Kathleen Falkenstein

Absorption characteristics of a microemulsion formulation of cyclosporine in de novo pediatric liver transplant recipients.

In pediatric liver transplant recipients, oral cyclosporine (CsA) therapy may be complicated by impaired or delayed absorption during the initial weeks posttransplant. Neoral (NL) is a microemulsion preconcentrate formulation of CsA expected to increase the rate and extent of absorption of CsA and have less pharmacokinetic variability. The absolute bioavailability (F) of CsA from NL was compared with that of the currently marketed Sandimmune (SM) formulation in a double-blind, crossover study conducted in 9 pediatric liver transplant recipients (age 6 months to 11 years) between 8 and 20 days posttransplant. After determination of CsA pharmacokinetics for a steady-state intravenous dose, patients were randomized to receive a single oral dose of NL or SM in period I and the alternative formulation in period II. Clearance (Clt) and volume of distribution (Vss) values (mean +/- s.d.) calculated from the i.v. dose were similar to that previously reported for pediatric patients (Clt = 12.0 +/- 1.3 ml/min/kg; Vss = 2.2 +/- 0.2 L/kg). Mean F (+/- SD) for NL was significantly higher than SM (NL = 37.6 +/- 14.6%; SM = 24.7 +/- 8.0%; P = 0.05). Although not reaching statistical significance, the observed maximum blood concentration (Cmax) was higher, and the time to Cmax (Tmax) was shorter for NL in 8 or 9 patients. There were no significant correlations between age and any pharmacokinetic parameter for the group as a whole--however, there were statistically significant correlations between age and F for NL (r = 0.87; P = 0.02), and for age and Vss (r = 0.91; P = 0.01) for the 6 patients aged 2 years or less. In this pediatric liver transplant population, Neoral demonstrated improved absorption (% increase in F) compared to Sandimmune. In liver transplant recipients aged 2 years or less, absorption of Neoral may be a function of age and/or bowel length.

Living donor liver transplantation in critically ill children

Abstract: From December 1993, St Christopher’s Hospital for Children, Philadelphia, PA, USA has provided living donors the opportunity to donate a portion of their liver to children who are critically ill. This report evaluates the results of living donor liver transplants (LDLT) in critically ill children. We retrospectively reviewed the first 22 LDLT at our institution and compared the patient and graft survival of the nine critically ill children with the 13 stable children. Twenty‐two LDLT have been performed at our institution between December 1993 and October 1997. Nine of 22 transplants [United Network for Organ Sharing (UNOS) Status I] were performed in children who were critically ill. Thirteen of the LDLT (UNOS Status II and III) were performed on stable children either in the hospital or admitted electively from home. The median weight and age at the time of transplant were 7 kg (range 4.6–54.5 kg) and 16 months (range 3 months–12 yr), respectively, and there was no statistical difference between the two groups. In critically ill children the 1‐yr allograft and patient survival was 66% and 89%, respectively, exceeding the published results from UNOS for patients on life support (59.5% graft and 69.7% patient survival at 1 yr). One‐yr allograft and patient survival in the stable children was 92.3% and 100%, respectively. All living donors are alive and well with normal liver function. In conclusion, our results show that LDLT is a viable approach for transplantation in critically ill children with liver failure and should be offered to potential donors.

Pediatric Recipients of Three or More Hepatic Allografts: Results and Technical Challenges

BACKGROUND/PURPOSE Children who require a liver transplant at an early age risk chronic allograft rejection (CAR) and other causes of allograft loss. Multiple retransplants may be required for long-term patient survival. The authors evaluate this approach based on our results and technical difficulties. METHODS Charts of 7 children who received 3 or more liver transplants from 1989 to the present were reviewed retrospectively. RESULTS A total of 151 children required liver transplantation at our institution since 1989. Of these, 4 boys and 3 girls (mean age, 6.2 years; range, 3 to 14 years) have received 3 or more allografts. The etiology of liver failure for the penultimate allograft was CAR (n = 6) and hepatic artery thrombosis (HAT; n = 1). Five cases required modification of portal vein or hepatic artery anastomoses. Two patients with vena caval strictures required supradiaphragmatic vena caval reconstruction. The original Roux-en-Y limb was adequate for biliary reconstruction in all cases. Five children currently are alive (survival rate, 71%) with good graft function having had a mean follow-up of 23 months (range, 2 to 48 mos.). CONCLUSIONS The operative procedure for the multiple hepatic transplant child is challenging. The transplant team must be prepared for intraoperative issues such as extended organ ischemia time during hepatectomy, extensive blood loss, and potential need for creative organ revascularization techniques. Overall, multiple retransplant results are good and justify the use of multiple allografts.