infected HD patients in Malaysia do not have further HCV RNA performed due to high cost and thus HCV treatment is less frequently offered. HCV Core Antigen (HCV Ag) can potentially be used to diagnose active HCV infection in HD population in comparison to HCV RNA, at lower cost.

Methods

We conducted a cross-sectional study to assess the correlation between HCV Ag and HCV RNA and to identify the prevalence of active HCV infection among HCV seropositive HD patients from dialysis centres across West Malaysia from July 2019 to May 2020. Pre-dialysis blood was taken and tested for both HCV Ag and HCV RNA tests. HCV Ag was tested with Abbott ARCHITECT HCV Ag test.

Results

We recruited 112 seropositive HD patients from 17 centres with mean age of 54.04 ± 11.62 years, HD vintage of 14.1 ± 9.7 years, and male constitute 59.8% (67) of the study population. HCV Ag correlates well with HCV RNA (Spearman test coefficient 0.833, p < 0.001). The sensitivity was 90.7%, specificity 100%, positive predictive value (PPV) 100%, negative predictive value (NPV) 76.5%, and accuracy 92.9%. For HCV RNA level > 3000 IU/mL, HCV Ag had a higher sensitivity of 95.1% and greater correlation (Spearman test coefficient 0.897, p < 0.001). The prevalence of active HCV infection was 76.8% among HCV seropositive HD patients.

Conclusions

Although HCV Ag is less sensitive, it shows an excellent correlation with HCV RNA and has 100% PPV. HCV Ag can be considered as an alternative diagnostic tool for chronic active HCV infection among HD cohort, who can then be considered for HCV treatment. For seropositive HD patient with negative HCV Ag, we recommend to follow-up with HCV RNA test.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-020-02154-4.

Serological investigation for hepatitis E virus infection in the patients with chronic maintenance hemodialysis from southwest of Iran

BACKGROUND AND OBJECTIVES

A global distribution has been shown for hepatitis E virus (HEV) infection. Although the fecal-oral was considered as the primary infection route, there is controversial evidence for increased risk of the infection and consequent problems in patients on maintenance hemodialysis (HD) with suppressed immunity. The aim is to find if the prevalence of anti-HEV IgG, in patients with maintenance HD is higher than normal population in southwest of Iran.

MATERIALS AND METHODS

During November and December 2010, in a cross-sectional study we compared the seroprevalence of HEV among 80 patients with maintenance HD and 276 healthy individuals from Jahrom and Shiraz, Southwest of Iran. In addition to the clinical and laboratory records, serum samples were tested for the presence of IgG anti-HEV antibody by enzyme immunoassay (ELISA) test. The Chi-square, the Student's 't' and Fisher's exact tests were used for the statistical analysis.

RESULTS

ELISA tests detected anti-HEV antibody in five males of the patients (6.3%) and in eight of the healthy controls (2.9%, 6 males and 2 female) which statistically were not different. The mean levels of the aspartate aminotransferase and the alanine aminotransferase in the sera of the patients were 19.96±11.08U/L and 23.93±14.26 IU/L, respectively. However, no one of the individuals with positive anti-HEV antibody showed elevated liver enzymes. Moreover, there was not a significant association between positive anti-HEV antibody result, age and the history of the hemodialysis.

CONCLUSIONS

We did not observe statistically significant higher anti-HEV prevalence among patients with chronic HD; however, more safety precaution is needed to keep HD patients from the risk of possible exposure to HEV infection.

Association of HCV core antigen seropositivity with long-term mortality in patients on regular hemodialysis

Anti-hepatitis C virus (HCV) antibody seropositivity is independently associated with poor prognosis in hemodialysis (HD) patients. However, anti-HCV antibody cannot distinguish between patients with active infection and those who have recovered from infection. We therefore aimed in this study to examine the association of HCV core antigen (HCVcAg) seropositivity with mortality in HD patients. We first measured serum HCVcAg using an immunoradiometric assay and anti-HCV antibody in 405 patients on regular HD, and followed them for 104 months. There were 82 patients (20.2%) who had been positive for anti-HCV antibodies; 57 (69.5%) of these were positive for HCVcAg. During the follow-up, 29 patients were excluded, so we tested the association of HCVcAg seropositivity with all-cause, cardiovascular (CV) and non-CV mortalities in 376 patients. A total of 209 patients (55.6%) had expired during the observational period, 92 out of them due to CV causes. After adjusting for comorbid parameters, HCVcAg was independently associated with overall mortality (HR 1.61, 95% CI 1.05–2.47, p < 0.05). HCV infection was significantly related to liver disease-related mortality. Past HCV infection also contributed to CV mortality (HR 2.63, 95% CI 1.27–5.45, p < 0.01). In contrast, anti-HCV antibody and HCVcAg seropositivities did not associate with infectious disease-related and cancer-related (expect for hepatocellular carcinoma) mortality. It follows from these findings that HCVcAg serology is associated with all-cause and CV mortality in HD patients.

Rapid early HDV RNA decline in the peripheral blood but prolonged intrahepatic hepatitis delta antigen persistence after liver transplantation

BACKGROUND & AIMS

Chronic HDV infection is an inflammatory liver disease and liver transplantation (LTX) remains the only curative treatment option for most patients. The hepatitis D virus (HDV) uses HBsAg as its surface protein, however, it is controversial to what extend HDV may be detected independently of HBsAg in blood and liver after LTX. The aims of this study were to investigate kinetics of HDV RNA and HBsAg early after LTX, to apply the data to a mathematical model and to study long-term persistence of HDV after LTX.

METHODS

We retrospectively analyzed 26 patients with chronic hepatitis delta who underwent LTX between 1994 and 2009. Blood samples were obtained every 1-3 days during the first 14 days after LTX. Data were applied to a mathematical model to study viral kinetics. Available liver biopsy samples were stained for HBV and HDV viral antigens and tested for HBV DNA/cccDNA.

RESULTS

HBsAg and HDV RNA became negative after a median of 5 days (range 1-13) and 4 days (range 1-10), respectively. Early HDV RNA and HBsAg decline paralleled almost exactly in all patients; however the mathematical model showed a high variability of virion death. HDAg stained positive in transplanted livers in six patients in the absence of liver HBV DNA/cccDNA, serum-HBsAg, and HDV RNA for up to 19 months after LTX.

CONCLUSIONS

HDV RNA and HBsAg decline follow almost identical kinetic patterns within the first days after LTX. Nevertheless, intrahepatic latency of HDAg has to be considered when exploring novel concepts to withdraw HBIG.