Hepatitis C virus infection in dialysis and chronic liver patients: Viraemia dependent anti-E2-antibody response

Utility of routine real time quantitative PCR monitoring of HCV infection in haemodialysis patients

BACKGROUND

Hepatitis C virus (HCV) infection causes significant morbidity and mortality in patients of end stage renal disease (ESRD) on haemodialysis (HD). Stringent screening methods can help in its early diagnosis.

OBJECTIVE

The study addresses the utility of real-time quantitative polymerase chain reaction (RQ-PCR) in the diagnosis and monitoring of HCV infection especially on seronegative and normal serum alanine aminotransferase (ALT) HD patients.

MATERIAL AND METHODS

This retrospective study was carried out from January 2010 to December 2012. Patients of ESRD on maintenance HD and on whom all the three assays HCV antibody serology, PCR and ALT were done were included in the study (n=123). Group 1 (n=57), comprised of patients with negative serology and normal ALT, and Group 2 (n=66), had either raised ALT and or a positive or equivocal serology.

RESULTS

Out of the 123 cases studied, HCV serology was positive in 36.5% (45), ALT raised in 18.6% (23) and PCR positive in 67.4% (83) cases. PCR positivity was significantly higher than serology and raised ALT. Group 2 had a significantly higher PCR positivity than Group 1 (P=0.0004), but 50.9% patients of Group 1, were also PCR positive and 69% of them had a high viral count of >8×10(5) IU/ml at the time of detection.

CONCLUSION

Regular routine screening of HCV by RQ-PCR in ESRD patients can help in early diagnosis of HCV infection in patients with low index of suspicion.

Hepatitis C inflection in dialysis patients: a link to poor clinical outcome?

Among the 350,000 maintenance dialysis patients in the USA, the mortality rate is high (20-23% per year) as is the prevalence of hepatitis C virus (HCV) infection (5-15%). An additional same number of dialysis patients in the USA may be infected with HCV but have undetectable HCV antibodies. Almost half of all deaths in dialysis patients, including HCV-infected patients, are due to cardiovascular disease. Since over two-thirds of dialysis patients die within 5 years of initiating dialysis and because markers of malnutrition-inflammation complex syndrome (MICS), rather than traditional cardiovascular risk factors, are among the strongest predictors of early death in these patients, the impact of HCV infection on nutritional status and inflammation may be a main cause of poor survival in this population. Based on data from our cross-sectional and limited longitudinal studies, we hypothesize that HCV infection confounds the association between MICS and clinical outcomes in dialysis patients and, by doing so, leads to higher short-term cardiovascular events and death. Understanding the natural history of HCV and its association with inflammation, nutrition and outcomes in dialysis patients may lead to testing more effective anti-HCV management strategies in this and other similar patient populations, providing benefits not only for HCV infection but the detrimental consequences associated with this infection. In this article, we review the link between the HCV infection and mortality in dialysis patients and compare HCV antibody to molecular methods to detect HCV infection in these individuals.

De novo HCV infection among dialysis patients: a prospective study by HCV core antigen ELISA assay

BACKGROUND

Dialysis patients remain a high-risk group for hepatitis C virus infection. The current diagnosis of hepatitis C virus in dialysis patients includes serological measurement of anti-hepatitis C virus antibody; however, nucleic acid amplification technology for assessing hepatitis C virus viraemia is commonly used in other populations. An enzyme-linked immunosorbent assay test for detecting antibody to hepatitis C nucleocapsid core antigen (hepatitis C virus core antigen) in human serum has been recently developed (hepatitis C virus Core Antigen enzyme-linked immunosorbent assay test). It is conceived for screening of donor blood products to significantly reduce the 'serologic window' occurring before seroconversion during acute hepatitis C virus.

AIM AND METHODS

A cohort (n = 72) of patients on maintenance haemodialysis in a single unit in the years 2000-2003 was included. Study patients were tested monthly by hepatitis C virus Core Antigen enzyme-linked immunosorbent assay in a prospective, clinical trial. Routine results obtained by hepatitis C virus Core Antigen enzyme-linked immunosorbent assay test were confirmed by assessing hepatitis C virus viraemia by branched-chain DNA (bDNA) signal amplification assay.

RESULTS

De novo hepatitis C virus infection was identified in three patients during the study period; the hepatitis C virus incidence was 1.38% (95% confidence intervals, 1.31-4.09) per year. In each patient, hepatitis C virus core antigen testing allowed the serological identification of acute hepatitis C virus before anti-hepatitis C virus seroconversion. Hepatitis C virus RNA testing confirmed the results obtained by hepatitis C virus Core Antigen enzyme-linked immunosorbent assay in all cases. The time from initial hepatitis C virus detection by hepatitis C virus Core Antigen Assay and anti-hepatitis C virus seroconversion was not greater than four weeks. Two (67%) of three patients with de novo hepatitis C virus acquisition were HBsAg negative; both these patients underwent an initial phase of hepatitis C virus viraemia that was associated with an increase in alanine aminotransferase activity and preceded the seroconversion to anti-hepatitis C virus antibody. Nosocomial transmission of hepatitis C virus between haemodialysis patients was implicated in at least two (67%) of these three patients.

CONCLUSIONS

Serological testing for hepatitis C virus core antigen can identify acute hepatitis C virus infection before anti-hepatitis C virus seroconversion. The time from initial hepatitis C virus detection by hepatitis C virus core antigen assay and anti-hepatitis C virus seroconversion was not >4 weeks. De novo acquisition of hepatitis C virus in haemodialysis was associated with a rise in alanine aminotransferase levels. Hepatitis C virus core antigen enzyme-linked immunosorbent assay test results can be obtained in routine laboratories without the need of special equipment or training. Hepatitis C virus core antigen testing among anti-hepatitis C virus negative patients on maintenance dialysis is suggested in order to early assess de novo hepatitis C virus within dialysis units.