Evaluation of pediatric patients for intestinal transplantation in the modern era.

OBJECTIVES: To review recent evaluations of pediatric patients with intestinal failure (IF) for intestinal transplantation (ITx), waiting list decisions, and outcomes of patients listed and not listed for ITx at our center. METHODS: Retrospective chart review of 97 patients evaluated for ITx from January 2014 to December 2021 including data from referring institutions and protocol laboratory testing, body imaging, endoscopy, and liver biopsy in selected cases. Survival analysis used Kaplan-Meier estimates and Cox proportional hazards regression. RESULTS: Patients were referred almost entirely from outside institutions, one-third because of intestinal failure-associated liver disease (IFALD), two-thirds because of repeated infective and non-IFALD complications under minimally successful intestinal rehabilitation, and a single patient because of lost central vein access. The majority had short bowel syndrome (SBS). Waiting list placement was offered to 67 (69%) patients, 40 of whom for IFALD. The IFALD group was generally younger and more likely to have SBS, have received more parenteral nutrition, have demonstrated more evidence of chronic inflammation and have inferior kidney function compared to those offered ITx for non-IFALD complications and those not listed. ITx was performed in 53 patients. Superior postevaluation survival was independently associated with higher serum creatinine (hazard ratio [HR] 15.410, p = 014), whereas inferior postevaluation survival was associated with ITx (HR 0.515, p = 0.035) and higher serum fibrinogen (HR 0.994, p = 0.005). CONCLUSIONS: Despite recent improvements in IF management, IFALD remains a prominent reason for ITx referral. Complications of IF inherent to ITx candidacy influence postevaluation and post-ITx survival.

Does High-Intensity Exercise Cause Acute Liver Injury in Patients with Fontan Circulation? A Prospective Pilot Study.

The Fontan procedure results in chronic hepatic congestion and Fontan-associated liver disease (FALD) characterized by progressive liver fibrosis and cirrhosis. Exercise is recommended in this population, but may accelerate the progression of FALD from abrupt elevations in central venous pressure. The aim of this study was to assess if acute liver injury occurs after high-intensity exercise in patients with Fontan physiology. Ten patients were enrolled. Nine had normal systolic ventricular function and one had an ejection fraction < 40%. During cardiopulmonary exercise testing, patients had near-infrared spectroscopy (NIRS) to measure oxygen saturation of multiple organs, including the liver, and underwent pre- and post-exercise testing with liver elastography, laboratory markers, and cytokines to assess liver injury. The hepatic and renal NIRS showed a statistically significant decrease in oxygenation during exercise, and the hepatic NIRS had the slowest recovery compared to renal, cerebral, and peripheral muscle NIRS. A clinically significant increase in shear wave velocity occurred after exercise testing only in the one patient with systolic dysfunction. There was a statistically significant, albeit trivial, increase in ALT and GGT after exercise. Fibrogenic cytokines traditionally associated with FALD did not increase significantly in our cohort; however, pro-inflammatory cytokines that predispose to fibrogenesis did significantly rise during exercise. Although patients with Fontan circulation demonstrated a significant reduction in hepatic tissue oxygenation based on NIRS saturations during exercise, there was no clinical evidence of acute increase in liver congestion or acute liver injury following high-intensity exercise.

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.

Recurrence of Primary Sclerosing Cholangitis After Liver Transplant in Children: An International Observational Study.

BACKGROUND AND AIMS: Recurrent primary sclerosing cholangitis (rPSC) following liver transplant (LT) has a negative impact on graft and patient survival; little is known about risk factors for rPSC or disease course in children. APPROACH AND RESULTS: We retrospectively evaluated risk factors for rPSC in 140 children from the Pediatric PSC Consortium, a multicenter international registry. Recipients underwent LT for PSC and had >90 days of follow-up. The primary outcome, rPSC, was defined using Graziadei criteria. Median follow-up after LT was 3 years (interquartile range 1.1-6.1). rPSC occurred in 36 children, representing 10% and 27% of the subjects at 2 years and 5 years following LT, respectively. Subjects with rPSC were younger at LT (12.9 vs. 16.2 years), had faster progression from PSC diagnosis to LT (2.5 vs. 4.1 years), and had higher alanine aminotransferase (112 vs. 66 IU/L) at LT (all P < 0.01). Inflammatory bowel disease was more prevalent in the rPSC group (86% vs. 66%; P = 0.025). After LT, rPSC subjects had more episodes of biopsy-proved acute rejection (mean 3 vs. 1; P < 0.001), and higher prevalence of steroid-refractory rejection (41% vs. 20%; P = 0.04). In those with rPSC, 43% developed complications of portal hypertension, were relisted for LT, or died within 2 years of the diagnosis. Mortality was higher in the rPSC group (11.1% vs. 2.9%; P = 0.05). CONCLUSIONS: The incidence of rPSC in this cohort was higher than previously reported, and was associated with increased morbidity and mortality. Patients with rPSC appeared to have a more aggressive, immune-reactive phenotype. These findings underscore the need to understand the immune mechanisms of rPSC, to lay the foundation for developing new therapies and improve outcomes in this challenging population.

Oral Vancomycin, Ursodeoxycholic Acid, or No Therapy for Pediatric Primary Sclerosing Cholangitis: A Matched Analysis.

BACKGROUND AND AIMS: Many children with primary sclerosing cholangitis (PSC) receive oral vancomycin therapy (OVT) or ursodeoxycholic acid (UDCA). There is a paucity of data on whether these medications improve outcomes. APPROACH AND RESULTS: We analyzed retrospective data from the Pediatric PSC Consortium. Children treated with OVT were matched 1:1:1 to those treated with UDCA or managed with observation (no treatment) based on the closest propensity score, ensuring similar baseline characteristics. Two hundred sixty-four patients (88 each with OVT, UDCA, or observation) had matching propensity scores and were similar in demographics, phenotype, immunosuppression, baseline biochemistry, and hepatic fibrosis. After 1 year in an intention-to-treat analysis, all outcome metrics were similar regardless of treatment group. In OVT, UDCA, and untreated groups, respectively: Gamma-glutamyltransferase normalized in 53%, 49%, and 52% (P = not significant [NS]), liver fibrosis stage was improved in 20%, 13%, and 18% and worsened in 11%, 29%, and 18% (P = NS), and the 5-year probability of liver transplant listing was 21%, 10%, and 12% (P = NS). Favorable outcome was associated with having a mild phenotype of PSC and minimal hepatic fibrosis. CONCLUSIONS: We presented the largest-ever description of outcomes on OVT in PSC and compared them to carefully matched patients on UDCA or no therapy. Neither OVT nor UDCA showed improvement in outcomes compared to a strategy of observation. Patients progressed to end-stage liver disease at similar rates. Spontaneous normalization of biochemistry is common in children receiving no therapy, particularly in the majority of children with a mild phenotype and an early stage of disease. Placebo-controlled treatment trials are needed to identify effective treatments for pediatric PSC.

Prevalence and Clinical Significance of Autoantibodies in Children with Overweight and Obesity with Nonalcoholic Fatty Liver Disease.

OBJECTIVES: To evaluate the prevalence and clinical significance of autoantibodies in children with overweight and obesity with nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) compared with those with autoimmune liver disease (ALD). STUDY DESIGN: This was a retrospective, cross-sectional study of children with a biopsy-proven diagnosis of NAFL, NASH, autoimmune hepatitis (AIH), or primary sclerosing cholangitis (PSC) and a body mass index (BMI) >85th percentile treated between 2007 and 2016. RESULTS: A total of 181 patients were identified, including 31 (17%) with NAFL, 121 (67%) with NASH, 12 (6.6%) with ALD (AIH, PSC, or overlap), and 17 (9.4%) with combined ALD and NAFLD. Antinuclear antibody (ANA), anti-actin antibody, and anti-liver kidney microsomal (LKM) antibody were positive in 16.1%, 13.8%, and 0%, respectively, of the patients with NAFL and in 32.8%, 15.5%, and 0%, respectively, of those with NASH. Total immunoglobulin G (IgG) was elevated in 27.3% of the patients with NAFL and in 47.7% of those with NASH, but in 100% of those with ALD. The positive predictive value of LKM was 100% for ALD but only 29% for ANA and 46% for anti-actin antibody. CONCLUSIONS: False-positive rates of autoantibodies were higher in pediatric patients with overweight and obesity with NAFLD compared with the general adult population. Positive LKM had the highest specificity and positive predictive value, and elevated IgG level had the highest sensitivity for ALD. The presence of autoantibodies does not signal more severe NAFLD in children. BMI >98th percentile seems to be an important breakpoint above which ALD is less likely.

Variation in immunosuppression practices among pediatric liver transplant centers-Society of Pediatric Liver Transplantation survey results.

BACKGROUND: Variation in IS exists among pediatric liver transplant centers. While individual centers may publish their practice paradigms, current data on practices as a whole are lacking. This study sought to ascertain the IS protocols of pediatric liver transplant centers within the SPLIT to better understand variability and similarities among peer institutions. METHODS: A 27-item questionnaire was developed within the SPLIT Quality Improvement and Clinical Care Committee. The survey collected data regarding center demographics, IS practices, and treatment of acute cellular rejection. RESULTS: Twenty-eight (64%) SPLIT centers responded with 22 (79%) centers performing more than 10 transplants per year and 17 (61%) following more than 100 post-transplant recipients. All centers use a written protocol, and 25 (89%) have a dedicated transplant pharmacist/PharmD. Twenty-five (89%) centers use steroids for induction alone or in combination with thymoglobulin/interleukin-2 antibodies. All centers use tacrolimus for initial maintenance therapy. Most centers have specialized protocols for ABO-incompatible transplants, recipients with renal dysfunction, autoimmune liver diseases, and liver tumors. Treatment of rejection varied but was associated with escalation in IS. CONCLUSION: IS practices among pediatric liver transplant centers are similar including the use of written protocols, pharmacy involvement, steroids for induction, tacrolimus as initial IS, tacrolimus reduction/delay for renal dysfunction, and escalation of IS with rejection severity. However, other IS practices show wide variability including treatment for ABO-incompatible grafts and presumed rejection. This study serves as a foundation to guide prospective research linking IS practice to outcomes to determine best practice.

Quality improvement project to improve vaccinations in the pediatric liver transplant population.

OBJECTIVES: A quality improvement approach was used to increase pediatric liver transplant recipient live and inactive vaccination rates by assessing titers and recommending vaccinations. METHODS: A new screening and immunization process for both live and inactive vaccines was discussed with families at their annual visit. Antibody titers for varicella, measles, mumps, rubella, Haemophilus influenzae type B, hepatitis A, and hepatitis B were obtained. Specific criteria were developed for live virus vaccination candidacy. Vaccines were recommended based on patient titers and vaccination candidacy criteria. Surveillance for adverse effects to live vaccines was performed. Repeat titers were obtained approximately 1-month post-vaccine administration. RESULTS: After PDSA cycle 1, 99% (71/72) of pediatric liver transplant patients had titers obtained. Live vaccines were recommended for 32 patients and 16 (50%) were vaccinated. Inactive vaccines were recommended to 64 patients, and 31 (48%) were vaccinated. Eight of 13 (62%) patients with follow-up titers achieved immunity for inactive vaccines. Zero patients had an adverse reaction to any live vaccine. Ten of 12 (83%) patients with follow-up titers achieved immunity from live vaccines. The most common barriers to receive live vaccines included not scheduling appointment with primary care provider (n = 3) and "non-vaccinators" (n = 3). CONCLUSIONS: Administering live and inactive vaccines to select pediatric liver transplant patients appears to be safe and effective in our studied population. For PDSA cycle 2, we will continue our current practice and consider offering vaccines in transplant clinic, since this was a barrier to vaccination identified during PDSA cycle 1.

Severe Acute Respiratory Syndrome Coronavirus-2 Infection in Children With Liver Transplant and Native Liver Disease: An International Observational Registry Study.

OBJECTIVE: Increased mortality risk because of severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) infection in adults with native liver disease (LD) and liver transplant (LT) is associated with advanced age and comorbid conditions. We aim to report outcomes for children with LD and LT enrolled in the NASPGHAN/SPLIT SARS-CoV2 registry. METHODS: In this multicenter observational cohort study, we collected data from 91 patients <21 years (LD 44, LT 47) with laboratory-confirmed SARS-CoV2 infection between April 21 and September 17, 2020. RESULTS: Patients with LD were more likely to require admission (70% vs 43% LT, P = 0.007) and pediatric intensive care unit (PICU) management (32% vs 4% LT, P = 0.001). Seven LD patients required mechanical ventilation (MV) and 2 patients died; no patients in the LT cohort died or required MV. Four LD patients presented in pediatric acute liver failure (PALF), 2 with concurrent multisystem inflammatory syndrome in children (MIS-C); all recovered without LT. Two LD patients had MIS-C alone and 1 patient died. Bivariable logistic-regression analysis found that patients with nonalcoholic fatty LD (NAFLD) (odds ratio [OR] 5.6, P = 0.02) and LD (OR 6.1, P = 0.01, vs LT) had higher odds of severe disease (PICU, vasopressor support, MV, renal replacement therapy or death). CONCLUSIONS: Although not directly comparable, LT recipients had lower odds of severe SARS-CoV2 infection (vs LD), despite immunosuppression burden. NAFLD patients reported to the registry had higher odds of severe SARS-CoV2 disease. Future controlled studies are needed to evaluate effective treatments and further stratify LD and LT patients with SARS-CoV2 infection.

Vedolizumab Therapy in Children With Primary Sclerosing Cholangitis: Data From the Pediatric Primary Sclerosing Cholangitis Consortium.

OBJECTIVES: Most patients with primary sclerosing cholangitis (PSC) also have inflammatory bowel disease (IBD). The liver and colon express MAdCAM-1, a target of lymphocyte homing integrins. Vedolizumab (VDZ) is an α4ß7 integrin antibody used to treat IBD. We investigated liver outcomes in children with PSC-IBD treated with VDZ. METHODS: Patients were identified within the Pediatric PSC Consortium, a multicenter research registry. Retrospective demographic, phenotypic, biochemical, radiological, histopathologic and IBD data for up to 1 year of VDZ therapy were collected. Liver biochemical and IBD responses were defined as: a 75% or greater reduction in initial γ-glutamyltransferase (GGT), or a GGT that fell to <50 IU/L and improved Mayo endoscopy grade or IBD activity scores after 9 to 12 months. RESULTS: Thirty-seven patients were identified from 19 centers. VDZ was initiated at median age of 16 years [IQR 15-18], 69% were male, 65% had large duct involvement, 19% had (Metavir F3/F4) fibrosis and 59% had ulcerative colitis. Of 32 patients with abnormal GGT at baseline, 22% had a liver biochemical response after 9 to 12 months. For IBD, 32% achieved remission, 30% had a clinical response, and 38% had no response. Final GGT after 9 to 12 months was 51 [IQR 28-71] in IBD patients in remission versus 127 [IQR 63-226] in those with active IBD, (P = 0.066). CONCLUSIONS: Liver biochemistry worsened over time in IBD unresponsive to VDZ but remained unchanged in IBD patients in remission. VDZ did not improve liver biochemistry in pediatric PSC-IBD. Progressive liver disease may be more common in patients with medically refractory IBD.

Assessing the Validity of Adult-derived Prognostic Models for Primary Sclerosing Cholangitis Outcomes in Children.

BACKGROUND: Natural history models for primary sclerosing cholangitis (PSC) are derived from adult patient data, but have never been validated in children. It is unclear how accurate such models are for children with PSC. METHODS: We utilized the pediatric PSC consortium database to assess the Revised Mayo Clinic, Amsterdam-Oxford, and Boberg models. We calculated the risk stratum and predicted survival for each patient within each model using patient data at PSC diagnosis, and compared it with observed survival. We evaluated model fit using the c-statistic. RESULTS: Model fit was good at 1 year (c-statistics 0.93, 0.87, 0.82) and fair at 10 years (0.78, 0.75, 0.69) in the Mayo, Boberg, and Amsterdam-Oxford models, respectively. The Mayo model correctly classified most children as low risk, whereas the Amsterdam-Oxford model incorrectly classified most as high risk. All of the models underestimated survival of patients classified as high risk. Albumin, bilirubin, AST, and platelets were most associated with outcomes. Autoimmune hepatitis was more prevalent in higher risk groups, and over-weighting of AST in these patients accounted for the observed versus predicted survival discrepancy. CONCLUSIONS: All 3 models offered good short-term discrimination of outcomes but only fair long-term discrimination. None of the models account for the high prevalence of features of autoimmune hepatitis overlap in children and the associated elevated aminotransferases. A pediatric-specific model is needed. AST, bilirubin, albumin, and platelets will be important predictors, but must be weighted to account for the unique features of PSC in children.

Ursodeoxycholic Acid Therapy in Pediatric Primary Sclerosing Cholangitis: Predictors of Gamma Glutamyltransferase Normalization and Favorable Clinical Course.

OBJECTIVE: To investigate patient factors predictive of gamma glutamyltransferase (GGT) normalization following ursodeoxycholic acid (UDCA) therapy in children with primary sclerosing cholangitis. STUDY DESIGN: We retrospectively reviewed patient records at 46 centers. We included patients with a baseline serum GGT level ≥50 IU/L at diagnosis of primary sclerosing cholangitis who initiated UDCA therapy within 1 month and continued therapy for at least 1 year. We defined "normalization" as a GGT level <50 IU/L without experiencing portal hypertensive or dominant stricture events, liver transplantation, or death during the first year. RESULTS: We identified 263 patients, median age 12.1 years at diagnosis, treated with UDCA at a median dose of 15 mg/kg/d. Normalization occurred in 46%. Patients with normalization had a lower prevalence of Crohn's disease, lower total bilirubin level, lower aspartate aminotransferase to platelet ratio index, greater platelet count, and greater serum albumin level at diagnosis. The 5-year survival with native liver was 99% in those patients who achieved normalization vs 77% in those who did not. CONCLUSIONS: Less than one-half of the patients treated with UDCA have a complete GGT normalization in the first year after diagnosis, but this subset of patients has a favorable 5-year outcome. Normalization is less likely in patients with a Crohn's disease phenotype or a laboratory profile suggestive of more advanced hepatobiliary fibrosis. Patients who do not achieve normalization could reasonably stop UDCA, as they are likely not receiving clinical benefit. Alternative treatments with improved efficacy are needed, particularly for patients with already-advanced disease.

Case report series of a novel application of neostigmine to successfully relieve refractory ileus status post-pediatric orthotopic liver transplantation.

Post-operative ileus is common after abdominal surgeries. Children undergoing liver transplant are at increased risk of ileus for various reasons including multiple abdominal procedures and use of narcotic medications. Ileus can lead to abdominal compartment syndrome and compromise the integrity of the liver graft. In some of these patients, ileus is resistant to standard therapies including stool softeners, bowel stimulants, enemas, and even methylnaltrexone. Neostigmine has been shown in pediatric case series to be efficacious in some children for refractory post-operative ileus. We report three children (9 months, 3 years, and 12 years old) who developed refractory ileus after liver transplant, with one of them developing abdominal compartment syndrome, who were treated successfully with continuous infusions of neostigmine. Clinical responses included passage of flatus and stool and improvement in abdominal distension. All patients tolerated the infusion without serious adverse effects such as bradycardia or bronchospasm. Neostigmine was used safely in our patients and may be safe and efficacious for the treatment of refractory ileus in pediatric patients after liver transplantation. Neostigmine should be considered early in the treatment of these patients.

Hemophagocytic lymphohistiocytosis mimicking neonatal hemochromatosis.

Hemophagocytic lymphohistiocytosis (HLH) is a potentially fatal illness characterized by impaired natural killer (NK) cell and cytotoxic T-cell function. Patients develop systemic inflammation, multisystem organ dysfunction, and if untreated, death. Patients who present in the neonatal period often have atypical presentations with evidence of liver dysfunction and cholestasis; this has a broad differential diagnosis including neonatal infection, congenital liver defects, or other causes of liver dysfunction, such as neonatal hemochromatosis. Here, we present an infant whose diagnosis of familial HLH was confounded by the history of a stillborn sibling with suspected neonatal hemochromatosis, ultimately delaying diagnosis and initiation of curative treatment. This highlights the need to maintain a low threshold for sending HLH work-up concurrently with evaluation of liver diseases in infants with liver dysfunction, to ensure timely diagnosis and initiation of treatment. Clinicians should maintain a high index of suspicion for HLH and be aware that HLH may mimic the findings on liver biopsy seen in neonatal hemochromatosis.

The natural history of primary sclerosing cholangitis in 781 children: A multicenter, international collaboration.

There are limited data on the natural history of primary sclerosing cholangitis (PSC) in children. We aimed to describe the disease characteristics and long-term outcomes of pediatric PSC. We retrospectively collected all pediatric PSC cases from 36 participating institutions and conducted a survival analysis from the date of PSC diagnosis to dates of diagnosis of portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or death. We analyzed patients grouped by disease phenotype and laboratory studies at diagnosis to identify objective predictors of long-term outcome. We identified 781 patients, median age 12 years, with 4,277 person-years of follow-up; 33% with autoimmune hepatitis, 76% with inflammatory bowel disease, and 13% with small duct PSC. Portal hypertensive and biliary complications developed in 38% and 25%, respectively, after 10 years of disease. Once these complications developed, median survival with native liver was 2.8 and 3.5 years, respectively. Cholangiocarcinoma occurred in 1%. Overall event-free survival was 70% at 5 years and 53% at 10 years. Patient groups with the most elevated total bilirubin, gamma-glutamyltransferase, and aspartate aminotransferase-to-platelet ratio index at diagnosis had the worst outcomes. In multivariate analysis PSC-inflammatory bowel disease and small duct phenotypes were associated with favorable prognosis (hazard ratios 0.6, 95% confidence interval 0.5-0.9, and 0.7, 95% confidence interval 0.5-0.96, respectively). Age, gender, and autoimmune hepatitis overlap did not impact long-term outcome. CONCLUSION: PSC has a chronic, progressive course in children, and nearly half of patients develop an adverse liver outcome after 10 years of disease; elevations in bilirubin, gamma-glutamyltransferase, and aspartate aminotransferase-to-platelet ratio index at diagnosis can identify patients at highest risk; small duct PSC and PSC-inflammatory bowel disease are more favorable disease phenotypes. (Hepatology 2017;66:518-527).

Perioperative anticoagulation practices for pediatric liver transplantation.

Despite continued advancements in perioperative care for pediatric liver transplant (LT), graft-threatening vascular occlusion events including hepatic artery thrombosis (HAT) and portal vein thrombosis (PVT) remain a source of significant morbidity and mortality. Perioperative anticoagulation is commonly used for the prevention of HAT and PVT, but evidence-based guidelines are lacking. The goals of this survey were to determine the frequency of use of an anticoagulation protocol and to describe variation in anticoagulation practices among pediatric LT centers. The study consisted of an online survey distributed to members of SPLIT. The survey focused on institutional anticoagulation practices employed to reduce the incidence of graft and life-threatening vascular occlusion events. Responses were received from 31 of 39 SPLIT centers. All respondents report using anticoagulation after pediatric LT, and approximately 90% have institutional anticoagulation protocols. Subgroup analysis of high volume pediatric LT centers revealed similar variability in anticoagulation patterns. All participating SPLIT centers reported the use of post-transplant anticoagulation and nearly all use a protocol. However, there is marked variability in the type and dose of anticoagulation as well as the timing of initiation and duration of therapy across centers.

Challenges in meeting fellowship procedural guidelines in pediatric therapeutic endoscopy and liver biopsy.

OBJECTIVE: The aims of this study were to assess the opportunities for therapeutic endoscopy, liver biopsies, and percutaneous endoscopic gastrostomy (PEG) placements available to fellows during a 3-year pediatric gastroenterology fellowship, and to evaluate access to ancillary procedural-training opportunities. METHODS: Data were collected from 12 pediatric gastroenterology fellowship programs in the United States. Procedures completed in the years 2009-2011 were queried using CPT codes and endoscopy databases. The maximal opportunity for procedures was based on the total procedures performed by the institution in 3 years divided by the total number of fellows in the program. The centers completed a questionnaire regarding ancillary opportunities for endoscopic training. RESULTS: There is significant variability in pediatric endoscopic training opportunities in specialized gastrointestinal (GI) procedures. Under the 1999 guidelines, no centers were able to meet the thresholds for polypectomy and control of nonvariceal bleeding. The 2013 guidelines allowed the number of programs reaching polypectomy thresholds to increase by 67% but made no difference for control of bleeding despite a decrease in the threshold. Training in PEG placement was not available in 42% of the surveyed centers. Elective ancillary procedural training is offered by 92% of the surveyed centers. CONCLUSIONS: Most training programs do not have the volume of therapeutic endoscopy procedures for all of the fellows to meet the training guidelines. Training in therapeutic endoscopy, PEG placement, and liver biopsy in pediatric GI fellowships should be supplemented using all of the possible options including rotations with adult GI providers and hands-on endoscopy courses. A shift toward evaluating competency via quality measures may be more appropriate.

Non-fatal outcomes of COVID-19 disease in pediatric organ transplantation associates with down-regulation of senescence pathways.

This is a cross-sectional study examining kinetics and durability of immune response in children with solid organ transplants (SOTs) who had COVID-19 disease between November 2020 through June 2022, who were followed for 60-days at a single transplant center. Blood was collected between 1-14 (acute infection), and 15-60 days of a positive PCR (convalescence). SOT children with peripheral blood mononuclear cells (PBMC) cryopreserved before 2019 were non-infected controls (ctrls). PBMCs stimulated with 15-mer peptides from spike protein and anti-CD49d/anti-CD28. Testing done included mass cytometry, mi-RNA sequencing with confirmatory qPCR. 38 children formed the study cohort, 10 in the acute phase and 8 in the convalescence phase. 20 subjects were non-infected controls. Two subjects had severe disease. Subjects in the acute and convalescent phases were different subjects. The median age and tacrolimus level at blood draw was not significantly different. There was no death, and no subject was lost to follow-up. During acute infection CD57 expression was low in NKT, Th17 effector memory, memory Treg, CD4-CD8-, and γδT cells (p = 0.01, p = 0.04, p = 0.03, p = 0.03, p = 0.004 respectively). The frequencies of NK and Th2 effector memory cells increased (p = 0.01, p = 0.02) during acute infection. Non-switched memory B and CD8 central memory cell frequencies were decreased during acute infection (p = 0.02; p = 0.02), but the decrease in CD8 central memory cells did not persist. CD4-CD8- and CD14 monocyte frequencies increased during recovery (p = 0.03; p = 0.007). Our observations suggest down regulation of CD57 with absence of NK cell contraction protect against death from COVID-19 disease in children with SOTs.

Alterations in ventricular structure and function in obese adolescents with nonalcoholic fatty liver disease.

OBJECTIVE: To determine the association among nonalcoholic fatty liver disease (NAFLD), metabolic function, and cardiac function in obese adolescents. STUDY DESIGN: Intrahepatic triglyceride (IHTG) content (magnetic resonance spectroscopy), insulin sensitivity and ß-cell function (5-hour oral glucose tolerance test with mathematical modeling), and left ventricular function (speckle tracking echocardiography) were determined in 3 groups of age, sex, and Tanner matched adolescents: (1) lean (n=14, body mass index [BMI]=20±2 kg/m2); (2) obese with normal (2.5%) IHTG content (n=15, BMI=35±3 kg/m2); and (3) obese with increased (8.7%) IHTG content (n=15, BMI=37±6 kg/m2). RESULTS: The disposition index (ß-cell function) and insulin sensitivity index were ∼45% and ∼70% lower, respectively, and whole body insulin resistance, calculated by homeostasis model of assessment-insulin resistance (HOMA-IR), was ∼60% greater, in obese than in lean subjects, and ∼30% and ∼50% lower and ∼150% greater, respectively, in obese subjects with NAFLD than those without NAFLD (P<.05 for all). Left ventricular global longitudinal systolic strain and early diastolic strain rates were significantly decreased in obese than in lean subjects, and in obese subjects with NAFLD than those without NAFLD (P<.05 for all), and were independently associated with HOMA-IR (ß=0.634). IHTG content was the only significant independent determinant of insulin sensitivity index (ß=-0.770), disposition index (ß=-0.651), and HOMA-IR (ß=0.738). CONCLUSIONS: These findings demonstrate that the presence of NAFLD in otherwise asymptomatic obese adolescents is an early marker of cardiac dysfunction.