Pediatric metabolic-associated fatty liver disease (MAFLD) is a global health problem, with lifestyle modification as its major therapeutic strategy. Rigorous characterization of dietary content on MAFLD in children is lacking. We hypothesized an objectively measured healthier diet would positively modulate MAFLD. Diet was assessed using the Nutrition Data System for Research in children enrolled from 10 tertiary clinical centers to determine the Healthy Eating Index (HEI, 0-100) and individual food components. In all, 119 children were included (13.3 ± 2.7y), 80 (67%) male, 67 (18%) White, and 90 (76%) Hispanic, with an average body mass index Z-score of 2.2 ± 0.5. Diet was classified as low HEI < 47.94 (n = 39), mid HEI ≥ 47.94 and < 58.89 (n = 41), or high HEI ≥ 58.89 (n=39). Children with high HEI (healthier diet) had lower body weight (p = 0.005) and more favorable lipids. Mean serum triglycerides for low, mid, and high HEI were 163, 148, and 120mg/dL, respectively; p = 0.04 mid versus high, p = 0.01 low versus high. Mean HDL was 38, 41 and 43mg/dL; p = 0.02 low vs high. Less severe steatosis was noted with added sugar ≤ 10% of calories (p = 0.03). Higher lobular inflammation is associated with a higher percentage of calories from fat (OR (95% CI) = 0.95 (0.91-1.00), p = 0.04). In children with MAFLD, high HEI is associated with lower body weight and more favorable lipids, while added sugar and fat intake has individual histologic features. Differential consumption of major dietary components may modify both metabolic risk factors and histologic liver injury, highlighting the importance of objective diet assessments in children with MAFLD.

Non-alcoholic steatohepatitis (NASH) prevalence is increasing worldwide, causing a significant medical burden, but no approved therapeutics are currently available. NASH drug development requires histological analysis of liver biopsies by expert pathologists for trial enrollment and efficacy assessment, which can be hindered by multiple issues including sample heterogeneity, inter-reader and intra-reader variability, and ordinal scoring systems. Consequently, there is a high unmet need for accurate, reproducible, quantitative, and automated methods to assist pathologists with histological analysis to improve the precision around treatment and efficacy assessment. Digital pathology (DP) workflows in combination with artificial intelligence (AI) have been established in other areas of medicine and are being actively investigated in NASH to assist pathologists in the evaluation and scoring of NASH histology. DP/AI models can be used to automatically detect, localize, quantify, and score histological parameters and have the potential to reduce the impact of scoring variability in NASH clinical trials. This narrative review provides an overview of DP/AI tools in development for NASH, highlights key regulatory considerations, and discusses how these advances may impact the future of NASH clinical management and drug development. This should be a high priority in the NASH field, particularly to improve the development of safe and effective therapeutics.

There are limited prospective data on patients with type 2 diabetes mellitus (T2DM) specifically enrolled and systematically assessed for advanced fibrosis or cirrhosis due to non-alcoholic fatty liver disease (NAFLD). Therefore, we aimed to evaluate the prevalence of advanced fibrosis and cirrhosis in a prospectively recruited cohort of adults with T2DM. This prospective study enrolled adults aged ≥50 years with T2DM, recruited from primary care or endocrinology clinics. Participants underwent a standardized clinical research visit with MRI-proton density fat fraction (MRI-PDFF), magnetic resonance elastography (MRE), vibration-controlled transient elastography (VCTE) and controlled-attenuation parameter. NAFLD was defined as MRI-PDFF ≥5% after exclusion of other liver diseases. Advanced fibrosis and cirrhosis were defined by established liver stiffness cut-off points on MRE or VCTE if MRE was not available. Of 524 patients screened, 501 adults (63% female) with T2DM met eligibility. The mean age and BMI were 64.6 (±8.1) years and 31.4 (±5.9) kg/m2, respectively. The prevalence of NAFLD, advanced fibrosis and cirrhosis was 65%, 14% and 6%, respectively. In multivariable adjusted models, adjusted for age and sex, obesity and insulin use were associated with increased odds of advanced fibrosis (odds ratio 2.50; 95% CI 1.38-4.54; p= 0.003 and odds ratio 2.71; 95% CI 1.33-5.50; p= 0.006, respectively). Among 29 patients with cirrhosis, two were found to have hepatocellular carcinoma and one patient had gallbladder adenocarcinoma. Utilizing a uniquely well-phenotyped prospective cohort of patients aged ≥50 years with T2DM, we found that the prevalence of advanced fibrosis was 14% and that of cirrhosis was 6%. These data underscore the high risk of advanced fibrosis/cirrhosis in adults aged ≥50 years with T2DM. Non-alcoholic fatty liver disease (NAFLD) is common in patients with type 2 diabetes (T2DM), however, there are limited prospective data characterizing the prevalence of advanced fibrosis and cirrhosis using the most accurate non-invasive biomarkers of liver fat and fibrosis. We show that 14% of older adults with T2DM have advanced fibrosis and 6% have cirrhosis, which places them at risk for liver failure and liver cancer. Accurate prevalence rates and comparative analysis regarding the diagnostic accuracy of non-invasive tests in this population will guide the optimal screening strategy and future cost-effectiveness analyses. These results will inform future Hepatology and Endocrinology practice guidelines regarding NAFLD screening programs in older adults with T2DM.

The NASH Clinical Research Network histologic scoring system, the gold-standard NASH histology assessment for clinical trials, has demonstrated intrarater and interrater variability. An expert panel in a previous systematic Research and Development/University of California Los Angeles (RAND/UCLA) study determined that existing histologic scoring systems do not fully capture NASH disease activity and fibrosis, and standardized definitions of histologic features are needed. We evaluated the reliability of existing and alternate histologic measures and their correlations with a disease activity visual analog scale to propose optimal components for an expanded NAFLD activity score (NAS). Four liver pathologists who were involved in the prior RAND/UCLA study underwent standardized training and multiple discussions with the goal of improving agreement. They were blinded to clinical information and scored histologic measures twice, ≥2 weeks apart, for 40 liver biopsies representing the full spectrum of NAFLD. Index intraclass correlation coefficient (ICC) estimates demonstrated intrarater (0.80-0.85) and interrater (0.60-0.72) reliability. Hepatocyte ballooning items had similar interrater ICCs (0.68-0.79), including those extending scores from 0-2 to 0-4. Steatosis measures (interrater ICCs, 0.72-0.80) correlated poorly with disease activity. Correlations with disease activity were largest for hepatocyte ballooning and Mallory-Denk bodies (MDBs), with both used to develop the expanded NAS (intrarater ICC, 0.90; interrater ICC, 0.80). Fibrosis measures had ICCs of 0.70-0.87. After extensive preparation among a group of experienced pathologists, we demonstrated improved reliability of multiple existing histologic NAFLD indices and fibrosis staging systems. Hepatocyte ballooning and MDBs most strongly correlated with disease activity and were used for the expanded NAS. Further validation including evaluation of responsiveness is required.

Background/AimsGlycogen synthesis and storage are normal hepatocyte functions. However, glycogenosis, defined as excess hepatocyte glycogen visible by routine H&E light microscopy, has not been well characterized in nonalcoholic fatty liver disease (NAFLD).MethodsGlycogenosis in NAFLD liver biopsies was graded as “none”, “focal” (in <50% of hepatocytes), or “diffuse” (in ≥50% of hepatocytes). Clinical and pathological variables associated with glycogenosis were assessed. 2047 liver biopsies were prospectively analysed.ResultsIn adults and children, any glycogenosis was present in 54% of cases; diffuse glycogenosis was noted in approximately 1/3 of cases. On multiple logistic regression analysis, adults with glycogenosis tended to be older (P = .003), female (P = .04), have higher serum glucose (P = .01), and use insulin (P = .02). Adults tended to have lower steatosis scores (P = .006) and lower fibrosis stages (P = .005); however, unexpectedly, they also tended to have more hepatocyte injury including ballooning (P = .003). On multiple logistic regression analysis, paediatric patients with glycogenosis were more likely to be Hispanic (P = .03), have lower body weight (P = .002), elevated triglycerides (P = .001), and a higher fasting glucose (P = .007). Paediatric patients with glycogenosis also had less steatosis (P < .001) than those without.ConclusionsGlycogenosis is common in adult and paediatric NAFLD, and is associated with clinical features of insulin resistance. Glycogenosis is important to recognize histologically because it may be misinterpreted as ballooning, and when diffuse, confusion with glycogen storage disorders or glycogenic hepatopathy must be avoided. The newly observed dichotomous relationship between glycogenosis and increased liver cell injury but decreased steatosis and fibrosis requires further study.

Among 1,770 healthcare workers serving in high-risk care areas for coronavirus disease 2019 (COVID-19), 39 (2.2%) were seropositive. Exposure to severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in the community was associated with being seropositive. Job or unit type and percentage of time working with COVID-19 patients were not associated with positive antibody tests.

Background: Previous studies have demonstrated the noninferiority of pathologists’ interpretation of whole slide images (WSIs) compared to microscopic slides in diagnostic surgical pathology; however, to our knowledge, no published studies have tested analytical precision of an entire WSI system. Methods: In this study, five pathologists at three locations tested intra-system, inter-system/site, and intra- and inter-pathologist precision of the Aperio AT2 DX System (Leica Biosystems, Vista, CA, USA). Sixty-nine microscopic slides containing 23 different morphologic features suggested by the Digital Pathology Association as important to diagnostic pathology were identified and scanned. Each of 202 unique fields of view (FOVs) had 1-3 defined morphologic features, and each feature was represented in three different tissues. For intra-system precision, each site scanned 23 slides at three different times and one pathologist interpreted all FOVs. For inter-system/site precision, all 69 slides were scanned once at each of three sites, and FOVs from each site were read by one pathologist. To test intra- and inter-pathologist precision, all 69 slides were scanned at one site, FOVs were saved in three different orientations, and the FOVs were transferred to a different site. Three different pathologists then interpreted FOVs from all 69 slides. Wildcard (unscored) slides and washout intervals were included in each study. Agreement estimates with 95% confidence intervals were calculated. Results: Combined precision from all three studies, representing 606 FOVs in each of the three studies, showed overall intra-system agreement of 97.9%; inter-system/site agreement was 96%, intra-pathologist agreement was 95%, and inter-pathologist agreement was 94.2%. Conclusions: Pathologists using the Aperio AT2 DX System identified histopathological features with high precision, providing increased confidence in using WSI for primary diagnosis in surgical pathology.

Polyomavirus nephropathy (PVN) is a major complication of kidney transplantation. Most reports describe polyomavirus viremia either precedes or is detectable at the time of diagnosis of PVN. This association is the basis of current screening recommendations. We retrospectively reviewed the PCR results of blood and urine samples from 29 kidney transplant recipients with biopsy-proven PVN. Biopsies were performed for a rise in serum creatinine or persistent high-level BK viruria. All biopsies showed polyoma virus large T-antigen expression in tubular epithelium using immunohistochemistry. All had viruria preceding or at the time of biopsy (range, 5.2 × 104 to >25 × 106 BKV DNA copies/ml). Twenty (69%) had viremia ranging from 2.5 × 103 to 4.3 × 106 copies/ml at the time of the biopsy. Via blood BK PCR assay, nine (31%) had no BK viremia detected either preceding or at the time of the biopsy. In five recipients where sufficient specimen permitted, additional plasma BK assessment revealed positive detection of viremia. A comparative analysis of assays from two centres was performed with spiked samples. BK DNA may not be detected in the blood of some kidney transplant recipients with histologically confirmed PVN. This may reflect limitation of whole blood as opposed to plasma-based BK DNA assessment.

ObjectiveHistopathology is potentially an important outcome measure in UC. Multiple histological disease activity (HA) indices, including the Geboes score (GS) and modified Riley score (MRS), have been developed; however, the operating properties of these instruments are not clearly defined. We assessed the reproducibility of existing measures of HA.DesignFive experienced pathologists with GI pathology fellowship training and expertise in IBD evaluated, on three separate occasions at least two weeks apart, 49 UC colon biopsies and scored the GS, MRS and a global rating of histological severity using a 100 mm visual analogue scale (VAS). The reproducibility of each grading system and for individual instrument items was quantified by estimates of intraclass correlation coefficients (ICCs) based on two-way random effects models. Uncertainty of estimates was quantified by 95% two-sided CIs obtained using the non-parametric cluster bootstrap method. Biopsies responsible for the greatest disagreement based on the ICC estimates were identified. A consensus process was used to determine the most common sources of measurement disagreement. Recommendations for minimising disagreement were subsequently generated.ResultsIntrarater ICCs (95% CIs) for the total GS, MRS and VAS scores were 0.82 (0.73 to 0.88), 0.71 (0.63 to 0.80) and 0.79 (0.72 to 0.85), respectively. Corresponding inter-rater ICCs were substantially lower: 0.56 (0.39 to 0.67), 0.48 (0.35 to 0.66) and 0.61 (0.47 to 0.72). Correlation between the GS and VAS was 0.62 and between the MRS and VAS was 0.61.ConclusionsAlthough ‘substantial’ to ‘almost perfect’ ICCs for intrarater agreement were found in the assessment of HA in UC, ICCs for inter-rater agreement were considerably lower. According to the consensus process results, standardisation of item definitions and modification of the existing indices is required to create an optimal UC histological instrument.

To investigate in adults the associations between histologic features of nonalcoholic fatty liver disease (NAFLD) and quantitative measures derived from diffusion-weighted imaging (DWI). Eighty-nine adults undergoing standard-of-care liver biopsy for NAFLD were recruited for DWI. Biopsies were scored for histologic features of NAFLD. DWI was performed using b-values of 0, 100, and 500 s/mm(2) . Images were reconstructed using either conventional magnitude averaging (CMA) or a method to address bulk motion artifacts (Beta*LogNormal, BLN). The apparent diffusion coefficient (ADC) and the diffusivity (D) and perfusion fraction (F) of the intravoxel incoherent motion (IVIM) model were measured in the right hepatic lobe using both reconstructions. Associations between histologic features and DWI-derived measures were tested statistically with several methods including multiple linear regression. Using CMA and BLN reconstructions, respectively, the means (and ranges) were 1.7 (1.1-3.5) and 1.4 (1.0-3.2) × 10(-3) mm(2) /s for ADC, 1.1 (0.84-1.4) and 0.84 (0.53-1.1) × 10(-3) mm(2) /s for D, and 17 and 18 (2.3-35)% for F. For both reconstruction methods, D decreased with steatosis and F decreased with fibrosis (P < 0.05). ADC was not independently associated with any histologic feature. Steatosis and fibrosis have significant independent effects on D and F in adults undergoing biopsy for NAFLD.