Recurrent hepatitis and acute rejection share common features which diagnosis difficult in liver transplant hepatitis C virus (HCV) positive patients.
In this study, researchers from Italy assessed quantitative monitoring of HCV RNA and immunoglobulin (Ig)M anti-HCV in the differential diagnosis between recurrent hepatitis and acute rejection.
They studied 98 consecutive anti-HCV positive liver transplant patients.
The research team measured aminotransferase levels, serum HCV RNA and IgM anti-HCV at the time of transplantation, and monthly thereafter.
Furthermore, the researchers obtained a liver biopsy (LB) when serum aminotransferase levels increased to greater than twice normal.
The research team observed 86 aminotransferase flares, during a mean follow-up of 16 months.
They found that histology was compatible with recurrent hepatitis C in 44 cases, with acute rejection in 28, and inconclusive in 14.
The fluctuations of HCV RNA serum levels were not significantly different in the 3 groups.
|Serum IgM anti-HCV levels increased in 82% of cases with recurrent hepatitis C.|
|Journal of Viral Hepatitis|
However, serum IgM anti-HCV levels increased in 36 of 44 cases with recurrent hepatitis C at the time of the alanine aminotransferase (ALT) flare.
Furthermore, IgM anti-HCV remained unchanged in all rejection cases.
It also increased in 10 of 11 histologically doubtful cases that were diagnosed as hepatitis at a second LB.
Increasing serum levels of IgM anti-HCV at the time of ALT flares are significantly associated with recurrent hepatitis C in liver transplant patients.
Dr Ciccorossi's team concluded, "Quantitative monitoring of IgM anti-HCV appears to be an additional diagnostic tool for distinguishing recurrent hepatitis C from acute graft rejection with a 100% specificity, 100% positive predictive value and 89% diagnostic accuracy".