Metabolic syndrome after pediatric liver transplantation

Fibrosis and steatosis of the liver graft: Are non-invasive tests useful? A short review

As life expectancy of liver transplanted patients improves, new questions are arising to avoid progressive graft loss. The spectrum of chronic inflammation and fibrosis are known to be important triggers in the alteration of graft function. Liver biopsy remains the gold standard to better understand progressive, normal, and abnormal histological modifications of the graft. In parallel, the interest for metabolic steatosis development in post-transplantation is also growing. Long-term survival of these patients involves the management of comorbidities including metabolic syndrome and cardiovascular diseases. Early detection of altered graft parenchyma, and monitoring of its evolution are undoubtedly essential. Non-invasive methods including transient elastography and fibrosis biomarkers are attractive tools to avoid drawbacks and complications of liver biopsy. Accuracy of these methods are well-known in a pre-transplantation setting, but evidence is lacking in post-transplantation setting. We review current knowledge of progressive liver fibrosis and steatosis development after transplantation and non-invasive methods of their assessment.

Long-term Outcome of Pediatric Liver Transplant Recipients Who Have Reached Adulthood: A Single-center Experience

BACKGROUND

As long-term survival of pediatric liver transplant recipients increases, the assessment of physical, psychological, and social well-being becomes more important.

METHODS

In this retrospective analysis, 120 young adult patients (age ≥18 y) who underwent liver transplantation in childhood were studied. Patients with ideal outcome were defined as patients with perfect graft function, with no complications from the immunosuppressive medication, no late retransplantation, and no steroid treatment. Also, the patients' drug adherence and their psychosocial situation were assessed.

RESULTS

After a median follow-up of 19 y, only 16.7% of the patients (mean age: 26.5 y) were considered patients with ideal outcome. The main reasons precluding ideal outcome were chronic kidney disease (38.3%), elevated liver enzymes (33.3%), and arterial hypertension (31.7%). Ideal outcome decreased over time from 54% to 42%, 26%, and 8% at 10-, 15-, 20-, and 25-y follow-up, respectively. Reduced drug adherence was noted in 24.8% of patients and associated with a significantly higher prevalence of donor-specific antibodies class II ( P  = 0.015), elevated transaminases ( P  = 0.010), and chronic rejection ( P  < 0.001). Also, 15% of patients had a psychiatric disease, mainly depression.

CONCLUSIONS

The morbidity of young adults who underwent liver transplantation as children was high and increased over time. The majority developed complications from immunosuppression or chronic graft dysfunction. More than 1 in 7 patients had a psychiatric disease and 1 in 4 was not perfectly drug adherent. Therefore, immunosuppressive treatment and psychological care should be optimized for these particularly vulnerable patients.

Markers of obesity in Danish pediatric liver transplantation recipients

BACKGROUND

Long-time survivors of pediatric liver transplantation have an increased incidence of the metabolic syndrome. Adult recipients have an increased risk of post-transplantation obesity; however, pediatric data are limited.

METHODS

The study included 42 recipients of pediatric liver transplantation in Denmark, transplanted between 1990 and 2014. The study participants were examined with anthropometric measures, dual-energy X-ray scans and blood samples. From the anthropometric measures, body mass index (BMI) and BMI standard deviation score (SDS) were calculated. From the dual-energy X-ray scans, fat percent was assessed, and body fat mass index (BFMI) was calculated.

RESULTS

The median age was 17.4 years (range 4.1-38.9) at the time of the study, and the median time since transplantation was 8.5 years (range 0.4-23.9). The prevalence of overweight and obesity was 31.0% based on BMI SDS (age below 18) and BMI (age 18 and above). When compared to the participants with normal weight, the participants with overweight and obesity had a higher BFMI (9.29 vs 5.57 kg/m² , p < .001) and fat percent (38.35% vs 29.50%, p = .006). They had higher levels of total cholesterol (4.3 vs 3.6 mmol/L, p = .023) and low-density lipoprotein (2.5 vs 1.7, p = .015), and had had longer time since transplantation (15.6 vs 8.5 years respectively, p = .045).

CONCLUSIONS

Long-time survivors of pediatric liver transplantation have a higher BMI or BMI SDS than the general pediatric population. The obesity is characterized by a higher BFMI, fat percent, and cholesterols levels, when compared to recipients without overweight or obesity.

METABOLIC AND NUTRITIONAL REPERCUSSIONS OF LIVER DISEASE ON CHILDREN: HOW TO MINIMIZE THEM?

Objective:

To describe the metabolic and nutritional repercussions of chronic liver disease (CLD), proposing strategies that optimize nutritional therapy in the pre- and post-liver transplantation (LT) period, in order to promote favorable clinical outcomes and adequate growth and development, respectively.

Data sources:

Bibliographic search in the PubMed, Lilacs and SciELO databases of the last 12 years, in English and Portuguese; target population: children from early childhood to adolescence; keywords in Portuguese and their correlates in English: “Liver Transplant,” “Biliary Atresia,” “Nutrition Therapy,” “Nutritional Status,” and “Child”; in addition to Boolean logics “and” and “or,” and the manual search of articles.

Data synthesis:

Malnutrition in children with CLD is a very common condition and an important risk factor for morbidity and mortality. There is an increase in energy and protein demand, as well as difficulties in the absorption of carbohydrates, lipids and micronutrients such as fat-soluble vitamins and some minerals. An increase in the supply of energy, carbohydrates and proteins and micronutrients, especially fat-soluble vitamins, iron, zinc and calcium, is suggested, except in cases of hepatic encephalopathy (this restriction is indicated for a short period).

Conclusions:

Based on metabolic changes and anthropometric and body composition monitoring, a treatment plan should be developed, following the nutritional recommendations available, in order to minimize the negative impact of malnutrition on clinical outcomes during and after LT.

Metabolic syndrome and liver disease in the era of bariatric surgery: What you need to know!

Metabolic syndrome (MS) is defined as the constellation of obesity, insulin resistance, high serum triglycerides, low high-density lipoprotein cholesterol, and high blood pressure. It increasingly affects more and more people and progressively evolves into a serious issue with widespread healthcare, cost, and quality of life associated consequences. MS is associated with increased morbidity and mortality due to cardiovascular or chronic liver disease. Conservative treatment, which includes diet, exercise, and antidiabetic agents, is the mainstay of treatment, but depends on patient compliance to medical treatment and adherence to lifestyle modification recommendations. Bariatric surgery has recently emerged as an appropriate alternative treatment with promising long-term results. Sleeve gastrectomy and Roux-en-Y gastric bypass constitute the most commonly performed procedures and have been proven both cost-effective and safe with low complication rates. Liver transplantation is the only definitive treatment for end-stage liver disease and its utilization in patients with non-alcoholic steatohepatitis has increased more than fivefold over the past 15 years. In this review, we summarize current state of evidence on the surgical treatment of MS.

Etiology of liver dysfunction after liver transplantation in children with metabolic disorders

AIM

It has been reported that the long-term outcome for children with metabolic disorders after liver transplantation (LT) is excellent. However, there are several reports citing LT patients with metabolic disorders developing liver dysfunction early after LT. We examined the pathogenesis of liver dysfunction observed after LT in recipients with metabolic disorders at the National Center for Child Health and Development.

METHODS

Of 106 children (aged <18 years) with metabolic disorders who underwent LT at our center, 36 patients who underwent liver biopsy within 60 days after LT were enrolled. The underlying diseases were urea cycle disorders (14 patients), methylmalonic acidemia (11 cases), Wilson's disease (3 patients), mitochondrial hepatopathy (3 patients), and others (5 patients). The median age was 1 year 2 months at LT. The reasons for biopsy were liver dysfunction (31 patients) and ascites (5 patients).

RESULTS

The main findings of graft liver biopsy were diffuse steatosis (21 patients), rejection (8 patients), infection (3 patients), and others (4 patients). Of 21 patients who received graft biopsy showing steatosis, all the donor livers originally showed no steatosis or only mild steatosis. The liver function improved immediately after biopsy in 18 of 21 patients that showed diffuse steatosis.

CONCLUSIONS

The major cause of liver dysfunction after LT in recipients with metabolic disorders was steatosis and the risk of rejection was low. It is important to take a liver biopsy and examine the cause of liver dysfunction to avoid administration of excess immunosuppressant, and select the right therapy for recipients with metabolic disorders.

Healthy Body Weights With Corticosteroid-free Immunosuppression Is the Best Predictor of Cardiovascular Health in Children After Liver Transplantation

INTRODUCTION

Cardiometabolic dysregulation (CMD) influences morbidity and mortality risk in adults post-liver transplantation (LTx). CMD is reported in 10% to 25% of pediatric LTx recipients, but no information regarding the longitudinal expression of CMD is available. The study objective was to examine the longitudinal expression of CMD and associations with body composition and growth in children post-LTx.

METHODS

A retrospective review was conducted in youth (34 F/30 M) who underwent LTx between 1994 and 2015 at the Stollery Children's Hospital. Primary outcomes included serum markers of CMD (insulin, glucose, hemoglobin A1C [A1C], homeostasis model assessment for insulin resistance [abnormal >3], lipid panel triglycerides, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol) and systolic/diastolic blood pressure (BP: absolute/z scores).

RESULTS

Mean (±SD) age, weight z, height z, body mass index z was 9.7 ± 3.4 years (3.5-17.9), 0.26 ± 1.03, 0.017 ± 1.2, and 0.41 ± 1.05, respectively. The majority of children had percentage fat mass, percentage fat-free mass within normal reference ranges. Systolic/diastolic BP was within healthy references ranges in 83.1% and 93.5% of children, respectively. Serum insulin (83.4%) and high-density lipoprotein-cholesterol (43.9%) concentrations were low, with abnormal findings of other laboratory markers found in <5% of participants. Abnormal findings for metabolic parameters were independent of weight z, body mass index z, fat mass, and corticosteroids but were positively related to child's age (>9.7 years) and fat-free mass (total, arms). Insulin levels decreased significantly in the first 4 years post-LTx, but no changes in lipid panel, A1C and glucose were noted over 10 years.

CONCLUSIONS

Pediatric LTx recipients with healthy body weights and corticosteroid-free immunosuppression have a low expression of CMD over 10 years.

Cardiovascular Risk Assessment in Pediatric Liver Transplant Patients

OBJECTIVES

Cardiovascular (CV) diseases play a leading role in the mortality of adult liver transplant (LT) recipients. However, data regarding CV risk factors in children after LT remain sparse. The present study assessed the presence of CV risk factors and signs of CV impairment in LT children.

METHODS

A total of 42 LT recipients (21 men, age 9.93 ± 3.57 years) were studied. Body composition [body mass index standard deviation score, percentage of body fat (by bioimpedance analysis)], lipid profiles, glycemic control, blood pressure, and arterial stiffness [assessed by aortic pulse wave velocity (PWV)] were evaluated. The effect of different treatment modalities [tacrolimus (TAC) (n = 30) or cyclosporine (CyA) (n = 11)] was also analyzed.

RESULTS

Almost 18% of children were overweight or obese. Patients on TAC had a significantly higher body fat mass and percentage of body fat compared with the CyA group (P < 0.02). Borderline to high lipid values were present in 40% of patients. Children on CyA had higher serum cholesterol levels compared to TAC (P < 0.004). Nineteen percent of patients had hypertension. Half of the patients had glomerular filtration rate values <90 mL/min/1.73 m, whereas PWV values were above the 95th percentile in 12%.

CONCLUSIONS

Increased body fat, chronic kidney disease, high lipid content, hypertension, and increased arterial stiffness are already present and are in part related to the type of immunosuppression regimen in LT children >5 years following transplantation. Long-term follow-up is needed to evaluate their impact on CV health and survival.

Diet and Exercise in Pediatric Liver Transplant Recipients: Behaviors and Association With Metabolic Syndrome

OBJECTIVE

The aim of the study is to analyze the impact of physical activity and eating behaviors on precursors of cardiovascular disease-including overweight/obesity, hypertension, low high-density lipoprotein, and impaired glucose tolerance-in pediatric liver transplant (LT) recipients and matched controls.

METHOD

Cross-sectional study of pediatric LT recipients 8 to 30 years, matched to controls from the National Health and Nutrition Examination Survey. Dietary intake assessed with 24-hour recall. Physical activity assessed by standardized questionnaires. LT recipients ≥12 years completed a confidential survey on alcohol consumption.

RESULTS

LT recipients (n = 90) were 0.9 to 24.7 years post-transplant. LT recipients and controls were equally likely to consume excess carbohydrates (32% vs 34%) and sugar, per age- and gender-specific recommended dietary intake guidelines. LT recipients spent more hours sedentary or on the computer daily and fewer days each week physically active for >60 minutes than controls. More overweight/obese LT recipients spent 3+ hours at the computer than non-overweight LT recipients (49% vs 27%; P = 0.02). Normal weight LT recipients spent more days doing vigorous activity each week (median 5 days, interquartile range 2-6) than did the overweight/obese LT recipients (median 3 days, interquartile range 2-4; P = 0.01). Among LT recipients, neither dietary intake nor physical activity were consistently associated with measures of hypertension, glucose intolerance, or dyslipidemia. Among LT adolescents and young adults (n = 38), 36% reported ever consuming alcohol; 38% of these reported significant alcohol consumption by frequency or quantity.

CONCLUSIONS

Additional counseling during routine post-LT care on the importance of physical activity and healthy diet may be useful. However, it is unlikely that these factors alone explain the increased prevalence of metabolic syndrome components in pediatric LT recipients.

Risk markers for later cardiovascular diseases in liver-transplanted children and adolescents

BACKGROUND

Increased risk of cardiovascular diseases is well described after adult liver transplantation, whereas the risk in the pediatric population still is discussed. The aim of this study was to investigate the prevalence of metabolic syndrome in pediatric liver transplant recipients and whether measurements of carotid intima media thickness and pulse wave velocity were increased compared to healthy controls.

METHODS

We included 42 pediatric liver transplantation recipients and examined them for markers of metabolic syndrome, liver fibrosis measured by shear wave velocity, body fat measured by DXA scans and carotid intima-media thickness, and pulse wave velocity (n = 41 for the carotid scans). The ultrasound measurements of carotid intima-media thickness and pulse wave velocity were also conducted on 82 healthy children and adolescents matched on height and age, respectively.

RESULTS

Participants had a median age of 13.03 years, and median time since transplantation was 8.54 years. Compared to healthy controls, liver-transplanted patients had significantly increased intima-media thickness measurements in both control groups whereas there was no significant difference with regard to pulse wave velocity. Two patients (6.25%) were diagnosed with metabolic syndrome. Within the group of liver-transplanted pediatric patients, only elevated body mass index was associated with elevated carotid intima-media thickness measurement. Elevated pulse wave velocity was only associated with abdominal obesity. Factors not significantly correlated with either were age, sex, metabolic syndrome, hyperglycemia, triglycerides, years since transplantation, fibrosis of the liver, body fat content, smoking habits, HDL cholesterol levels, hypertension, and mono-drug versus multi-drug therapies.

CONCLUSION

Pediatric liver transplant recipients do have an increased risk of increased carotid intima-media thickness.

Hepatic steatosis after pediatric liver transplant

Hepatic steatosis develops after liver transplantation (LT) in 30% of adults, and nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in nontransplanted children. However, posttransplant steatosis has been minimally studied in pediatric LT recipients. We explored the prevalence, persistence, and association with chronic liver damage of hepatic steatosis in these children. In this single-center study of pediatric patients transplanted 1988-2015 (n = 318), 31% of those with any posttransplant biopsy (n = 271) had ≥ 1 biopsy with steatosis. Median time from transplant to first biopsy with steatosis was 0.8 months (interquartile range [IQR], 0.3-6.5 months) and to last biopsy with steatosis was 5.5 months (IQR, 1.0-24.5 months); 85% of patients with steatosis also had for-cause biopsies without steatosis. All available for-cause biopsies were re-evaluated (n = 104). Of 9 biopsies that could be interpreted as nonalcoholic steatohepatitis (NASH)/borderline NASH, with steatosis plus inflammation or ballooning, 8 also had features of cholestasis or rejection. Among 70 patients with surveillance biopsies 3.6-20.0 years after transplant, only 1 overweight adolescent had a biopsy with NAFLD (grade 1 steatosis, mild inflammation, no ballooning or fibrosis)-despite a 30% prevalence of overweight/obesity in the cohort and 27% with steatosis on previous for-cause biopsy. Steatosis on preceding for-cause biopsy was not associated with portal (P = 0.49) or perivenular fibrosis (P = 0.85) on surveillance biopsy. Hepatic steatosis commonly develops early after transplant in children and adolescents, but it rarely persists. Biopsies that did have steatosis with NASH characteristics were all for-cause, mostly in patients with NAFLD risk factors and/or confounding causes of liver damage. Prospective studies that follow children into adulthood will be needed to evaluate if and when hepatic steatosis presents a longterm risk for pediatric LT recipients. Liver Transplantation 23 957-967 2017 AASLD.

Metabolic Syndrome Components After Pediatric Liver Transplantation: Prevalence and the Impact of Obesity and Immunosuppression

Metabolic syndrome is associated with long-term morbidity and mortality after adult liver transplantation (LT). Whether pediatric LT recipients have a higher prevalence of metabolic syndrome remains controversial. In a cross-sectional study, we evaluated pediatric LT recipients aged 8-30 years using National Health and Nutrition Examination Survey (NHANES) protocols. LT recipients were matched by gender, race/ethnicity, and age with controls from NHANES. Pediatric LT recipients (n = 83), after adjusting for overweight/obesity and glucocorticoid use, had increased prevalence of prehypertension and hypertension, impaired glucose tolerance (IGT; 2-h glucose after oral glucose tolerance test ≥140 mg/dL), and low high-density lipoprotein compared to matched NHANES controls (n = 235) despite a lower prevalence of overweight/obesity. Among LT recipients, the adjusted odds of IGT doubled for every 7.5 years taking calcineurin inhibitors (odds ratio = 2.10, 95% confidence interval 1.06-4.17 per 7.5 years taking calcineurin inhibitors, p = 0.03). Among all subjects with IGT, LT recipients had a lower prevalence of overweight/obesity and less insulin resistance (homeostatic model assessment of insulin resistance) than did controls with IGT. Among normal weight subjects, LT recipients were significantly more likely than controls to have prehypertension/hypertension, IGT, low high-density lipoprotein, and metabolic syndrome. Pediatric LT recipients have unique metabolic syndrome profiles and risk factors and will require tailored screening and management protocols.

Subclinical cardiovascular changes in pediatric solid organ transplant recipients: A systematic review and meta-analysis

CV disease is a major cause of morbidity and mortality following solid organ transplantation in adults. While the prevalence of multiple cardiometabolic risk factors is increased in pediatric solid organ transplant recipients, it is not clear whether they have subclinical CV changes. cIMT, central pWV, and CAC are indicative of subclinical CV disease, and, in adults, predict future CV events. The objective of this systematic review and meta-analysis was to investigate the prevalence of subclinical CV changes, as measured by cIMT, pWV, and CAC among pediatric solid organ transplant recipients. We searched MEDLINE(®) and EMBASE and conducted meta-analysis for studies that evaluated cIMT, central pWV, and CAC among pediatric solid organ transplant recipients (kidney, lung, intestine and liver). The search identified nine eligible studies that included a total of 259 patients and 685 healthy controls. Eight studies reported on kidney transplant recipients and one study on a combined cohort of kidney and liver transplant recipients. The mean cIMT of transplant recipients was significantly higher than that of healthy controls (mean difference = 0.05 mm, 95% CI 0.02-0.07; p < 0.0001) with an estimated pooled prevalence of elevated cIMT of 56.0% (95% CI 17.0-95.0). The one study that assessed pWV showed increased vascular stiffness in transplant recipients compared to healthy controls. No studies assessing for CAC were found. There were limited data regarding subclinical CV disease following pediatric solid organ transplantation. In conclusion, kidney transplantation in childhood is associated with a higher prevalence of subclinical CV changes compared to healthy children. Longitudinal studies are needed to determine whether children have increased CV morbidity and mortality after transplantation.

Lipid profile and cardiovascular risk factors in pediatric liver transplant recipients

Cardiovascular diseases induce long-term morbidity and mortality of adult LT recipients. The aim of this retrospective study was to assess CVRF, lipid abnormalities, and atherosclerosis (appraised by c-IMT), more than 10 yr after pediatric LT. Thirty-one children who underwent LT between December 1990 and December 2000 were included. Median age at LT was 14 months (range 4-64), and median follow-up after LT was 11.9 yr (range 9.0-17.3). In our cohort, obesity (9.7%) and treated hypertension (9.7%) were rare. None of the patients was smoker or diabetic. High TC and TG were both observed in 6.5% of the patients. The mean c-IMT for male patients was 1.22 ± 1.55 and 1.58 ± 1.23 mm in female patients. Seven patients (22%) had a mean c-IMT above +2 s.d. Values below the 5th percentile were noted for LDL-cholesterol (58.1%), HDL-cholesterol (25.8%), apolipoprotein B (40%), and apolipoprotein A1 (20%). LDL-cholesterol and apolipoprotein B levels were significantly lower in patients treated by tacrolimus in comparison with CsA (p < 0.05). In conclusion, our results suggest that pediatric LT patients do not present significant CVRF; moreover, instead of hyperlipidemia, hypocholesterolemia (LDL-C) is frequent and immunosuppressive therapy is probably the cause.