The aim of our study was to retrospectively assess any correlation between graft fibrosis and selected immunological factors in pediatric liver transplant recipients. The study was performed on 33 patients after living related donor transplantation, divided into 2 groups depending on history of acute rejection episodes after transplantation. We assessed liver biopsies for presence of fibrosis, signs of antibody-mediated rejection, inflammatory infiltrations, and changes in bile ducts. We correlated these findings with assessment of anti-HLA antibodies. Among 14 patients with ACR, a history fibrosis was found in 8 patients (57%). In 19 patients without a history of ACR, fibrosis was found in 9 patients (47%). Anti-HLA antibodies were found in 47% of patients with fibrosis and in only 18.75% of patients without fibrosis. Among 3 patients with signs of antibody-mediated rejection, all had fibrosis in the graft 2 years after transplantation. We did not find any patient with chronic rejection or ductopenia. We suggest that there is a correlation between ACR and development of graft fibrosis present in liver grafts from recipients with normal liver biochemistry. Anti-HLA antibodies class II seems to be most important in development of fibrosis.

Background and rationale for the study. The aim of the study was to determine the prognostic value of histopathological findings with special care to the severity of liver fibrosis at the moment of hepatoportoenterostomy (HPE) in children with biliary atresia (BA). We performed analysis of 142 wedge liver biopsies taken at the time of HPE. All patients were operated by the same surgical team between 1995 and 2007. According to the outcome 6 months after HPE patients were divided into prognostic groups: group 1-bilirubin level < 2 mg% (n = 65), group 2-bilirubin level > 2 mg% (n = 77). Liver biopsies were re-evaluated according to the extended histopathological protocol and then were compared between the prognostic groups. Survival with native liver (SNL) estimates were performed in regard to severity of liver fibrosis. Survival with native liver estimates after 2, 5 and 10 years in patients after successful operation were 96%, 91%, 75% vs. 30%, 11%, and 5% if operation failed (p < 0.001). There was no difference between groups in the following variables: fibrosis (p = 0.69), portal inflammation (p = 0.99), lobular inflammation (p = 0.95), cholangiolitis (p = 0.23), accumulation of bile pigments (zone 1:p = 0.49; zone 2:p = 0.51; zone 3:p = 0.48), bile plugs in canaliculi (p = 0.12), bile plugs in ducts (p = 0.32), bilirubinostasis in hepatocytes (p = 0.45), bile ductular proliferation (p = 0.59), ductal plate malformation (p = 0.12), focal necrosis (p = 0.44), giant cell transformation (p = 0.45), haematopoesis (p = 0.52), ductopenia (p = 0.46), microabscesses (p = 0.49), ballooning of hepatocytes (p = 0.08). The actuarial 5/10-year SNL was not dependent on severity of liver fibrosis (log-rank test p = 0.84). The severity of fibrosis corresponded neither with the age at HPE nor with the laboratory findings before operation but increased the risk of portal hypertension. Liver histology at the time of HPE is of limited value in prognosis making in BA.

Introduction: Various congenital and acquired diseases of the lower urinary tract can lead to chronic renal failure requiring renal replacement therapy. Aim: The aim of the study was to assess problems and results of kidney transplantation in children with significant lower urinary tract dysfunction. Materials and Methods: Between 1984 and 2007, there were 33 kidney transplantations in children with end-stage renal disease and severe lower tract dysfunction out of 539 kidney transplantations performed in our department. The patients were 23 males and 10 females. Thirty patients received a kidney from a deceased donor, the remaining 3 from a living related donor. The age at transplantation ranged from 2.25 years to 19 years. In 26 patients an ileal conduit modo Bricker was created (in 21 patients at transplant operation). Bladder augmentation was performed in 6 patients and a continent urinary reservoir was created in 1. Results: Post-transplant follow-up ranged from 7 to 88 months (mean 32 months). Overall patient survival is 100% and graft survival is 97%. Creatinine concentrations ranged from 0.3 to 3.4 mg% (mean 0.92 mg%). Surgical complications were diagnosed in 16 patients. All surgical complications were treated successfully and none of them caused graft loss. Urinary tract infections (UTI) were the most commonly observed complication, occurring in 26/33 (78%) patients, but the majority of these UTI were asymptomatic and had no influence on graft function. Conclusions: Kidney transplantation in children with lower urinary tract dysfunction and end-stage renal failure offers excellent medium term results in our experience, despite the creation of non-standard urinary drainage. Recurrent urinary tract infections are the most common complications in these patients, but in the majority of cases this does not lead to impairment of graft function.

Antibody-mediated rejection (AMR), associated with the presence of C4d deposits, is well-defined in kidney transplantation but much less documented in liver transplantation (LTx). The aim of our study was to retrospectively analyze a group of pediatric liver transplant recipients who experienced episodes of acute rejection in the past, for the signs of AMR and its impact on liver histology. Our study population consisted of 18 patients after living related donor liver transplantation with a history of acute cellular rejection (1-5/patient). In all of them, actual liver function was good at almost 2-year median follow-up after transplantation. We reassessed all liver biopsies taken from these children between 5 days to 5.7 years after transplantation for signs of acute cellular rejection and antibody-mediated rejection. In all patients, anti-HLA antibodies were also assessed at least 2 years after transplantation (2.18-12.27 years, median 6.795 years). There were 27 episodes of acute rejection proved by liver biopsy. Signs of AMR were found in 6 of 18 patients (33.3%). In 5 of these patients, donor-specific (DSA) and non-specific anti-HLA antibodies were also identified. In the group of 12 patients with acute rejection without histochemical signs of AMR, anti-HLA antibodies were found in sera of only 5 of 12 patients after transplantation. Our study shows some correlation between C4d-positive reaction in liver biopsies with acute cellular rejection and presence of anti-HLA antibodies, particularly against HLA class II. We did not find any difference in the late graft function, which could be correlated with the presence of AMR. Further studies on larger groups of patients are necessary.

An increasing number of AB0-incompatible (AB0i) liver transplantations (LT) are being undertaken internationally in recent years due to organ shortages and the need for urgent transplantation. The aim of our study was establish the value of ABOi LT from available retrospective results of AB0i pediatric liver transplantations performed in European reference centers now belonging to the TransplantChild, European Reference Network (ERN). Data from medical records were analyzed, including demographic data, diagnosis, urgency of transplantation, time on the waiting list, PELD/MELD score, desensitization procedures, immunosuppression, selected post-transplant complications, and patient and graft survival. A total of 142 patients (pts) with transplants between 1986 and 2018 in 8 European transplant centers were included in the study. The indications for liver transplantation were: cholestatic diseases in 62 pts, acute liver failure in 42 pts, and other conditions in the remaining 38 pts. Sixty-six patients received grafts from living donors, and seventy-six received grafts from deceased donors. Both patient and graft survival were significantly affected by deceased donor type, urgent transplantation, and the development of vascular complications. In the multivariate analysis, vascular complications had a negative impact on patient and graft survival, while a longer time from the first AB0i LT in the study showed better results, suggesting an international learning experience. In conclusion, we believe that AB0i LT in children is now a safe procedure that may be adopted more readily in children.