Raj Vuppalanchi

Nonalcoholic fatty liver disease and nonalcoholic steatohepatitis: Selected practical issues in their evaluation and management

Nonalcoholic fatty liver disease (NAFLD) is among the most common causes of chronic liver disease in the western world. It is now recognized that these patients have myriad of important co‐morbidities (e.g., diabetes, hypothyroidism and metabolic syndrome). The workup of patients with suspected NAFLD should consist of excluding competing etiologies and systemic evaluation of metabolic comorbidities. NAFLD is histologically categorized into steatosis and steatohepatitis, two states with fairly dichotomous natural history. While significant progress has been made in terms of noninvasively predicting advanced fibrosis, insufficient progress has been made in predicting steatohepatitis. Currently, liver biopsy remains the gold standard for the histological stratification of NAFLD. While sustained weight loss can be effective to treat NASH, it is often difficult to achieve. Foregut bariatric surgery can be quite effective in improving hepatic histology in selected patients without liver failure or significant portal hypertension. Thiazolidinediones have shown promise and the results from the ongoing, large multicenter study should become available soon. Large multicenter studies of CB, receptor anatagonists are also underway but their results will not be available for several years. Several recent studies have highlighted that cardiovascular disease is the single most important cause of morbidity and mortality in this patient population. Conclusion: Health care providers should not only focus on liver disease but also concentrate on aggressively modifying and treating their cardiovascular risk factors. (HEPATOLOGY 2009;49:306‐317.)

Features and Outcomes of 899 Patients With Drug-Induced Liver Injury: The DILIN Prospective Study

BACKGROUND & AIMS The Drug-Induced Liver Injury Network is conducting a prospective study of patients with DILI in the United States. We present characteristics and subgroup analyses from the first 1257 patients enrolled in the study. METHODS In an observational longitudinal study, we began collecting data on eligible individuals with suspected DILI in 2004, following them for 6 months or longer. Subjects were evaluated systematically for other etiologies, causes, and severity of DILI. RESULTS Among 1257 enrolled subjects with suspected DILI, the causality was assessed in 1091 patients, and 899 were considered to have definite, highly likely, or probable DILI. Ten percent of patients died or underwent liver transplantation, and 17% had chronic liver injury. In the 89 patients (10%) with pre-existing liver disease, DILI appeared to be more severe than in those without (difference not statistically significant; P = .09) and mortality was significantly higher (16% vs 5.2%; P < .001). Azithromycin was the implicated agent in a higher proportion of patients with pre-existing liver disease compared with those without liver disease (6.7% vs 1.5%; P = .006). Forty-one cases with latency ≤7 days were caused predominantly by antimicrobial agents (71%). Two most common causes for 60 DILI cases with latency >365 days were nitrofurantoin (25%) or minocycline (17%). There were no differences in outcomes of patients with short vs long latency of DILI. Compared with individuals younger than 65 years, individuals 65 years or older (n = 149) were more likely to have cholestatic injury, although mortality and rate of liver transplantation did not differ. Nine patients (1%) had concomitant severe skin reactions; implicated agents were lamotrigine, azithromycin, carbamazepine, moxifloxacin, cephalexin, diclofenac, and nitrofurantoin. Four of these patients died. CONCLUSIONS Mortality from DILI is significantly higher in individuals with pre-existing liver disease or concomitant severe skin reactions compared with patients without. Additional studies are needed to confirm the association between azithromycin and increased DILI in patients with chronic liver disease. Older age and short or long latencies are not associated with DILI mortality.

Liver injury from herbals and dietary supplements in the U.S. Drug‐Induced Liver Injury Network

The Drug‐Induced Liver Injury Network (DILIN) studies hepatotoxicity caused by conventional medications as well as herbals and dietary supplements (HDS). To characterize hepatotoxicity and its outcomes from HDS versus medications, patients with hepatotoxicity attributed to medications or HDS were enrolled prospectively between 2004 and 2013. The study took place among eight U.S. referral centers that are part of the DILIN. Consecutive patients with liver injury referred to a DILIN center were eligible. The final sample comprised 130 (15.5%) of all subjects enrolled (839) who were judged to have experienced liver injury caused by HDS. Hepatotoxicity caused by HDS was evaluated by expert opinion. Demographic and clinical characteristics and outcome assessments, including death and liver transplantation (LT), were ascertained. Cases were stratified and compared according to the type of agent implicated in liver injury; 45 had injury caused by bodybuilding HDS, 85 by nonbodybuilding HDS, and 709 by medications. Liver injury caused by HDS increased from 7% to 20% (P < 0.001) during the study period. Bodybuilding HDS caused prolonged jaundice (median, 91 days) in young men, but did not result in any fatalities or LT. The remaining HDS cases presented as hepatocellular injury, predominantly in middle‐aged women, and, more frequently, led to death or transplantation, compared to injury from medications (13% vs. 3%; P < 0.05). Conclusions: The proportion of liver injury cases attributed to HDS in DILIN has increased significantly. Liver injury from nonbodybuilding HDS is more severe than from bodybuilding HDS or medications, as evidenced by differences in unfavorable outcomes (death and transplantation). (Hepatology 2014;60:1399–1408)

Patients with Elevated Baseline Liver Enzymes Do Not Have Higher Frequency of Hepatotoxicity from Lovastatin than Those with Normal Baseline Liver Enzymes

Background:It is recommended that lovastatin be avoided in patients with unexplained elevation in transaminase levels. However, there are no studies that evaluated the risk of lovastatin hepatotoxicity in subjects with elevated liver enzymes. Our study tested the hypothesis that patients with elevated liver enzymes are not at higher risk for hepatotoxicity from lovastatin. Methods:Our study consisted of the following three cohorts of patients seen between December 1987 and December 1998: cohort 1: 135 patients with elevated baseline enzymes (aspartate transaminase [AST] >40 IU/L or alanine transaminase [ALT] >35 IU/L) who received lovastatin; cohort 2: 620 patients without elevated liver enzymes who received lovastatin; and cohort 3: 2644 patients with elevated liver enzymes but not prescribed lovastatin. Elevations in liver biochemistries over a 12-month period after lovastatin was prescribed were categorized into mild-moderate or severe elevations and into “Hy’s Rule” based on published criteria. Results:The incidence of mild-moderate elevations and severe elevations in liver biochemistries in cohort 1 were 6.6% and 0%, respectively. Compared with cohort 2, individuals in cohort 1 had higher incidence of mild-moderate elevations (6.6% versus 3%; P = 0.03) but not severe elevations (0% versus 0.3%; P = 0.9). Compared with cohort 3, patients in cohort 1 had similar mild-moderate elevations (6.6% versus 11%; P = 0.2) but lower severe elevations (0% versus 5.5%; P < 0.01). No one in cohorts 1 or 2 developed elevations meeting Hy’s Rule, whereas 3.5% of the patients in cohort 3 exhibited such elevations (P < 0.05 versus cohort 1 or cohort 2). Conclusions:Significant hepatotoxicity from lovastatin was very infrequent in this study, and individuals with elevated baseline liver enzyme levels did not have higher frequency of lovastatin hepatotoxicity than those with normal liver enzyme levels.

Effects of Liver Biopsy Sample Length and Number of Readings on Sampling Variability in Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS Liver biopsy is required to diagnose nonalcoholic steatohepatitis (NASH) in patients with suspected non-alcoholic fatty liver disease (NAFLD); recent studies suggested significant sampling variability. Using percutaneous liver biopsy samples from patients with suspected NAFLD, we examined the relationship between histological yield and length of biopsies, number of cores and number of independent readings. METHODS Three cores of liver tissue were collected, by percutaneous liver biopsy, from each of 50 patients suspected to have NAFLD. The diagnostic yield (percent with definite NASH) and other histological findings from 2 independent, blinded examinations of 2 cores and from all 3 cores combined were assessed. RESULTS Steatosis, lobular inflammation and fibrosis scores were significantly higher when 3 samples were analyzed, compared with 2. However, between groups, there were no significant differences in hepatocyte ballooning, proportion with an NAFLD activity score > or =4 or proportion with definite NASH (57% vs 61%, P = .3). The length of the biopsy sample correlated with percentage of patients found to have definite NASH (29%, 46%, 56%, and 65% in biopsies measuring <10 mm, 10-14 mm, 15-24 mm, and > or =25 mm, respectively; P < .0001). When biopsy specimens were read twice by the same pathologist, the composite of the 2 independent readings yielded a significantly higher yield for several histological features, compared with the first reading. CONCLUSIONS There is a significant relationship between histological yield and sample length and number of independent readings of liver biopsy samples. More studies are needed to optimize the strategy for liver biopsy, to more effectively assess histology in patients with suspected NAFLD.

Dyslipidemia in Patients with Nonalcoholic Fatty Liver Disease

Patients with nonalcoholic fatty liver disease (NAFLD) often have dyslipidemia along with other features of metabolic syndrome such as obesity, diabetes mellitus, and hypertension. The dyslipidemia in NAFLD is characterized by increased serum triglycerides, increased small, dense low-density lipoprotein (LDL nontype A) particles, and low high-density lipoprotein (HDL) cholesterol. The pathogenesis of dyslipidemia in NAFLD is not well understood, but it is likely related to hepatic overproduction of the very low-density lipoprotein particles and dysregulated clearance of lipoproteins from the circulation. There is unequivocal evidence that cardiovascular disease is the most common cause of mortality in patients with NAFLD. Aggressive treatment of dyslipidemia plays a critical role in the overall management of patients with NAFLD. Statins are the first-line agents to treat high cholesterol and their dosage should be adjusted based on achieving therapeutic targets and tolerability. Although all statins appear to be effective in improving cholesterol levels in patients with NAFLD, there is more experience with atorvastatin in patients with NAFLD; furthermore, it is the only statin to date to show a reduced cardiovascular morbidity in patients with NAFLD. The risk for serious liver injury from statins is quite rare and patients with NAFLD are not at increased risk for statin hepatotoxicity. Omega-3 fatty acids are perhaps the first choice to treat hypertriglyceridemia because of their safety, tolerability, and efficacy in improving serum triglycerides, as well as their potential to improve liver disease.

Incidence and Predictors of 30-Day Readmission Among Patients Hospitalized for Advanced Liver Disease

BACKGROUND & AIMS The rate of readmission to the hospital 30 days after discharge (30-day readmission rate) is used as a quality measure for hospitalized patients, but it has not been studied adequately for patients with advanced liver disease. We investigated the incidence and factors that predict this rate and its relationship with mortality at 90 days. METHODS We analyzed data from patients with advanced liver disease who were hospitalized to an inpatient hepatology service at 2 large academic medical centers in 2008. Patients with elective admission and recipients of liver transplants were not included. During the study period, there were 447 patients and a total of 554 eligible admissions. Multivariate analyses were performed to identify variables associated with 30-day readmission and to examine its relationship with mortality at 90 days. RESULTS The 30-day readmission rate was 20%. After adjusting for multiple covariates, readmission within 30 days was associated independently with model for end-stage liver disease scores at discharge (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02-1.09; P = .002), the presence of diabetes (OR, 1.78; 95% CI, 1.07-2.95; P = .027), and male sex (OR, 1.73; 95% CI, 1.03-2.89; P = .038). After adjusting for age, sex, and model for end-stage liver disease score at discharge, the 90-day mortality rate was significantly higher among patients who were readmitted to the hospital within 30 days than those who were not (26.8% vs 9.8%; OR, 2.6; 95% CI, 1.36-5.02; P = .004). CONCLUSIONS Patients with advanced liver disease frequently are readmitted to the hospital within 30 days after discharge; these patients have a higher 90-day mortality rate than those who are not readmitted in 30 days. These data might be used to develop strategies to reduce early readmission of hospitalized patients with cirrhosis.

Presence and significance of microvesicular steatosis in nonalcoholic fatty liver disease

BACKGROUND & AIMS Liver biopsies from patients with nonalcoholic fatty liver disease (NAFLD) sometimes exhibit non-zonal aggregates of hepatocytes with microvesicular steatosis, but its prevalence and significance are unclear. In this study, we have evaluated the frequency of microvesicular steatosis and assessed its association with histological markers of disease severity in a large sample of NAFLD liver biopsies. METHODS Liver biopsies from a large cohort of adults who participated in two studies conducted by the NASH Clinical Research Network (NASH CRN) were included in this cross-sectional study. Liver histology was assessed centrally and various histological features scored in a systematic fashion. The relationship between microvesicular steatosis and various histological features that characterize NAFLD was tested by multiple logistic regression, after controlling for age, gender, race, body mass index, and diabetes. RESULTS Among 1022 liver biopsies included, 102 (10%) had microvesicular steatosis. No demographic differences were noted between patients with or without microvesicular steatosis. The presence of microvesicular steatosis was associated with higher grades of steatosis (p<0.001), ballooning cell injury (p<0.001), presence of Mallory-Denk bodies (p<0.007), presence of megamitochondria (p<0.0001), higher NAS scores (p<0.0001), more advanced fibrosis (p<0.0001), and diagnosis of borderline or definite NASH (p<0.0001). CONCLUSIONS Microvesicular steatosis correlates with more advanced histology of NAFLD. Longitudinal studies are needed to address the role of microvesicular steatosis in mediating cellular injury and disease progression in NAFLD.

Serum proteomics and biomarker discovery across the spectrum of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), ranging from relatively benign simple steatosis to progressive nonalcoholic steatohepatitis (NASH) and fibrosis, is an increasingly common chronic liver disease. Liver biopsy is currently the only reliable tool for staging the subtypes of NAFLD; therefore, noninvasive serum biomarkers for evaluation of liver disease and fibrosis are urgently needed. We performed this study to describe changes in the serum proteome and identify biomarker candidates in serum samples from 69 patients with varying stages of NAFLD (simple steatosis, NASH, and NASH with advanced bridging [F3/F4] fibrosis) and 16 obese controls. Using a label‐free mass spectrometry‐based approach we identified over 1,700 serum proteins with a peptide identification (ID) confidence level of >75%, 605 of which changed significantly between any two patient groups (false discovery rate <5%). Importantly, expression levels of 55 and 15 proteins changed significantly between the simple steatosis and NASH F3/F4 group and the NASH and NASH F3/F4 group, respectively. Classification of proteins with significant changes showed involvement in immune system regulation and inflammation, coagulation, cellular and extracellular matrix structure and function, and roles as carrier proteins in the blood. Further, many of these proteins are synthesized exclusively by the liver and could potentially serve as diagnostic biomarkers for identifying and staging NAFLD. Conclusion: This proteomic analysis reveals important information regarding the pathogenesis/progression of NAFLD and NASH and demonstrates key changes in serum protein expression levels between control subjects and patients with different stages of fatty liver. Future validation of these potential biomarkers is needed such that these proteins may be used in place of liver biopsy to facilitate diagnosis and treatment of patients with NAFLD. (HEPATOLOGY 2009.)

Is adiponectin involved in the pathogenesis of nonalcoholic steatohepatitis? A preliminary human study

Background: Animal studies have suggested that adiponectin may play a role in the pathogenesis of alcoholic and nonalcoholic fatty liver disease. Studies are limited that evaluated the role of adiponectin in the pathogenesis of nonalcoholic steatohepatitis (NASH). Methods: To further our understanding of the role of adiponectin in the pathogenesis of NASH, the following studies were conducted. Serum adiponectin was measured and correlated with anthropometric and nutritional variables in 21 patients with biopsy-proven NASH and 19 age-, gender-, body mass index-, and body fat-matched controls. The effect of a mixed meal on serum adiponectin levels in a subgroup of patients (n = 24) with NASH and controls was assessed. In a separate cohort, liver samples belonging to healthy (n = 11), steatotic (n = 12), and NASH (n = 12) patients were used to further explore the role of adiponectin by measuring the expression of adiponectin and adiponectin receptor (AdipoR2) mRNA. Results: Patients with NASH had significantly lower levels of serum adiponectin than controls (4.9 ± 2.7 vs. 7.3 ± 3.5 μg/mL, P = 0.02). While no significant correlation existed between serum adiponectin and anthropometric or nutritional variables, it was independently associated with age, high density lipoprotein, and triglycerides. Mixed meal had no effect on serum adiponectin either in patients with NASH or in controls. There was no expression of adiponectin mRNA in any of liver samples studied. However, AdipoR2 mRNA expression was higher in NASH than in steatotic and normal liver tissue. Conclusion: These data show that adiponectin may have a role in the pathogenesis of human NASH and should be investigated further.