Long-term histological evolution of liver graft is largely unknown. We report the histological features of liver biopsies performed routinely at 10 years after liver transplantation (LT).
Methods
At our center, liver biopsies (LB) are performed at about 10 years after LT. Two pathologists (*) reviewed 156 available biopsies. Patients (75 M / 81 F) at a mean age of 44 (range 9,53) years were transplanted before 1990 for HBV (23), HDV (29) and HCV (16) cirrhosis, primary biliary cirrhosis (PBC) (26), fulminant hepatitis (FH) (27), auto-immune hepatitis (AIH) (11), hepatocellular carcinoma (HCC) (12) (3 non cirrhotic and 9 above numbered cirrhotic livers), primary sclerosing cholangitis (PSC) (5) and other diagnoses (16).
Results
Recurrent disease was observed in 40 cases (25%). They were 10/23 for HBV cirrhosis, 3/ 29 for HDV cirrhosis, 13/16 for HCV cirrhosis , 11/26 for PBC, 3/17 for FH.
Chronic hepatitis (CH) related to acquired HCV infection was present in 53 patients (34%). In 15 cases, HC was concomitant with chronic rejection (CR) (11) or recurrence of the disease (4). CH related to acquired HBV infection was present in 2 cases.
Bile duct loss > 20% was observed in 43 biopsies (27%) and interpreted according to the cause of the LT and the associated lesions suggestive of PBC recurrence or evolution towards CR. Thus, we considered that bile duct loss was related to PBC recurrence in 11 cases and to CR in 31 cases (20%) (20 early and 11 late CR). In 1 case, the diagnosis was uncertain between CR and PSC recurrence.
Biopsies were strictly normal in 11 cases. Minimal lesions were observed (portal inflammation, lobular inflammation without necrosis, steatosis < 5%) in 24 cases. So, we considered that the liver was subnormal in 35 cases (22%). The liver functional tests were normal in 25 of the 35 cases. The patients have been transplanted for HBV (4), HDV (11), HCV (2) cirrhosis, PBC (5), FH(7), AIH (4), PSC (2) and 9 miscellaneous diseases. Acquired HCV infection was present in 8 of the normal cases.
However, 4 additional cases had acquired liver lesions (1 breast metastatic tumor, 2 nodular regenerative hyperplasia and 1 biliary obstruction).
Conclusion
In the study period, the acquired HCV liver infection was present in 39% of the cases (8 normal livers and 53 CH). Since routine HCV testing of blood products, the risk of HCV infection of the graft has currently disappeared. The recurrence of the primary liver disease (25%) and evolution to CR (20%) remain the two main complications of the long term follow-up. After 10 years the graft is near normal in 22% of the cases. The clinical evolution and the 15 year biopsies will allow us to evaluate the minimal abnormalities observed in normal 10 year liver biopsies. These results suggest the interest of performing liver biopsies at 10 years after transplantation.