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M Colledan

Publications and source records attributed to M Colledan.

At least 19 recordsLinked to original sources

Liberal policy of split liver for pediatric liver transplantation. A single centre experience.

We adopted a liberal policy of extensive use of split liver in a pediatric liver transplantation (LT) program. Over a 19-month period, we have performed 64 LT in 54 patients with pediatric indications. One patient received two liver grafts as a part of a liver-small bowel transplantation and was not considered. Of the 60 LT considered, performed in 53 patients, 34 were with split grafts. The 1-year actuarial survival for the patients transplanted with a split graft was 81% and 89% when only elective cases were considered. The median time on the waiting list was 22 days with no mortality. The extensive use of split liver allowed transplantation in a large number of pediatric patients, with good results without the need for living donor liver transplantation. We envisage a trend towards systematic splitting of liver grafts.

Actuarial Analysis↗

Rejection and tacrolimus conversion therapy in paediatric liver transplantation.

Rejection and efficacy of rescue therapy with tacrolimus were evaluated in 50 children who underwent primary, ABO-compatible, liver transplantation. Six patients who died within the first week and one child who underwent retransplantation from an ABO-incompatible donor were excluded from the study. No patient or graft were lost due to rejection. We observed 48 episodes of rejection in 33 patients. Fourteen patients required conversion to tacrolimus for steroid-resistant rejection with resolution of rejection. One of these children developed PTLD. Other indications for conversion were neurotoxicity and hirsutism. One patient developed blindness of unknown origin after the conversion. Other side effects of tacrolimus were minor and resolved by lowering the dose. Five patients developed rejection after conversion; all achieved resolution with either steroid therapy or increase of tacrolimus dose. In conclusion, our study confirms that tacrolimus is an effective rescue therapy for paediatric liver transplantation.

ABO Blood-Group System↗

Circulating Epstein-Barr virus DNA to monitor lymphoproliferative disease following pediatric liver transplantation.

Epstein-Barr virus (EBV) infection can induce uncontrolled lymphocyte B proliferation in immunosuppressed transplant patients. Monitoring circulating EBV-infected lymphocytes can help in identifying patients at risk of posttransplant lymphoproliferative disease (PTLD). Circulating EBV genome levels were determined in 54 liver transplant pediatric recipients. Ten patients had more than 500 EBV genome/10(5) peripheral blood lymphocytes (PBL) and exhibited clinical manifestations of EBV infection; three developed PTLD. To treat EBV infection, the level of immunosuppression was reduced and acute rejection developed in 4 patients. Three were treated with steroid and one had to be switched from cyclosporine to tacrolimus. Treatment of acute rejection was associated with increases in circulating EBV genome. None of the patients with less than 500 EBV genome/10(5) PBL developed PTLD or EBV infection. Monitoring of EBV DNA is useful in the management of EBV infection and PTLD following pediatric liver transplantation. EBV infection should be treated in ways which do not expose patients to the risk of rejection.

Adolescent↗

Extensive use of split liver for pediatric liver transplantation: a single-center experience.

The results of the extensive use of in situ liver splitting in a pediatric liver transplant program are presented. All referred donors were considered for split liver, and when the donor-recipient body weight ratio (DRWR) was greater than 2, the grafts were split. A modified split-liver technique was adopted when the DRWR was 2 or less. Eighty liver procurements were attempted and 72 (90%) were performed, enabling 65 children to receive 42 split, 22 whole, and 8 reduced-size livers. The right portions of the grafts were transplanted by other centers into adults. Median patient waiting time was 22 days, with no mortality on the waiting list. After a median follow-up of 14 months, overall patient and graft survival rates were 85% and 81%, respectively. Fifty-eight children received a single allograft, whereas 7 children required retransplantation. Two-year actuarial survival rates were 85% for split-liver recipients, 84% for whole-liver recipients, and 67% for reduced-size liver recipients. Vascular complications developed in 18% of the patients, with no difference among the 3 groups with different technique. Biliary complications developed in 25% of the children, mainly in reduced-size and split-liver recipients. Patient and graft survival rates for right split-liver grafts were 84% and 79%, respectively. Adopting a liberal policy of liver splitting provides allografts of optimal quality for pediatric transplantation, allowing a dramatic decrease in the waiting list time. The in situ split-liver technique should be considered the method of choice for expanding the cadaveric liver donor pool.

Adolescent↗

Post-hepatitis primary disease does not influence 6-year survival after liver transplantation beyond 1 year.

Orthotopic liver transplantation (OLT) is used as a definitive treatment for end-stage liver disease and prolonged posttransplant survival has already been reported. The incidence of late mortality and graft morbidity is, however, not well defined and the role of primary viral disease in the long-term follow-up results is not clear. Data of posttransplant follow-up in 213 patients, 156 adults and 57 children, who survived at least 1 year were reviewed in order to define causes of graft dysfunction, graft loss and death. In 98 patients, 103 persistent graft dysfunctions were found. Thirty-four grafts were later lost [28 deaths and 6 successful retransplantations (re-OLT)]. The results were reviewed grouping patients according to their age and viral hepatitis status at the time of the transplantation. HBV-positive patients (51) showed 4 re-OLT (1 HBV), 3 liver-related deaths (2 HBV), 24 graft dysfunctions (8 HBV, 5 HCV), and 85.2% 6-year survival (based on 100% survival at 1 year). HCV-positive adults (28) showed 1 re-OLT, 3 HCV-related deaths, 24 graft dysfunctions (19 HCV), and 68.8% 6-year survival. HBV-HCV-positive patients (14) showed no graft loss and death, 10 graft dysfunctions (7 HCV, 1 HBV, 2 HBV-HCV), and 81.8% 6-year survival. HBV-HCV-negative adults (63) showed 3 non-hepatitis-related re-OLT, 5 liver-related deaths (2 HCV), 24 graft dysfunctions (6 HCV, 2 HBV), and 83.1% 6-year survival. HBV-HCV-negative children (49) showed no re-OLT, 1 HCV-related death, 14 graft dysfunctions (3 HCV), and 92.6% 6-year survival. HCV-positive children (8) showed 1 HCV-related re-OLT, 2 HCV-related deaths, 4 graft dysfunctions (3 HCV), and 81.3% 6-year survival. The main cause of graft dysfunction was hepatitis (45 HCV and 13 HBV), followed by technical complications (21), rejection (16), recurrent alcoholism (3), HIV infection (1), and unknown causes (4). In this long-term post-transplant follow-up series, viral hepatitis led to graft dysfunction in 58/103 (56.3%) cases, late graft failure was viral hepatitis-related in 11/ 20 (55%) cases, and, as a total, HCV infection was present in 45/58 (77.5%) cases of viral hepatitis-related graft damage. Looking at the timing of hepatitis-related graft failure, in 70% of cases death occurred after the 5th post-transplant year. In our experience, the occurrence of hepatitis, particularly HCV induced, was common and led to abnormal graft function, but the 6-year post-transplant survival (based on 100% survival at 1 year) in patients surviving for at least 1 year did not differ on the basis of the pretransplant viral hepatitis status. This finding may be consistent with the slow progression of the viral damage and longer follow-up results remain to be established. Nevertheless, data from the present study suggest that in long-term liver transplant survivors, the risk of deteriorating liver damage and eventual failure after 5 years remains only in those patients experiencing a viral hepatitis infection.

Adolescent↗

Rescue FK506 early conversion for refractory rejection after pediatric liver transplantation: experience in 20 children.

Tacrolimus (FK506) is an effective and relatively safe novel immunosuppressant able to revert refractory rejection after pediatric liver transplantation (LTx). Between April 1993 and October 1996, 20 pediatric patients were converted to tacrolimus for biopsy-proven, steroid-resistant liver rejection. The mean follow-up was 18 months. The median time from LTx to switch was 20 days. Tacrolimus was administered per os at a mean dosage of 0.23 mg/kg per day to maintain median blood levels of 10.8 ng/ml at 1 week and 9.2 ng/ml at 1 year from the switch. Of the 20 patients, 15 are alive and they all recovered from rejection without the need of OKT3 after conversion. The major causes of death were: one multiorgan failure, two infections (cytomegalovirus Aspergillus), one bowel perforation, and one posttransplant lymphoproliferative disease. One patient experienced late side effects and was reconverted to cyclosporine when she was already rescued from hepatic allograft rejection. The results confirm that an earlier conversion to tacrolimus should be recommended after pediatric liver transplantation in order to revert hepatic allograft rejection with the best safety profile.

Child, Preschool↗

Hepatitis C virus genotypes and reinfection of the graft during long-term follow-up in 35 liver transplant recipients.

To understand the clinical outcome of hepatitis C virus (HCV) recurrence, data from 35 liver transplant recipients who survived more than 6 months were reviewed. The presence of HCV-RNA was evaluated and genotyping was performed. On the basis of alanine aminotransferase (ALT) levels, patients were sorted into four groups. In 20 patients, a chronic elevation in ALT was found; HCV-RNA detection was positive in 17/17 and the following genotypes were found in 15 of them: 1b in ten patients, 2a in four patients, and 3a in one patient. In 11 patients, ALT levels remained normal throughout follow-up; in nine of them HCV-RNA was positive; HCV genotyping was available in eight patients and identified type 1b in two, type 2a in five, and type 3a in another patient. In two patients, ALT fluctuated above and below the upper limits of normality; type 1b HCV-RNA was found in one of them. In two patients, after an initial period of normality, ALT levels showed an abrupt rise; HCV-RNA was positive and type 1b was identified in both patients. Eight patients developed HCV-related deep jaundice and three of them spontaneously recovered. Progressive hepatic injury occurred in eight patients, six with chronic ALT elevation and two showing a late ALT elevation; genotype 1b was present in seven patients while in one, genotype 3a was found; sub-acute graft failure developed in five of them, leading to death in two and retransplantation in the others; the other three patients are alive with recurrent overt cirrhosis. The 1, 3, and 5 year actuarial survivals were 89%, 79%, and 63% respectively. The 1, 3, and 5 year actuarial risks of progressive graft damage were 6%, 7%, and 15%, respectively. In conclusion, HCV reinfection causes a slow decrease in the long-term patients' survival. Persistent elevation of ALT is more frequently observed in patients with genotype 1b infection.

Adolescent↗

Paediatric liver transplantation in Italy.

The paediatric liver transplantation programme was started, at our institution, in 1988 and since then 75 children have received 79 transplants, which corresponds to about 85% of all the paediatric liver transplantations performed in Italy. The main indications to transplantation were biliary atresia, familiar cholangiopathies and metabolic diseases. The patients came from all the regions of Italy, except for 2 of them who came from abroad. Patients with malnutrition and impaired growth underwent an aggressive nutritional programme whilst waiting for transplantation. The transplants were performed using whole grafts, reduced size grafts and, recently, with grafts from split livers, in 7 cases. Immunosuppression was based on a double drug therapy with Cyclosporine and low dose steroids. Steroid resistant acute rejection was treated, with OKT3 until 1993 and with conversion from Cyclosporine to FK506, thereafter. Interventional radiology was most useful in treating biliary complications. The introduction of Gancyclovir greatly reduced the incidence and severity of cytomegavirus related complications. Three years survival after liver transplantation was 62% for children under 2 years of age and 78% for those between 2 and 15 years. These results do not differ substantially from those reported by the European Liver Transplant Registry.

Adolescent↗