Acute gastrointestinal bleeding - a new approach to clinical and endoscopic management.

Overt or occult gastrointestinal bleeding is a frequently observed condition in routine gastroenterological practice. Occult gastrointestinal bleeding is usually a purely incidental finding, based on the discovery of iron deficiency anemia in the laboratory or blood in stool (a positive Hemoccult test). However, overt bleeding accompanied by the clinical features of tarry stool, hematemesis, or hematochezia may be a life-threatening condition, calling for immediate emergency management. In contrast to traumatology, algorithms of emergency and intensive medicine are not sufficiently validated yet for acute life-threatening bleeding. The purpose of this review was to present all established and new endoscopic hemostasis techniques and to evaluate their efficacy, as well as to provide the treating endoscopist with practical advice on how he/she could incorporate these procedures into acute medical management. The recommendations are based on inspection of the study results in the recent published literature, as well as emergency medicine algorithms in traumatology.

Hepcidin is an antibacterial, stress-inducible peptide of the biliary system.

BACKGROUND/AIMS: Hepcidin (gene name HAMP), an IL-6-inducible acute phase peptide with antimicrobial properties, is the key negative regulator of iron metabolism. Liver is the primary source of HAMP synthesis, but it is also produced by other tissues such as kidney or heart and is found in body fluids such as urine or cerebrospinal fluid. While the role of hepcidin in biliary system is unknown, a recent study demonstrated that conditional gp130-knockout mice display diminished hepcidin levels and increased rate of biliary infections. METHODS: Expression and localization of HAMP in biliary system was analyzed by real time RT-PCR, in-situ hybridization, immunostaining and -blotting, while prohepcidin levels in human bile were determined by ELISA. RESULTS: Hepcidin was detected in mouse/human gallbladder and bile duct epithelia. Biliary HAMP is stress-inducible, in that it is increased in biliary cell lines upon IL-6 stimulation and in gallbladder mucosa of patients with acute cholecystitis. Hepcidin is also present in the bile and elevated prohepcidin levels were observed in bile of primary sclerosing cholangitis (PSC) patients with concurrent bacterial cholangitis compared to PSC subjects without bacterial infection (median values 22.3 vs. 8.9; p = 0.03). In PSC-cholangitis subjects, bile prohepcidin levels positively correlated with C-reactive protein and bilirubin levels (r = 0.48 and r = 0.71, respectively). In vitro, hepcidin enhanced the antimicrobial capacity of human bile (p<0.05). CONCLUSION: Hepcidin is a stress-inducible peptide of the biliary epithelia and a potential marker of biliary stress. In the bile, hepcidin may serve local functions such as protection from bacterial infections.