Alterations in glucose metabolism associated with liver cirrhosis persist in the clinically stable long-term course after liver transplantation

In silico investigation of molecular networks linking gastrointestinal diseases, malnutrition, and sarcopenia

Malnutrition (MN) is a common primary or secondary complication in gastrointestinal diseases. The patient’s nutritional status also influences muscle mass and function, which can be impaired up to the degree of sarcopenia. The molecular interactions in diseases leading to sarcopenia are complex and multifaceted, affecting muscle physiology, the intestine (nutrition), and the liver at different levels. Although extensive knowledge of individual molecular factors is available, their regulatory interplay is not yet fully understood. A comprehensive overall picture of pathological mechanisms and resulting phenotypes is lacking. In silico approaches that convert existing knowledge into computationally readable formats can help unravel mechanisms, underlying such complex molecular processes. From public literature, we manually compiled experimental evidence for molecular interactions involved in the development of sarcopenia into a knowledge base, referred to as the Sarcopenia Map. We integrated two diseases, namely liver cirrhosis (LC), and intestinal dysfunction, by considering their effects on nutrition and blood secretome. We demonstrate the performance of our model by successfully simulating the impact of changing dietary frequency, glycogen storage capacity, and disease severity on the carbohydrate and muscle systems. We present the Sarcopenia Map as a publicly available, open-source, and interactive online resource, that links gastrointestinal diseases, MN, and sarcopenia. The map provides tools that allow users to explore the information on the map and perform in silico simulations.

Hepatogenous diabetes: Knowledge, evidence, and skepticism

The diabetogenic potential of liver cirrhosis (LC) has been known for a long time, and the name "hepatogenous diabetes" (HD) was coined in 1906 to define the condition. Diabetes mellitus (DM) that develops as a consequence of LC is referred to as HD. In patients with LC, the prevalence rates of HD have been reported to vary from 21% to 57%. The pathophysiological basis of HD seems to involve insulin resistance (IR) and pancreatic β-cell dysfunction. The neurohormonal changes, endotoxemia, and chronic inflammation of LC initially create IR; however, the toxic effects eventually lead to β-cell dysfunction, which marks the transition from impaired glucose tolerance to HD. In addition, a number of factors, including sarcopenia, sarcopenic obesity, gut dysbiosis, and hyperammonemia, have recently been linked to impaired glucose metabolism in LC. DM is associated with complications and poor outcomes in patients with LC, although the individual impact of each type 2 DM and HD is unknown due to a lack of categorization of diabetes in most published research. In fact, there is much skepticism within scientific organizations over the recognition of HD as a separate disease and a consequence of LC. Currently, T2DM and HD are being treated in a similar manner although no standardized guidelines are available. The different pathophysiological basis of HD may have an impact on treatment options. This review article discusses the existence of HD as a distinct entity with high prevalence rates, a strong pathophysiological basis, clinical and therapeutic implications, as well as widespread skepticism and knowledge gaps.

Clinical implications of diabetes in chronic liver disease: Diagnosis, outcomes and management, current and future perspectives

Diabetes mellitus (DM) is common in liver cirrhosis (LC). The pathophysiological association is bidirectional. DM is a risk factor of LC and LC is a diabetogenic condition. In the recent years, research on different aspects of the association DM and LC has been intensified. Nevertheless, it has been insufficient and still exist many gaps. The aims of this review are: (1) To discuss the latest understandings of the association of DM and LC in order to identify the strategies of early diagnosis; (2) To evaluate the impact of DM on outcomes of LC patients; and (3) To select the most adequate management benefiting the two conditions. Literature searches were conducted using PubMed, Ovid and Scopus engines for DM and LC, diagnosis, outcomes and management. The authors also provided insight from their own published experience. Based on the published studies, two types of DM associated with LC have emerged: Type 2 DM (T2DM) and hepatogenous diabetes (HD). High-quality evidences have determined that T2DM or HD significantly increase complications and death pre and post-liver transplantation. HD has been poorly studied and has not been recognized as a complication of LC. The management of DM in LC patients continues to be difficult and should be based on drug pharmacokinetics and the degree of liver failure. In conclusion, the clinical impact of DM in outcomes of LC patients has been the most studied item recently. Nevertheless many gaps still exist particularly in the management. These most important gaps were highlighted in order to propose future lines for research.

The Effect of Stem Cell Transplantation Therapy for Post Viral Chronic Liver Cell Failure on Associated Type II Diabetes Mellitus: A Pilot Study

BACKGROUND

It was observed that type II diabetes mellitus associated with chronic liver failure improved after stem cell transplantation. However, there were no adequate studies regarding this issue. The aim of this study was to evaluate the effect of stem cell transplantation on associated type II diabetes mellitus and on the liver function tests.

METHODS

This pilot study included 30 patients of post-hepatitis chronic liver failure who were classified into two groups: Group I included patients with chronic liver cell failure associated with type 2 diabetes. Group II included patients without type II diabetes. Autologous CD34+ and CD133+ stem cells were percutaneously infused into the portal vein. Responders (regarding the improvement of diabetes as well as improvement of liver condition) and non-responders were determined. Patients were followed up for one, three and six months after the intervention evaluating their three-hour glucose tolerance test, C- peptide (Fasting and postprandial), Child-Pugh score and performance score one month, three months, and six months after stem cell therapy.

RESULTS

Both synthetic and excretory functions of the liver were improved in 10 patients (66.66 %) of group I and in 12 patients (80 %) of group II. Significant improvement in the Oral Glucose Tolerance Test in the responders of both the groups was well defined from the 3rd month and this was comparable to changes in liver function tests and Child-Pugh score.

CONCLUSION

Successful stem cell therapy in chronic liver cell failure patients can improve but not cure the associating type 2 diabetes by improving insulin resistance.

Cirrhosis and insulin resistance: current knowledge, pathophysiological mechanisms, complications and potential treatments

End-stage chronic liver diseases are often associated with insulin resistance (IR) and diabetes mellitus (DM). Indeed, to quantify insulin sensitivity the euglycemic clamp technique was utilized, allowing the following to be stated: in small groups of patients, an IR in almost all cirrhotic patients can be observed, compared with a control group. Additionally, it has been demonstrated that IR in cirrhosis is linked to a decreased peripheral (muscle) glucose uptake rather than an increased liver glucose production. The homoeostasis model of IR (HOMA-IR) technique, devised only later, was then exploited to assess this same phenomenon in a larger sample population. The research established that even in patients with preserved liver function, cirrhosis is associated with significant alterations in glucose homoeostasis levels. The purpose of the present paper is to present the current research around the affiliation of cirrhosis and IR, discuss potential mechanisms explaining the association between cirrhosis and IR (i.e. endocrine perturbation, liver inflammation, altered muscle mass and composition, altered gut microbiota and permeability), complications that can arise as well as treatment options, through a critical review of the literature surrounding this subject. This research will also be investigating the beneficial impact, if there is any, of identifying and curing IR in patients with cirrhosis.

ESPEN practical guideline: Clinical nutrition in liver disease

BACKGROUND

The Practical guideline is based on the current scientific ESPEN guideline on Clinical Nutrition in Liver Disease.

METHODS

It has been shortened and transformed into flow charts for easier use in clinical practice. The guideline is dedicated to all professionals including physicians, dieticians, nutritionists and nurses working with patients with chronic liver disease.

RESULTS

A total of 103 statements and recommendations are presented with short commentaries for the nutritional and metabolic management of patients with (i) acute liver failure, (ii) alcoholic steatohepatitis, (iii) non-alcoholic fatty liver disease, (iv) liver cirrhosis, and (v) liver surgery/transplantation. The disease-related recommendations are preceded by general recommendations on the diagnostics of nutritional status in liver patients and on liver complications associated with medical nutrition.

CONCLUSION

This practical guideline gives guidance to health care providers involved in the management of liver disease to offer optimal nutritional care.

Clinical implications, diagnosis, and management of diabetes in patients with chronic liver diseases

Diabetes mellitus (DM) negatively affects the development and progression of chronic liver diseases (CLD) of various etiologies. Concurrent DM and CLD are also associated with worse clinical outcomes with respect to mortality, the occurrence of hepatic decompensation, and the development of hepatocellular carcinoma (HCC). Unfortunately, early diagnosis and optimal treatment of DM can be challenging, due to the lack of established clinical guidelines as well as the medical complexity of this patient population. We conducted an exploratory review of relevant literature to provide an up-to-date review for internists and hepatologists caring for this patient population. We reviewed the epidemiological and pathophysiological associations between DM and CLD, the impact of insulin resistance on the progression and manifestations of CLD, the pathogenesis of hepatogenic diabetes, as well as the practical challenges in diagnosis and monitoring of DM in this patient population. We also reviewed the latest clinical evidence on various pharmacological antihyperglycemic therapies with an emphasis on liver disease-related clinical outcomes. Finally, we proposed an algorithm for managing DM in patients with CLD and discussed the clinical and research questions that remain to be addressed.

Postoperative hyperglycemia may negatively impact cytomegalovirus infection in seropositive liver transplant recipients: a retrospective cohort study

The aim of the study was to evaluate the association between postoperative hyperglycemia and CMV infection. We analyzed 741 CMV seropositive recipients, of livers from seropositive living donors, who underwent preemptive CMV treatment without CMV prophylaxis. The primary outcome was early CMV infection within 1 month after surgery. Hyperglycemia was defined when mean postoperative blood glucose concentration was >180 mg/dl based on previous research and guidelines. Survival analysis was performed using the Fine and Gray model by accounting for the competing risk of CMV infection-unrelated death. Of the 741 recipients (hyperglycemic group, n = 287; nonhyperglycemic group, n = 454), 372 (50.2%) recipients developed cytomegalovirus (CMV) infection within 1 month after surgery. CMV infection risk was significantly higher in hyperglycemic group than in nonhyperglycemic group in univariable analysis [hazard ratio (HR) 1.34, 95% confidence interval (CI), 1.08-1.66; P = 0.007] and in multivariable analysis (HR 1.25, 95% CI 1.0-1.54; P = 0.038). CMV infection risk was also significantly associated with recipient age, graft ischemia time, model for end-stage liver disease score, and preoperative neutrophil-to-lymphocyte ratio (P < 0.05). In conclusion, preventing postoperative hyperglycemia appears to be an important factor decreasing the risk of CMV infection in seropositive liver transplant recipients undergoing preemptive CMV treatment.

ESPEN guideline on clinical nutrition in liver disease

This update of evidence-based guidelines (GL) aims to translate current evidence and expert opinion into recommendations for multidisciplinary teams responsible for the optimal nutritional and metabolic management of adult patients with liver disease. The GL was commissioned and financially supported by ESPEN. Members of the guideline group were selected by ESPEN. We searched for meta-analyses, systematic reviews and single clinical trials based on clinical questions according to the PICO format. The evidence was evaluated and used to develop clinical recommendations implementing the SIGN method. A total of 85 recommendations were made for the nutritional and metabolic management of patients with acute liver failure, severe alcoholic steatohepatitis, non-alcoholic fatty liver disease, liver cirrhosis, liver surgery and transplantation as well as nutrition associated liver injury distinct from fatty liver disease. The recommendations are preceded by statements covering current knowledge of the underlying pathophysiology and pathobiochemistry as well as pertinent methods for the assessment of nutritional status and body composition.

Hepatogenous Diabetes: An Underestimated Problem of Liver Cirrhosis

The prevalence of diabetes mellitus in cirrhotic patients is much higher than that in the general population. Two types of diabetes are usually seen in patients with cirrhosis: type 2 diabetes mellitus and hepatogenous diabetes (HD). The HD is an acquired condition which is believed to be caused by impaired insulin clearance and pancreatic β-cell dysfunction in cirrhotic patients. Increased levels of advanced glycation end products and hypoxia-inducible factors have been implicated in the pathogenesis of HD. Patients with HD typically present with normal fasting glucose, but abnormal response to an oral glucose tolerance test, which is required for the diagnosis. Because the level of glycated hemoglobin is often falsely low in patients with cirrhosis, it does not help in the early diagnosis of HD. HD is associated with an increased rate of complications of cirrhosis, decreased 5-year survival rate, and increased risk of hepatocellular carcinoma. The major complications of cirrhosis associated with HD include hepatic encephalopathy (HE), spontaneous bacterial peritonitis, sepsis, variceal hemorrhage, and renal dysfunction. Treatment of HD may be difficult as many antihyperglycemic therapies are associated with increased risk of complications in cirrhosis, particularly hypoglycemia. Biguanides, alpha-glucosidase inhibitors, and new medications such as dipeptidyl peptidase-4 inhibitors and sodium-glucose co-transporter 2 inhibitors appear to be safe in patients with cirrhosis. Though insulin therapy is currently advocated, requirement of insulin is variable and is difficult to predict. The liver transplantation usually results in reversal of HD. This review article provides an overview of magnitude, patients' characteristics, clinical implications, pathophysiological mechanisms, diagnosis, and management of HD.

Hepatogenous diabetes: Is it time to separate it from type 2 diabetes?

By definition, hepatogenous diabetes is directly caused by loss of liver function, implying that it develops after cirrhosis onset. Therefore, it should be distinguished from type 2 diabetes developing before cirrhosis onset, in which specific causes of liver disease play a major role, in addition to traditional risk factors. Currently, although hepatogenous diabetes shows distinct pathophysiological and clinical features, it is not considered as an autonomous entity. Recent evidence suggests that the failing liver exerts an independent "toxic" effect on pancreatic islets resulting in β-cell dysfunction. Moreover, patients with hepatogenous diabetes usually present with normal fasting glucose and haemoglobin A_1c levels and abnormal response to an oral glucose tolerance test, which is therefore required for diagnosis. This article discusses the need to separate hepatogenous diabetes from type 2 diabetes occurring in subjects with chronic liver disease and to identify individuals suffering from this condition for prognostic and therapeutic purposes.

Diagnosis and Clinical Implications of Diabetes in Liver Cirrhosis: A Focus on the Oral Glucose Tolerance Test

The liver and skeletal muscles are responsible for maintaining glucose metabolism. As chronic liver disease progresses to cirrhosis, the loss of liver function is exacerbated and leads to the deterioration of skeletal muscle. Consequently, impaired glucose tolerance (IGT) and insulin resistance are often observed in patients with liver cirrhosis. Early stage cirrhosis with hepatogenous diabetes is characterized by marked postprandial hyperglycemia and hyperinsulinemia. Generally, it is possible to underestimate IGT when using either the conventional fasting plasma glucose (FPG) criterion or hemoglobin A_1c (HbA_1c) levels despite their status as the gold standard for diagnosing diabetes. The number of cirrhotic patients with diabetes tends to be underestimated because many of these patients show lower FPG levels or HbA_1c, which masks their IGT. In such cases, the oral glucose tolerance test is recommended to evaluate patients with suspected postprandial hyperglycemia who present with a normal FPG. Moreover, in addition to the Child-Pugh score, the early detection of diabetes may be a useful prognostic marker for patients with liver cirrhosis.

Molecular changes in hepatic metabolism and transport in cirrhosis and their functional importance

Liver cirrhosis is the common endpoint of many hepatic diseases and represents a relevant risk for liver failure and hepatocellular carcinoma. The progress of liver fibrosis and cirrhosis is accompanied by deteriorating liver function. This review summarizes the regulatory and functional changes in phase I and phase II metabolic enzymes as well as transport proteins and provides an overview regarding lipid and glucose metabolism in cirrhotic patients. Interestingly, phase I enzymes are generally downregulated transcriptionally, while phase II enzymes are mostly preserved transcriptionally but are reduced in their function. Transport proteins are regulated in a specific way that resembles the molecular changes observed in obstructive cholestasis. Lipid and glucose metabolism are characterized by insulin resistance and catabolism, leading to the disturbance of energy expenditure and wasting. Possible non-invasive tests, especially breath tests, for components of liver metabolism are discussed. The heterogeneity and complexity of changes in hepatic metabolism complicate the assessment of liver function in individual patients. Additionally, studies in humans are rare, and species differences preclude the transferability of data from rodents to humans. In clinical practice, some established global scores or criteria form the basis for the functional evaluation of patients with liver cirrhosis, but difficult treatment decisions such as selection for transplantation or resection require further research regarding the application of existing non-invasive tests and the development of more specific tests.

Alterations in carbohydrate metabolism in cirrhotic patients before and after liver transplant

AIM

The main objective of this study is to demonstrate whether carbohydrate metabolism alterations identified in patients with advanced cirrhosis show any improvement after liver transplant.

METHODS

The study included 86 patients who underwent liver transplant between March 2010 and February 2011. An oral glucose tolerance test was performed before the liver transplant, and 6 and 12 months after. Beta cell function and insulin resistance were also calculated, applying formulae that use basal plasma glycaemia and insulin, and plasma glycaemia and insulin during an oral glucose tolerance test. Risk factors for pre- and post-transplant diabetes were also studied. The diagnosis of diabetes was based on an OGTT.

RESULTS

The proportion of patients with diabetes before transplant, and at month 6 and 12 after transplant were 70.9%, 48.8% and 39.2%, respectively. Compared to baseline, at month 6 the odds ratio of having diabetes was 0.39 (IC 95% [0.21, 0.73]) and at month 12 it was 0.26 (IC 95% [0.14, 0.50]). The composite insulin sensitivity index values at 6 and 12 months were 1.72 units higher (IC 95% [0.84, 2.58]) and 1.58 units higher (IC 95% [0.68, 2.44)] than baseline. A statistically significant association was found between high MELD values and high body mass index, and risk of pre-transplant diabetes (p=0.001 and p=0.033, respectively). Cirrhosis aetiology did not influence the risk of diabetes.

CONCLUSIONS

In this study, we were able to ascertain that alterations in carbohydrate metabolism typical of advanced cirrhosis improve after liver transplant. This improvement is mainly due to an improvement in insulin resistance.

Clinical Usefulness of ¹⁸F-FDG PET/CT for the Detection of Infections of Unknown Origin in Patients Undergoing Maintenance Hemodialysis

Patients with end-stage renal disease undergoing maintenance hemodialysis (MHD) are highly prone to infections. The potential clinical usefulness of (18)F-FDG PET/CT for the detection of infections of unknown origin in this patient population remains unclear. This study was designed to investigate this issue.

METHODS

Between October 2011 and July 2014, a total of 104 adult MHD patients with sepsis underwent (18)F-FDG PET/CT for the detection of unknown infection foci. Follow-up was continued until October 2014. Positive (18)F-FDG PET/CT findings and mortality served as the main outcome measures.

RESULTS

Of the 104 study patients, 73 (70.2%) had positive (18)F-FDG PET/CT findings, and a total of 95 major infection foci were identified. Eighteen patients (24.6%) had at least 2 infection foci on (18)F-FDG PET/CT scans. Seven (53.8%) of the 13 patients with primary vascular access-related infections had concurrent metastatic foci. Twenty-eight patients (26.9%) had their treatments modified by (18)F-FDG PET/CT results. Multivariate logistic regression analysis demonstrated that low hemoglobin and high C-reactive protein levels at diagnosis were the independent predictors of positive (18)F-FDG PET/CT results. Twenty-seven patients (26.0%) died during their hospital stay, and 24 of them had positive (18)F-FDG PET/CT findings (P = 0.014). Positive (18)F-FDG PET/CT results were an independent predictor of mortality (hazard ratio, 3.896; 95% confidence interval, 1.039-14.613; P = 0.044).

CONCLUSION

Our results suggest that (18)F-FDG PET/CT may be clinically useful for detecting occult infection foci in end-stage renal disease patients undergoing MHD. In this population, positive (18)F-FDG PET/CT findings may lead to a significant change in clinical management and independently predict mortality.

Hepatitis C virus and metabolic disorder interactions towards liver damage and atherosclerosis

Hepatitis C virus (HCV) is one of the main causes of liver disease worldwide, and alterations of glucose metabolism have reached pandemic proportions in western countries. However, the frequent coexistence between these two conditions is more than simply coincidental, since HCV can induce insulin resistance through several mechanisms. Indeed, the virus interferes with insulin signaling both directly and indirectly, inducing the production of pro-inflammatory cytokines. Furthermore, the entire viral life cycle has strict interconnections with lipid metabolism, and HCV is responsible for a “viral” steatosis which is frequently superimposed to a “metabolic” one. Several evidences suggest that HCV-induced metabolic disorders contribute both to the evolution of liver fibrosis and, likely, to the progression of the other disorders which are typically associated with altered metabolism, in particular atherosclerosis. In the present review, we will examine in depth the links between HCV infection and insulin resistance, liver steatosis and diabetes, and analyze the impact of these interactions on the progression of liver fibrosis and atherosclerosis. Special attention will be focused on the highly debated topic of the relationship between HCV infection and cardiovascular disease. The available clinical literature on this item will be broadly reviewed and all the mechanisms possibly implied will be discussed.

Potential usefulness of FDG PET/CT in patients with sepsis of unknown origin

Purpose

The role of FDG PET in the evaluation of patients with sepsis of unknown origin remains unclear. We sought to assess the value of FDG PET/CT in patients with sepsis of unknown cause and to define its priority in this group of subjects.

Methods

A total of 53 patients with sepsis of unknown origin underwent FDG PET/CT within two weeks of diagnosis. All of the patients were followed up for at least 3 months after discharge to determine the clinical outcomes. The impact of FDG PET/CT was assessed according to the number of cases who had their treatment modified on the basis of the imaging results. Logistic regression analysis was used to identify the independent predictors of positive FDG PET/CT findings.

Results

Of the 53 study patients, 35 (66%) had positive FDG PET/CT findings, and 13 (25%) had their treatment modified on the basis of the imaging results. Logistic regression analysis identified normal serum aspartate aminotransferase (odds ratio [OR]  = 6.134; 95% confidence interval [CI]  = 1.443–26.076, P = 0.014) and increased serum alkaline phosphatase levels (OR = 5.813; 95% CI = 1.386–24.376, P = 0.016) at diagnosis as independent predictors of positive FDG PET/CT findings. A scoring system using these two covariates was developed, which defined three distinct priority groups for FDG PET/CT imaging.

Conclusion

Our findings suggest that FDG PET/CT may be clinically useful for the detection of occult foci of infection in patients with sepsis of unknown origin.

Prospective assessment of renal histopathological lesions in patients with end-stage liver disease: effects on long-term renal function after liver transplantation

BACKGROUND & AIMS

The incidence of organic renal lesions in patients with end-stage liver disease is unknown. The goal of this study was to make a prospective evaluation of renal histological lesions in a group of unselected patients awaiting liver transplantation.

METHODS

Sixty cirrhotic patients underwent a renal biopsy via the transjugular route. The potential effect of renal lesions on renal function was evaluated five years after transplantation.

RESULTS

The yield of biopsies enabling satisfactory analysis was 77%, and no major complications occurred. Proteinuria>0.5 g/day was observed in only 8.7% of these patients, microscopic haematuria in 4.3%, creatinine levels>133 mmol/L (1.5mg/dl) in 10.9%, and Modification of the Diet in Renal Disease (MDRD) clearance<60 ml/min in 13.0%. Twenty-five patients (55.3%) had a morphological diagnosis of renal disease, 15 displayed IgA nephropathy and immunofluorescence testing showed that 12 had specific diabetic linear staining for IgG and albumin, of whom seven had associated histological lesions of diabetic nephropathy. Five years after liver transplantation, renal function had significantly deteriorated more in patients with initial diabetic lesions than in those with normal histology or IgA nephropathy alone.

CONCLUSIONS

In patients with end-stage liver disease, IgA nephropathy and diabetic lesions were frequently found despite the absence of renal impairment and/or urinalysis anomalies. Our results strongly suggest that severe renal failure develops preferentially in liver transplant recipients with diabetes or carbohydrate intolerance, and that pre-existing arterial lesions may favour the nephrotoxicity of calcineurin inhibitors. Diabetes prior to transplantation needs to be strictly managed and requires a renal sparing immunosuppressive regimen after transplantation.

Insulin resistance in patients with cirrhosis and portal hypertension

Insulin resistance (IR) is involved in the pathogenesis of endothelial dysfunction and is also present in patients with cirrhosis. Intrahepatic endothelial dysfunction plays a major role, increasing hepatic vascular resistance and promoting portal hypertension (PH). In addition, β-adrenergic agonists and insulin share several intracellular signaling pathways. Thus IR may influence the response to β-blockers. This study aimed at evaluating the relationship between IR and hepatic hemodynamics in patients with cirrhosis and with the portal pressure response to acute β-blockade. Forty-nine patients with cirrhosis and PH were included. Hepatic and systemic hemodynamics were measured, and IR was estimated by using the updated homeostasis model assessment (HOMA)-2 index. Patients with HOMA-2 > 2.4 were considered IR. In patients with hepatic venous pressure gradient (HVPG) ≥ 10 mmHg) [clinically significant PH (CSPH)], hemodynamic measurements were performed again 20 min after intravenous propranolol. Mean HOMA-2 index was 3 ± 1.4. Fifty-seven percent of patients had IR. A weak correlation between HOMA-2 index and HVPG was observed. Eighty-six percent of patients had CSPH. HOMA-2 index was an independent predictor of CSPH. However, in patients with CSPH, the correlation between HOMA-2 index and HVPG was lost. HVPG, but not IR, predicted the presence of esophageal varices. Response to propranolol was not different between patients with or without IR. In nondiabetic patients with cirrhosis, HOMA-2 index is directly associated with the presence of CSPH and indirectly with varices, but does not allow either grading HVPG or predicting its response to propranolol.

[New-onset diabetes mellitus and liver transplantation, with special consideration of recurrent hepatitis C]

New-onset diabetes is a common complication after liver transplantation.

AIM

We aimed to analyze the incidence and rate of known risk factors and the impact of new-onset diabetes mellitus on postoperative outcome.

METHODS

We retrospectively evaluated the files of 310 patients who underwent liver transplantation between 1995 and 2009. Definition of new-onset diabetes included: repeated fasting serum glucose >6.8 mmol/l and/or sustained antidiabetic therapy that was present 3 months after transplantation.

RESULTS

New-onset diabetes occurred in 63 patients (20%). Differences between the new-onset and the control group were the donor body mass index (24+/-3 vs. 22.4+/-3.6 kg/m 2 , p = 0.003), donor male gender (58% vs. 33%, p = 0.002), and recipient age (47.6+/-7.2 vs. 38.3+/-14.6 year, p<0.001), body mass index (26.7+/-3.8 vs. 23.3+/-5.6 kg/m 2 , p<0.001), male gender (60% vs. 44%, p = 0.031). The 66% of patients with new-onset diabetes were transplanted with cirrhosis caused by hepatitis C virus infection, while in the control group the rate was 23% (p<0.001). Cumulative patient survival rates at 1, 3, 5 and 8 year were 95%, 90.6%, 88% and 88% in the control group, and 87%, 79%, 79% and 64% in the de novo group, respectively (p = 0.011). Cumulative graft survival rates at 1, 3, 5 and 8 year in the control group were 92%, 87%, 86% and 79%, in the de novo diabetes group the rates were 87%, 79%, 79%, 65%, respectively (p = NS). In case of early recurrence (in 6 months), majority of patients developed new-onset diabetes (74% vs. control 26%, p = 0.03). More patients had more than 10 times higher increase of the postoperative virus titer correlate to the preoperative titer in the de novo diabetes group (53% vs. 20%, p = 0.028). Mean fibrosis score was higher in new-onset group one year after the beginning of antiviral therapy (2.05+/-1.53 vs. 1.00+/-1.08, p = 0.039).

CONCLUSIONS

Risk factors for new-onset diabetes after transplantation are older age, obesity, male gender and cirrhosis due to hepatitis C infection. The early recurrence, viremia and more severe fibrosis after antiviral therapy have an impact on the occurrence of new-onset diabetes in hepatitis C positive patients.

Posttransplant metabolic syndrome: an epidemic waiting to happen

With increasing survival after orthotopic liver transplantation (OLT), metabolic syndrome and its individual components, including diabetes mellitus, hypertension, dyslipidemia, and obesity, are increasingly being identified and contributing to cardiovascular complications and late morbidity and mortality. The prevalence of posttransplant metabolic syndrome (PTMS) and its individual components has been found to be higher post-OLT versus a comparable population without OLT. The development of nonalcoholic fatty liver disease (NAFLD) after liver transplantation for non-NAFLD cirrhosis is also being increasingly recognized. A number of predictors have been identified as potential risk factors related to these complications. The pretransplant risk factors include immunosuppression, a higher age at transplant, male gender, a history of smoking, the pretransplant body mass index, pre-OLT diabetes, the etiology of the underlying liver disease that resulted in OLT (hepatitis C, cryptogenic cirrhosis, or alcohol), an increased donor body mass index, and marital status. Although there is an increased risk of cardiovascular events, rejection, and infection among patients with PTMS, the overall impact on long-term survival and mortality remains inconclusive. Strategies to reduce the development of metabolic syndrome after transplantation should include lifestyle modifications involving alterations in diet and increased physical activity. Additional measures that may be potentially beneficial include the use of lipid-lowering agents, the optimal control of blood glucose, and the use of tacrolimus instead of cyclosporine.

Severity of liver disease predicts the development of glucose abnormalities in patients with chronic hepatitis B or C following achievement of sustained virological response to antiviral therapy

A higher prevalence of glucose abnormalities has been reported in patients with hepatitis C virus (HCV) infection compared to patients with hepatitis B virus (HBV) infection. However, previous studies considered some confounding factors and ignored others, which might influence the comparative risk assessment between HBV and HCV infections. Fasting plasma glucose concentration, severity of liver disease and viral load were determined in 220 patients with HCV genotype 4 infection, and 200 patients with HBV infection. Patients completing antiviral therapy were followed-up, and the fasting plasma glucose levels were determined in patients with and without sustained virological response. The prevalence of glucose abnormalities in HCV infection (41%) was significantly higher than that in HBV infection (16%). However, when controlling the severity of liver disease and other risk factors, the prevalence of glucose abnormalities in patients with HCV infection was comparable to that in patients with HBV infection. After attaining of sustained virological response, a decrease of the median fasting plasma glucose value was observed only in chronic hepatitis C. In the group of patients with normal fasting plasma glucose levels, an association of nonsustained virological response with the development of impaired fasting glucose was only observed in chronic hepatitis C. The severity of liver disease was a common predictor of impaired fasting glucose in hepatitis B and C infections. These results indicate that high prevalence of glucose abnormalities can be associated with HBV- and HCV-related liver disease, and that clearance of HCV, but not HBV, may improve glucose metabolism.

Plasma levels of PBEF/Nampt/visfatin are decreased in patients with liver cirrhosis

Liver cirrhosis is a catabolic disease associated with a high incidence of insulin resistance and diabetes mellitus. Pre-B cell colony-enhancing factor/ nicotinamide phosphoribosyltransferase/visfatin has been characterized as a novel adipokine with a potential role in glucose metabolism and nicotinamide dinucleotide (NAD) generation. We studied plasma levels and metabolic relevance of visfatin in 19 patients with cirrhosis and 19 body mass index-, age-, and sex-matched controls. In addition, hepatic mRNA expression was assessed by qPCR in livers of seven patients with cirrhosis and four controls. Circulating visfatin was 78% lower in cirrhotics (P < 0.001) and decreased with worsening of the clinical stage of liver disease. Hepatic visfatin secretion decreased with clinical stage (P < 0.05) and reduced liver function (P = 0.01). Consistent with these data, hepatic visfatin mRNA expression was significantly lower in cirrhotic livers (P < 0.05). Circulating visfatin in cirrhosis was correlated with body cell mass (r = 0.72, P < 0.01) as well as with body fat mass (r = 0.53, P < 0.05) but not with plasma glucose, insulin, the degree of insulin resistance, or whole body glucose oxidation rates. Higher visfatin levels were associated with higher hepatic glucose production (r = 0.53, P < 0.05) and also with a higher arterial ketone body ratio (KBR) (r = 0.48, P < 0.05), an indicator of increased hepatic NAD generation. In conclusion, circulating visfatin levels are significantly decreased in liver cirrhosis, presumably attributable to decreased hepatic expression and production. Plasma visfatin in cirrhosis is not associated with insulin resistance but correlates with hepatic glucose production and the arterial KBR, indicating a potential link between the NAD-generating properties of visfatin and metabolism.

Decreased hepatic RBP4 secretion is correlated with reduced hepatic glucose production but is not associated with insulin resistance in patients with liver cirrhosis

OBJECTIVE

Patients with liver cirrhosis have a high incidence of insulin resistance and diabetes. This study was designed to determine circulating levels and hepatic production of retinol-binding protein 4 (RBP4) in relation to parameters of hepatic and systemic metabolism in patients with liver cirrhosis.

DESIGN AND METHOD

Circulating RBP4 levels were measured in 19 patients with liver cirrhosis at different clinical stages of the disease and in 20 age-, sex- and body mass index (BMI)-matched controls. Hepatic production rates of RBP4 and glucose were assessed by measuring the arterial hepatic venous concentration difference together with hepatic blood flow. Insulin resistance was determined by the Quantitative Insulin Sensitivity Check Index (QUICKI) and the homeostasis model assessment of insulin resistance (HOMA-IR), energy expenditure by indirect calorimetry and body composition by bioelectrical impedance analysis (BIA).

RESULTS

Compared with controls, RBP4 levels in cirrhosis were decreased (8.1 +/- 1.8 vs. 22.6 +/- 2.4 mg/l, P < 0.001) due to decreased hepatic production (P < 0.05). RBP4 correlated with hepatic protein synthesis capacity (P < 0.01), but not with insulin resistance, energy expenditure, BMI or body fat mass. Plasma RBP4 correlated with hepatic glucose production (P < 0.05).

CONCLUSIONS

These data demonstrate that RBP4 in cirrhosis (i) is decreased due to reduced hepatic production, (ii) is not associated with insulin resistance, and (iii) might have a beneficial role by decreasing hepatic glucose production and could thus also be regarded as a hepatokine.

Animal PET for thioacetamide-induced rat cholangiocarcinoma: a novel and reliable platform

PURPOSE

Cholangiocarcinoma (CCA) is a lethal disease afflicting many thousands of patients worldwide. We have previously developed an oral thioacetamide (TAA)-induced model of rat CCA that recapitulates the histologic progression of human CCA. Our objective was to evaluate the feasibility of animal PET in detecting CCA in the setting of the TAA rat model.

PROCEDURES

Male Sprague-Dawley rats (n = 30) were used in this study. Drinking water with TAA 300 mg/l was administered orally in 26 rats, and animal PET was performed at 20 weeks after initiation of TAA. A total of four rats served as controls. Animal PET images were acquired sequentially using both C-11 acetate and 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) to determine the optimal tracer. Dynamic animal PET images were collected to assess the optimal scan time based on the highest tumor-to-liver (T/L) ratio using time-activity curves. Animal PET findings were compared lesion by lesion with the results of autoradiography and the histological data.

RESULTS

FDG animal PET images had a higher T/L ratio compared to images obtained with C-11 acetate as a marker. The optimal scan time for FDG animal PET was determined as 90 min postinjection of the tracer. This was when the T/L ratio reached its peak. Necropsy and histology confirmed the presence of TAA-induced CCA in 22 rats (84.6 %). Static animal PET images showed intense FDG uptake in 17 of the 22 tumor-bearing animals (77.3%). The average T/L ratio was 1.60 +/- 0.09. The sensitivity and specificity of animal PET in the detection of CCA were 77% (17/22) and 100% (4/4), respectively.

CONCLUSIONS

We conclude that animal PET in the setting of the TAA rat model seems to be feasible for the detection of CCA. Future translational studies are needed to confirm and expand our findings.

Role of obesity, insulin resistance, and steatosis in hepatitis C virus infection

Hepatitis C, nonalcoholic fatty liver characterized by hepatic steatosis, and obesity inflict significant health and economic burdens on the Western world. Insulin resistance is the key player in these disease processes. Complex interplay between these conditions results in the ultimate phenotype of liver disease. This article focuses on the current understanding of host and viral interactions as well as on consequent clinical implications.

Elevated resistin levels in cirrhosis are associated with the proinflammatory state and altered hepatic glucose metabolism but not with insulin resistance

The adipokine resistin has been implicated in obesity and insulin resistance. Liver cirrhosis is associated with decreased body fat mass and insulin resistance. We determined plasma resistin levels in 57 patients with cirrhosis, 13 after liver transplantation, and 30 controls and correlated these with hemodynamic as well as hepatic and systemic metabolic parameters. Patients with cirrhosis had, dependent on the clinical stage, an overall 86% increase in resistin levels (P < 0.001) with hepatic venous resistin being higher than arterial levels (P < 0.001). Circulating resistin was significantly correlated with plasma TNF-alpha levels (r = 0.62, P < 0.001). No correlation was observed between resistin and hepatic hemodynamics, body fat mass, systemic energy metabolism, and the degree of insulin resistance. However, plasma resistin in cirrhosis was negatively associated with hepatic glucose production (r = -0.47, P < 0.01) and positively with circulating free fatty acids (FFA; r = 0.40, P < 0.01) and ketone bodies (r = 0.48, P < 0.001) as well as hepatic ketone body production (r = 0.40, P < 0.01). After liver transplantation, plasma resistin levels remained unchanged, whereas insulin resistance was significantly improved (P < 0.01). These data provide novel insights into the role of resistin in the pathophysiological background of a catabolic disease in humans and also indicate that resistin inhibition may not represent a suitable therapeutic strategy for the treatment of insulin resistance and diabetes in patients with liver cirrhosis.

Prevalence and risk factors for diabetes mellitus in moderate term survivors of liver transplantation

The prevalence and risk factors for diabetes mellitus after liver transplantation are not well understood. Thus, we sought to identify independent risk factors for the development of diabetes after liver transplantation using currently accepted medical criteria. We studied the prevalence and risk factors in 253 adult recipients transplanted at UCLA between January 1998 and December 2002. Analysis of the retrospective data was performed using demographic, immunosuppression and liver disease variables. Factors found to be significant on a univariate analysis were further studied in a multivariate analysis. There were 158 men and 95 women in our study. The mean age was 51.4 +/- 11.0 years. The mean [+/- standard deviation (SD) pretransplant body mass index was 26.7 (+/-5.1). Most patients were transplanted for hepatitis C (HCV). The prevalence of diabetes after transplantation was 17.8%. In a multivariate analysis only gender [odds ratio (OR) = 0.37; p = 0.02] was independently predictive of the development of diabetes. This study in a large liver transplant recipient population identifies male gender as an independent risk factor for the development of diabetes. Follow-up studies are needed to assess the impact of diabetes, and its intervention on post-transplant morbidity and mortality.

Diabetes in chronic liver disease: from old concepts to new evidence

The liver is one of the principal organs involved in glucose metabolism together with skeletal muscle and adipose tissue. A link between diabetes and chronic liver disease (CLD) was first observed in the early half of the last century, but to date several questions remain unsolved. Altered glucose tolerance has been well described in alcoholic CLD, non-alcoholic fatty liver disease, chronic hepatitis C and portal hypertension. Moreover, insulin resistance is assuming an ever-growing importance in CLD; chronic hepatitis C has recently been proposed as a metabolic disease and insulin sensitivity as a predictive factor for liver fibrosis.CLD is also complicated by acquired growth hormone (GH) resistance, characterized by low concentrations of insulin-like growth factor-1 (IGF-1) with respect to normal or elevated GH levels. GH resistance in CLD is determined by several factors, including malnutrition, impaired liver function and reduced expression of hepatic GH receptors. We recently described the possible role of tumour necrosis factor-alpha (TNF-alpha) in blunting the hepatic response to GH in patients with chronic hepatitis C. The role of GH in impaired glucose metabolism is well known, and recent evidence suggests a receptor and/or post-receptor modulation of insulin signalling. Moreover, as in other chronic inflammatory conditions, pro-inflammatory cytokines may directly modulate the signal cascade that follows insulin binding to its receptor in the course of CLD. In this review, the proposed links between impaired glucose tolerance and CLD are analysed, special emphasis being focussed on the most recent findings concerning the interplay of chronic inflammation, GH resistance and insulin resistance.

Major influence of liver function itself but not of immunosuppression determines glucose tolerance after living-donor liver transplantation

Controversial data exists concerning the impact of immunosuppressive therapy on the development of post-transplantation diabetes mellitus (PTDM). Therefore, we investigated glucose metabolism in healthy donors and in recipients of living-donor liver transplants (LD-LTX, n=18) without pre-existing diabetes mellitus before, on day 10, month 6, and month 12 after intervention. The computer-assisted analysis of glucose, insulin, and C-peptide profiles obtained from frequently sampled intravenous glucose tolerance tests allows to achieve an integrated view of factors controlling glucose tolerance, i.e., insulin sensitivity (SI), first and second phase insulin secretion (phi1 and phi2). SI of donors declined by day 10 after operation (SI 2.65 +/- 0.41 vs. 4.90 +/- 0.50 10(-4) minute(-1) microU ml(-1), P < 0.01) but returned to values as before after 6 months. Phi1 did not change. Phi(2), however, significantly increased by day 10 (8.57 +/- 0.82 10(9) minute(-1) to 13.77 +/- 1.53 10(9) minute(-1), P < 0.01) but was in the same range as before after 6 months. In parallel to donors SI of recipients progressively increased after LD-LTX. Phi1 did not alter in recipients. Phi2 continuously decreased and was not different from donors by month 12. The extent of liver injury assessed by liver enzyme concentrations and liver function represented by cholinesterase activity, albumin, and INR were closely related with changes of SI in donors and recipients during the first year after intervention. In conclusion, the extent of liver damage plays a predominant role in regulating glucose tolerance. No impact of immunosuppressive therapy on SI, phi1 and phi2 was detected.

Changes of glucose metabolism in patients with liver cirrhosis: an analysis of 46 cases

AIM: To investigate the changes of glucose metabolism and the possible mechanism.

METHODS: The levels of plasma glucose, insulin and C-peptide were measured in 46 patients with liver cirrhosis and 25 healthy people before (fasting) and 2 h after the oral glucose tolerance test (OGTT). The insulin sensitivity index (ISI) was calculated. All the results were analyzed comparatively.

RESULTS: In patients with liver cirrhosis, the levels of fasting plasma glucose and C-peptide were 5.58±2.14 mmol/L and 593±156 pmol/L, respectively (P >0.05); 2 h after OGTT, the levels of plasma glucose and C-peptide were 11.97±4.20 mmol/L and 3411±964 pmol/L, respectively, which were significantly higher than those in the healthy controls (P <0.05). In the liver cirrhosis patients, the levels of plasma insulin before (fasting) and 2 h after the OGTT were 12.23±5.4 mU/L and 105.16±40.70 mU/L, respectively, which were significantly higher than those in the healthy controls (P <0.05). The value of ISI in liver cirrhosis patients was significantly lower than that in the healthy controls (1.47±0.54 vs 2.73±0.62, P <0.05).

CONCLUSION: Abnormal glucose metabolism exists in patients with liver cirrhosis, and its mechanism may be related to the insulin resistance.

The effect of oral contrast on large bowel activity in FDG-PET/CT

PURPOSE

The purpose of this study was to determine the effect of oral contrast on FDG uptake in the colon and to determine the normal distribution of FDG in the colon.

METHODS

Sixty patients (30 patients in no contrast group and 30 patients in the received contrast group) underwent FDG-PET/ CT scans. The pattern of FDG uptake was classified into 5 patterns (diffuse, segmental, single-nodular, multi-nodular, and other) in 5 segments (ascending, transverse, descending, and rectosigmoid colon). SUVs of the no oral contrast group were examined. The ratios of FDG uptake patterns were compared in the received contrast group and no contrast group to evaluate the effect of oral contast. The effect of attenuation correction on the uptake pattern was evaluated by comparison of the attenuation-corrected and non-attenuation-corrected PET images.

RESULTS

In the no contrast group, there was no significant uptake in 72 segments (59%) and a diffuse pattern was seen in 29 segments (24%), most frequently in the ascending colon and descending colon. A segmental pattern was seen in 15 segments (13%), most frequently in the rectosigmoid colon. A single-nodular pattern was seen in 3 segments (3%) and multi-nodular pattern in 1 segment (1%). A nodular pattern was seen only in the ascending colon. SUVmax of the ascending colon and that of the rectosigmoid colon were significantly higher than those of the transverse and descending colon. The frequencies of diffuse, multi-nodular and 'other' patterns were significantly higher in the received contrast group than in no contrast group. There was no significant difference between the frequency of the segmental pattern or the single nodular pattern in the two groups. There was no significant difference between the uptake patterns with attenuation correction and those without attenuation correction in either the received contrast group or no contrast group.

CONCLUSION

Normal FDG uptake in the large bowel may show various degrees and patterns of uptake among the colonic segments. Oral contrast agent can cause focal or diffuse increased FDG uptake, which may be induced not only by the high CT density of oral contrast but also by an accelerated physiologic reaction of the large bowel.

Intensive Care Complications in Liver and Multivisceral Transplantation

The complications concerning liver and intestinal transplant surgery have relevance for the field of intensive care because they share some characteristics with those following complex long-term surgery. Thus, in this article we shall try to describe complications that are specific to liver and multivisceral transplants. A review of the existing literature on this topic reveals a large number of studies dedicated to early as well as late surgical complications, and immunosuppressive treatment, while there are far fewer contributions describing complications exclusively concerning intensive care. We shall thus attempt to focus on certain aspects where, besides the literature data, we have personal experience. In particular we want to underline the implications of failure in the functional recovery of the graft; alterations in water, electrolyte, and glycemic balance; as well as neurological, respiratory, renal, nutritional, and infective complications.