Non-alcoholic fatty liver disease; a part of the metabolic syndrome in the renal transplant recipient and possible cause of an allograft dysfunction

Association of metabolic dysfunction-associated steatotic liver disease with erosive esophagitis development: a longitudinal observational study

BACKGROUND AND AIM

Although erosive esophagitis (EE) is associated with fatty liver and metabolic dysregulation, the association between EE and metabolic dysfunction-associated steatotic liver disease (MASLD) remains unclear. Thus, this study aimed to investigate the longitudinal association between MASLD and EE.

METHODS

We included 1578 patients without EE at baseline who underwent more than two health checkups over 2 years. Generalized estimation equations were used to analyze associations between MASLD and EE according to repeated measures at baseline and most recent stages.

RESULTS

EE development rates in men and women were 14.5% and 7.2%, respectively. After adjusting for lifestyle habits, the odds ratios of MASLD for EE development in men and women were 1.907 (95% confidence interval [CI]: 1.289-2.832, P < 0.005) and 1.483 (95% CI: 0.783-2.811, P = 0.227), respectively. In the subgroup analysis, after adjusting for lifestyle habits, among men and women aged ≥50 years with more than three MASLD components, the odds ratios for EE development were 2.408 (95% CI: 1.505-3.855, P < 0.001) and 2.148 (95% CI: 1.093-4.221, P < 0.05), respectively. After adjusting for various factors, the significant risk factors for EE development were different between men and women.

CONCLUSION

The influence of MASLD and other factors on EE development differed by sex and age. Particularly, patients aged ≥50 years with MASLD and with an increased number of MASLD components should be considered at increased risk for EE.

Metabolic dysfunction-associated fatty liver disease (MAFLD) and advanced liver fibrosis among hemodialysis patients in a multiethnic urban population in Malaysia

BACKGROUND

Metabolic-dysfunction-associated fatty liver disease (MAFLD) and end stage kidney disease (ESKD) are complications of the metabolic syndrome. Our aim is to study the prevalence of MAFLD and advanced liver fibrosis and the associated factors among hemodialysis patients in a multiracial urban population in Malaysia.

METHODS

A cross-sectional study of hemodialysis patients from 10 hemodialysis centers was used. FibroTouch examination was performed on all patients. Fatty liver was diagnosed based on ultrasound attenuation parameter ≥248 dB/m while advanced liver fibrosis was diagnosed based on liver stiffness measurement ≥10 kPa.

RESULTS

This study included 447 hemodialysis patients (median age 59 [50-67], male 55%, Chinese 61%, Malay 20%, Indian 18%). Dialysis vintage was 49 (22-93) months. The prevalence of MAFLD was 43.4%. Independent factors associated with MAFLD were elevated waist circumference (aOR = 10.1, 95% CI = 5.3-19.4, p < 0.001), normal platelet count (aOR = 3.1, 95% CI = 1.3-7.3, p < 0.05), low HDL cholesterol (aOR = 2.3, 95% CI = 1.3-4.2, p < 0.01), elevated fasting blood sugar (aOR = 2.3, 95% CI = 1.3-3.8, p < 0.01), elevated hsCRP (aOR = 2.2, 95% CI = 1.2-4.0, p < 0.01), and advanced liver fibrosis (aOR = 3.0, 95% CI = 1.6-5.6, p < 0.001). The prevalence of advanced liver fibrosis was 25.5%. Independent factors associated with advanced liver fibrosis were male gender (aOR = 1.8, 95% CI = 1.0-3.0, p < 0.05), elevated waist circumference (aOR = 2.0, 95% CI = 1.0-4.0, p < 0.05), low platelet count (aOR = 5.4, 95% CI = 2.7-11.0, p < 0.001), elevated GGT (aOR = 5.0, 95% CI = 2.9-8.8, p < 0.001), and MAFLD (aOR = 3.2, 95% CI = 1.7-5.9, p < 0.001).

CONCLUSION

A high prevalence of MAFLD and advanced liver fibrosis was observed among hemodialysis patients. Nephrologists should consider a more proactive approach in diagnosing MAFLD and/or advanced liver fibrosis in hemodialysis patients.

Current and Evolving Indications for Simultaneous Liver Kidney Transplantation

This review will discuss the etiologies of kidney disease in liver transplant candidates, provide a historical background of the prior evolution of simultaneous liver-kidney (SLK) transplant indications, discuss the current indications for SLK including Organ Procurement and Transplantation Network policies and Model for End Stage Liver Disease exception points, as well as provide an overview of the safety net kidney transplant policy. Finally, the authors explore unanswered questions and future research needed in SLK transplantation.

Association between Gastroesophageal Reflux Disease and Elastographic Parameters of Liver Steatosis and Fibrosis: Controlled Attenuation Parameter and Liver Stiffness Measurements

AIM

Our aim was to investigate the association among elastographic parameters of liver steatosis and fibrosis, controlled attenuation parameter (CAP) and liver stiffness measurement (LSM), with gastroesophageal reflux disease (GERD).

METHODS

In this prospective, cross-sectional study, we have evaluated 937 patients with one or more components of the metabolic syndrome who had an esophagogastroduodenoscopy (EGD) due to GERD symptoms. In all patients, a laboratory analysis, an abdominal ultrasound, and FibroScan measurements were done. GERD was defined by EGD.

RESULTS

The mean body mass index (BMI) of the study population was 30.95 ± 5.45 kg/m². The prevalence of increased CAP was 82.6% (774/937). Patients with increased CAP were younger, were more obese, had higher prevalence of hypertension, diabetes, and dyslipidemia, and had higher values of aminotransferases. Similar results of higher prevalence in patients with elevated CAP were observed with GERD, hiatal hernia, and insufficient cardia (defined as deficient or absent closure of the gastric inlet in relation to the esophagus). Additionally, patients with elevated CAP had a higher prevalence of GERD grades B and C in comparison to those without elevated CAP. Consequently, patients who did not have elevated CAP had a higher prevalence of GERD grade A. Even though we have found an upward trend in the prevalence of GERD, hiatal hernia, and insufficient cardia, there was no significant difference between subjects with fibrosis (F) 1-2 and F3-4 stage of fibrosis or F1 and F2-4. In a binary logistic regression, a significant positive association with GERD was obtained for CAP. Furthermore, a significant positive association with hiatal hernia was obtained for BMI and CAP. Finally, a significant positive association with hiatal hernia was obtained with CAP in multivariate analysis.

CONCLUSION

To the best of our knowledge, our study is the first to reveal a positive association between CAP as a surrogate marker of liver steatosis and GERD after adjustments for other clinical variables.

Urine biomarkers in renal allograft

There is a high risk for the survival of patients with an end-stage renal disease for kidney transplantation. To avoid rejection by strict medication adherence is of utmost importance to avoid the failure of a kidney transplant. It is imperative to develop non-invasive biomarkers to assess immunity risk, and to ultimately provide guidance for therapeutic decision-making following kidney transplantation. Urine biomarkers may represent the promising non-invasive tools that will help in predicting risk or success rates of kidney transplantations. Furthermore, composite urinary biomarkers or urinary biomarker panel array might be critical in improving the sensitivity and specificity in reflecting various risks of kidney failure during transplantation. This review primarily focuses on the role of such biomarkers in predicting chronic kidney disease (CKD) progression and/or cardiovascular disease (CVD) risk in renal allograft.

Metabolic syndrome and non-alcoholic fatty liver disease after liver or kidney transplantation

Transplantation is a definitive treatment option for patients with end-stage liver disease, and for some patients with acute liver failure, hepatocellular carcinoma or end-stage renal disease. Long-term post-transplantation complications have become an important medical issue, and cardiovascular diseases (CVD) are now the leading cause of mortality in liver or kidney transplant recipients. The increased prevalence of metabolic syndrome (MS) likely plays a role in the high incidence of post-transplantation CVD. MS and its hepatic manifestation, non-alcoholic fatty liver disease (NAFLD), are prevalent among the general population and in pre- and post-transplantation settings. MS components are associated with recurrent or de novo NAFLD in transplant recipients, potentially influencing post-transplantation survival. Moreover, recent data reveal an important association between NAFLD and risk of incident of chronic kidney disease (CKD). Therefore, NAFLD identification could represent an additional clinical feature for improving the stratification of liver and kidney transplant recipients with regards to risks of CVD, CKD and renal allograft dysfunction. All MS components are potentially modifiable; therefore, it is crucial that hepatologists, nephrologists and primary care physicians become more engaged in managing post-transplantation metabolic complications. The present review discusses the recent clinical evidence regarding the importance of MS and its components after liver and kidney transplantation, as well as the link between MS and NAFLD after liver and kidney transplantation.

Short-term prospective study of prescribed physical activity in kidney transplant recipients

Regular physical exercise plays a role in improving cardiovascular and muscular fitness in many metabolic diseases. This study aims to verify any possible benefits, including the eventual influence on any associated risk factors, in a group of kidney transplant recipients after a short period of personalized training programs with mixed exercises. In January 2013, at the Sports Medicine Center of the University of Florence, Italy, we began studying a group of 20 kidney transplant recipients. After 6 months of exercise, they underwent Cardiopulmonary Test (CPET), ECG, skin fold, bioimpedance analysis and stress test for the lower and upper limbs. EF increased significantly from 63.38 ± 4 to 67.30 ± 5.9 with p < 0.05; the anaerobic threshold improved from 14.48 ± 6.3 to 20.24 ± 3.7 (p < 0.05) with good stress tolerance, estimated by CR10 scale; weight decreased significantly (70.06-65.03 kg) as did skin folds at pectoral level (p < 0.002). Upper limb muscular strength increased significantly (p < 0.005). Regular mixed exercise is a proposed program in post-transplant syndrome with the expectation of improving cardiovascular performance and enhancing exercise tolerance. Muscle strength improves with physical fitness with consequent reduction of risk factors linked to visceral fat. Proof of an eventual positive impact on other complex aspects associated with post-transplant metabolic syndrome will require a longer follow-up.

Research advances in the relationship between nonalcoholic fatty liver disease and atherosclerosis

Nonalcoholic fatty liver disease (NAFLD) is a metabolic stress-induced liver disease that is closely related not only to genetic susceptibility but also to insulin resistance and highly linked with metabolic syndrome. In recent years, the prevalence of NAFLD has increased rapidly, paralleling the epidemic of type 2 diabetes mellitus and obesity leading to cardiovascular disease. It has been demonstrated that NAFLD is highly associated with atherosclerosis. With recently gained knowledge, it appears that NAFLD may induce insulin resistance, dyslipidemia, oxidative stress, inflammation, and fluctuation of adipokines associated with atherosclerosis. In this review, we aimed to summarize recent discoveries related to both NAFLD and atherosclerosis, and to identify possible mechanisms linking them.

Usefulness of liver test and controlled attenuation parameter in detection of nonalcoholic fatty liver disease in patients with chronic renal failure and coronary heart disease

BACKGROUND

In recent years, nonalcoholic fatty liver disease (NAFLD) was recognized as an important factor in chronic kidney disease (CKD) pathogenesis. The concentrations of serum aminotransferases in both chronic dialysis and chronic renal failure (CRF) patients most commonly fall within the lower end of the range of normal values. The aim of the present study was to investigate the usefulness of four liver tests and four biological scores in detection of NAFLD in comparison with transient elastography (TE) findings in different groups of patients.

METHODS

The study was cross-sectional analysis collected data from a single tertiary care center. Of 202 patents there were 52 patients with CKD, 50 patients with end-stage renal disease (ESRD) treated with haemodialysis (HD), 50 renal transplant recipients (RTRs) and 50 patients with proven coronary heart disease (CHD). Fifty sex- and age-matched individuals without NAFLD and with normal liver and kidney function tests served as controls. With the help of TE (FibroScan®, Echosense SA, Paris, France), liver stiffness was selected as the parameter to quantify liver fibrosis and Controlled Attenuation Parameter (CAP) was used to detect and quantify liver steatosis.

RESULTS

According to the CAP findings 76.9 %CKD patients, 82 %HD patients, 74 %RTRs and 69.1 % CHD patients had CAP > 238 dB.m(-1) and thus by definition NAFLD. We have found that ALT, AST and GGT levels were positively correlated with CAP values while ALT and AST showed positive correlation with liver stiffness acquired with TE only in CHD patients. According to TE findings APRI (AUC 0.796) and FIB-4 (AUC 0.790) scores were correlated with the presence of fibrosis, while HIS score was correlated with the presence of steatosis (AUC 0.867) only in CHD patients.

CONCLUSION

Liver tests and biological scores are not useful for NAFLD detection in CRF patients. TE with CAP provides the opportunity of noninvasive screening for NAFLD as well as liver fibrosis in patients with CRF.

Transient elastography: a new noninvasive diagnostic tool for assessment of chronic allograft nephropathy

PURPOSE

Chronic allograft nephropathy (CAN) is the most common cause of kidney allograft failure. Protocol biopsies remain the "gold standard" in CAN recognition. However, renal allograft biopsies have numerous limitations. It is an invasive procedure connected with risk of complications, patient discomfort, and sampling errors. The aim of our study was to investigate the usefulness of transient elastography (TE) for the assessment of kidney allograft fibrosis in renal transplant recipients (RTRs).

METHODS

In this cross-sectional study, we involved 52 RTRs. Renal allograft stiffness was used to assess its fibrosis by using transient elastography (Fibroscan, Echosense, Paris, France). In 23 patients with a deterioration of graft function, percutaneous renal allograft biopsy was performed closely around the time of TE.

RESULTS

We have found that the renal allograft stiffness was highly negatively correlated with estimated glomerular filtration rate (eGFR) (r = -0.640; p < 0.0001). However, renal allograft stiffness showed a statistically significant difference between patients who had an eGFR > 50 ml/min per 1.73 m(2) and patients with eGFR < 50 ml/min per 1.73 m(2) (28 ± 2.7 vs. 33.9 ± 5.5 kPa; p = 0.0003). Also, there was a highly positive correlation between renal allograft stiffness and extent of interstitial fibrosis on renal biopsy (r = 0.727; p = 0.0001).

CONCLUSION

According to our results, parenchymal stiffness obtained by TE reflects interstitial fibrosis. Therefore, TE provides the opportunity for noninvasive screening of CAN.

Chronic kidney disease and nonalcoholic Fatty liver disease-is there a link?

Research in recent years has led to the recognition of the importance of nonalcoholic fatty liver disease (NAFLD) and its relationship to the metabolic syndrome (MS). This has led to a growing interest in the potential prognostic value of NAFLD for adverse cardiovascular disease (CVD) outcome. On the other hand, searching for new risk factors for chronic kidney disease (CKD) development and progression is very important. Growing evidence suggests that the MS is an important factor in the pathogenesis of CKD. The best confirmation of this pathogenic link is hypertensive and diabetic nephropathy as the main causes of CKD. Furthermore, the possible link between NAFLD and CKD has also attracted research interest and recent data suggest an association between these two conditions. These findings have fuelled concerns that NAFLD may be a new and added risk factor for the development and progression of CKD. NAFLD and CKD share some important cardiometabolic risk factors and possible common pathophysiological mechanisms, and both are linked to an increased risk of incident CVD events. Therefore, common factors underlying the pathogenesis of NAFLD and CKD may be insulin resistance, oxidative stress, activation of rennin-angiotensin system, and inappropriate secretion of inflammatory cytokines by steatotic and inflamed liver.