Utilization of older deceased donors for pediatric liver transplant may negatively impact long-term survival

BACKGROUND

Multiple adult studies have investigated the role of older donors (ODs) in expanding the donor pool. However, the impact of donor age on pediatric liver transplantation (LT) has not been fully elucidated.

METHODS

UNOS database was used to identify pediatric (≤18 years) LTs performed in the United States during 2002-22. Donors ≥40 years at donation were classified as older donors (ODs). Propensity analysis was performed with 1:1 matching for potentially confounding variables.

RESULTS

A total of 10,024 pediatric liver transplantation (PLT) patients met inclusion criteria; 669 received liver grafts from ODs. Candidates receiving OD liver grafts were more likely to be transplanted for acute liver failure, have higher Model End-Stage Liver Disease/Pediatric End-Stage Liver Disease (MELD/PELD) scores at LT, listed as Status 1/1A at LT, and be in the intensive care unit (ICU) at time of LT (all p < 0.001). Kaplan-Meier (KM) analyses showed that recipients of OD grafts had worse patient and graft survival (p < 0.001) compared to recipients of younger donor (YD) grafts. KM analyses performed on candidates matched for acuity at LT revealed inferior patient and graft survival in recipients of deceased donor grafts (p < 0.001), but not living donor grafts (p > 0.1) from ODs. Cox regression analysis demonstrated that living donor LT, diagnosis of biliary atresia and first liver transplant were favorable predictors of recipient outcomes, whereas ICU stay before LT and transplantation during 2002-12 were unfavorable.

CONCLUSION

Livers from ODs were used for candidates with higher acuity. Pediatric recipients of livers from ODs had worse outcome compared to YDs; however, living donor LT from ODs had the least negative impact on recipient outcomes.

Patient-Reported Outcomes to Describe Global Health and Family Relationships in Pediatric Weight Management

Background: Patient-reported outcomes (PROs) can assess chronic health. The study aims were to pilot a survey through the PEDSnet Healthy Weight Network (HWN), collecting PROs in tertiary care pediatric weight management programs (PWMP) in the United States, and demonstrate that a 50% enrollment rate was feasible; describe PROs in this population; and explore the relationship between child/family characteristics and PROs. Methods: Participants included 12- to 18-year-old patients and parents of 5- to 18-year-olds receiving care at PWMP in eight HWN sites. Patient-Reported Outcomes Measurement Information System (PROMIS®) measures assessed global health (GH), fatigue, stress, and family relationships (FR). T-score cut points defined poor GH or FR or severe fatigue or stress. Generalized estimating equations explored relationships between patient/family characteristics and PROMIS measures. Results: Overall, 63% of eligible parents and 52% of eligible children enrolled. Seven sites achieved the goal enrollment for parents and four for children. Participants included 1447 children. By self-report, 44.6% reported poor GH, 8.6% poor FR, 9.3% severe fatigue, and 7.6% severe stress. Multiple-parent household was associated with lower odds of poor GH by parent proxy report [adjusted odds ratio (aOR) 0.69, 95% confidence interval (CI) 0.55-0.88] and poor FR by self-report (aOR 0.36, 95% CI 0.17-0.74). Parents were significantly more likely to report that the child had poor GH and poor FR when a child had multiple households. Conclusions: PROs were feasibly assessed across the HWN, although implementation varied by site. Nearly half of the children seeking care in PWMP reported poor GH, and family context may play a role. Future work may build on this pilot to show how PROs can inform clinical care in PWMP.

Long-term follow-up and liver outcomes in children with cystic fibrosis and nodular liver on ultrasound in a multi-center study

BACKGROUND

Nodular liver (NOD) in cystic fibrosis (CF) suggests advanced CF liver disease (aCFLD); little is known about progression of liver disease (LD) after detection of sonographic NOD.

METHODS

Clinical, laboratory, and ultrasound (US) data from Prediction by Ultrasound of the Risk of Hepatic Cirrhosis in CFLD Study participants with NOD at screening or follow-up were compared with normal (NL). Linear mixed effects models were used for risk factors for LD progression and Kaplan-Meier estimator for time-to-event.

RESULTS

54 children with NOD (22 screening, 32 follow-up) and 112 NL were evaluated. Baseline (BL) and trajectory of forced expiratory volume, forced vital capacity, height/BMI z-scores were similar in NOD vs NL. Platelets were lower in NOD at BL (250 vs 331×10³/microL; p < 0.001) and decreased by 8600/year vs 2500 in NL. Mean AST to Platelet Ratio Index (1.1 vs 0.4; p < 0.001), Fibrosis-4 Index (0.4 vs 0.2, p < 0.001), and spleen size z-score (SSZ) [1.5 vs 0.02; p < 0.001] were higher in NOD at BL; SSZ increased by 0.5 unit/year in NOD vs 0.1 unit/year in NL. Median liver stiffness (LSM) by transient elastography was higher in NOD (8.2 kPa, IQR 6-11.8) vs NL (5.3, 4.2-7, p < 0.0001). Over 6.3 years follow-up (1.3-10.3), 6 NOD had esophageal varices (cumulative incidence in 10 years: 20%; 95% CI: 0.0%, 40.0%), 2 had variceal bleeding, and 2 underwent liver transplantation; none had ascites or hepatic encephalopathy. No NL experienced liver-related events.

CONCLUSIONS

NOD developed clinically evident portal hypertension faster than NL without worse growth or lung disease.

Predictors of survival following liver transplantation for pediatric hepatoblastoma and hepatocellular carcinoma: Experience from the Society of Pediatric Liver Transplantation (SPLIT)

Management of unresectable pediatric hepatoblastoma (HB) and hepatocellular carcinoma (HCC) remains challenging. The Society of Pediatric Liver Transplantation (SPLIT) database was used to study survival predictors in pediatric liver transplantation (LT) for HB and HCC. Event-free survival (EFS), associated risk factors, and postoperative complications were studied in children requiring LT for HB/HCC at 16 SPLIT centers. Three-year EFS was 81% for HB (n = 157) and 62% for HCC (n = 18) transplants. Of HB transplants, 6.9% were PRETEXT II and 15.3% were POST-TEXT I/II. Tumor extent did not impact survival (p = NS). Salvage (n = 13) and primary HB transplants had similar 3-year EFS (62% versus 78%, p = NS). Among HCC transplants, 3-year EFS was poorer in older patients (38% in ≥8-year-olds vs 86% <8-year-olds) and those with larger tumors (48% for those beyond versus 83% within Milan criteria, p = NS). Risk of infection (HR 1.5, 95% CI 1.1-2.2, p = .02) and renal injury (HR 2.4, 95% CI 1.7-3.3, p < .001) were higher in malignant versus nonmalignant LT. Survival is favorable for pediatric HB and HCC LT, including outcomes after salvage transplant. Unexpected numbers of LTs occurred in PRE/POST-TEXT I/II tumors. Judicious patient selection is critical to distinguish tumors that are potentially resectable; simultaneously, we must advocate for patients with unresectable malignancies to receive organs.

A clinical model to predict fibrosis on liver biopsy in paediatric subjects with nonalcoholic fatty liver disease

The incidence of nonalcoholic fatty liver disease (NAFLD) in children is rapidly increasing. Liver fibrosis is a poor prognostic feature that independently predicts cirrhosis. The time that intercedes the first medical encounter and biopsy is rate-limiting to multi-modal treatment. This study aimed to identify non-invasive parameters to predict advanced NAFLD and fibrosis. We conducted a single-center, retrospective 10-year analysis of 640 paediatric patients who underwent liver biopsy. 55 patients, age 3-21 years, had biopsy-confirmed NAFLD. We assessed primary outcomes, NAFLD activity score (NAS) and fibrosis scores, against non-invasive parameters by linear regression, by using binary cutoff values, and by a multivariate logistic regression fibrosis prediction model. NAS correlated with platelets and female sex. Fibrosis scores correlated with platelet counts, gamma glutamyl transferase (GGT), and ultrasound shear wave velocity. 25-hydroxy-vitamin D and GGT differentiated mild versus moderate-to-advanced fibrosis. Our multivariate logistical regression model-based scoring system predicted F2 or higher (parameters: BMI%, vitamin D, platelets, GGT), with sensitivity and specificity of 0.83 and 0.95 (area under the ROC curve, 0.944). We identify a clinical model to identify high-risk patients for expedited biopsy. Stratifying patients to abbreviate time-to-biopsy can attenuate delays in aggressive therapy for high-risk patients.

Clinicopathologic Characteristics of Centrilobular Injury in Pediatric Liver Transplantation

Centrilobular injury (CLI) is defined as the presence of perivenular mononuclear inflammation, hepatocyte dropout, and extravasated erythrocytes. In pediatric liver allografts, CLI has been associated with advanced fibrosis and chronic rejection (CR). We sought to better characterize the clinicopathologic features of CLI in the setting of T cell-mediated rejection (TCMR) and its association with complement component 4d (C4d) deposition. A total of 206 posttransplant pediatric patients (491 allograft liver biopsies) were available from 2000 to 2018, of which 63 patients (102 biopsies) showed evidence of TCMR and were included in the study. Of the patients, 35 (55.6%) had CLI on their initial episode of TCMR; those patients with CLI were significantly associated with the type of immunosuppression treatment (P = 0.03), severity of TCMR (P < 0.001), higher gamma-glutamyltransferase (P = 0.01), and advanced fibrosis (P = 0.03). There was a trend to shorter time interval from transplantation to presentation of CLI compared with those without CLI (P = 0.06). No difference was observed in graft or overall survival in the patients with CLI. In 20 patients with CLI, additional biopsies were available; in 45% of these patients, CLI was a persistent/recurrent finding. C4d deposition was noted in 12% of all biopsies (6 patients) with CLI. No significant correlation was noted in C4d deposition and CLI, CR, or graft/overall survival. In conclusion, CLI, although not significantly associated with worse graft survival, was significantly associated with severe TCMR and degree of fibrosis, which highlights the importance of active clinical management and follow-up for these patients.

Genetic ablation or chemical inhibition of phosphatidylcholine transfer protein attenuates diet-induced hepatic glucose production

Phosphatidylcholine transfer protein (PC-TP, synonym StARD2) is a highly specific intracellular lipid binding protein that is enriched in liver. Coding region polymorphisms in both humans and mice appear to confer protection against measures of insulin resistance. The current study was designed to test the hypotheses that Pctp-/- mice are protected against diet-induced increases in hepatic glucose production and that small molecule inhibition of PC-TP recapitulates this phenotype. Pctp-/- and wildtype mice were subjected to high-fat feeding and rates of hepatic glucose production and glucose clearance were quantified by hyperinsulinemic euglycemic clamp studies and pyruvate tolerance tests. These studies revealed that high-fat diet-induced increases in hepatic glucose production were markedly attenuated in Pctp-/- mice. Small molecule inhibitors of PC-TP were synthesized and their potencies, as well as mechanism of inhibition, were characterized in vitro. An optimized inhibitor was administered to high-fat-fed mice and used to explore effects on insulin signaling in cell culture systems. Small molecule inhibitors bound PC-TP, displaced phosphatidylcholines from the lipid binding site, and increased the thermal stability of the protein. Administration of the optimized inhibitor to wildtype mice attenuated hepatic glucose production associated with high-fat feeding, but had no activity in Pctp-/- mice. Indicative of a mechanism for reducing glucose intolerance that is distinct from commonly utilized insulin-sensitizing agents, the inhibitor promoted insulin-independent phosphorylation of key insulin signaling molecules.

CONCLUSION

These findings suggest PC-TP inhibition as a novel therapeutic strategy in the management of hepatic insulin resistance.