Higher Mortality in Pediatric Liver Transplant Candidates With Sarcopenia

Frailty in Pediatric Liver Disease May Be Associated With an Increased Incidence of Readmissions After Pediatric Liver Transplantation

BACKGROUND

Frailty is a phenotype of cumulative decline leading to decreased physiologic reserve and vulnerability to stressors. Frailty is associated with adverse outcomes after liver transplantation (LT) in adults, but similar data are not available in children. A prospective multicenter study previously determined that frailty is present in 46% of children with end-stage liver disease (ESLD). We utilized this cohort to evaluate the impact of pre-transplant frailty on post-LT outcomes.

METHODS

The study included pediatric participants from the original frailty study across 10 North American transplant centers who had subsequently undergone LT. Clinical outcomes were collected up to 1 year post LT. Participants were stratified by their pre-transplant frailty score (defined by a pre-LT frailty score of ≥ 6.0) and long-term outcomes were compared between groups.

RESULTS

28 (60.7% female, 46.4% biliary atresia) pediatric LT recipients were included, and 54% of children met criteria for frailty (n = 15). Baseline characteristics were comparable between groups; however, those with frailty were significantly more likely to have pre-transplant failure to thrive (33.3% vs. 0%, p = 0.044). Thirty-four hospital readmissions (22 in frail and 12 in non-frail children) occurred in 20 patients. Higher pre-transplant frailty scores were also significantly associated with an increased number of readmissions after transplantation (p = 0.034).

CONCLUSIONS

Pediatric frailty may be associated with the adverse outcome of increased frequency of hospitalization in the first year after pediatric liver transplantation. These data support the concept that frail children should be identified and targeted for prehabilitation prior to LT.

Bioelectrical impedance analysis for measuring body composition and predicting low muscle mass in apparently healthy pediatric outpatients: a retrospective observational study

BACKGROUND

The bioelectrical impedance analysis-derived phase angle is a proposed indicator of sarcopenia in adults. This study assessed the body composition of pediatric outpatients without underlying medical conditions to evaluate the predictive value of the phase angle in identifying low muscle mass, a risk factor for pediatric sarcopenia.

METHODS

Analyses were performed separately for each sex among 480 pediatric outpatients aged 5-18 years. Body composition variables were compared between low and normal body mass index-for-age z-score (BMIz) groups, including correlation analysis between the phase angle and other variables. The receiver operating characteristic curves of the phase angle, body mass index, and fat-free mass index (FFMI) were compared to predict a severely low appendicular skeletal muscle mass index (ASMI), defined as an ASMI below - 1 or - 2 standard deviations based on sex- and ethnicity-specific reference curves derived from dual-energy X-ray absorptiometry.

RESULTS

The low BMIz group showed a greater prevalence of a low fat-mass percentage and severely low ASMI, accompanied by notable changes in fat mass, muscle mass, height-squared adjusted indices, body water, protein, visceral fat area, and the phase angle (P < 0.05) compared with the normal BMIz group. The phase angle exhibited moderate correlations (P < 0.001) with the FFMI and ASMI (positive) and the visceral fat area and the extracellular water/total body water (ECW/TBW) ratio (negative) but no or negligible correlation with fat mass, fat-mass percentage, the fat mass index, or minerals. The phase angle' area under the curve for predicting a severely low ASMI was 0.743-0.785 (sensitivity: 62.3-80.4%; specificity: 67.0-75.0%). The area under the curve of the FFMI was 0.853-0.931 (sensitivity: 78.4-92.9%; specificity: 79.6-87.1%).

CONCLUSIONS

Body composition can identify fat and muscle wasting in children with a normal BMIz. The phase angle moderately correlated with the FFMI, ASMI, visceral fat area, and ECW/TBW ratio. The phase angle is a reasonable, although not a surrogate, indicator of the sarcopenia risk in pediatric outpatients.

Recent advances in the management of pediatric cholestatic liver diseases

Pediatric cholestatic liver diseases are rare conditions that can result from multiple specific underlying etiologies. Among the most common etiologies of pediatric cholestatic liver diseases are biliary atresia, Alagille syndrome (ALGS), and inherited disorders of bile acid transport. These diseases are characterized by episodic or chronic unremitting cholestasis. Due to the chronicity of these conditions, it is imperative to optimize medical management to improve patient quality of life, provide nutritional support, and reduce bile acid toxicity in efforts to slow disease progression. Cholestatic liver diseases remain the leading cause of pediatric liver transplantation, as many underlying disease etiologies have no curative medical therapies. In the present review, we provide an update on the nutritional, medical, and surgical management of pediatric cholestatic liver diseases. As recent advances have occurred in the field with the addition of ileal bile acid transporter (IBAT) inhibitors, we also review the results from prospective clinical trials, including their strengths and limitations. While recent clinical trials have demonstrated improved pruritus using IBAT inhibitors in ALGS and progressive familial intrahepatic cholestasis, establishing medical therapies proven to slow disease progression remains an area of unmet need.

The Emerging Role and Clinical Applications of Morphomics in Diagnostic Imaging

Analytic morphomics refers to the accurate measurement of specific biological markers of human body composition in diagnostic medical imaging. The increasing prevalence of disease processes that alter body composition including obesity, cachexia, and sarcopenia has generated interest in specific targeted measurement of these metrics to possibly prevent or reduce negative health outcomes. Typical morphomic measurements include the area and density of muscle, bone, vascular calcification, visceral fat, and subcutaneous fat on a specific validated axial level in the patient's cross-sectional diagnostic imaging. A distinct advantage of these measurements is that they can be made retrospectively and opportunistically with pre-existing datasets. We provide a narrative review of the current state of art in morphomics, but also consider some potential future directions for this exciting field. Imaging based quantitative assessment of body composition has enormous potential across the breadth and scope of modern clinical practice. From risk stratification to treatment planning, and outcome assessment, all can be enhanced with the use of analytic morphomics. Moreover, it is likely that many new opportunities for personalized medicine will emerge as the field evolves. As radiologists, embracing analytic morphomics will enable us to contribute added value in the care of every patient.

Nutrition in pediatric end-stage liver disease

PURPOSE OF REVIEW

The aim of this review is to outline recent studies relating to nutritional status and outcomes in pediatric end-stage liver disease.

MAIN FINDINGS

Pediatric patients with chronic and end-stage liver disease are at high risk of malnutrition. Given additional growth demands in children and the inherent complications of chronic liver disease, achieving adequate nutrition in these patients remains a challenge. In addition, while guidelines on nutrition in chronic liver disease exist, global approaches and definitions of malnutrition vary. Recent literature has focused on sarcopenia and nutrition-related transplant outcomes, with some studies exploring nutritional assessment and management. Pediatric studies however continue to lag adult research, with limited prospective and interventional studies.

SUMMARY

Optimizing nutrition in pediatric end-stage liver disease remains a challenge, however understanding of the mechanisms and clinical manifestations of malnutrition in this population is improving. Despite these efforts, high quality studies to determine optimal nutrition strategies and interventions are lacking behind adult evidence and should be the focus of future research.

Preservation of fat mass at the expense of lean mass in children with end-stage chronic liver disease

BACKGROUND

Sarcopenia predicts morbidity and mortality in end-stage chronic liver disease (ESCLD). Here, we describe changes in body composition in children with ESCLD before and after liver transplantation (LT).

METHODS

Retrospective analysis of whole body DXA scans performed before and after LT over 4 years. Appendicular and whole-body fat mass and lean mass were expressed as fat mass (FMI) and lean mass (LMI) index z-scores. Sarcopenia was defined as leg LMI z-score <-1.96.

RESULTS

Eighty-three DXA scans of children before or after LT were studied. Sarcopenia had a positive correlation with weight (0.8, p < .01), height (0.48, p < .05), and BMI z-score (0.77, p < .01), as well as arm, trunk, and total mean mass indices. It correlated negatively with indices of hypersplenism: PLTs (-0.57, p < .01), Neu (-0.50, p < .05), WCC (-0.44, p < .05), and days to discharge (-0.46, p < .05). At baseline: 13/25 (52%) children were sarcopenic and stayed in the hospital after LT for longer. Eight were stunted with a higher WCC and Ne/Ly ratio. All had normal FM indices. One year after LT, 12/26 children remained sarcopenic. Seven were stunted. Two years after LT, 5/15 were sarcopenic, and 5 were stunted. Three years after LT, 1/10 was sarcopenic, and 2 were stunted. By 4 years after LT, 1/7 was sarcopenic, and the same one was stunted. FM indices remained normal.

CONCLUSIONS

Sarcopenic patients stayed longer in the hospital after LT. Lean mass indices were mostly within the normal range by 4 years after LT. 32% of children were stunted, and markers of inflammation were correlated with stunting. Fat mass was preserved at the cost of lean mass.

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.

Malnutrition, sarcopenia, and frailty assessment in pediatric transplantation

Nutrition assessment can be challenging in children with end-stage organ disease and in those requiring an organ transplant. The effect of poor nutrition status can exert long-lasting effects on children with end-stage organ disease requiring transplantation. Malnutrition, sarcopenia, and frailty are conditions that require provision of optimal nutrition to prevent or support the treatment of these conditions. Unfortunately, the literature on the assessment of malnutrition, sarcopenia, and frailty in pediatric end-stage organ disease is scarce, thus leading to confusion on how to effectively identify them. Recently, the addition of a variety of validated nutrition and functional assessment techniques has assisted with appropriate assessment of these conditions. The objective of this narrative review is to provide an overview of the current literature for pediatric assessment of malnutrition, sarcopenia, and frailty in the setting of solid organ transplantation and provide practicing nutrition clinicians a solid foundation for learning how to effectively assess these conditions with the current literature available.

Optimizing the pediatric transplant candidate

PURPOSE OF REVIEW

Advances in pediatric transplant parallel those in adult populations; however, there remain critical unique considerations and differences that require specialized knowledge and a specific skill set to optimize care afforded to the pediatric transplant candidate. We introduce general themes regarding optimization of the transplant candidate that are unique to children.

RECENT FINDINGS

The pathologies leading to pediatric organ transplant candidacy differ from adults and a precise understanding of the physiologies and natural histories of such diseases is critical for optimized care. Regardless of etiology, comorbidities including malnutrition, sarcopenia, and developmental delay are seen and often require disease and organ specific approaches to management. Additionally, an understanding of the concepts of developmental immunology and their relevance to transplant is critical.

SUMMARY

When looking to optimize pretransplant care, awareness of the pediatric-specific challenges by the transplant community in addition to organ- and age-specific management strategies enable the best outcomes for children awaiting solid organ transplantation.

Criteria for immediate extubation after pediatric liver transplantation in a single pediatric liver transplant center in Japan

Immediate extubation (IE) following liver transplantation (LT) has become the standard practice, even for pediatric patients. However, no preoperative or postoperative case selection protocols for IE are currently available. We have developed selection criteria for IE following pediatric LT. The aim of this study is to assess the safety and effectiveness of these selection criteria and anesthetic management protocol implemented in our hospital for IE after pediatric LT.

METHOD

This was a retrospective study. The records of all cases undergoing LT in our center from January 2016 to December 2020 were collected. We excluded cases > 18 years old at the time of LT. Enrolled cases were divided into two groups: cases with immediate extubation (IE) or without immediate extubation (NIE). We compared preoperative conditions, intraoperative management, and postoperative courses. Finally, we classified NIE group patients into cases extubated at postoperative day 1 (early; E-NIE) and others (delayed; D-NIE) and compared their underlying diseases and postoperative courses.

RESULTS

In the IE group, there were 81 cases, while the NIE group consisted of 185 cases. All patients in the IE group were successfully extubated without any instances of re-intubation due to respiratory failure. Within the E-NIE group, comprising 130 cases, all patients were ultimately extubated without the need for tracheostomy. However, in the D-NIE group, which encompassed 53 cases, seven patients required tracheostomy.

CONCLUSION

In our center, the implementation of our anesthesia management protocol and the use of pre/postoperative case selection criteria have allowed for the safe practice of IE following pediatric LT. However, it should be noted that patients who cannot be extubated by Postoperative Day 1 (POD1) may be at an increased risk of requiring a tracheostomy. When contemplating IE, it is crucial to take into account the disease-specific physiological aspects and surgical site situations.

Impact of sarcopenia on clinical outcomes in pediatric chronic liver disease post-liver transplantation: prevalence and implications

Aim

The purpose of this retrospective single-center study was to determine the frequency of sarcopenia and its association with mortality and other morbidities in children with chronic liver disease who had undergone liver transplantation.

Background

Sarcopenia, a muscle-wasting syndrome, is common in patients with advanced liver disease and is associated with increased morbidity and mortality. While sarcopenia in adults has been extensively studied, there is little information in this regard about children and adolescents with chronic liver diseases.

Methods

The study included 108 children and adolescents who had undergone liver transplantation. Sarcopenia was measured using skeletal muscle index at the third lumbar vertebral level and assessed using abdominal computed tomography imaging.

Results

The frequency of sarcopenia in the studied population was found to be 45.7%. Patients with sarcopenia were more likely to be male (P<0.0001), older (P<0.0001), and had lower height-for-age z-scores (P=0.012). Genetic/metabolic diseases were the most common underlying cause of sarcopenia in children. Except for a higher rate of transplant rejection in the sarcopenia group (P=0.035), there was no significant difference in mortality rates (P=0.688) or post-LT complications between the two groups. One year after LT, computed tomography-derived body composition parameters revealed no significant differences between children who survived and those who did not.

Conclusion

Our findings indicated a high frequency of sarcopenia in children with chronic liver disease, implying that more research is needed to better understand its impact on clinical outcomes in this population.

Preoperative low muscle mass and early postoperative outcomes in children undergoing living donor liver transplantation: A retrospective study

Low skeletal muscle mass may develop in children with end-stage liver disease, affecting postoperative outcomes. We retrospectively investigated whether preoperative low muscle mass was associated with early postoperative outcomes in pediatric patients undergoing living donor liver transplantation (LDLT). Electronic medical records of children (age below 12 y) who underwent LDLT between February 1, 2007, and January 31, 2018, were reviewed. The cross-sectional areas of psoas, quadratus lumborum, and erector spinae muscles at the level of fourth-fifth lumbar intervertebral disks were measured using abdominal CT images, divided by the square of the height and were added to obtain the total skeletal muscle index (TSMI). The patients were divided into two groups according to the median TSMI in the second quintile (1859.1 mm 2 /m 2 ). Complications in the early postoperative period (within 30 d after surgery) classified as Clavien-Dindo grade 3 or higher were considered major complications. Logistic regression analyses were performed to determine the association between preoperative low muscle mass and early postoperative outcomes. In the study population of 123 patients (median age, 14 mo; range, 8-38 mo) who underwent LDLT, 29% and 71% were classified in the low (mean TSMI, 1642.5 ± 187.0 mm 2 /m 2 ) and high (mean TSMI 2188.1 ± 273.5 mm 2 /m 2 ) muscle mass groups, respectively. The rates of major complications, mechanical ventilation >96 hours, intensive care unit stay >14 days, hospital stay >30 days, and in-hospital mortality were not significantly different between the 2 groups. Additionally, adverse outcomes according to pediatric end-stage liver disease scores and sex were not significantly different between the 2 groups. In conclusion, preoperative low muscle mass defined by TSMI was not associated with early postoperative outcomes in pediatric patients undergoing LDLT.

Physical frailty deteriorates after a 5-day dexamethasone course in children with acute lymphoblastic leukemia, results of a national prospective study

BACKGROUND

Dexamethasone is important in the treatment for pediatric acute lymphoblastic leukemia (ALL) but induces muscle atrophy with negative consequences for muscle mass, muscle strength, and functional abilities. The aim of this study was to establish the effect of a dexamethasone course on sarcopenia and physical frailty in children with ALL, and to explore prognostic factors.

METHODS

Patients with ALL aged 3-18 years were included during maintenance therapy. Patients had a sarcopenia/frailty assessment on the first day of (T1) and on the day after (T2) a 5-day dexamethasone course. Sarcopenia was defined as low muscle strength in combination with low muscle mass. Prefrailty and frailty were defined as having two or ≥three of the following components, respectively: low muscle mass, low muscle strength, fatigue, slow walking speed, and low physical activity. Chi-squared and paired t-tests were used to assess differences between T1 and T2. Logistic regression models were estimated to explore patient- and therapy-related prognostic factors for frailty on T2.

RESULTS

We included 105 patients, 61% were boys. Median age was 5.3 years (range: 3-18.8). At T1, sarcopenia, prefrailty, and frailty were observed in respectively 2.8%, 23.5%, and 4.2% of patients. At T2, the amount of patients with frailty had increased to 17.7% (p = 0.002), whereas the number of patients with sarcopenia and prefrailty remained similar. Higher ASMM (odds ratio [OR]: 0.49, 95% CI: 0.28-0.83), stronger handgrip strength (OR: 0.41, 95% CI: 0.22-0.77) and more physical activity minutes per day (OR: 0.98, 95% CI: 0.96-0.99) decreased the risk of frailty at T2. Slower walking performance (OR: 2, 95% CI: 1.2-3.39) increased the risk. Fatigue levels at T1 were not associated with frailty at T2.

CONCLUSION

Physical frailty increased strikingly after a 5-days dexamethasone course in children with ALL. Children with poor physical state at start of the dexamethasone course were more likely to be frail after the course.

Sarcopenia is associated with osteopenia and impaired quality of life in children with genetic intrahepatic cholestatic liver disease

BACKGROUND

Sarcopenia occurs in pediatric chronic liver disease, although the prevalence and contributing factors in genetic intrahepatic cholestasis are not well-described. The objective of this study was to measure muscle mass in school-aged children with genetic intrahepatic cholestasis and assess relationships between sarcopenia, clinical variables, and outcomes.

METHODS

Estimated skeletal muscle mass (eSMM) was calculated on dual-energy x-ray absorptiometry obtained in a Childhood Liver Disease Research Network study of children with bile acid synthesis disorders(BASD) alpha-1 antitrypsin deficiency (a1ATd), chronic intrahepatic cholestasis (CIC), and Alagille syndrome (ALGS). Relationships between eSMM, liver disease, and transplant-free survival were assessed.

RESULTS

eSMM was calculated in 127 participants (5-18 y): 12 BASD, 41 a1ATd, 33 CIC, and 41 ALGS. eSMM z-score was lower in CIC (-1.6 ± 1.3) and ALGS (-2.1 ± 1.0) than BASD (-0.1 ± 1.1) and a1ATd (-0.5 ± 0.8, p < 0.001). Sarcopenia (defined as eSMM z-score ≤- 2) was present in 33.3% of CIC and 41.5% of ALGS participants. eSMM correlated with bone mineral density in the 4 disease groups (r=0.52-0.55, p < 0.001-0.07), but not serum bile acids, bilirubin, aspartate aminotransferase/platelet ratio index, or clinically evident portal hypertension. Of the 2 patients who died (1 with sarcopenia) and 18 who underwent liver transplant (LT, 4 with sarcopenia), eSMM z-score did not predict transplant-free survival. eSMM z-score correlated with the Physical Pediatric Quality of Life Inventory score (r=0.38-0.53, p = 0.007-0.04) in CIC and a1ATd.

CONCLUSION

Severe sarcopenia occurs in some children with ALGS and CIC. The lack of correlation between eSMM and biochemical cholestasis suggests mechanisms beyond cholestasis contribute to sarcopenia. While sarcopenia did not predict transplant-free survival, LT and death were infrequent events. Future studies may define mechanisms of sarcopenia in genetic intrahepatic cholestasis.

Sarcopenia in Children With Wilms Tumor: A Marker of Undernutrition Which May Impact Adversely on Clinical Outcomes

The therapeutic approach to Wilms tumor (WT) is multidisciplinary and leads to significant patient impairment, increasing the risk of nutritional compromise and malnutrition. Children with cancer are vulnerable to sarcopenia which has been recognized as a negative impact of anticancer therapy. Recent studies have highlighted the reduction in the total psoas muscle area (TPMA) to be associated with a poor prognosis in many pediatric diseases, including cancer. This study aims to evaluate changes in the TPMA compartment during the treatment of children with WT. An observational, longitudinal, and retrospective study was undertaken in a single institution evaluating children (1 to 14 y, n=38) with WT between 2014 and 2020. TPMA was assessed by the analysis of previously collected, electronically stored computed tomography images of the abdomen obtained at 3 time points: diagnosis, preoperatively, and 1 year after surgery. For all patients, TPMA/age were calculated with a specific online calculator. Our data show a high incidence of sarcopenia (55.3%) at diagnosis which increased after 4 to 6 weeks of neoadjuvant chemotherapy (73.7%) and remained high (78.9%) 1 year after the surgical procedure. Using TPMA/age Z-score curves we have found significant and rapid muscle loss in children with WT, with little or no recovery in the study period.

Association Between Preoperative Sarcopenia and Early Postoperative Outcomes in Pediatric Patients Undergoing Total Correction of Tetralogy of Fallot: A Retrospective Cohort Study

OBJECTIVES

To identify the association between preoperative low muscle mass and early postoperative outcomes in pediatric patients undergoing total correction of tetralogy of Fallot (TOF).

DESIGN

A retrospective cohort study.

SETTING

A single university hospital in Seoul, South Korea.

PARTICIPANTS

Pediatric patients (≤3 years) who underwent total correction of TOF between May 2008 and February 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Cross-sectional areas of the pectoralis and erector spinae muscles were measured using preoperative chest computed tomography (CT) scans, and adjusted to body surface area to define muscle mass index. The patients were divided into sarcopenia, presarcopenia, and no sarcopenia groups based on cutoff values determined using the mean and SD of the muscle mass index in the third z-weight quintile. Of a total of 330 patients included in the final analysis, 13 were associated with the sarcopenia group, 57 in the presarcopenia group, and 260 in the no sarcopenia group. The sarcopenia group exhibited a higher incidence of major adverse events than the presarcopenia and no sarcopenia groups, respectively (38% v 25% v 18%; p = 0.033). Logistic regression analyses revealed that only younger age at the time of surgery was significantly associated with major adverse events (odds ratio 0.82; 95% CI 0.72-0.94, p = 0.003).

CONCLUSIONS

The incidence of sarcopenia, as assessed by preoperative chest CT, was low in pediatric patients undergoing total correction of TOF, and preoperative sarcopenia did not predict early postoperative major adverse events.

Physical function in children and adolescents pre- and 1-year post-liver transplant

BACKGROUND

Several studies describe poorer motor developmental motor outcomes post-liver transplant (LT) in younger children. Limited studies examine physical function in older children and adolescents pre- and post-LT.

METHODS

Retrospective review of standard of care physical function outcome measures pre- and 1-year post-LT in children ≥6 years at LT. Measures include: 6-minute walk test (6MWT), grip strength, Bruininks-Oseretsky Test of Motor Proficiency-2 (BOT-2) components, Physical Activity Questionnaire (PAQ), and Paediatric Quality of Life Multidimensional Fatigue Scale. Association of medical variables with outcomes was explored.

RESULTS

The study cohort included 23 (8 male, median (interquartile range) age 11.67 (8.25, 13.92) years at LT) participants. Top two primary diagnoses included biliary atresia (30.4%) and fulminant hepatic failure (21.7%). At 1-year post-LT, over one-third (36%) were overweight or obese. Compared with healthy norms, children had significantly lower pre-LT PAQ scores (p = .002), pre- and post-6MWT scores (p < .001) and post-LT BOT-2 strength and agility scores (p < .001). Pre-LT, lower balance scores were associated with abdominal distention/ascites (p = .009) and splenomegaly (p = .017). Lower pre-LT platelet count correlated with poorer balance (r = .532, p = .017) and lower strength and agility scores (r = .446, p = .043). Significant moderate inverse correlations were found between weight/body mass index z-scores and BOT-2 components. Post-LT children continue to demonstrate decreased levels of motor proficiency and functional capacity but report less fatigue and increased physical activity.

CONCLUSIONS

Older children and adolescents undergoing LT are at risk of decreased physical function, highlighting the need for pre- and post-LT rehabilitation to optimize long term outcomes.

Alagille syndrome: understanding the genotype-phenotype relationship and its potential therapeutic impact

INTRODUCTION

Alagille syndrome (ALGS) is an autosomal dominant, multisystem genetic disorder with wide phenotypic variability caused by mutations in the Notch signaling pathway, specifically from mutations in either the Jagged1 (JAG1) or NOTCH2 gene. The range of clinical features in ALGS can involve various organ systems including the liver, heart, eyes, skeleton, kidney, and vasculature. Despite the genetic mutations being well-defined, there is variable expressivity and individuals with the same mutation may have different clinical phenotypes.

AREAS COVERED

While no clear genotype-phenotype correlation has been identified in ALGS, this review will summarize what is currently known about the genotype-phenotype relationship and how this relationship influences the treatment of the multisystemic disorder. This review includes discussion of numerous studies which have focused on describing the genotype-phenotype relationship of different organ systems in ALGS as well as relevant basic science and population studies of ALGS. A thorough literature search was completed via the PubMed and National Library of Medicine GeneReviews databases including dates from 1969, when ALGS was first identified, to February 2023.

EXPERT OPINION

The genetics of ALGS are well defined; however, ongoing investigation to identify genotype-phenotype relationships as well as genetic modifiers as potential therapeutic targets is needed. Clinicians and patients alike would benefit from identification of a correlation to aid in diagnostic evaluation and management.

Decrease of Muscle Mass in Young Patients With Neuromuscular Disease: Assessment of Sarcopenia

BACKGROUND

Sarcopenia can be associated with the disease etiologies other than degenerative processes, such as neurologic disease including cerebral palsy, myelomeningocele, or Duchenne muscular dystrophy, even in children. Although the relationship between neurologic disease and scoliosis or ambulatory function is known, the mediators affecting scoliosis or gait function in these patients are unclear, an example might be sarcopenia. This study aimed to assess the degree of sarcopenia in young patients with neurologic diseases using computed tomography (CT), and analyze the correlation between sarcopenia and scoliosis or ambulatory function.

METHODS

Pediatric and young adult patients (≤ 25 years old) who underwent whole-spine or lower-extremity CT were retrospectively included. From bilateral psoas muscle areas (PMAs) at the L3 level, the psoas muscle z-score (PMz) and psoas muscle index [PMI = PMA/(L3 height)²] were calculated. The t-test, Fisher's exact test, and logistic regression analyses were performed.

RESULTS

A total of 121 patients (56 men, mean age 12.2 ± 3.7 years) were included with 79 neurologic and 42 non-neurologic diseases. Patients with neurologic diseases had lower PMz (P = 0.013) and PMI (P = 0.026) than patients without. In neurologic disease patients, severe scoliosis patients showed lower PMz (P < 0.001) and PMI (P = 0.001). Non-ambulatory patients (n = 42) showed lower BMI (β = 0.727, P < 0.001) and PMz (β = 0.547, P = 0.025). In non-ambulatory patients, patients with severe scoliosis also showed lower PMz (P < 0.001) and PMI (P = 0.004).

CONCLUSION

Patients with neurologic diseases could have sarcopenia even in young age. Psoas muscle volume was also associated with ambulatory function in these patients. Sarcopenia was more severe in severe scoliosis patients in the non-ambulatory subgroup.

The impact of low recipient weight [≤ 7kg] on long-term outcomes in 1078 pediatric living donor liver transplantations

BACKGROUND

infants who require liver transplantation represent a treatment challenge because chronic liver disease at this early age affects the child's growth and development during a critical phase. The aim is to compare demographics, operative data, and long-term outcomes according to recipient weight at the time of LDLT.

METHODS

This retrospective study included primary LDLT analyzed in 2 groups: BW ≤ 7 kg (n = 322) and BW > 7 kg (n = 756). A historical comparison between periods was also investigated.

RESULTS

BW ≤ 7 kg had significantly lower height/age and weight/age z-scores, with median PELD score of 19. Transfusion rates were higher in the BW ≤ 7 kg group (30.9 ml/kg versus 15.5 ml/kg, P < 0.001). Higher frequencies of PV complications were seen in the BW ≤ 7 kg cohort. HAT and retransplantation rates were similar. Those with BW ≤ 7 kg required longer ICU and hospital stays. Patient and graft survival were similar. Patient survival in BW≤ 7 kg was significantly better in the most recent period.

CONCLUSION

Malnutrition and advanced liver disease were more frequent in BW ≤ 7 kg. Despite increased rates of PVT and longer hospital stay, patient and graft long-term survival were similar between groups.

Perspectives on Sarcopenia as a Predictor for Outcomes in Pediatric Patients with Chronic Liver Disease

Sarcopenia, a pathologic deficiency of muscle mass and function, has emerged as an important secondary feature of many chronic disease states. For adults with end stage liver disease, there are multiple mechanisms which contribute to sarcopenia and its presence has proven to be an important predictor of morbidity and mortality. In children, there are only a limited number of reports which investigate the role of sarcopenia in liver disease. These studies, which are discussed and summarized in this review, report small, single-center analyses with dissimilar study cohorts and varying clinical definitions. Still, children meeting the study entry criteria have sarcopenia with a reported prevalence of 24-70%. When assessed, sarcopenia appears to be associated with more severe disease but is independent of the Pediatric End-Stage Liver Disease (PELD) score and does not correlate with age, gender, or traditional anthropometric measures such as weight, height, weight-for-height, or body mass index (BMI). While individual studies may identify sarcopenia as a statistically significant risk factor for certain post-transplant outcomes such as longer ICU stay, longer duration of intubation, repeat operation, development of serious infection, longer hospital stay, death, or long-term growth failure, such associations are not consistently replicated across studies. Finally, although various methods of muscle mass quantification are utilized, the most reported is the total psoas muscle surface area (tPMSA) on computed tomography. This method, along with others such as skeletal muscle area and skeletal muscle index, have had normative values recently defined and these collective efforts should enable researchers a common basis of comparison when delineating sarcopenia, and its impact, across various study populations in future investigations - including in children with liver disease.

Preoperative myopenia and myosteatosis and their impact on postoperative complications in children with inflammatory bowel disease

PURPOSE

To assess the severity of preoperative myopenia and myosteatosis in pediatric patients with inflammatory bowel disease (IBD) and examine their impact on postoperative complications.

METHODS

The subjects of this retrospective study were 30 pediatric patients with IBD (22 with ulcerative colitis (UC) and 8 with Crohn's disease (CD)) and 67 age-matched controls. Preoperative body mass index (BMI), psoas muscle index (PMI), and intramuscular adipose tissue content were compared between the patient groups, to investigate their association with postoperative complications.

RESULTS

BMI and PMI were significantly lower in the IBD patients than in the controls (p < 0.0001, p < 0.0001, respectively). CD was associated with significantly lower BMI and PMI (p = 0.01, p = 0.01, respectively) than UC. Intramuscular adipose tissue content was comparable between the IBD patients and the controls and between the UC and CD patients. There were no significant differences among the three indices in relation to the presence or absence of postoperative complications in patients with IBD. When limited to surgical site infection (SSI), only PMI was significantly lower in the patients with SSI than in those without SSI (p = 0.04).

CONCLUSIONS

Although BMI and PMI were lower preoperatively in pediatric IBD patients than in controls, only myopenia seemed to affect the development of SSI.

Sarcopenia prevalence in pediatric intestinal transplant recipients: Implications on post-transplant outcomes

BACKGROUND

Sarcopenia has been associated with poor surgical outcomes but has not been studied in pediatric intestinal transplantation. We aimed to determine sarcopenia prevalence in intestinal transplant recipients and the association of sarcopenia with outcomes.

METHODS

We performed a cross-sectional retrospective chart review of intestinal transplant recipients from 2000-present. We estimated total psoas muscle area (tPMA) at L3-L4 and L4-L5 from computed tomography scans prior to or in the immediate peri-operative period. Sarcopenia was defined by tPMA below the 5^th percentile for age and sex. We built a Cox-proportional hazards model to determine the association between sarcopenia and patient and graft survival.

RESULTS

Of the 56 intestinal transplant recipients included, 36 (64%) were sarcopenic. Graft survival was 79% at one year and 59% at five years. Overall patient survival was 86% at one year and 76% at five years. Peri-transplant sarcopenia was associated with improved graft survival (Hazard ratio 0.42, 95% confidence interval: 0.20-0.88) but not overall survival (Hazard ratio 0.47, 95% confidence interval: 0.19-1.20).

CONCLUSIONS

In this first report of sarcopenia in pediatric intestinal transplant, we found a high sarcopenia prevalence without an association with worse outcomes. The potential improved graft survival in sarcopenic patients along with underlying mechanisms warrant further exploration.

Sarcopenia in Children with Solid Organ Tumors: An Instrumental Era

Sarcopenia has recently been studied in both adults and children and was found to be a prognostic marker for adverse outcome in a variety of patient groups. Our research showed that sarcopenia is a relevant marker in predicting outcome in children with solid organ tumors, such as hepatoblastoma and neuroblastoma. This was especially true in very ill, high-risk groups. Children with cancer have a higher likelihood of ongoing loss of skeletal muscle mass due to a mismatch in energy intake and expenditure. Additionally, the effects of cancer therapy, hormonal alterations, chronic inflammation, multi-organ dysfunction, and a hypermetabolic state all contribute to a loss of skeletal muscle mass. Sarcopenia seems to be able to pinpoint this waste to a high degree in a new and objective way, making it an additional tool in predicting and improving outcome in children. This article focuses on the current state of sarcopenia in children with solid organ tumors. It details the pathophysiological mechanisms behind sarcopenia, highlighting the technical features of the available methods for measuring muscle mass, strength, and function, including artificial intelligence (AI)-based techniques. It also reviews the latest research on sarcopenia in children, focusing on children with solid organ tumors.

Malnutrition in Biliary Atresia: Assessment, Management, and Outcomes

Children with biliary atresia (BA), particularly infants, are at high risk for malnutrition attributed to a multitude of factors, including poor oral intake and intolerance of enteral feeding, fat malabsorption, abnormal nutrient metabolism, and increased caloric demand. Malnutrition and sarcopenia negatively impact outcomes in BA, leading to higher pretransplant and posttransplant morbidity and mortality. This review summarizes factors contributing to nutritional deficiencies in BA and offers an organized approach to the assessment and management of malnutrition in this vulnerable population.

Multidisciplinary Management of Alagille Syndrome

Alagille syndrome (ALGS) is an autosomal dominant disorder characterized by involvement of various organ systems. It predominantly affects the liver, skeleton, heart, kidneys, eyes and major blood vessels. With myriads of presentations across different age groups, ALGS is usually suspected in infants presenting with high gamma glutamyl transpeptidase cholestasis and/or congenital heart disease. In children it may present with decompensated cirrhosis, intellectual disability or short stature, and in adults vascular events like stroke or ruptured berry aneurysm are more commonly noted. Liver transplantation (LT) is indicated in children with cholestasis progressing to cirrhosis with decompensation. Other indications for LT include intractable pruritus, recurrent fractures, hepatocellular carcinoma and disfiguring xanthomas. Due to an increased risk of renal impairment noted in ALGS, these patients would require optimized renal sparing immunosuppression in the post-transplant period. As the systemic manifestations of ALGS are protean and a wider spectrum is being increasingly elucidated, a multidisciplinary team needs to be involved in managing these patients. Moreover, many basic-science and clinical questions especially with regard to its presentation and management remain unanswered. The aim of this review is to provide updated insights into the management of the multi-system involvement of ALGS.

Sarcopenia in children with chronic liver disease: Prevalence and impact on liver transplant outcomes

Sarcopenia is a clinical condition characterized by a reduction in muscle mass, which typically affects adult patients; however, it has recently been recognized in pediatric literature. Few studies in children with chronic liver disease (CLD) undergoing liver transplantation (LT) have investigated the role of sarcopenia, with controversial results. The aim of our study was to assess the prevalence and impact of sarcopenia among children with CLD who are candidates for LT. We conducted a retrospective, single-center study at Bambino Gesù Children's Hospital (Rome, Italy) from July 2016 to July 2021, evaluating all children (0-16 years old) with CLD listed for LT with an abdomen computed tomography imaging available before LT. The total psoas muscle surface area (t-PMSA) was defined as the sum of left and right psoas muscle surface area measured at L4-L5 on axial images. The t-PMSA z-score was calculated according to reference data, and sarcopenia was defined as a t-PMSA z-score of ≤-2 (1-16 years) or a psoas muscle index [PMI; PMI = t-PMSA/(100 × BSA)] of <50th percentile of the population examined (<1 year). Clinical, laboratory, and LT outcome data were collected from all the patients with CLD. 27 out 48 (56%) of the patients aged 1-16 years were sarcopenic. No differences were noted in anthropometrics, nutritional support, liver function tests, model for ESLD (MELD), or pediatric ESLD (PELD) scores between patients with and without sarcopenia. The former showed a higher prevalence of respiratory complications (66.7% vs. 42.1%) and need for inotropes (40.7% vs. 10.8%) after LT. Among patients aged 0-1 years (n: 36), those with reduced muscle mass (50%) had a longer hospitalization time (44 vs. 24 days) and higher incidences of multi-organ failure syndrome (38.9% vs. 0%) and intensive care unit-related infections (61.1% vs. 27.8%) compared to those with greater muscle mass. t-PMSA and PMI were statistically significant predictors of LT outcomes. Sarcopenia is a reliable index of frailty in children with CLD, as its presence is associated with the risk of a more challenging LT. Future studies will have to investigate the functional aspects of sarcopenia and conceive preventive measures of muscle wasting in CLD patients.

Impact of muscle mass on the prognosis of liver transplantation for infants with biliary atresia

BACKGROUND

Sarcopenia in adult cirrhotic patients is associated with increased morbidity and mortality whereas in children it is still being studied. Anthropometric variables in cirrhotic children are not reliable for assessing muscle mass as they may be altered by ascites, edema, and organomegaly. Measuring the area of the psoas showed good correlation with muscle mass in adults. We aimed to study in cirrhotic infants undergoing liver transplantation the association of the psoas area with liver transplant prognosis as well as with several analytical and anthropometric parameters used to evaluate nutritional status.

METHODS

Retrospective cohort of 29 infants with cirrhosis due to biliary atresia who underwent abdominal CT scan as a pre-transplant study. We measured the psoas muscle index (PMI) at L4-L5 since it best correlates with muscle mass in pediatric patients. As there are no validated cut-off points to define sarcopenia in children under one year of age, PMI was recorded as a continuous variable and correlated with different prognostic, clinical, and analytical variables. The SPSS 17.0 package was used for statistical analysis and a P < 0.05 was considered significant.

RESULTS

29 infants (10 boys, 19 girls) were studied. 62% were Caucasian and the rest were South American. The mean age at CT scan was 8.5 months (range 3-15 months). There was a negative correlation between PMI and days of admission prior to liver transplant, previous infections, and bone fractures. Among the analytical parameters, cholinesterase, albumin, and prealbumin correlated positively with PMI (P < 0.05). No relationship was observed with anthropometric parameters: weight, height, BMI, brachial perimeter, or bioimpedance. During surgery, patients with lower PMI had a greater need for plasma transfusion, and in the immediate postoperative period, there was a longer stay in intensive care, more days of mechanical ventilation, and more days of hospital admission (P < 0.05). On the contrary, no relationship was found with other complications: bleeding, re-interventions, biliary leaks, rejection, thrombosis, re-transplantation, or infections.

CONCLUSIONS

The decrease in muscle mass is associated with increased morbidity in infants with biliary atresia undergoing liver transplantation. Muscle mass in these patients cannot be adequately assessed with anthropometric measurements commonly used in the clinic.

Utility of Preoperative Computed Tomography-Based Body Metrics in Relation to Postoperative Complications in Pediatric Liver Transplantation Recipients

Computed tomography (CT)-derived body metrics such as skeletal muscle index (SMI), psoas muscle index (PMI), and subcutaneous fat area index (ScFI) are measurable components of sarcopenia, frailty, and nutrition. While these body metrics are advocated in adults for predicting postoperative outcomes after liver transplantation (LT), little is known about their value in pediatric populations. This study assessed the relation between preoperative CT-based body metrics and postoperative short-term outcomes in pediatric LT recipients. Patients aged 0-18 years who underwent a primary LT were retrospectively included (n = 101; median age 0.5 years; range 0.2-17.1). SMI, PMI, and ScFI were derived from preoperative axial CT slices. Postoperative outcomes and complications within 90 days were correlated with the CT-based body metrics. To classify postoperative infections, the Clavien-Dindo (CD) classification was used. Subgroup analyses were performed for age groups (<1, 1-10, and >10 years old). An optimal threshold for test performance was defined using Youden's J-statistic and receiver operating characteristic curve as appropriate. ScFI was significantly (P = 0.001) correlated with moderate to severe postoperative infections (CD grade 3-5) in children aged <1 year, with the optimal ScFI threshold being ≤27.1 cm2 /m2 (sensitivity 80.4% and specificity 77.8%). A weak negative correlation between SMI and the total duration of hospital stay (R = -0.3; P = 0.01) and intensive care unit (ICU) stay (R = -0.3; P = 0.01) was observed in children aged <1 year. No other associations between CT-based body metrics and postoperative outcomes were shown. In children aged <1 year with cirrhotic liver disease undergoing LT, preoperative CT-based body metrics were correlated with moderate to severe postoperative infections (ScFI) and with longer duration of hospital and ICU stay (SMI), and thus can be considered important tools for pre-LT risk assessment.

Malnutrition in Pediatric Chronic Cholestatic Disease: An Up-to-Date Overview

Despite recent advances, the causes of and effective therapies for pediatric chronic cholestatic diseases remain elusive, and many patients progress to liver failure and need liver transplantation. Malnutrition is a common complication in these patients and is a well-recognized, tremendous challenge for the clinician. We undertook a narrative review of both recent and relevant older literature, published during the last 20 years, for studies linking nutrition to pediatric chronic cholestasis. The collected data confirm that malnutrition and failure to thrive are associated with increased risks of morbidity and mortality, and they also affect the outcomes of liver transplantation, including long-term survival. Malnutrition in children with chronic liver disease is multifactorial and with multiple potential nutritional deficiencies. To improve life expectancy and the quality of life, patients require careful assessments and appropriate management of their nutritional statuses by multidisciplinary teams, which can identify and/or prevent specific deficiencies and initiate appropriate interventions. Solutions available for the clinical management of these children in general, as well as those directed to specific etiologies, are summarized. We particularly focus on fat-soluble vitamin deficiency and malnutrition due to fat malabsorption. Supplemental feeding, including medium-chain triglycerides, essential fatty acids, branched-chain amino acids, and the extra calories needed to overcome the consequences of anorexia and high energy requirements, is reviewed. Future studies should address the need for further improving commercially available and nutritionally complete infant milk formulae for the dietary management of this fragile category of patients. The aid of a specialist dietitian, educational training regarding nutritional guidelines for stakeholders, and improving family nutritional health literacy appear essential.