Laura Wilson

Nonalcoholic fatty liver disease (NAFLD) activity score and the histopathologic diagnosis in NAFLD: distinct clinicopathologic meanings

The diagnosis of nonalcoholic steatohepatitis (NASH) is defined by the presence and pattern of specific histological abnormalities on liver biopsy. A separate system of scoring the features of nonalcoholic fatty liver disease (NAFLD) called the NAFLD Activity Score (NAS) was developed as a tool to measure changes in NAFLD during therapeutic trials. However, some studies have used threshold values of the NAS, specifically NAS ≥5, as a surrogate for the histologic diagnosis of NASH. To evaluate whether this unintended use of the NAS is valid, biopsy and clinical data from the 976 adults in NASH Clinical Research Network (CRN) studies were reviewed. Biopsies were evaluated centrally by the NASH CRN Pathology Committee. Definite steatohepatitis (SH) was diagnosed in 58.1%, borderline SH in 19.5% and “not SH” in 22%. The NAS was ≥5 in 50% and ≤4 in 49%; in this cohort only 75% of biopsies with definite SH had an NAS ≥5, whereas 28% of borderline SH and 7% of “not SH” biopsies had NAS ≥5. Of biopsies with an NAS ≥5, 86% had SH and 3% “not SH”. NAS ≤4 did not indicate benign histology; 29% had SH and only 42% had “not SH.” Higher values of the NAS were associated with higher levels of alanine aminotransferase and aspartate aminotransferase, whereas the diagnosis of SH was associated with features of the metabolic syndrome. Conclusion: The diagnosis of definite SH or the absence of SH based on evaluation of patterns as well as individual lesions on liver biopsies does not always correlate with threshold values of the semiquantitative NAS. Clinical trials and observational studies should take these different performance characteristics into account. (HEPATOLOGY 2011)

Serum ferritin is an independent predictor of histologic severity and advanced fibrosis in patients with nonalcoholic fatty liver disease

Serum ferritin (SF) levels are commonly elevated in patients with nonalcoholic fatty liver disease (NAFLD) because of systemic inflammation, increased iron stores, or both. The aim of this study was to examine the relationship between elevated SF and NAFLD severity. Demographic, clinical, histologic, laboratory, and anthropometric data were analyzed in 628 adult patients with NAFLD (age, ≥18 years) with biopsy‐proven NAFLD and an SF measurement within 6 months of their liver biopsy. A threshold SF >1.5 × upper limit of normal (ULN) (i.e., >300 ng/mL in women and >450 ng/mL in men) was significantly associated with male sex, elevated serum alanine aminotransferase, aspartate aminotransferase, iron, transferrin‐iron saturation, iron stain grade, and decreased platelets (P < 0.01). Histologic features of NAFLD were more severe among patients with SF >1.5 × ULN, including steatosis, fibrosis, hepatocellular ballooning, and diagnosis of NASH (P < 0.026). On multiple regression analysis, SF >1.5 × ULN was independently associated with advanced hepatic fibrosis (odds ratio [OR], 1.66; 95% confidence interval [CI], 1.05‐2.62; P = 0.028) and increased NAFLD Activity Score (NAS) (OR, 1.99; 95% CI, 1.06‐3.75; P = 0.033). Conclusions: A SF >1.5 × ULN is associated with hepatic iron deposition, a diagnosis of NASH, and worsened histologic activity and is an independent predictor of advanced hepatic fibrosis among patients with NAFLD. Furthermore, elevated SF is independently associated with higher NAS, even among patients without hepatic iron deposition. We conclude that SF is useful to identify NAFLD patients at risk for NASH and advanced fibrosis. (HEPATOLOGY 2012)

Portal chronic inflammation in nonalcoholic fatty liver disease (NAFLD): A histologic marker of advanced NAFLD—Clinicopathologic correlations from the nonalcoholic steatohepatitis clinical research network

Adult nonalcoholic fatty liver disease (NAFLD) is characterized by absent or mild portal chronic inflammation (CI); in children, portal CI may be predominant. This study correlated clinical features with portal CI. Centrally‐graded biopsies and temporally‐related clinical parameters from 728 adults and 205 children. From the Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) were evaluated. Mild, more than mild and no portal CI were found in 60%, 23% and 16% of adult biopsies and 76%, 14% and 10% of pediatric biopsies. Autoantibodies, and elevated alanine aminotransferase were not associated with portal CI. Clinical features associated with “more than mild” in adults were older age (P < 0.0001), female gender (P = 0.001), higher body mass index (P < 0.0001), elevated insulin levels (P = 0.001), higher homeostasis model assessment of insulin resistance score (HOMA‐IR) (P < 0.0001), and medications used for NAFLD (P = 0.0004), diabetes (P < 0.0001), and hypertension (P < 0.0001). “More than mild” in the pediatric biopsies correlated with younger age (P = 0.01), but not with body mass index, insulin or HOMA‐IR. In both groups, lobular and portal inflammation scores had no association, but there was an association with definite steatohepatitis (P < 0.0001). Features associated in the adult biopsies with “more than mild” were steatosis amount (P = 0.01) and location (P < 0.0001), ballooning (P < 0.0001), and advanced fibrosis (P < 0.0001). In the pediatric biopsies, “more than mild” was associated with steatosis location (P = 0.0008) and fibrosis score (P < 0.0001), specifically, the portal/periportal fibrosis or greater fibrosis) (P < 0.01). Conclusion: Increased portal CI is associated with many clinical and pathologic features of progressive NAFLD in both adults and children, but not with ALT, autoantibodies, or lobular inflammation. More than mild portal CI in liver biopsies of untreated NAFLD may be considered a marker of advanced disease. (HEPATOLOGY 2009.)

Genome-Wide Association Study Identifies Variants Associated With Histologic Features of Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS Little data are available from genome-wide association studies (GWASs) of liver histology in patients with nonalcoholic fatty liver disease (NAFLD). We conducted a pilot GWAS in patients with NAFLD, characterized by histology, who were enrolled in the NASH Clinical Research Network (CRN) Database Study. METHODS We studied clinical, laboratory, and histologic data from 236 non-Hispanic white women with NAFLD. We analyzed 324,623 single nucleotide polymorphisms (SNPs) from the 22 autosomal chromosomes. Multivariate-adjusted logistic regression analyses were conducted for binary outcomes, and linear regression analysis was applied for quantitative traits. A P value < 1 × 10(-6) was considered to be significant. RESULTS In multivariate models adjusted for age, body mass index, diabetes, waist/hip ratios, and levels of glycated hemoglobin, the NAFLD activity score was associated with the SNP rs2645424 on chromosome 8 in farnesyl diphosphate farnesyl transferase 1 (FDFT1) (P = 6.8 × 10(-7)). The degree of fibrosis was associated with the SNP rs343062 on chromosome 7 (P = 2.7 × 10(-8)). SNPs associated with lobular inflammation included SNP rs1227756 on chromosome 10 in COL13A1 (P = 2.0 × 10(-7)), rs6591182 on chromosome 11 (P = 8.6 × 10(-7)), and rs887304 on chromosome 12 in EFCAB4B (P = 7.7 × 10(-7)). SNPs associated with serum levels of alanine aminotransferase included rs2499604 on chromosome 1 (P = 2.2 × 10(-6)), rs6487679 on chromosome 12 in PZP (P = 1.3 × 10(-6)), rs1421201 on chromosome 18 (P = 1.0 × 10(-5)), and rs2710833 on chromosome 4 (P = 6.3 × 10(-7)). No significant associations were observed between genotypes and steatosis, ballooning degeneration, portal inflammation, or other features of NAFLD. CONCLUSIONS A GWAS significantly associated genetic variants with features of hepatic histology in patients with NAFLD. These findings should be validated in larger and more diverse cohorts.

Association between diabetes, family history of diabetes, and risk of nonalcoholic steatohepatitis and fibrosis.

Previous studies have shown familial aggregation of insulin resistance and nonalcoholic fatty liver disease (NAFLD). Therefore, we aimed to examine whether family history of diabetes mellitus (DM) is associated with nonalcoholic steatohepatitis (NASH) and fibrosis in patients with NAFLD. This was a cross‐sectional analysis in participants of the NAFLD Database study and PIVENS trial who had available data on family history of DM. One thousand and sixty‐nine patients (63% women), with mean age of 49.6 (± 11.8) years and body mass index (BMI) of 34.2 (± 6.4) kg/m2, were included. Thirty percent had DM, and 56% had a family history of DM. Both personal history of DM and family history of DM were significantly associated with NASH, with an odds ratio (OR) of 1.93 (95% confidence interval [CI]: 1.37‐2.73; P <0.001) and 1.48 (95% CI: 1.11‐1.97; P = 0.01) and any fibrosis with an OR of 3.31 (95% CI: 2.26‐4.85; P < 0.001) and 1.66 (95% CI: 1.25‐2.20; P < 0.001), respectively. When the models were adjusted for age, sex, BMI, ethnicity, and metabolic traits, the association between diabetes and family history of DM with NASH showed an increased adjusted OR of 1.76 (95% CI: 1.13‐2.72; P < 0.001) and 1.34 (95% CI: 0.99‐1.81; P = 0.06), respectively, and with any fibrosis with a significant adjusted OR of 2.57 (95% CI: 1.61‐4.11; P < 0.0001) and 1.38 (95% CI: 1.02‐1.87; P = 0.04), respectively. After excluding patients with personal history of diabetes, family history of DM was significantly associated with the presence of NASH and any fibrosis with an adjusted OR of 1.51 (95% CI: 1.01‐2.25; P = 0.04) and 1.49 (95% CI: 1.01‐2.20; P = 0.04), respectively. Conclusions: Diabetes is strongly associated with risk of NASH, fibrosis, and advanced fibrosis. Family history of diabetes, especially among nondiabetics, is associated with NASH and fibrosis in NAFLD. (HEPATOLOGY 2012;56:943–951)

Relationship between the pattern of hepatic iron deposition and histological severity in nonalcoholic fatty liver disease

Previous studies examining the relationship between hepatic iron deposition and histological severity in nonalcoholic fatty liver disease (NAFLD) have been inconclusive. The goal of this study was to examine the relationship between hepatic iron deposition and liver histology in 849 patients enrolled in the Nonalcoholic Steatohepatitis Clinical Research Network. Hepatic iron staining was performed in a central laboratory, and the stains were scored for grade and cellular and parenchymal localization by a central pathology committee; the relationship between the grade and pattern of iron deposition and the clinical, laboratory, and histological variables was examined with univariate and multivariate analyses. Stainable hepatic iron was present in 293 of 849 patients (34.5%) in one of three histological patterns: a hepatocellular (HC) pattern [63/849 (7.4%)], a reticuloendothelial system (RES) cell pattern [91/849 (10.7%)], or a mixed RES/HC pattern [139/849 (16.4%)]. Patients with the RES iron‐staining pattern were more likely to have advanced fibrosis compared to those with those with HC iron (P = 0.01). Patients with RES iron were also more likely to have advanced histological features such as fibrosis (P = 0.049), portal inflammation (P = 0.002), HC ballooning (P = 0.006), and definite nonalcoholic steatohepatitis (P = 0.007) compared to those with patients with HC or mixed iron patterns. The presence of RES iron (odds ratio = 1.60, 95% confidence interval = 1.10‐2.33, P = 0.015) was independently associated with advanced hepatic fibrosis on multiple regression analysis after adjustments for age, gender, diabetes status, and body mass index. Conclusion: The presence and pattern of hepatic iron deposition are associated with distinct histological features in patients with NAFLD and may have implications for pathophysiology and therapy. (HEPATOLOGY 2011;53:448‐457)

Relationship of steatosis grade and zonal location to histological features of steatohepatitis in adult patients with non-alcoholic fatty liver disease

BACKGROUND/AIMS The relationship between severity and zonal location of steatosis and the presence of steatohepatitis and various histological features that define NASH has not been formally studied. METHODS We conducted a study to examine the relationship of severity and zonal location of steatosis to the presence of NASH and to other histological features that define NASH in adult patients with NAFLD. Steatosis was graded as mild, moderate or severe. We examined the relationship between severity and zonal location of steatosis and the following: lobular inflammation, presence of ballooning, Mallory bodies, fibrosis score, and definite steatohepatitis. RESULTS Mild, moderate and severe steatosis was present in 44%, 31% and 25% of biopsies, respectively. Definite steatohepatitis was present in 59% and advanced fibrosis in 29% of liver biopsies. Increasing levels of steatosis severity were positively associated with lobular inflammation (p<0.0001), zone 3 fibrosis (p<0.001), and definite steatohepatitis (p=0.02), but were unrelated to ballooning, Mallory bodies, or advanced fibrosis. As compared to zone 3 steatosis, pan-acinar steatosis was more often associated with ballooning, Mallory bodies, and advanced fibrosis. CONCLUSIONS Patients with severe steatosis are more likely to have steatohepatitis. More studies are needed to confirm this observation and to explore its significance.

Ethnicity and Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder in the United States; however, few data are available about racial and ethnic variation. We investigated relationships between ethnicity, NAFLD severity, metabolic derangements, and sociodemographic characteristics in a well‐characterized cohort of adults with biopsy‐proven NAFLD. Data were analyzed from 1,026 adults (≥18 years) in the Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) from 2004 to 2008, for whom liver histology data were available within 6 months of enrollment. Associations between ethnicity (i.e., Latino versus non‐Latino white) and NAFLD severity (i.e., NASH versus non‐NASH histology and mild versus advanced fibrosis) were explored with multiple logistic regression analysis. We also investigated effect modification of ethnicity on metabolic derangements for NAFLD severity. Within the NASH CRN, 77% (N = 785) were non‐Latino white and 12% (N = 118) were Latino. Sixty‐one percent (N = 628) had NASH histology and 28% (N = 291) had advanced fibrosis. Latinos with NASH were younger, performed less physical activity, and had higher carbohydrate intake, compared to non‐Latino whites with NASH. Gender, diabetes, hypertension, hypertriglyceridemia, aspartate aminotransferase (AST), platelets, and the homeostasis model assessment of insulin resistance (HOMA‐IR) were significantly associated with NASH. Age, gender, AST, alanine aminotransferase, alkaline phosphatase, platelets, total cholesterol, hypertension, and HOMA‐IR, but not ethnicity, were significantly associated with advanced fibrosis. The effect of HOMA‐IR on the risk of NASH was modified by ethnicity: HOMA‐IR was not a significant risk factor for NASH among Latinos (odds ratio [OR] = 0.93; 95% confidence interval [CI]: 0.85‐1.02), but was significant among non‐Latino whites (OR, 1.06; 95% CI: 1.01‐1.11). Conclusion: Metabolic risk factors and sociodemographic characteristics associated with NASH differ by ethnicity. Additional insights into NASH pathogenesis may come from further studies focused on understanding ethnic differences in this disease. (HEPATOLOGY 2012)

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.

Mortality Risk for Patients with Cytomegalovirus Retinitis and Acquired Immune Deficiency Syndrome

We prospectively followed up 589 patients to evaluate the relationship of anti-cytomegalovirus (CMV) treatment and immune reconstitution in response to highly active antiretroviral therapy (HAART) on the mortality risk of patients with CMV retinitis and acquired immune deficiency syndrome. The use of HAART was associated with an 81% lower mortality rate (95% confidence interval [CI], 74%-86%); it was 96% lower (95% CI, 92%-98%) for those who developed immune recovery and 49% lower (95% CI, 30-63%) for those who did not. Using time-updated multivariate analysis, current systemic anti-CMV treatment was independently associated with a 28% lower mortality rate (95% CI, 8%-43%). On the basis of these results, for patients who continue to have profound immunodeficiency despite HAART, the continued use of HAART and systemic anti-CMV therapy is predicted to reduce the risk of mortality by 65%, over and above the benefits of Pneumocystis carinii and Mycobacterium avium prophylaxis.