Fecal Microbiome Distinguishes Alcohol Consumption From Alcoholic Hepatitis But Does Not Discriminate Disease Severity.

BACKGROUND AND AIMS: The role of the intestinal microbiome in alcoholic hepatitis is not established. The aims of this study were to (1) characterize the fecal microbial ecology associated with alcoholic hepatitis, (2) relate microbiome changes to disease severity, and (3) infer the functional relevance of shifts in microbial ecology. APPROACH AND RESULTS: The fecal microbiome in patients with moderate alcoholic hepatitis (MAH) or severe alcoholic hepatitis (SAH) was compared with healthy controls (HCs) and heavy drinking controls (HDCs). Microbial taxa were identified by 16S pyrosequencing. Functional metagenomics was performed using PICRUSt. Fecal short chain fatty acids (SCFAs) were measured using a liquid chromatography-mass spectrometry platform. A total of 78 participants (HC, n = 24; HDC, n = 20; MAH, n = 10; SAH, n = 24) were studied. HDC had a distinct signature compared with HC with depletion of Bacteroidetes (46% vs. 26%; P = 0.01). Alcoholic hepatitis was associated with a distinct microbiome signature compared with HDC (area under the curve = 0.826); differential abundance of Ruminococcaceae, Veillonellaceae, Lachnospiraceae, Porphyromonadaceae, and Rikenellaceae families were the key contributors to these differences. The beta diversity was significantly different among the groups (permutational multivariate analysis of variance [PERMANOVA] P < 0.001). SAH was associated with increased Proteobacteria (SAH 14% vs. HDC 7% and SAH vs. HC 2%, P = 0.20 and 0.01, respectively). Firmicutes abundance declined from HDC to MAH to SAH (63% vs. 53% vs. 48%, respectively; P = 0.09, HDC vs. SAH). Microbial taxa did not distinguish between MAH and SAH (PERMANOVA P = 0.785). SCFAs producing bacteria (Lachnospiraceae and Ruminococcaceae) were decreased in alcoholic hepatitis, and a similar decrease was observed in fecal SCFAs among alcoholic hepatitis patients. CONCLUSIONS: There are distinct changes in fecal microbiome associated with the development, but not severity, of alcoholic hepatitis.

Dual-photon microscopy-based quantitation of fibrosis-related parameters (q-FP) to model disease progression in steatohepatitis.

There is a need for further refinement of current histological systems for assessment of hepatic fibrosis in nonalcoholic fatty liver disease (NAFLD). This study evaluated hepatic fibrosis in NAFLD using dual-photon microscopy-based quantitation of fibrosis-related parameters (q-FPs). Fifty test cohort subjects and 42 validation cohort subjects with NAFLD and the full spectrum of fibrosis were studied. q-FPs were measured in specific predefined regions of interest (general, vessel, perisinusoid, and vascular septa). Seventy q-FPs had inter- and intraobserver concordance ≥0.8 and were related to the NASH Clinical Research Network fibrosis staging. Of these, 16 q-FPs with the strongest correlations (P < 0.001 for all) were entered in a principal component analysis model (odds ratio [OR] 7.8, P < 0.001), which separated any stage of fibrosis versus no fibrosis, and cirrhosis versus earlier stages with the areas under the receiver operating characteristic curves of 0.88 and 0.93 (P ≤ 0.01 for both), respectively. In an independent multivariable analysis, four q-FPs-the number of collagen strands (OR 8.5, P = 0.004), strand length (OR 12.0, P = 0.02), strand eccentricity (OR 8.3, P = 0.004), and strand solidity (OR 8.0, P = 0.003)-were independently associated with fibrosis stages and were used to model fibrosis along a continuous linear scale using desirability functions; this linear scale of fibrosis measurement was also related to fibrosis stage (P < 0.0001). The robustness of both the multivariable model and the linear scale of measurement was confirmed in the validation cohort. CONCLUSION: The q-FP model provides an accurate reproducible method to evaluate fibrosis in NAFLD along a quantitative and continuous scale. (Hepatology 2017;65:1891-1903).