The SPLIT Research Agenda 2013

This review focuses on active clinical research in pediatric liver transplantation with special emphasis on areas that could benefit from studies utilizing the SPLIT infrastructure and data repository. Ideas were solicited by members of the SPLIT Research Committee and sections were drafted by members of the committee with expertise in those given areas. This review is intended to highlight priorities for clinical research that could successfully be conducted through the SPLIT collaborative and would have significant impact in pediatric liver transplantation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98814/1/petr12090.pd

Variceal Hemorrhage and Adverse Liver Outcomes in Patients With Cystic Fibrosis Cirrhosis

OBJECTIVES: Cirrhosis occurs in 5% to 10% of cystic fibrosis (CF) patients, often accompanied by portal hypertension. We analyzed 3 adverse liver outcomes, variceal bleeding (VB), liver transplant (LT), and liver-related death (LD), and risk factors for these in CF Foundation Patient Registry subjects with reported cirrhosis. METHODS: We determined 10-year incidence rates for VB, LT, LD, and all-cause mortality (ACM), and examined risk factors using competing risk models and Cox-proportional hazard regression. RESULTS: From 2003 to 2012, 943 participants (41% females, mean age 18.1 years) had newly reported cirrhosis; 24.7% required insulin, 85% had previous pseudomonas. Seventy-three subjects had reported VB: 38 with first VB and new cirrhosis reported simultaneously and 35 with VB after cirrhosis report. Ten-year cumulative VB, LT, and LD rates were 6.6% (95% confidence interval [CI]: 4.0, 9.1%), 9.9% (95% CI: 6.6%, 13.2%), and 6.9% (95% CI: 4.0%, 9.8%), respectively, with an ACM of 39.2% (95% CI: 30.8, 36.6%). ACM was not increased in subjects with VB compared to those without (hazard ratio [HR] 1.10, 95% CI: 0.59, 2.08). CF-related diabetes (HR: 3.141, 95% CI:1.56, 6.34) and VB (HR: 4.837, 95% CI: 2.33, 10.0) were associated with higher LT risk, whereas only worse lung function was associated with increased LD in multivariate analysis. Death rate among subjects with VB was 24% with LT and 20.4% with native liver. CONCLUSIONS: VB is an uncommon complication of CF cirrhosis and can herald the diagnosis, but does not affect ACM. Adverse liver outcomes and ACM are frequent by 10 years after cirrhosis report

Basiliximab in pediatric liver transplantation: A pharmacokinetic-derived dosing algorithm

The pharmacokinetics and immunodynamics of basiliximab were assessed in 37 pediatric de novo liver allograft recipients to rationally design a dose regimen for this age-group. In part one of the study, patients were given 12 mg/m 2 basiliximab by bolus intravenous injection after organ perfusion and on day 4 after transplant. An interim pharmacokinetic evaluation supported a fixed-dose approach for part two of the study in which infants and children received two 10-mg doses of basiliximab and adolescents received two 20-mg doses. Blood samples were collected over a 12-week period for screening for anti-idiotype antibodies and analysis of basiliximab and soluble interleukin-2 receptor (IL-2R) concentrations. Basiliximab clearance in infants and children  5 L of ascites fluid drainage tended to have lower systemic exposure to basiliximab. CD25-saturating basiliximab concentrations were maintained for 27 ± 9 days in part one of the study (mg/m 2 dosing) with infants exhibiting the lowest durations. CD25 saturation lasted 37 ± 11 days in part two of the study, based on the fixed-dose regimen (p = 0.004 vs. mg/mg 2 dosing), but did not show the age-related bias observed in part one of the study. Anti-idiotype antibodies were detected in four patients, but this did not influence the clearance of basiliximab or duration of CD25 saturation. All 40 enrolled patients were included in the intent-to-treat clinical analysis. Episodes of acute rejection occurred in 22 patients (55%) during the first 12 months post-transplant. Three patients experienced loss of their graft as a result of technical complications, and six patients died during the 12-month study. Basiliximab was well tolerated by intravenous bolus injection, with no cytokine-release syndrome or other infusion-related adverse events. Hence, basiliximab was safe and well tolerated in pediatric patients undergoing orthotopic liver transplantation. To achieve similar basiliximab exposure as is efficacious in adults, pediatric patients < 35 kg in weight should receive two 10-mg doses and those ≥ 35 kg should receive two 20-mg doses of basiliximab by intravenous infusion or bolus injection. The first dose should be given within 6 h after organ perfusion and the second on day 4 after transplantation. A supplemental dose may be considered for patients with a large volume of drained ascites fluid relative to body size.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72080/1/j.1399-3046.2002.01086.x.pd

Pediatric Health-Related Quality of Life: Feasibility, Reliability and Validity of the PedsQL™ Transplant Module

The measurement properties of the newly developed Pediatric Quality of Life Inventory™ (PedsQL™) 3.0 Transplant Module in pediatric solid organ transplant recipients were evaluated. Participants included pediatric recipients of liver, kidney, heart and small bowel transplantation who were cared for at seven medical centers across the United States and their parents. Three hundred and thirty-eight parents of children ages 2–18 and 274 children ages 5–18 completed both the PedsQL™ 4.0 Generic Core Scales and the Transplant Module. Findings suggest that child self-report and parent proxy-report scales on the Transplant Module demonstrated excellent reliability (total scale score for child self-report α= 0.93; total scale score for parent proxy-report α= 0.94). Transplant-specific symptoms or problems were significantly correlated with lower generic HRQOL, supporting construct validity. Children with solid organ transplants and their parents reported statistically significant lower generic HRQOL than healthy children. Parent and child reports showed moderate to good agreement across the scales. In conclusion, the PedsQL™ Transplant Module demonstrated excellent initial feasibility, reliability and construct validity in pediatric patients with solid organ transplants.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79306/1/j.1600-6143.2010.03149.x.pd

Identification of PKD1L1 Gene Variants in Children with the Biliary Atresia Splenic Malformation Syndrome

Biliary atresia (BA) is the most common cause of end‐stage liver disease in children and the primary indication for pediatric liver transplantation, yet underlying etiologies remain unknown. Approximately 10% of infants affected by BA exhibit various laterality defects (heterotaxy) including splenic abnormalities and complex cardiac malformations — a distinctive subgroup commonly referred to as the biliary atresia splenic malformation (BASM) syndrome. We hypothesized that genetic factors linking laterality features with the etiopathogenesis of BA in BASM patients could be identified through whole exome sequencing (WES) of an affected cohort. DNA specimens from 67 BASM subjects, including 58 patient‐parent trios, from the NIDDK‐supported Childhood Liver Disease Research Network (ChiLDReN) underwent WES. Candidate gene variants derived from a pre‐specified set of 2,016 genes associated with ciliary dysgenesis and/or dysfunction or cholestasis were prioritized according to pathogenicity, population frequency, and mode of inheritance. Five BASM subjects harbored rare and potentially deleterious bi‐allelic variants in polycystin 1‐like 1, PKD1L1, a gene associated with ciliary calcium signaling and embryonic laterality determination in fish, mice and humans. Heterozygous PKD1L1 variants were found in 3 additional subjects. Immunohistochemical analysis of liver from the one BASM subject available revealed decreased PKD1L1 expression in bile duct epithelium when compared to normal livers and livers affected by other non‐cholestatic diseases. Conclusion WES identified bi‐allelic and heterozygous PKD1L1 variants of interest in 8 BASM subjects from the ChiLDReN dataset. The dual roles for PKD1L1 in laterality determination and ciliary function suggest that PKD1L1 is a new, biologically plausible, cholangiocyte‐expressed candidate gene for the BASM syndrome

Baseline ultrasound and clinical correlates in children with cystic fibrosis.

Objective: To investigate the relationship between abdominal ultrasound (US) findings and demographic, historical and clinical features in children with CF. Study design: Children age 3-12 years with CF without known cirrhosis, were enrolled in a prospective, multi-center study of US to predict hepatic fibrosis. Consensus US patterns were assigned by 3 radiologists as normal, heterogeneous, homogeneous, or cirrhosis. Data were derived from direct collection and U.S. or Toronto CF registries. Chi-square or ANOVA were used to compare variables among US groups and between normal and abnormal. Logistic regression was used to study risk factors for having abnormal US. Results: Findings in 719 subjects were normal (n=590, 82.1%), heterogeneous (64, 8.9%), homogeneous (41, 5.7%), and cirrhosis (24, 3.3%). Cirrhosis (p=0.0004), homogeneous (p<0.0001) and heterogeneous (p=0.03) were older than normal. More males were heterogeneous (p=0.001). More heterogeneous (15.0%, p=0.009) and cirrhosis (25.0%, p=0.005) ha

Neurodevelopmental Outcome of Young Children with Biliary Atresia and Native Liver: Results from the ChiLDReN Study

OBJECTIVES: To assess neurodevelopmental outcomes among participants with biliary atresia with their native liver at ages 12 months (group 1) and 24 months (group 2), and to evaluate variables predictive of neurodevelopmental impairment. STUDY DESIGN: Participants enrolled in a prospective, longitudinal, multicenter study underwent neurodevelopmental testing with either the Bayley Scales of Infant Development, 2nd edition, or Bayley Scales of Infant and Toddler Development, 3rd edition. Scores (normative mean = 100 ± 15) were categorized as ≥100, 85-99, and <85 for χ2 analysis. Risk for neurodevelopmental impairment (defined as ≥1 score of <85 on the Bayley Scales of Infant Development, 2nd edition, or Bayley Scales of Infant and Toddler Development, 3rd edition, scales) was analyzed using logistic regression. RESULTS: There were 148 children who completed 217 Bayley Scales of Infant and Toddler Development, 3rd edition, examinations (group 1, n = 132; group 2, n = 85). Neurodevelopmental score distributions significantly shifted downward compared with test norms at 1 and 2 years of age. Multivariate analysis identified ascites (OR, 3.17; P = .01) and low length z-scores at time of testing (OR, 0.70; P < .04) as risk factors for physical/motor impairment; low weight z-score (OR, 0.57; P = .001) and ascites (OR, 2.89; P = .01) for mental/cognitive/language impairment at 1 year of age. An unsuccessful hepatoportoenterostomy was predictive of both physical/motor (OR, 4.88; P < .02) and mental/cognitive/language impairment (OR, 4.76; P = .02) at 2 years of age. CONCLUSION: Participants with biliary atresia surviving with native livers after hepatoportoenterostomy are at increased risk for neurodevelopmental delays at 12 and 24 months of age. Those with unsuccessful hepatoportoenterostomy are >4 times more likely to have neurodevelopmental impairment compared with those with successful hepatoportoenterostomy. Growth delays and/or complications indicating advanced liver disease should alert clinicians to the risk for neurodevelopmental delays, and expedite appropriate interventions

Outcomes of Childhood Cholestasis in Alagille Syndrome: Results of a Multicenter Observational Study

Alagille syndrome (ALGS) is an autosomal dominant multisystem disorder with cholestasis as a defining clinical feature. We sought to characterize hepatic outcomes in a molecularly defined cohort of children with ALGS‐related cholestasis. Two hundred and ninety‐three participants with ALGS with native liver were enrolled. Participants entered the study at different ages and data were collected retrospectively prior to enrollment, and prospectively during the study course. Genetic analysis in 206 revealed JAGGED1 mutations in 91% and NOTCH2 mutations in 4%. Growth was impaired with mean height and weight z‐scores of <−1.0 at all ages. Regression analysis revealed that every 10 mg/dL increase in total bilirubin was associated with a decrease in height z‐score by 0.10 (P = 0.03) and weight z‐score by 0.15 (P = 0.007). Total bilirubin was higher for younger participants (P = 0.03) with a median of 6.9 mg/dL for those less than 1 year old compared with a median of 1.3 mg/dL for participants 13 years or older. The median gamma glutamyl transferase also dropped from 612 to 268 in the same age groups. After adjusting for age, there was substantial within‐individual variation of alanine aminotransferase. By 20 years of age, 40% of participants had developed definite portal hypertension. Estimated liver transplant–free survival at the age of 18.5 years was 24%. Conclusions: This is the largest multicenter natural history study of cholestasis in ALGS, demonstrating a previously underappreciated burden of liver disease with early profound cholestasis, a second wave of portal hypertension later in childhood, and less than 25% of patients reaching young adulthood with their native liver. These findings will promote optimization of ALGS management and development of clinically relevant endpoints for future therapeutic trials

Heterogeneous Liver on Research Ultrasound Identifies Children with Cystic Fibrosis at High Risk of Advanced Liver Disease: Interim Results of a Prospective Observational Case-Controlled Study

Objective: To assess if a heterogeneous pattern on research liver ultrasound examination can identify children at risk for advanced cystic fibrosis (CF) liver disease. Study design: Planned 4-year interim analysis of a 9-year multicenter, case-controlled cohort study (Prospective Study of Ultrasound to Predict Hepatic Cirrhosis in CF). Children with pancreatic insufficient CF aged 3-12 years without known cirrhosis, Burkholderia species infection, or short bowel syndrome underwent a screening research ultrasound examination. Participants with a heterogeneous liver ultrasound pattern were matched (by age, Pseudomonas infection status, and center) 1:2 with participants with a normal pattern. Clinical status and laboratory data were obtained annually and research ultrasound examinations biannually. The primary end point was the development of a nodular research ultrasound pattern, a surrogate for advanced CF liver disease. Results: There were 722 participants who underwent screening research ultrasound examination, of which 65 were heterogeneous liver ultrasound pattern and 592 normal liver ultrasound pattern. The final cohort included 55 participants with a heterogeneous liver ultrasound pattern and 116 participants with a normal liver ultrasound pattern. All participants with at least 1 follow-up research ultrasound were included. There were no differences in age or sex between groups at entry. Alanine aminotransferase (42 ± 22 U/L vs 32 ± 19 U/L; P = .0033), gamma glutamyl transpeptidase (36 ± 34 U/L vs 15 ± 8 U/L; P < .001), and aspartate aminotransferase to platelet ratio index (0.7 ± 0.5 vs 0.4 ± 0.2; P < .0001) were higher in participants with a heterogeneous liver ultrasound pattern compared with participants with a normal liver ultrasound pattern. Participants with a heterogeneous liver ultrasound pattern had a 9.1-fold increased incidence (95% CI, 2.7-30.8; P = .0004) of nodular pattern vs a normal liver ultrasound pattern (23% in heterogeneous liver ultrasound pattern vs 2.6% in normal liver ultrasound pattern). Conclusions: Research liver ultrasound examinations can identify children with CF at increased risk for developing advanced CF liver disease

Association Between Transient Elastography and Controlled Attenuated Parameter and Liver Ultrasound in Children With Cystic Fibrosis

Methods to identify children with cystic fibrosis (CF) at risk for development of advanced liver disease are lacking. We aim to determine the association between liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) with research ultrasound (US) patterns and conventional hepatic markers as a potential means to follow liver disease progression in children with CF. ELASTIC (Longitudinal Assessment of Transient Elastography in CF) is a nested cohort of 141 patients, ages 7-21, enrolled in the Prediction by US of Risk of Hepatic Cirrhosis in CF (PUSH) Study. We studied the association between LSM with research-grade US patterns (normal [NL], heterogeneous [HTG], homogeneous [HMG], or nodular [NOD]) and conventional hepatic markers. In a subgroup (n = 79), the association between controlled attenuation parameter (CAP) and US pattern was explored. Among 133 subjects undergoing VCTE, NOD participants (n = 26) had a significantly higher median (interquartile range) LSM of 9.1 kPa (6.3, 15.8) versus NL (n = 72, 5.1 kPa [4.2, 7.0]; P < 0.0001), HMG (n = 17, 5.9 kPa [5.2, 7.8]; P = 0.0013), and HTG (n = 18, 6.1 kPa [4.7, 7.0]; P = 0.0008) participants. HMG participants (n = 14) had a significantly higher mean CAP (SD) (270.5 dB/m [61.1]) compared with NL (n = 40, 218.8 dB/m [46.5]; P = 0.0027), HTG (n = 10, 218.1 dB/m [60.7]; P = 0.044), and NOD (n = 15, 222.7 dB/m [56.4]; P = 0.041) participants. LSM had a negative correlation with platelet count (rs = − 0.28, P = 0.0071) and positive correlation with aspartate aminotransferase-to-platelet ratio index (rs = 0.38, P = 0.0002), Fibrosis-4 index (rs = 0.36, P = 0.0007), gamma-glutamyltransferase (GGT; rs = 0.35, P = 0.0017), GGT-to-platelet ratio (rs = 0.35, P = 0.003), and US spleen size z-score (rs = 0.27, P = 0.0073). Conclusion: VCTE is associated with US patterns and conventional markers in patients with liver disease with CF