Liver Maximum Capacity: A Novel Test to Accurately Diagnose Different Stages of Liver Fibrosis

Intestinal failure-associated liver disease: Current challenges in screening, diagnosis, and parenteral nutrition considerations

Intestinal failure-associated liver disease (IFALD) is a serious life-limiting complication that can occur throughout the clinical course of intestinal failure and its management by parenteral nutrition (PN). Despite this, there is a lack of a standardized definition for IFALD, which makes this insidious condition increasingly difficult to screen and diagnose in clinical practice. Attenuating the progression of liver disease before the onset of liver failure is key to improving morbidity and mortality in these patients. This requires timely detection and promptly addressing reversible factors. Although there are various noninvasive tools available to the clinician to detect early fibrosis or cirrhosis in various chronic liver disease states, these have not been validated in the patient population with IFALD. Such tools include biochemical composite scoring systems for fibrosis, transient elastography, and dynamic liver function tests. This review article aims to highlight the existing real need for an accurate, reproducible method to detect IFALD in its early stages. In addition, we also explore the role PN plays in the pathogenesis of this complex multifactorial condition. Various aspects of PN administration have been implicated in the etiology of IFALD, including the composition of the lipid component, nutrient excess and deficiency, and infusion timing. We aim to highlight the clinical relevance of these PN-associated factors in the development of IFALD and how these can be managed to mitigate the progression of IFALD.

Current Trends in Surgical Management of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide. Surgical management, including hepatic resection, liver transplantation, and ablation, offers the greatest potential for a curative approach. This review aims to discuss recent advancements in HCC surgery and identify unresolved issues in the field. Treatment selection relies on the BCLC staging system, with surgical therapies primarily recommended for early-stage disease. Recent studies have shown that patients previously considered unresectable, such as those with portal vein tumor thrombus and uncomplicated portal hypertension, may benefit from hepatic resection. Minimally invasive surgery and improved visualization techniques are also explored, alongside new techniques for optimizing future liver remnant, ex vivo resection, and advancements in hemorrhage control. Liver transplantation criteria, particularly the long-standing Milan criteria, are critically examined. Alternative criteria proposed and tested in specific regions are presented. In the context of organ shortage, bridging therapy plays a critical role in preventing tumor progression and maintaining patients eligible for transplantation. Lastly, we explore emerging ablation modalities, comparing them with the current standard, radiofrequency ablation. In conclusion, this comprehensive review provides insights into recent trends and future prospects in the surgical management of HCC, highlighting areas that require further investigation.

Characteristics and Long-Term Outcome of 535 Patients with Autoimmune Hepatitis-The 20-Year Experience of a High-Volume Tertiary Center

Background and aims: Autoimmune hepatitis (AIH) is a complex and progressive inflammatory liver disease characterized by immune-mediated destruction of the liver parenchyma, hypergammaglobulinemia, the presence of circulating autoantibodies, and good response to immunosuppressive therapy. Since the prevalence of AIH is relatively rare, data on the clinical course and the long-term outcome are scarce. Patients and methods: We retrospectively analyzed the data of 535 well-documented AIH patients treated at the University Hospital Essen between 2000 and 2020. Results: The majority of patients were middle-aged females (75% women, mean age 45 years) with AIH type 1 (97%). Approximately 32% of patients were diagnosed with cirrhosis due to AIH, 29% had concomitant autoimmune (predominantly autoimmune thyroiditis), and 10% had psychiatric diseases, respectively. Skin tumors were the most common malignant diseases (47% of all tumors), while hepatocellular carcinoma rarely occurred (only six cases). Overall long-term mortality and liver-associated mortality were 9.16% and 4.67%, respectively. However, long-term survival was strongly associated with disease remission. Conclusions: Although AIH is a silent disease and cirrhosis is present in many cases, a favorable long-term prognosis can be achieved by consequent immunosuppressive therapy. The incidence of (liver-associated) complications seems to be lower in comparison to other etiologies, such as viral hepatitis or NASH, and mainly depends on the long-term side effects of immunosuppressive therapy.

Time to surgery is not an oncological risk factor in HCC patients undergoing liver resection

PURPOSE

Given limitations of the health care systems in case of unforeseeable events, e.g., the COVID pandemic as well as trends in prehabilitation, time from diagnosis to surgery (time to surgery, (TTS)) has become a research issue in malignancies. Thus, we investigated whether TTS is associated with oncological outcome in HCC patients undergoing surgery.

METHODS

A monocentric cohort of 217 patients undergoing liver resection for HCC between 2009 and 2021 was analyzed. Individuals were grouped according to TTS and compared regarding clinical characteristics. Overall survival (OS) and recurrence-free survival (RFS) was compared using Kaplan-Meier analysis and investigated by univariate and multivariable Cox regressions.

RESULTS

TTS was not associated with OS (p=0.126) or RFS (p=0.761) of the study cohort in univariate analysis. In multivariable analysis age (p=0.028), ASA (p=0.027), INR (0.016), number of HCC nodules (p=0.026), microvascular invasion (MVI; p<0.001), and postoperative complications (p<0.001) were associated with OS and INR (p=0.005), and number of HCC nodules (p<0.001) and MVI (p<0.001) were associated with RFS. A comparative analysis of TTS subgroups was conducted (group 1, ≤30 days, n=55; group 2, 31-60 days, n=79; group 3, 61-90 days, n=45; group 4, >90 days, n=38). Here, the median OS were 62, 41, 38, and 40 months (p=0.602 log rank) and median RFS were 21, 26, 26, and 25 months (p=0.994 log rank). No statistical difference regarding oncological risk factors were observed between these groups.

CONCLUSION

TTS is not associated with earlier tumor recurrence or reduced overall survival in surgically treated HCC patients.

Liver Function-How to Screen and to Diagnose: Insights from Personal Experiences, Controlled Clinical Studies and Future Perspectives

Acute and chronic liver disease is a relevant problem worldwide. Liver function plays a crucial role in the course of liver diseases not only in estimating prognosis but also with regard to therapeutic interventions. Within this review, we discuss and evaluate different tools from screening to diagnosis and give insights from personal experiences, controlled clinical studies and future perspectives. Finally, we offer our novel diagnostic algorithm to screen patients with presumptive acute or chronic liver disease in the daily clinical routine.

Immunomodulation by Hemoadsorption—Changes in Hepatic Biotransformation Capacity in Sepsis and Septic Shock: A Prospective Study

Background: Sepsis is often associated with liver dysfunction, which is an indicator of poor outcomes. Specific diagnostic tools that detect hepatic dysfunction in its early stages are scarce. So far, the immune modulatory effects of hemoadsorption with CytoSorb^® on liver function are unclear. Method: We assessed the hepatic function by using the dynamic LiMAx^® test and biochemical parameters in 21 patients with sepsis or septic shock receiving CytoSorb^® in a prospective, observational study. Points of measurement: T₁: diagnosis of sepsis or septic shock; T₂ and T₃: 24 h and 48 h after the start of CytoSorb^®; T₄: 24 h after termination of CytoSorb^®. Results: The hepatic biotransformation capacity measured by LiMAx^® was severely impaired in up to 95 % of patients. Despite a rapid shock reversal under CytoSorb^®, a significant improvement in LiMAx^® values appeared from T₃ to T₄. This decline and recovery of liver function were not reflected by common parameters of hepatic metabolism that remained mostly within the normal range. Conclusions: Hepatic dysfunction can effectively and safely be diagnosed with LiMAx^® in ventilated ICU patients under CytoSorb^®. Various static liver parameters are of limited use since they do not adequately reflect hepatic dysfunction and impaired hepatic metabolism.

Clinical implications of hepatic structure and function evaluation based on vibration-controlled transient elastography and liver maximum function capacity test in patients with nonalcoholic fatty liver disease

BACKGROUND AND AIMS

Transient elastography [vibration-controlled transient elastography (VCTE)] noninvasively guides risk stratification in patients with nonalcoholic fatty liver disease (NAFLD). Patients with nonalcoholic steatohepatitis (NASH) and fibrosis can be identified using the FAST-score. The liver maximum function test (LiMAx) could be helpful in more precise risk stratification. This pilot study evaluated VCTE, FAST-score, and LiMAx in NAFLD patients.

METHODS

NAFLD patients prospectively underwent VCTE and LiMAx. The cutoffs for high fibrosis risk were 9.3/9.6 kPa (M/XL-probe) and 331 dB/m for steatosis. A FAST-score greater than 0.67 was used to identify patients with NASH and LiMAx values below 315 μg/kg/h for impaired liver function.

RESULTS

In total, 57 NAFLD patients (BMI 32 ± 6 kg/m2; 60% diabetes) were included. High risk for fibrosis and steatosis was observed in 26/57 and 28/57 cases, respectively. Overall, 19/57 patients presented impaired liver function. However, 14/26 of patients with a high risk for fibrosis had impaired liver function compared to 5/31 of those without (P = 0.0026). Similarly, 12/18 patients at high risk for NASH had impaired liver function compared to 7/39 without (P < 0.001). The subgroup with diabetes had a liver stiffness a factor of 1.8 higher, FAST-score was 0.13 higher and LiMAx values were 66 μg/kg/h lower compared to nondiabetics.

CONCLUSION

There is a significant correlation between the functional liver capacity (LiMAx) and the structural liver assessment by VCTE. In cases with high liver stiffness or FAST-score, low LiMAx results may identify NAFLD patients at risk for disease progression and reduce the risk of false-positive categorization.

The role of re-resection in recurrent hepatocellular carcinoma

Purpose

While liver resection is a well-established treatment for primary HCC, surgical treatment for recurrent HCC (rHCC) remains the topic of an ongoing debate. Thus, we investigated perioperative and long-term outcome in patients undergoing re-resection for rHCC in comparative analysis to patients with primary HCC treated by resection.

Methods

A monocentric cohort of 212 patients undergoing curative-intent liver resection for HCC between 2010 and 2020 in a large German hepatobiliary center were eligible for analysis. Patients with primary HCC (n = 189) were compared to individuals with rHCC (n = 23) regarding perioperative results by statistical group comparisons and oncological outcome using Kaplan–Meier analysis.

Results

Comparative analysis showed no statistical difference between the resection and re-resection group in terms of age (p = 0.204), gender (p = 0.180), ASA category (p = 0.346) as well as main preoperative tumor characteristics, liver function parameters, operative variables, and postoperative complications (p = 0.851). The perioperative morbidity (Clavien-Dindo ≥ 3a) and mortality were 21.7% (5/23) and 8.7% (2/23) in rHCC, while 25.4% (48/189) and 5.8% (11/189) in primary HCC, respectively (p = 0.851). The median overall survival (OS) and recurrence-free survival (RFS) in the resection group were 40 months and 26 months, while median OS and RFS were 41 months and 29 months in the re-resection group, respectively (p = 0.933; p = 0.607; log rank).

Conclusion

Re-resection is technically feasible and safe in patients with rHCC. Further, comparative analysis displayed similar oncological outcome in patients with primary and rHCC treated by liver resection. Re-resection should therefore be considered in European patients diagnosed with rHCC.

Limitations of Nerve Fiber Density as a Prognostic Marker in Predicting Oncological Outcomes in Hepatocellular Carcinoma

It has been shown that the presence and density of nerve fibers (NFs; NFD) in the tumor microenvironment (TME) may play an important prognostic role in predicting long-term oncological outcomes in various malignancies. However, the role of NFD in the prognosis of hepatocellular carcinoma (HCC) is yet to be explored. To this end, we aimed to investigate the impact of NFs on oncological outcomes in a large European single-center cohort of HCC patients. In total, 153 HCC patients who underwent partial hepatectomy in a curative-intent setting between 2010 and 2021 at our university hospital were included in this study. Group comparisons between patients with and without NFs were conducted and the association of recurrence-free survival (RFS) and overall survival (OS) with the presence of NFs and other clinico-pathological variables were determined by univariate and multivariable Cox regression models. Patients with NFs in the TME presented with a median OS of 66 months (95% CI: 30−102) compared to 42 months (95% CI: 20−63) for patients without NFs (p = 0.804 log-rank). Further, RFS was 26 months (95% CI: 12−40) for patients with NFs compared to 18 months (95% CI: 9−27) for patients without NFs (p = 0.666 log-rank). In a subgroup analysis, patients with NFD ≤ 5 showed a median OS of 54 months (95% CI: 11−97) compared to 48 months (95% CI: 0−106) for the group of patients with NFD > 5 (p = 0.787 log-rank). Correspondingly, the RFS was 26 months (95% CI: 10−42) in patients with NFD ≤ 5 and 29 months (95% CI: 14−44) for the subcohort with NFD > 5 (p = 0.421 log-rank). Further, group comparisons showed no clinico-pathological differences between patients with NFs (n = 76) and without NFs (n = 77) and NFs were not associated with OS (p = 0.806) and RFS (p = 0.322) in our Cox regression models. In contrast to observations in various malignancies, NFs in the TME and NFD are not associated with long-term oncological outcomes in HCC patients undergoing surgery.

Expanding donor pool for live donor liver transplantation: utilization of donors with non-alcoholic steatohepatitis after optimization

INTRODUCTION

Potential live liver donors with non-alcoholic steatohepatitis (NASH) are rejected upfront for donation in live donor liver transplantation (LDLT). Herein, we share our experience of the feasibility of live liver donation in donors with NASH after successful donor optimization.

MATERIALS AND METHODS

Prospectively collected data of 410 consecutive donor hepatectomies from June 2011 to January 2018 were analyzed.

RESULTS

During the study period, NASH was diagnosed histopathologically in 17 donors. Four donors were rejected in view of grade 2 fibrosis on histology. Out of remaining 13 donors, six became eligible for donation following lifestyle changes, dietary modifications, and target weight reduction of ≥5%. Reversal of NASH was confirmed on repeat liver biopsy in all the 6 donors. Five out of 6 underwent right lobe (without MHV) donor hepatectomies, while one had left lobe donation. These donors had significantly higher peak bilirubin levels in the immediate post-operative period as compared to other non-NASH donors (4.00 ± 0.32 vs. 2.57 ± 1.77 mg/dL, p = 0.043). In addition, post-hepatectomy normalization of hyperbilirubinemia, if any, was slower in donors with NASH (7 ± 1.3 vs. 5 ± 1.7 days, p = 0.016). However, none of these donors had post-hepatectomy liver failure. All these donors were discharged after an average hospital stay of 8 ± 1.7 days. Their respective recipients had uneventful post-operative courses without complications. Both the recipients and donors are having satisfactory liver functions after 46.7 ± 10.2 months of follow-up.

CONCLUSION

Scrupulous selection of live liver donors with NASH can open a door for expanding the organ pool in LDLT after a successful donor optimization program.

Enzymatic liver function measured by LiMAx is superior to current standard methods in predicting transplant-free survival after TIPS implantation

Transjugular intrahepatic portosystemic shunt (TIPS) is one of the main treatment options in patients with decompensated liver cirrhosis but is still associated with partly severe complications. For adequate patient selection, prognostic parameters are of crucial importance. The liver maximum capacity (LiMAx) breath test measures enzymatic liver function and could potentially represent an efficient prognostic marker. We therefore aimed to assess the role of LiMAx in predicting survival of TIPS patients in a prospective analysis. LiMAx was performed for patients who underwent TIPS implantation between October 2016 and February 2018. Associations with transplant-free survival after 24 weeks were assessed by logistic regression. A total number of 30 patients were included, of whom seven received liver transplantation (N = 2) or died (N = 5) during follow-up. LiMAx values after (P = 0.01, OR = 1.24, 95% CI = 1.04-1.47) and before (P = 0.03, OR 1.21, 95% CI = 1.02-1.43) TIPS implantation and MELD score (P = 0.03, OR = 0.79, 95% CI = 0.63-0.98) were significantly associated with transplant-free survival according to univariate logistic regression. In AUROC analysis, LiMAx at day one after TIPS (sensitivity 85.7%, specificity 78.3%, AUROC 0.85, cut-off ≤ 165 µg/kg/h), LiMAx value at the day before TIPS (sensitivity 100%, specificity 73.9%, AUROC 0.82, cut-off ≤ 205 µg/kg/h) and MELD score (sensitivity 71.4%, specificity 73.9%, AUROC 0.82, cut-off ≥ 15) had the highest prognostic accuracy. LiMAx values prior and after TIPS procedure seem to be good prognostic parameters regarding prediction of transplant-free survival of patients undergoing TIPS implantation.

Development and Validation of a Novel Scoring System for Noninvasive Nonalcoholic Steatohepatitis Detection in Bariatric Patients

INTRODUCTION

Nonalcoholic fatty liver disease covers a broad spectrum. Simple steatosis has usually a benign course while nonalcoholic steatohepatitis (NASH) can progress into hepatocellular carcinoma, and cirrhosis. Therefore, differentiating patients with benign steatosis and NASH is crucial. Liver biopsy, the usual gold standard for NASH diagnosis, cannot be used as a screening method due to its associated risks. This is especially problematic for obese patients with a prevalence of nonalcoholic fatty liver disease (NAFLD) in >80% of patients. The aim of this study was therefore to develop and validate a noninvasive NASH screening test in a cohort of high-risk, morbidly obese patients.

METHODS

This prospective study examined diagnostic accuracy in accordance with STARD guidelines. 112 liver biopsies were consecutively assigned to either a training or validation cohort. Using the Bedossa histological scoring system, the cohorts were subdivided into NASH versus NAFLD/No NAFLD. Predictors of NASH were evaluated with receiver operating characteristic (ROC) curves. A model was then constructed using a backward stepwise logistic regression and evaluated in an independent validation cohort.

RESULTS

53.5% of the patients had NASH and 4 patients had cirrhosis. Mean body mass index (BMI) was 49.8 ± 7.5 kg/m2. Backward stepwise logistic regression identified 4 parameters associated with the presence of NASH: alanin-aminotransferase, albumin, BMI, and triglycerides. The noninvasive NASH detection score (NI-NASH-DS) had an ROC of 0.851 and 0.727 in the training and validation cohorts, respectively. Sensitivity and specificity were 77.1% and 88% in the training cohort and 88% and 48% in the validation cohort which was much better than the established noninvasive scores.

DISCUSSION/CONCLUSION

The NI-NASH-DS is easy-to-use, inexpensive, and noninvasive and can reliably detect NASH in patients with morbid obesity. Due to its simplicity, it can be used frequently and repeatedly.

Volume-Function Analysis (LiMAx Test) in Patients with HCC and Cirrhosis Undergoing TACE-A Feasibility Study

BACKGROUND

Transarterial chemoembolization (TACE) is an important therapy for hepatocellular carcinoma (HCC) in cirrhosis. In particular in advanced cirrhosis, post-TACE hepatic failure liver (PTHF) failure may develop. Currently, there is no standardization for the periinterventional risk assessment. The liver maximum capacity (LiMAx) test assesses the functional liver capacity, but has not been investigated in this setting.

AIMS

The aim of this study was to prospectively evaluate periinterventional LiMAx and CT volumetry measurements in patients with cirrhosis and HCC undergoing repetitive TACE.

METHODS

From 06/2016 to 11/2017, eleven patients with HCC and cirrhosis undergoing TACE were included. LiMAx measurements (n = 42) were conducted before and after each TACE. Laboratory parameters were correlated with the volume-function data.

RESULTS

The median LiMAx levels before (276 ± 166 µg/kg/h) were slightly reduced after TACE (251 ± 122 µg/kg/h; p = 0.08). This corresponded to a median drop of 7.1%. Notably, there was a significant correlation between LiMAx levels before TACE and bilirubin (but not albumin nor albumin-bilirubin [ALBI] score) increase after TACE (p = 0.02, k = 0.56). Furthermore, a significantly higher increase in bilirubin in patients with LiMAx ≤ 150 µg/kg/h was observed (p = 0.011). LiMAx levels at different time points in single patients were similar (p = 0.2).

CONCLUSION

In our prospective pilot study in patients with HCC and cirrhosis undergoing multiple TACE, robust and reliable LiMAx measurements were demonstrated. Lower LiMAx levels before TACE were associated with surrogate markers (bilirubin) of liver failure after TACE. Specific subgroups at high risk of PTHF should be investigated. This might facilitate the future development of strategies to prevent occurrence of PTHF.

Prognostic evaluation of HCC patients undergoing surgical resection: an analysis of 8 different staging systems

Purpose

No consensus exists regarding the most appropriate staging system to predict overall survival (OS) for hepatocellular carcinoma (HCC) in surgical candidates. Thus, we aimed to determine the prognostic ability of eight different staging systems in a European cohort of patients undergoing liver resection for HCC.

Methods

Patients resected for HCC between 2010 and 2019 at our institution were analyzed with Kaplan-Meier and Cox regression analyses. Likelihood ratio (LR) χ² (homogeneity), linear trend (LT) χ² (discriminatory ability), and Akaike Information Criterion (AIC, explanatory ability) were used to determine the staging system with the best overall prognostic performance.

Results

Liver resection for HCC was performed in 160 patients. Median OS was 39 months (95% confidence interval (CI): 32–46 months) and median RFS was 26 months (95% CI: 16–34 months). All staging systems (BCLC, HKLC, Okuda, CLIP, ITA.LI.CA staging and score, MESH, and GRETCH) showed significant discriminatory ability regarding OS, with ITA.LI.CA score (LR χ² 30.08, LT χ² 13.90, AIC 455.27) and CLIP (LR χ² 28.65, LT χ² 18.95, AIC 460.07) being the best performing staging systems.

Conclusions

ITA.LI.CA and CLIP are the most suitable staging system to predict OS in European HCC patients scheduled for curative-intent surgery.

Assessing Non-Invasive Liver Function in Patients with Intestinal Failure Receiving Total Parenteral Nutrition-Results from the Prospective PNLiver Trial

Liver abnormalities in intestinal failure (IF) patients receiving parenteral nutrition (PN) can progress undetected by standard laboratory tests to intestinal failure associated liver disease (IFALD). The aim of this longitudinal study is to evaluate the ability of non-invasive liver function tests to assess liver function following the initiation of PN. Twenty adult patients with IF were prospectively included at PN initiation and received scheduled follow-up assessments after 6, 12, and 24 months between 2014 and 2019. Each visit included liver assessment (LiMAx [Liver Maximum Capacity] test, ICG [indocyanine green] test, FibroScan), laboratory tests (standard laboratory test, NAFLD [non-alcoholic fatty liver disease] score, FIB–4 [fibrosis-4] score), nutritional status (bioelectrical impedance analysis, indirect calorimetry), and quality of life assessment. The patients were categorized post-hoc based on their continuous need for PN into a reduced parenteral nutrition (RPN) group and a stable parenteral nutrition (SPN) group. While the SPN group (n = 9) had significantly shorter small bowel length and poorer nutritional status at baseline compared to the RPN group (n = 11), no difference in liver function was observed between the distinct groups. Over time, liver function determined by LiMAx did continuously decrease from baseline to 24 months in the SPN group but remained stable in the RPN group. This decrease in liver function assessed with LiMAx in the SPN group preceded deterioration of all other investigated liver function tests during the study period. Our results suggest that the liver function over time is primarily determined by the degree of intestinal failure. Furthermore, the LiMAx test appeared more sensitive in detecting early changes in liver function in comparison to other liver function tests.

Enzymatic liver function measured by LiMAx - a reliable diagnostic and prognostic tool in chronic liver disease

Chronic liver disease (CLD) is a major cause of morbidity and mortality worldwide. Non-invasive assessment of hepatic disease severity represents a relevant issue to further improve clinical management and therapeutic treatment. We retrospectively compared the diagnostic and prognostic performance of different non-invasive tools (LiMAx, transient elastography (TE), and biomarkers) in detecting different severity stages during the course of CLD. Patients were divided into four groups based on clinical parameters: (1) patients without CLD (control group), (2) patients suffering from CLD without having cirrhosis, (3) patients with CLD and compensated cirrhosis, and finally, (4) patients with CLD and decompensated cirrhosis. Patients with acute liver failure were excluded from the analysis. A total of 464 patients who underwent LiMAx measurement at the University Clinic of Essen between 10/2016 and 11/2017 were included in this study. Distribution of the different groups were n = 72 patients for group 1, n = 134 patients for group 2, n = 160 patients for group 3, and n = 98 patients for group 4, respectively. Median LiMAx values significantly declined with respect to increasing degree of CLD: (1) 510 µg/h/kg, (2) 390 µg/h/kg, (3) 264 µg/h/kg, and (4) 151 µg/h/kg (p < 0.001). When comparing the diagnostic accuracy of the LiMAx test in detecting patients with presence of cirrhosis (groups 1 and 2 vs. groups 3 and 4), an AUROC of 0.942 was found (cut-off 322 µg/h/kg, sensitivity 86.1%, specificity 91.3%, p < 0.0001). LiMAx was superior to TE and serum biomarkers in predicting patients’ outcome by 90-day mortality (AUROC 0.811, p < 0.001). Enzymatic liver function measured by LiMAx was closely associated with different severity stages of CLD and was a reliable diagnostic and prognostic tool with an accuracy comparable to current standard methods.

Non-invasive structure-function assessment of the liver by 2D time-harmonic elastography and the dynamic Liver MAximum capacity (LiMAx) test

BACKGROUND AND AIM

Accurate assessment of structural and functional characteristics of the liver could improve the diagnosis and the clinical management of patients with chronic liver diseases. However, the structure-function relationship in the progression of chronic liver disease remains elusive. The aim of this study is the combined measurement of liver function by the ¹³ C-methacetin Liver MAximum capacity (LiMAx) test and tissue-structure related stiffness by 2D time-harmonic elastography for the assessment of liver disease progression.

METHODS

LiMAx test and time-harmonic elastography were applied, and the serological scores fibrosis 4 index and aspartate aminotransferase to platelet ratio index were calculated in patients with chronic liver diseases (n = 75) and healthy control subjects (n = 22). In 47 patients who underwent surgery, fibrosis was graded by histological examination of the resected liver tissue.

RESULTS

LiMAx values correlated negatively with liver stiffness (r = -0.747), aminotransferase to platelet ratio index (r = -0.604), and fibrosis 4 (r = -0.573). Median (interquartile range) LiMAx values decreased with fibrosis progression from 395 μg/kg/h (371-460 μg/kg/h) in participants with no fibrosis to 173 μg/kg/h (126-309 μg/kg/h) in patients with severe fibrosis. Median liver stiffness increased progressively with the stage of fibrosis from no fibrosis (1.56 m/s [1.52-1.63 m/s]) to moderate fibrosis (1.60 m/s [1.54-1.67 m/s]) to severe fibrosis (1.85 m/s [1.76-1.92 m/s]).

CONCLUSION

Our findings show that structural changes in the liver due to progressing liver diseases and reflected by increased tissue stiffness correlate with a functional decline of the organ as reflected by a decreased metabolic capacity of the liver.

Noninvasive Evaluation of Liver Function in Morbidly Obese Patients

Background

More than half of the obese patients develop nonalcoholic fatty liver disease (NAFLD), which may further progress to nonalcoholic steatohepatitis (NASH) and cirrhosis. The aim of this study was to assess alterations in liver function in obese patients with a noninvasive liver function test.

Methods

In a prospective cohort study 102 morbidly obese patients undergoing bariatric surgery were evaluated for their liver function. Liver function capacity was determined by the LiMAx® test (enzymatic capacity of cytochrome P450 1A2). Liver biopsy specimens were obtained intraoperatively and classified according to the NAFLD Activity Score (NAS). NASH clinical score was additionally calculated from laboratory and clinical parameters.

Results

Median liver function capacity was 286 (IQR = 141) μg/kg/h. 27% of patients were histologically categorized as definite NASH, 39% as borderline, and 34% as not NASH. A significant correlation was observed between liver function capacity and NAS (r = −0.492; p < 0.001). The sensitivity and specificity of the LiMAx® test to distinguish between definite NASH and not NASH were 85.2% and 82.9% (AUROC 0.859), respectively. According to the NASH clinical scoring system, 14% were classified as low risk, 31% as intermediate, 26% as high, and 29% as very high risk. Liver function capacity is also significantly correlated with the NASH clinical scoring system (r = −0.411; p < 0.001).

Conclusions

Obese patients show a diminished liver function capacity, especially those suffering from type 2 diabetes. The liver function capacity correlates with histological and clinical scoring systems. The LiMAx® test may be a valuable tool for noninvasive screening for NASH in obese patients.