Non-invasive methods for the diagnosis of nonalcoholic fatty liver disease

Novel serum biomarkers modified by the body mass index z-score for the detection of liver fibrosis and steatosis in children with chronic hepatitis C

BACKGROUND

There is a need for validation of noninvasive alternatives to liver biopsy for the evaluation of fibrosis in children with chronic hepatitis C (CHC). The aim of this study was to evaluate the diagnostic performance of serum biomarkers modified by the body mass index z-score (BMI z-score) for the detection of fibrosis and steatosis in children with CHC.

METHODS

Thirty children aged 9.4 ± 3.7 years (14 males, 16 females) with CHC underwent liver biopsy. Fibrosis was scored using a 5-point METAVIR scale (≥2 = significant fibrosis). For all the children, the following noninvasive markers were calculated: The aspartate transaminase (AST)-to-platelets ratio index (APRI), the modified APRI (M-APRI: BMI z-score × APRI), the Fibrosis-4 index (FIB-4), the modified FIB-4 (M-FIB-4: BMI z-score × FIB-4), and a novel marker, B-AST (BMI z-score × AST). The area under the receiver operator characteristic curve (AUROC) was calculated to detect significant fibrosis and steatosis.

RESULTS

In the histopathological evaluation, 22/30 (73%) patients presented with fibrosis, and 8/30 (27%) presented with steatosis. For the detection of significant fibrosis, the AUROCs for M-APRI, M-FIB-4 and B-AST were 0.842, 0.823, and 0.848, respectively. For significant steatosis, the AUROCs were more than 0.9 for all markers that included the BMI z-score. B-AST, with a cut-off of 92.8, showed 71% sensitivity and 95% specificity for detecting significant fibrosis. For predicting severe steatosis, B-AST had 100% sensitivity and 92% specificity. Negative values of all three markers that included BMI z-scores excluded all patients with both significant fibrosis and significant steatosis.

CONCLUSIONS

Including the BMI z-score in serum biomarker formulas enhances their diagnostic ability to detect significant fibrosis and steatosis. B-AST may thus act as an effective alternative to liver biopsy.

Nonalcoholic Fatty Liver Disease: The New Complication of Type 2 Diabetes Mellitus

Nonalcoholic fatty liver disease (NAFLD) is increasingly common in patients with type 2 diabetes mellitus (T2DM), with an estimated prevalence of 60% to 80%. The relationship of NAFLD and T2DM is complex, with each condition negatively affecting the other. Although NAFLD is associated with more metabolic and cardiovascular complications and worse hyperglycemia, T2DM accelerates the progression of liver disease in NAFLD. Despite the high prevalence and serious clinical implications, NAFLD is usually overlooked in clinical practice. This article focuses on understanding the relationship between NAFLD and T2DM, to provide better care for these complex patients.

Associations Between Lifestyle Characteristics and the Presence of Nonalcoholic Fatty Liver Disease: A Case-Control Study

BACKGROUND

Dietary and physical activity (PA) habits have been suggested as important factors for nonalcoholic fatty liver disease (NAFLD). Published data are mainly focused on the effect of either diet or exercise, whereas data on other aspects like sleep remain sparse. The aim of this study was to explore potential associations between dietary intake, PA, and sleeping habits, and the presence of NAFLD.

METHODS

One hundred patients with ultrasound-proven NAFLD and 55 healthy controls matched for age, sex, and body mass index were included. Dietary habits were assessed through a semiquantitative validated food frequency questionnaire. PA level was assessed with a validated questionnaire. Total night sleep hours and duration of midday rest were also recorded. Optimal sleep duration was defined as sleep hours ≥7 and ≤9 hr/day.

RESULTS

Patients compared to controls consumed less vegetables and nuts, more sweets, drank less coffee and alcohol (all P < 0.05), and exhibited a lower level of PA (P = 0.006). PA level [odds ratio (OR) per 100 metabolic equivalent of task-min/day = 0.74, 95% confidence interval (CI) 0.61-0.89, P = 0.002] was associated with lower probability of having NAFLD, whereas sweets consumption (OR = 2.13, 95% CI 1.22-3.71, P = 0.008) was associated with increased probability, after adjusting for several confounders, including body weight status. Optimal sleep duration was marginally and inversely associated with NAFLD presence (OR = 0.38, 95% CI 0.14-1.01, P = 0.05).

CONCLUSION

Higher PA level and optimal sleep duration are associated with lower likelihood, whereas sweets consumption is associated with higher likelihood of having NAFLD. These associations are independent of body weight status and energy intake.

MRI and MRE for non-invasive quantitative assessment of hepatic steatosis and fibrosis in NAFLD and NASH: Clinical trials to clinical practice

Non-alcoholic fatty liver disease (NAFLD) represents one of the most common causes of chronic liver disease, and its prevalence is rising worldwide. The occurrence of non-alcoholic steatohepatitis (NASH) is associated with a substantial increase in disease related morbidity and mortality. Accordingly, there has been a surge of innovation surrounding drug development in an effort to off-set the natural progression and long-term risks of this disease. Disease assessment within clinical trials and clinical practice for NAFLD is currently done with liver biopsies. Liver biopsy-based assessments, however, remain imprecise and are not without cost or risk. This carries significant implications for the feasibility and costs of bringing therapeutic interventions to market. A need therefore arises for reliable and highly accurate surrogate end-points that can be used in phase 2 and 3 clinical trials to reduce trial size requirements and costs, while improving feasibility and ease of implementation in clinical practice. Significant advances have now been made in magnetic resonance technology, and magnetic resonance imaging (MRI) and elastrography (MRE) have been demonstrated to be highly accurate diagnostic tools for the detection of hepatic steatosis and fibrosis. In this review article, we will summarize the currently available evidence regarding the use of MRI and MRE among NAFLD patients, and the evolving role these surrogate biomarkers will play in the rapidly advancing arena of clinical trials in NASH and hepatic fibrosis. Furthermore, we will highlight how these tools can be readily applied to routine clinical practice, where the growing burden of NAFLD will need to be met with enhanced monitoring algorithms.

C-X-C motif chemokine 10 in non-alcoholic steatohepatitis: role as a pro-inflammatory factor and clinical implication

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. Non-alcoholic steatohepatitis (NASH) is a more severe form of NAFLD and causes subsequent pathological changes including cirrhosis and hepatocellular carcinoma. Inflammation is the key pathological change in NASH and involves a series of cytokines and chemokines. The C-X-C motif chemokine 10 (CXCL10), which is known as a pro-inflammation chemokine, was recently proven to play a pivotal role in the pathogenesis of NASH. Hepatic CXCL10 is mainly secreted by hepatocytes and liver sinusoidal endothelium. By binding to its specific receptor CXCR3, CXCL10 recruits activated CXCR3+ T lymphocytes and macrophages to parenchyma and promotes inflammation, apoptosis and fibrosis. The circulating CXCL10 level correlates with the severity of lobular inflammation and is an independent risk factor for NASH patients. Thus, CXCL10 may be both a potential prognostic tool and a therapeutic target for the treatment of patients with NASH. The aim of this review is to highlight the growing advances in basic knowledge and clinical interest of CXCL10 in NASH to propagate new insights into novel pharmacotherapeutic avenues.

Influence of Fatty Liver on the Severity and Clinical Outcome in Acute Pancreatitis

Acute pancreatitis (AP) is a common disease in the department of gastroenterology with variable severity, from being mild and self-limited to severe and fatal. The early diagnosis and accurate prediction of AP severity are of great importance. Our primary observation showed that fatty liver (FL) was frequently detected in patients with AP. In this retrospective study, we aimed to evaluate the relation between FL and the severity and outcomes of AP. The medical records of 2671 patients with AP were reviewed retrospectively, and characteristics of AP patients were recorded. FL was assessed by abdominal CT scan, and AP patients were categorized by the occurrence of FL for the analysis. The variation of mortality, clinical severity and the appearance of CT were analyzed between the non-FL group and FL groups. Compared with patients without FL, an obviously higher rate of death and higher frequency of severe AP (SAP) and necrotizing AP (ANP) were observed in patients with FL, as well as the incidence of local complications and systemic complications. Taking obesity into consideration, a higher rate of death and more severe AP were found in patients with FL, no matter whether they were obese or not. Alcoholic fatty liver (AFL) and non-alcoholic fatty liver (NAFL) were also separated for comparison in this study; the incidence of ANP and the clinical severity had no significant difference between the AFL and NAFL groups. In conclusion, FL could influence the severity and clinical outcome and may play a prognostic role in AP. This study is of clinical significance, because few reports have been previously issued on FL and AP.

Liver fibrosis in non-alcoholic fatty liver disease - diagnostic challenge with prognostic significance

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the Western world, with a prevalence of 20%. In a subgroup of patients, inflammation, ballooning degeneration of hepatocytes and a varying degree of fibrosis may develop, a condition named non-alcoholic steatohepatitis. Advanced liver fibrosis (stage F3) and cirrhosis (stage F4) are histologic features that most accurately predict increased mortality in both liver-related and cardiovascular diseases. Patients with advanced fibrosis or cirrhosis are at risk for complications such as hepatocellular carcinoma and esophageal varices and should therefore be included in surveillance programs. However, liver disease and fibrosis are often unrecognized in patients with NAFLD, possibly leading to a delayed diagnosis of complications. The early diagnosis of advanced fibrosis in NAFLD is therefore crucial, and it can be accomplished using serum biomarkers (e.g., the NAFLD Fibrosis Score, Fib-4 Index or BARD) or non-invasive imaging techniques (transient elastography or acoustic radiation force impulse imaging). The screening of risk groups, such as patients with obesity and/or type 2 diabetes mellitus, for NAFLD development with these non-invasive methods may detect advanced fibrosis at an early stage. Additionally, patients with a low risk for advanced fibrosis can be identified, and the need for liver biopsies can be minimized. This review focuses on the diagnostic challenge and prognostic impact of advanced liver fibrosis in NAFLD.

Steatosis and hepatitis C

Hepatitis C virus (HCV) infection is a common liver disease worldwide with a high rate of chronicity (75–80%) in infected individuals. The chronic form of HCV leads to steatosis, cirrhosis and hepatocellualr carcinoma. Steatosis is prevalent in HCV patients (55%) due to a combination of viral factors (effect of viral proteins on some of the intracellular pathways) and host factors (overweight, insulin resistance, diabetes mellitus, and alcohol consumption). The response rates to treatment of chronic HCV with pegylated interferon (PEG-IFN) and (in the case of genotype-1 HCV, the most common infecting genotype in the USA) ribavirin (RBV) is low, with a sustained viral response rate ≤ 40%. Adding direct-acting antiviral agents—recently approved by the FDA—to the standard protocol has increased the response rate; however HCV-related end-stage liver disease is still the primary indication for liver transplantation in the USA. The focus of this article is on the interrelation between HCV, steatosis and metabolic syndrome.