Dual-sugar tests of small intestinal permeability are poor predictors of bacterial infections and mortality in cirrhosis: a prospective study

AIM: To prospectively analyze the impact of increased intestinal permeability (IP) on mortality and the occurrence of infections in patients with cirrhosis.METHODS: IP was quantified using the lactulose/mannitol (L/M) test in 46 hospitalized patients with cirrhosis (25 Child-Pugh A/B, 21 Child-Pugh C) and in 16 healthy controls. Markers of inflammation [LPS-binding protein, Interleukin-6 (IL-6)] and enterocyte death [intestinal fatty-acid binding protein (I-FABP)] were determined in serum using enzyme-linked immunosorbent assays. Patients were followed for one year and assessed for survival, liver transplantation, the necessity of hospitalization and the occurrence of bacterial infections. The primary endpoint of the study was defined as differences in survival between patients with pathological and without pathological lactulose/mannitol test.RESULTS: Thirty-nine (85%) patients with cirrhosis had a pathologically increased IP index (L/M ratio > 0.07) compared to 4 (25%) healthy controls (P < 0.0001). The IP index correlated with the Child-Pugh score (r = 0.484, P = 0.001) and with serum IL-6 (r = 0.342, P = 0.02). Within one year, nineteen (41%) patients developed a total of 33 episodes of hospitalization with bacterial or fungal infections. Although patients who developed spontaneous bacterial peritonitis (SBP) (n = 7) had a higher IP index than patients who did not (0.27 vs 0.14, P = 0.018), the baseline IP index did not predict time to infection, infection-free survival or overall survival, neither when assessed as linear variable, as tertiles, nor dichotomized using an established cut-off. In contrast, model for end-stage liver disease score, Child-Pugh score, the presence of ascites, serum IL-6 and I-FABP were univariate predictors of infection-free survival.CONCLUSION: Although increased IP is a frequent phenomenon in advanced cirrhosis and may predispose to SBP, it failed to predict infection-free and overall survival in this prospective cohort study.

Intestinal Wnt in the transition from physiology to oncology

Adult stem cells are necessary for self-renewal tissues and regeneration after damage.Especially in the intestine,which self-renews every few days,they play a key role in tissue homeostasis.Therefore,complex regulatory mechanisms are needed to prevent hyperproliferation,which can lead in the worst case to carcinogenesis or under-activation of stem cells,which can result in dysfunctional epithelial.One main regulatory signaling pathway is the Wnt/β-catenin signaling pathway.It is a highly conserved pathway,withβ-catenin,a transcription factor,as target protein.Translocation ofβ-catenin from cytoplasm to nucleus activates the transcription of numerous genes involved in regulating stem cell pluripotency,proliferation,cell differentiation and regulation of cell death.This review presents a brief overview of the Wnt/β-catenin signaling pathway,the regulatory mechanism of this pathway and its role in intestinal homeostasis.Additionally,this review highlights the molecular mechanisms and the histomorphological features of Wnt hyperactivation.Furthermore,the central role of the Wnt signaling pathway in intestinal carcinogenesis as well as its clinical relevance in colorectal carcinoma are discussed.