Predictive factors for portal fibrosis in pediatric liver transplant recipients

Recent histopathological studies showed an unexpected high incidence of pathological changes in asymptomatic survivors after pediatric liver transplantation. The aim of this study was to analyze the occurrence of histological abnormalities, to assess the clinical significance, and to identify predictive factors for these pathological changes.

The first annual protocol graft biopsies of 84 consecutive liver transplants were analyzed and correlated with concomitant liver function tests. Identification of predictive factors for the histological abnormalities in the biopsies was performed by a multivariate logistic regression analysis.

The incidence of portal fibrosis (PF) was 31%. Liver function tests showed except for the albumin level, an increase in the PF group compared with the group without PF. Mean values of alkaline phosphatase and direct bilirubin were 264 U/liter and 3 micromol/liter, respectively, in the normal group, and 435 U/liter and 23 micromol/liter, respectively, in the PF group (P=0.043 and 0.037). Eight of 19 univariantly tested variables were entered into a logistic regression model: cold ischemia time, preservation solution, type of allograft, cytomegalovirus recipient status, type of biliary reconstruction, biliary complications, graft complications, and rejection. A significant positive correlation with PF was found for cold ischemia time, biliary complications, and cytomegalovirus status. Acute rejection showed a negative correlation.

The incidence of PF within 1 year post liver transplantation was 31%. This finding was accompanied by cholestatic liver function test abnormalities. Factors predisposing to PF were a prolonged cold ischemia time, biliary complications, and a positive cytomegalovirus recipient status. Acute rejection seemed to prevent for PF.