Immunoglobulin subclass 4 for the diagnosis of immunoglobulin subclass 4-associated diseases in an unselected liver and pancreas clinic population

AbstractAimsThe diagnosis of autoimmune pancreatitis (AIP) and immunoglobulin subclass 4 (IgG4)-associated cholangitis (IAC) is based on imaging studies, serology, histology and a response to steroid therapy. The major serological finding is an elevation of the serum IgG4 concentration. Previous studies have shown that its sensitivity is about 70% and its specificity exceeds 90% at a cut-off of 140mg/dl in selected patient populations. The aim of the present study was to assess the performance of serum IgG4 as a diagnostic parameter in an unselected liver and pancreas clinic population.Methods and resultsIgG4 was prospectively determined in 1412 patients and clinical diagnoses were recorded from a review of patient charts. The prevalence of AIP or IAC in the entire cohort was 1.1% (n= 15). The sensitivity of IgG4 for the diagnosis of AIP and IAC was 80% and the specificity was 86% at a cut-off value of ≥135mg/dl. The positive predictive value and the negative predictive value were 6% and 99.7%, respectively. The most common differential diagnosis in patients with elevated IgG4 was liver cirrhosis.ConclusionIgG4 has a reasonable sensitivity and specificity in a liver and pancreas clinic population, where liver cirrhosis appears to be the most frequent differential diagnosis for elevated IgG4 concentrations

Reassessment of Relevance and Predictive Value of Parameters Indicating Early Graft Dysfunction in Liver Transplantation: AST Is a Weak, but Bilirubin and INR Strong Predictors of Mortality

Introduction: Early graft dysfunction (EAD) complicates liver transplantation (LT). The aim of this analysis was to discriminate between the weight of each variable as for its predictive value toward patient and graft survival. Methods: We reviewed all LT performed at the Medical University of Innsbruck between 2007 and 2018. EAD was recorded when one of the following criteria was present: (i) aspartate aminotransferase (AST) levels >2,000 IU/L within the first 7 days, (ii) bilirubin levels 10mg/dL or (iii) international normalized ratio (INR) 1.6 on postoperative day 7. Results: Of 616 LT, 30.7% developed EAD. Patient survival did not differ significantly (P = 0.092; log rank-test = 2.87), graft survival was significantly higher in non-EAD patients (P = 0.008; log rank-test = 7.13). Bilirubin and INR on postoperative day 7 were identified as strong mortality predictors (Bilirubin HR = 1.71 [1.34, 2.16]; INR HR = 2.69 [0.51, 14.31]), in contrast to AST (HR = 0.91 [0.75, 1.10]). Similar results were achieved for graft loss estimation. A comparison with the Model for Early Allograft Function (MEAF) and the Liver Graft Assessment Following Transplantation (L-GrAFT) score identified a superior discrimination potential but lower specificity. Conclusion: Contrarily to AST, bilirubin and INR have strong predictive capacity for patient and graft survival. This fits well with the understanding, that bile duct injury and deprivation of synthetic function rather than hepatocyte injury are key factors in LT

Proposal for the Quantum Simulation of the \mathbb CP(2) Model on Optical Lattices

The 2d CP(N 1) models share a number of features with QCD, like asymptotic freedom, a dynamically generated mass gap and topological sectors. They have been formulated and analysed successfully in the framework of the so-called D-theory, which provides a smooth access to the continuum limit. In that framework, we propose an experimental set-up for the quantum simulation of the CP(2) model. It is based on ultra-cold Alkaline-Earth Atoms (AEAs) located on the sites of an optical lattice, where the nuclear spins represent the relevant degrees of freedom. We present numerical results for the correlation length and for the real time decay of a false vacuum, to be compared with such a future experiment. The latter could also enable the exploration of q-vacua and of the phase diagram at finite chemical potentials, since it does not suffer from any sign problem