Kamath, Patrick S.

Chronic passive hepatic congestion (congestive hepatopathy) leads to hepatic fibrosis; however, the mechanisms involved in this process are not well understood. We developed a murine experimental model of congestive hepatopathy through partial ligation of the inferior vena cava (pIVCL). C57BL/6 and transgenic mice overexpressing tissue factor pathway inhibitor (SM22α‐TFPI) were subjected to pIVCL or sham. Liver and blood samples were collected and analyzed in immunohistochemical, morphometric, real‐time polymerase chain reaction, and western blot assays. Hepatic fibrosis and portal pressure were significantly increased after pIVCL concurrent with hepatic stellate cell (HSC) activation. Liver stiffness, as assessed by magnetic resonance elastography, correlated with portal pressure and preceded fibrosis in our model. Hepatic sinusoidal thrombosis as evidenced by fibrin deposition was demonstrated both in mice after pIVCL as well as in humans with congestive hepatopathy. Warfarin treatment and TFPI overexpression both had a protective effect on fibrosis development and HSC activation after pIVCL. In vitro studies show that congestion stimulates HSC fibronectin (FN) fibril assembly through direct effects of thrombi as well as by virtue of mechanical strain. Pretreatment with either Mab13 or Cytochalasin‐D, to inhibit β‐integrin or actin polymerization, respectively, significantly reduced fibrin and stretch‐induced FN fibril assembly. Conclusion : Chronic hepatic congestion leads to sinusoidal thrombosis and strain, which in turn promote hepatic fibrosis. These studies mechanistically link congestive hepatopathy to hepatic fibrosis. (H epatology 2015;61:648‐659)

SummaryBackgroundIt remains unclear whether a long‐acting preparation of octreotide (Sandostatin LAR) can be safely used for portal hypertension in patients with compensated cirrhosis.AimTo determine the safety and efficacy of LAR among patients with Child Pugh Class A or B cirrhosis and small oesophageal varices.MethodsA randomised, double‐blind, placebo‐controlled study was conducted in 39 patients with cirrhosis and small oesophageal varices. Safety was based on frequency and severity of adverse events. Efficacy was determined by hepatic vein pressure gradient (HVPG) measured at baseline and day 84 following administration of LAR 10 mg (n = 15), 30 mg (n = 10) or saline (n = 14). Fasting and postprandial portal blood flow (PBF), superior mesenteric artery pulsatility index (SMA‐PI), glucagon and octreotide levels were measured. An intention‐to‐treat analysis was performed.ResultsFour patients in the LAR 30 group (40%) withdrew from the study due to serious adverse events. No patient in the LAR 10 or control group had serious adverse events. There was no statistically significant decrease between HVPG at day 84 and baseline with LAR 30 mg (11.8 ± 2.3 mmHg vs. 14.1 ± 3.2), LAR 10 mg (15.3 ± 4.8 mmHg vs. 15.1 ± 3.8), or saline (13.3 ± 3.8 mmHg vs. 15.1 ± 4.3) (P = 0.26). Neither PBF, SMA‐PI nor plasma glucagon levels were significantly decreased from baseline (P = 0.56).ConclusionsThe absence of significant haemodynamic benefit, as well as the high frequency of severe adverse events associated with use of LAR, do not support the use of this agent in the treatment of portal hypertension.

ABSTRACT Although Helicobacter pylori is a cosmopolitan colonizer of the human stomach, the responses among persons in remote populations from whom H. pylori was cultured have not been studied. We report on studies of 189 persons in the Ladakh region of India in whom serum immunoglobulin G responses to H. pylori whole-cell and CagA antigens were measured. H. pylori was isolated from 68 of these patients. An H. pylori whole-cell antigen derived from Ladakhi strains outperformed a similar antigen from U.S. strains, as determined by antigen-specific enzyme-linked immunosorbent assays. In total, 95% of the population was seropositive, including individuals responding only to the CagA antigen. Correlation with culture results showed that these were true positives and, therefore, that the H. pylori whole-cell serology was falsely negative in some cases. In addition to establishing a collection of H. pylori isolates from a remote area in the world, we show that use of H. pylori whole-cell and CagA serology together increases the sensitivity for the detection of colonization.