Homozygous missense variants in YKT6 result in loss of function and are associated with developmental delay, with or without severe infantile liver disease and risk for hepatocellular carcinoma.

PURPOSE: YKT6 plays important roles in multiple intracellular vesicle trafficking events but has not been associated with Mendelian diseases. METHODS: We report 3 unrelated individuals with rare homozygous missense variants in YKT6 who exhibited neurological disease with or without a progressive infantile liver disease. We modeled the variants in Drosophila. We generated wild-type and variant genomic rescue constructs of the fly ortholog dYkt6 and compared their ability in rescuing the loss-of-function phenotypes in mutant flies. We also generated a dYkt6KozakGAL4 allele to assess the expression pattern of dYkt6. RESULTS: Two individuals are homozygous for YKT6 [NM_006555.3:c.554A>G p.(Tyr185Cys)] and exhibited normal prenatal course followed by failure to thrive, developmental delay, and progressive liver disease. Haplotype analysis identified a shared homozygous region flanking the variant, suggesting a common ancestry. The third individual is homozygous for YKT6 [NM_006555.3:c.191A>G p.(Tyr64Cys)] and exhibited neurodevelopmental disorders and optic atrophy. Fly dYkt6 is essential and is expressed in the fat body (analogous to liver) and central nervous system. Wild-type genomic rescue constructs can rescue the lethality and autophagic flux defects, whereas the variants are less efficient in rescuing the phenotypes. CONCLUSION: The YKT6 variants are partial loss-of-function alleles, and the p.(Tyr185Cys) is more severe than p.(Tyr64Cys).

Constructing an Intent-to-Treat Score Index to Predict Survival Outcomes in Pediatric Liver Transplant Recipients.

BACKGROUND: Waitlist and posttransplant outcomes have been widely reported for pediatric liver transplantation. Yet, analyzing these metrics individually fails to provide a holistic perspective for patients and their families. Intent-to-treat (ITT) analysis fills this gap by studying the associations between waitlist outcomes, organ availability, and posttransplant outcomes. Our study aimed to construct a predictive index utilizing ITT analysis for pediatric liver transplant recipients (Pedi-ITT). METHODS: We performed a retrospective analysis utilizing de-identified data provided by the United Network for Organ Sharing (UNOS) from March 1, 2002, to December 31, 2021. We analyzed data for 12 926 pediatric recipients (age <18). We conducted a univariate and multivariable logistic regression to find the significant predictive factors affecting ITT survival. A scoring index was constructed to stratify outcome risk on the basis of the significant factors identified by regression analysis. RESULTS: Multivariable analysis found the following factors to be significantly associated with death on the waitlist or after transplant: gender, diagnosis, UNOS region, ascites, diabetes mellitus, age at the time of listing, serum sodium at the time of listing, total bilirubin at the time of listing, serum creatinine at the time of listing, INR at the time of listing, history of ventilator use, and history of re-transplantation. Using receiver operator characteristic analysis, the Pedi-ITT index had a c-statistic of 0.79 (95% confidence interval [CI]: 0.76-0.82). The c-statistics of the Model for End-Stage Liver Disease/Pediatric for End-Stage Liver Disease and pediatric version of the Survival Outcomes Following Liver Transplantation score indices were 0.74 (CI: 0.71-0.76) and 0.69 (CI: 0.66-0.72), respectively. CONCLUSIONS: The Pedi-ITT index provides an additional prognostic model with moderate predictive power to assess outcomes associated with pediatric liver transplantation. Further analysis should focus on increasing the predictive power of the index.

Estimating risk of prolonged mechanical ventilation after liver transplantation in children: PROVE-ALT score.

BACKGROUND: Children at high risk for prolonged mechanical ventilation (PMV) after liver transplantation (LT) need to be identified early to optimize pulmonary support, allocate resources, and improve surgical outcomes. We aimed to develop and validate a metric that can estimate risk for Prolonged Ventilation After LT (PROVE-ALT). METHODS: We identified preoperative risk factors for PMV by univariable analysis in a retrospective cohort of pediatric LT recipients between 2011 and 2017 (n = 205; derivation cohort). We created the PROVE-ALT score by mapping multivariable logistic regression coefficients as integers, with cutoff values using the Youden Index. We validated the score by C-statistic in a retrospectively collected separate cohort of pediatric LT recipients between 2018 and 2021 (n = 133, validation cohort). RESULTS: Among total 338 patients, 21% (n = 72) were infants; 49% (n = 167) had cirrhosis; 8% (n = 27) required continuous renal replacement therapy (CRRT); and 32% (n = 111) required management in hospital (MIH) before LT. Incidence of PMV post-LT was 20% (n = 69) and 3% (n = 12) required tracheostomy. Independent risk factors (OR [95% CI]) for PMV were cirrhosis (3.8 [1-14], p = .04); age <1-year (8.2 [2-30], p = .001); need for preoperative CRRT (6.3 [1.2-32], p = .02); and MIH before LT (12.4 [2.1-71], p = .004). PROVE-ALT score ≥8 [Range = 0-21] accurately predicted PMV in the validation cohort with 73% sensitivity and 80% specificity (AUC: 0.81; 95% CI: 0.71-0.91). CONCLUSION: PROVE-ALT can predict PMV after pediatric LT with a high degree of sensitivity and specificity. Once externally validated in other centers, PROVE-ALT will empower clinicians to plan patient-specific ventilation strategies, provide parental anticipatory guidance, and optimize hospital resources.

Predicting wait time for pediatric kidney transplant: a novel index.

BACKGROUND: Over one thousand pediatric kidney transplant candidates are added to the waitlist annually, yet the prospective time spent waiting is unknown for many. Our study fills this gap by identifying variables that impact waitlist time and by creating an index to predict the likelihood of a pediatric candidate receiving a transplant within 1 year of listing. This index could be used to guide patient management by giving clinicians a potential timeline for each candidate's listing based on a unique combination of risk factors. METHODS: A retrospective analysis of 3757 pediatric kidney transplant candidates from the 2014 to 2020 OPTN/UNOS database was performed. The data was randomly divided into a training set, comprising two-thirds of the data, and a testing set, comprising one-third of the data. From the training set, univariable and multivariable logistic regressions were used to identify significant predictive factors affecting wait times. A predictive index was created using variables significant in the multivariable analysis. The index's ability to predict likelihood of transplantation within 1 year of listing was validated using ROC analysis on the training set. Validation of the index using ROC analysis was repeated on the testing set. RESULTS: A total of 10 variables were found to be significant. The five most significant variables include the following: blood group, B (OR 0.65); dialysis status (OR 3.67); kidney disease etiology, SLE (OR 0.38); and OPTN region, 5 (OR 0.54) and 6 (OR 0.46). ROC analysis of the index on the training set yielded a c-statistic of 0.71. ROC analysis of the index on the testing set yielded a c-statistic of 0.68. CONCLUSIONS: This index is a modest prognostic model to assess time to pediatric kidney transplantation. It is intended as a supplementary tool to guide patient management by providing clinicians with an individualized prospective timeline for each candidate. Early identification of candidates with potential for prolonged waiting times may help encourage more living donation including paired donation chains.

A modified Kidney Donor Risk Index for pediatric kidney transplant recipients.

BACKGROUND: The Kidney Donor Risk Index (KDRI) by Rao et al. was developed to measure the quality of kidney allografts. While Rao's KDRI has been found to be a robust measure of kidney allograft survival for adult kidney transplant recipients, many studies have indicated the need to create a distinct pediatric KDRI. METHODS: Our retrospective study utilized data from the United Network for Organ Sharing database. We examined 9295 deceased donor recipients' data for age < 18 years from 1990 to 2020. We performed a multivariate Cox regression to determine the significant recipient and transplant factors impacting pediatric kidney allograft survival. RESULTS: Multivariate analysis found 5 donor factors to be independently associated with graft failure or recipient death: age, female sex, anoxia as the cause of death, history of cigarette use, and cold ischemia time. Using receiver operator characteristic (ROC) curve analysis and analyzing the predictive value of each KDRI at 1, 5, and 10 years, the proposed pediatric KDRI had a statistically significant and higher predictive value for pediatric recipients at 5 (0.60 versus 0.57) and 10 years (0.61 versus 0.57) than the Rao KDRI. CONCLUSIONS: The proposed pediatric KDRI may provide a more accurate and simpler index to assess the quality of kidney allografts for pediatric recipients. However, due to the mild increase in predictive capabilities over the Rao index, the study serves as a proof of concept to develop a pediatric KDRI. Further studies should focus on increasing the index's predictive capabilities. A higher resolution version of the Graphical abstract is available as Supplementary information.

Marginal allografts in liver transplantation have a limited impact on length of stay.

The study of marginal liver transplant outcomes, including post-transplant length of stay (LOS), is necessary for determining the practicality of their use. 50 155 patients who received transplants from 2012 to 2020 were retrospectively analyzed with data from the Scientific Registry of Transplant Recipients database using Kaplan-Meier survival curves and multivariable Cox regression. Six different definitions were used to classify an allograft as being marginal: 90th percentile Donor Risk Index (DRI) allografts, donation after cardiac death (DCD) donors, national share donors, donors over 70, donors with > 30% macrovesicular steatosis, or 90th percentile Discard Risk Index donors. 24% (n = 12 124) of subjects received marginal allografts. Average LOS was 15.6 days among those who received standard allografts. Among those who received marginal allografts, LOS was found to be highest in those who received 90th percentile DRI allografts at 15.6 days, and lowest in those who received DCD allografts at 12.7 days. Apart from fatty livers (95% CI .86-.98), marginal allografts were not associated with a prolonged LOS. We conclude that accounting for experience and recipient matching, transplant centers may be more aggressive in their use of extended criteria donors with limited fear of increasing LOS and its associated costs.

Our evolution in the treatment of hepatic artery and portal vein thrombosis in pediatric liver transplantation: Success with catheter-directed therapies.

BACKGROUND: In pediatric liver transplant recipients, hepatic artery thrombosis and portal vein thrombosis are major causes of acute graft failure and mortality within 30 days of transplantation. There is, however, a strong possibility of graft salvage if flow can be re-established to reduce ischemic injury. The current standard treatment is surgical revascularization, and if unsuccessful, retransplantation. Due to our success in treating these complications with catheter-directed therapies, we sought to summarize and publish the outcomes of all patients who experienced hepatic artery thrombosis or portal vein thrombosis within 30 days of liver transplantation. METHODS: We conducted a retrospective cohort analysis of 27 pediatric liver transplant recipients who experienced hepatic artery thrombosis (n = 13), portal vein thrombosis (n = 9), or both (n = 5) between September 2012 and March 2021. We collected and tabulated data on the patients and therapies performed to treat them, including success rates, primary and secondary patency, and clinical outcomes. RESULTS: Among these patients, 6 were managed with anticoagulation and relisting for transplant and 21 had a primary revascularization attempt. Surgical recanalization was attempted in 7 patients of which 3 had successful recanalization (43%) and catheter-directed recanalization was attempted in 14 patients with 100% success in re-establishing blood flow to the graft. Additionally, patency was increased, and mortality was decreased in patients treated with catheter-directed recanalization compared to surgical revascularization or anticoagulation alone. CONCLUSION: This data illustrates the need to further investigate catheter-directed thrombolysis as a potential first-line treatment for postoperative HAT and PVT in pediatric liver transplant recipients.

A new chapter in an evolving pandemic: Successful pediatric liver transplantation with SARS-CoV-2+ donors.

BACKGROUND: Amid a viral pandemic with poorly understood transmissibility and pathogenicity in the pediatric patient, we report the first pediatric liver transplants utilizing allografts from SARS-CoV-2+ donors. METHODS: We describe the outcomes of two pediatric liver transplant recipients who received organs from SARS-CoV-2 nucleic acid test-positive (NAT+) donors. Data were obtained through the respective electronic medical record system and UNet DonorNet platform. RESULTS: The first donor was a 3-year-old boy succumbing to head trauma. One of four nasopharyngeal (NP) swabs and 1 of 3 bronchoalveolar lavage (BAL) NAT tests demonstrated SARS-CoV-2 infection before organ procurement. The second donor was a 16-month-old boy with cardiopulmonary arrest of unknown etiology. Three NAT tests (2 NP swab/1 BAL) prior to procurement failed to detect SARS-CoV-2. The diagnosis was made when the medical examiner repeated 2 NP swab NATs and an archive plasma NAT, all positive for SARS-CoV-2. Both 2-year-old recipients continue to do well 8 months post-transplant, with excellent graft function and no evidence of SARS-CoV-2 transmission. CONCLUSIONS: This is the first report to describe successful pediatric liver transplantation from SARS-CoV-2+ donors. These data reinforce the adult transplant experience and support the judicious use of SARS-CoV-2+ donors for liver transplantation in children. With SARS-CoV-2 becoming endemic, the concern for donor-derived viral transmission must now be weighed against the realized benefit of life-saving transplantation in the pediatric population as we continue to work toward donor pool maximization.

Survey of public attitudes towards imminent death donation in the United States.

Imminent death donation (IDD) is described as living organ donation prior to a planned withdrawal of life-sustaining care in an imminently dying patient. Although IDD was ethically justified by United Network for Organ Sharing, the concept remains controversial due to presumed lack of public support. The aim of this study was to evaluate the public's attitudes towards IDD. A cross-sectional survey was conducted of US adults age >18 years (n = 2644). The survey included a case scenario of a patient with a devastating brain injury. Responses were assessed on a 5-point Likert scale. Results showed that 68% - 74% of participants agreed or strongly agreed with IDD when posed as a general question and in relation to the case scenario. Participants were concerned about "recovery after a devastating brain injury" (34%), and that "doctors would not try as hard to save a patient's life" (33%). Only 9% of participants would be less likely to trust the organ donation process. In conclusion, our study demonstrates strong public support for IDD in the case of a patient with a devastating brain injury. Notably, participants were not largely concerned with losing trust in the organ donation process. These results justify policy change towards imminent death donation.

Factors associated with long-term graft survival in pediatric kidney transplant recipients.

Pediatric kidney transplant recipients generally have good outcomes post-transplantation. However, the younger age and longer life span after transplantation in the pediatric population make understanding the multifactorial nature of long-term graft survival critical. This investigation analyzes factors associated with 10-year survival to identify areas for improvement in patient care. Kaplan-Meier with log-rank test and univariable and multivariable logistic regression methods were used to retrospectively analyze 7785 kidney transplant recipients under the age of 18 years from January 1, 1998, until March 9, 2008, using United Network for Organ Sharing (UNOS) data. Our end-point was death-censored 10-year graft survival after excluding recipients whose grafts failed within one year of transplant. Recipients aged 5-18 years had lower 10-year graft survival, which worsened as age increased: 5-9 years (OR: 0.66; CI: 0.52-0.83), 10-14 years (OR: 0.43; CI: 0.33-0.55), and 15-18 years (OR: 0.34; CI: 0.26-0.44). Recipient African American ethnicity (OR: 0.67; CI: 0.58-0.78) and Hispanic donor ethnicity (OR: 0.82; CI: 0.72-0.94) had worse outcomes than other donor and recipient ethnicities, as did patients on dialysis at the time of transplant (OR: 0.82; CI: 0.73-0.91). Recipient private insurance status (OR: 1.35; CI: 1.22-1.50) was protective for 10-year graft survival. By establishing the role of age, race, and insurance status on long-term graft survival, we hope to guide clinicians in identifying patients at high risk for graft failure. This study highlights the need for increased allocation of resources and medical care to reduce the disparity in outcomes for certain patient populations.

A learning curve in using orphan liver allografts for transplantation.

Given the critical shortage of donor livers, marginal liver allografts have potential to increase donor supply. We investigate trends and long-term outcomes of liver transplant using national share allografts transplanted after rejection at the local and regional levels. We studied a cohort of 75 050 candidates listed in the Organ Procurement and Transplantation Network for liver transplantation between 2002 and 2016. We compared patients receiving national share and regional/local share allografts from 2002-2006, 2007-2011, and 2012-2016, performing multivariate Cox regression for graft survival. Recipient and center-level covariates that were not significant (P < .05) were removed. Graft survival of national share allografts improved over time. National share allografts had a 26% increased risk for graft failure in 2002-2006 but no impact on graft survival in 2007-2011 and 2012-2016. The cold ischemia time (CIT) of national share allografts decreased from 10.4 to 8.0 hours. We demonstrate that CIT had significant impact on graft survival using national share allografts (CIT <6 hours: hazard ratio 0.75 and CIT >12 hours: hazard ratio 1.25). Despite a trend toward sicker recipients and poorer quality allografts, graft survival outcomes using national share allografts have improved to benchmark levels. Reduction in cold ischemia time is a possible explanation.

Aggressive utilization of liver allografts: Improved outcomes over time.

BACKGROUND: Aggressive acceptance of liver allografts has driven utilization of marginal allografts. Our aim was to assess the impact of the aggressive phenotype on transplant center outcomes over time. METHODS: We used a cohort of 148 361 candidates from the Organ Procurement and Transplantation Network for liver transplantation between 2002 and 2016 in 134 centers. Using the Discard Risk Index, we designated high probability discard allografts by the top 10th percentile for likelihood of discard. Aggressive phenotype was defined by usage of high probability discard (HPD) allografts (top 10th percentile). Our analysis of survival on waitlist and graft survival after transplantation included a comprehensive list of center level covariates across three equal time periods (2002-2006, 2007-2011, and 2012-2016). RESULTS: After adjusting for recipient and center-level factors, aggressive centers had improving graft survival over time. Aggressive vs non-aggressive centers: 2002-2006 HR 1.12 (1.05-1.19), 2007-2011 HR 1.13 (1.05-1.22), 2012-2016 HR 0.99 (0.89-1.10). Aggressive centers had improved waitlist survival compared with non-aggressive centers after adjusting for allograft disparity. CONCLUSIONS: Aggressive phenotype had a positive impact on waitlist survival, and graft survival in aggressive centers have improved to benchmark levels over time. These findings serve as justification for aggressive utilization of allografts.

Pediatric length-of-stay index following liver transplantation.

BACKGROUND: PELD scores are used to reduce waitlist mortality, but they do not accurately predict likelihood of prolonged length-of-stay or higher costs associated with it. This study aims to create a pediatric length-of-stay (LOS) index to predict increased risk of prolonged stay following liver transplantation. METHODS: The scoring system generated predicts length-of-stay following pediatric liver transplantation. With univariate and multivariate analyses on data from 5669 pediatric liver transplant recipients, independent recipient/donor risk factors for prolonged stay (>30 days) were identified. Multiple imputations accounted for missing variables. RESULTS: The most significant factors were ICU admission (OR 2.92, CI 2.27-3.75), recipient bilirubin >32 (OR 2.35, CI 1.70-3.25), and hemodialysis 1 week before transplantation (OR 2.27, CI 1.57-3.27). The LOS index assigns weighted scoring points to factors to predict prolonged stay (C-statistic of .72). The index demonstrated discrimination across the population after dividing it into quartiles for prolonged stay. CONCLUSIONS: The pediatric LOS index, utilizing 13 donor/recipient factors, can assess the risk for pediatric liver transplantation prolonged stay. Important predictive factors are hemodialysis, ICU admission, recipient weight and bilirubin, and recipient life support status.

Trends in pediatric liver transplant donors and deceased donor circumstance of death in the United States, 2002-2015.

While much of the discussion regarding expanding the donor pool for pediatric liver transplantation has surrounded the use of technical variant grafts, little attention has been directed toward changes in the deceased donor population. The aim of this study was to investigate trends in the circumstance of the death of deceased donors used for pediatric liver transplantation. All pediatric liver transplant recipients transplanted between 2002 and 2015 were identified in the UNOS database and were categorized based on the donor circumstance of death. There was no significant correlation between year of transplantation and number of pediatric liver transplants performed, pediatric donors, split livers, or living donors. There was a significant downward trend in donors from motor vehicle fatalities and an upward trend in suicide, non-MVA, and death due to natural causes. There was also an upward trend in drowning, one of the most common mechanisms of death among non-MVA in 2015. While the number of donors who died in MVA has fallen, the number of deceased donors who died from suicide, natural causes, and non-MVA, especially drowning, has increased, maintaining the overall number of pediatric deceased donor livers transplanted.

Orthotopic liver transplantation for Sensenbrenner syndrome.

Sensenbrenner syndrome, or cranioectodermal dysplasia, is a rare heterogeneic autosomal recessive disorder, affecting ~1 of 1 000 000 live births. The syndrome usually manifests within the first year of life and can present with progressive liver and renal involvement. For all Sensenbrenner patients, renal and liver diseases are the main contributors of morbidity and mortality. In this report, we present the case of a 7-year-old boy with congenital liver disease progressing to liver failure secondary to Sensenbrenner syndrome. For this patient, evidence of liver dysfunction was evident from 2 months of age and progressed to frank cirrhosis and severe portal hypertension with multiple episodes of life-threatening variceal bleeding by age 6. This report illustrates the capability of orthotopic liver transplantation as a viable therapy for those pediatric patients suffering from severe liver failure secondary to a congenital ciliopathy, such as Sensenbrenner syndrome. In fact, early emphasis should be placed on the renal and liver involvement associated with Sensenbrenner syndrome with particular consideration for early referral for transplantation in cases with severe disease. Although the condition is rare, clinicians should be aware of it and its association with fatal liver disease to facilitate appropriate evaluation and referral.

Liver transplant length of stay (LOS) index: A novel predictive score for hospital length of stay following liver transplantation.

An index to predict hospital length of stay after liver transplantation could address unmet clinical needs. Length of stay is an important surrogate for hospital costs and efforts to limit stays can preserve our healthcare resources. Here, we devised a scoring system that predicts hospital length of stay following liver transplantation. We used univariate and multivariate analyses on 73 635 adult liver transplant recipient data and identified independent recipient and donor risk factors for prolonged hospital stay (>30 days). Multiple imputation was used to account for missing variables. We identified 22 factors as significant predictors of prolonged hospital stay, including the most significant risk factors: intensive care unit (ICU) admission (OR 1.75, CI 1.58-1.95) and previous transplant (OR 1.60, CI 1.47-1.75). The length of stay (LOS) index assigns weighted risk points to each significant factor in a scoring system to predict prolonged hospital stay after liver transplantation with a c-statistic of 0.75. The LOS index demonstrated good discrimination across the entire population, dividing the cohort into tertiles, which had odds ratios of 2.25 (CI 2.06-2.46) and 7.90 (7.29-8.56) for prolonged hospital stay (>30 days). The LOS index utilizes 22 significant donor and recipient factors to accurately predict hospital length of stay following liver transplantation. The index further demonstrates the basis for a clear clinical recommendation to mitigate risk of long hospitalization by minimizing cold ischemia time.

Selecting DCD Recipients Using Predictive Indices.

Donation after circulatory death (DCD) allografts might represent one of the largest untapped sources of liver allografts. Our aim was to identify independent recipient risk factors that predict mortality in DCD allograft recipients to preselect optimal candidates for successful transplantation. Furthermore, we compared the application of our newly constructed DCD Recipient Selector Index (RSI) score to previously developed models to determine superiority in predicting recipient survival. Methods: Using the Organ Procurement and Transplantation Network database, we performed univariate and multivariate retrospective analyses on 4228 DCD liver allograft recipients. Results: We identified 8 significant factors and incorporated them into the weighted RSI to predict 3-mo survival following DCD liver transplantation with a C-statistic of 0.6971. The most significant recipient risk factors were recipient serum sodium levels >150 mEq/L at transplant, recipient albumin <2.0 g/dL at transplant, and a history of portal vein thrombosis. Because Model for End-Stage Liver Disease (MELD) score components were included as individual predictors, the DCD RSI predicts survival independently of MELD. Upon comparison with 3 previous recipient risk scores-Balance of Risk, Renal Risk Index, Patient-Survival Outcomes Following Liver Transplantation-the DCD RSI was determined to be superior at selecting optimal candidates pre-DCD transplantation, yielding a C-statistic of 0.6971. Conclusions: After verifying the performance of predictive indices for selection of DCD recipients, the DCD RSI is best used to preselect patients for optimized outcomes after DCD transplantation. This can increase utilization of DCD donors by improving outcomes.

Elevated bile acids are associated with left ventricular structural changes in biliary atresia.

BACKGROUND: In children with biliary atresia (BA), pathologic structural changes within the heart, which define cirrhotic cardiomyopathy, are associated with adverse perioperative outcomes. Despite their clinical relevance, little is known about the pathogenesis and triggers of pathologic remodeling. Bile acid excess causes cardiomyopathy in experimental cirrhosis, but its role in BA is poorly understood. METHODS: Echocardiographic parameters of left ventricular (LV) geometry [LV mass (LVM), LVM indexed to height, left atrial volume indexed to BSA (LAVI), and LV internal diameter (LVID)] were correlated with circulating serum bile acid concentrations in 40 children (52% female) with BA listed for transplantation. A receiver-operating characteristic curve was generated to determine optimal threshold values of bile acids to detect pathologic changes in LV geometry using Youden index. Paraffin-embedded human heart tissue was separately analyzed by immunohistochemistry for the presence of bile acid-sensing Takeda G-protein-coupled membrane receptor type 5. RESULTS: In the cohort, 52% (21/40) of children had abnormal LV geometry; the optimal bile acid concentration to detect this abnormality with 70% sensitivity and 64% specificity was 152 µmol/L (C-statistics=0.68). Children with bile acid concentrations >152 µmol/L had ∼8-fold increased odds of detecting abnormalities in LVM, LVM index, left atrial volume index, and LV internal diameter. Serum bile acids positively correlated with LVM, LVM index, and LV internal diameter. Separately, Takeda G-protein-coupled membrane receptor type 5 protein was detected in myocardial vasculature and cardiomyocytes on immunohistochemistry. CONCLUSION: This association highlights the unique role of bile acids as one of the targetable potential triggers for myocardial structural changes in BA.