8 research outputs found
HLA-DPA1*02:01~B1*01:01 is a risk haplotype for primary sclerosing cholangitis mediating activation of NKp44+ NK cells
Objective Primary sclerosing cholangitis (PSC) is characterised by bile duct strictures and progressive liver disease, eventually requiring liver transplantation. Although the pathogenesis of PSC remains incompletely understood, strong associations with HLA-class II haplotypes have been described. As specific HLA-DP molecules can bind the activating NK-cell receptor NKp44, we investigated the role of HLA-DP/NKp44-interactions in PSC. Design Liver tissue, intrahepatic and peripheral blood lymphocytes of individuals with PSC and control individuals were characterised using flow cytometry, immunohistochemical and immunofluorescence analyses. HLA-DPA1 and HLA-DPB1 imputation and association analyses were performed in 3408 individuals with PSC and 34 213 controls. NK cell activation on NKp44/HLA-DP interactions was assessed in vitro using plate-bound HLA-DP molecules and HLA-DPB wildtype versus knock-out human cholangiocyte organoids. Results NKp44+NK cells were enriched in livers, and intrahepatic bile ducts of individuals with PSC showed higher expression of HLA-DP. HLA-DP haplotype analysis revealed a highly elevated PSC risk for HLA-DPA1*02:01~B1*01:01 (OR 1.99, p=6.7×10-50). Primary NKp44+NK cells exhibited significantly higher degranulation in response to plate-bound HLA-DPA1*02:01-DPB1*01:01 compared with control HLA-DP molecules, which were inhibited by anti-NKp44-blocking. Human cholangiocyte organoids expressing HLA-DPA1*02:01-DPB1*01:01 after IFN-γ-exposure demonstrated significantly increased binding to NKp44-Fc constructs compared with unstimulated controls. Importantly, HLA-DPA1*02:01-DPB1*01:01-expressing organoids increased degranulation of NKp44+NK cells compared with HLA-DPB1-KO organoids. Conclusion Our studies identify a novel PSC risk haplotype HLA-DP A1*02:01~DPB1*01:01 and provide clinical and functional data implicating NKp44+NK cells that recognise HLA-DPA1*02:01-DPB1*01:01 expressed on cholangiocytes in PSC pathogenesis
Frequent detection of functional hyposplenism via assessment of pitted erythrocytes in patients with advanced liver cirrhosis
Background Asplenia or functional hyposplenism are risk factors for severe infections, and vaccinations against encapsulated bacteria are advised. There are only limited data regarding the spleen function of cirrhotic patients. Methods We evaluated spleen function in patients with liver cirrhosis, who were prospectively enrolled in this study. Spleen function was evaluated by the measurement of pitted erythrocytes. Functional hyposplenism was defined as a percentage of PE of >15%. Results 117 patients, mean age 58.4 years and 61.5% (n = 72) male with liver cirrhosis were included. Functional hyposplenism was diagnosed in 28/117 patients (23.9%). Pitted erythrocytes correlated with albumin (p = 0.024), bilirubin (pConclusion A quarter of patients with liver cirrhosis and almost 50% of patients with Child C cirrhosis have functional hyposplenism. Functional hyposplenism is associated with poor liver function and the degree of portal hypertension, which is characterized by higher liver stiffness measurements in transient elastography
Performance of non-invasive fibrosis scores in non-alcoholic fatty liver disease with and without morbid obesity
Background!#!Non-invasive scores, such as the non-alcoholic fatty liver disease (NAFLD) Fibrosis Score (NFS), are increasingly used for liver fibrosis assessment in patients with NAFLD. The aim of this study was to assess the applicability and reliability of non-invasive fibrosis scores in NAFLD patients with and without morbid obesity.!##!Methods!#!Three hundred sixty-eight patients with biopsy-proven NAFLD identified between January 2012 and December 2015 were studied; 225 with morbid obesity (biopsy obtained during bariatric surgery) and 143 patients without (termed as 'conventional').!##!Results!#!Median age was 47 years, 57% were female. Median body mass index (BMI) was 42.9 kg/m!##!Conclusions!#!Our data suggest that FIB-4 score is an accurate predictor of advanced fibrosis in NAFLD throughout all BMI stages. Without adjustment, NFS tends to overestimate fibrosis in morbidly obese NAFLD patients. This problem may be solved by implementation of an upper BMI limit (for NFS) or adjustment of diagnostic thresholds
The impact of individual patient data in a network meta-analysis: an investigation into parameter estimation and model selection
The use of individual patient data (IPD) in network meta-analysis (NMA) is
becoming increasingly popular. However, as most studies do not report IPD,
most NMAs are performed using aggregate data for at least some, if not all, of
the studies. We investigate the benefits of including varying proportions of IPD
studies in an NMA.
Several models have previously been developed for including both aggregate
data and IPD in the same NMA.We performed a simulation study based on these
models to examine the impact of additional IPD studies on the accuracy and
precision of the estimates of both the treatment effect and the covariate effect.
We also compared the deviance information criterion (DIC) between models to
assess model fit. An increased proportion of IPD resulted in more accurate and
precise estimates for most models and datasets. However, the coverage probability
sometimes decreased when the model was misspecified. The use of IPD leads
to greater differences in DIC, which allows us choose the correct model more
often.
We analysed a Hepatitis C network consisting of 3 IPD observational studies.
The ranking of treatments remained the same for all models and datasets. We
observed similar results to the simulation study: The use of IPD leads to differences
in DIC and more precise estimates for the covariate effect. However, IPD
sometimes increased the posterior SD of the treatment effect estimate, which
may indicate between study heterogeneity. We recommend that IPD should be
used where possible, especially for assessing model fit
Factors associated with long-term survival after liver transplantation: A retrospective cohort study
Risk factors associated with bleeding after prophylactic endoscopic variceal ligation in cirrhosis
Background Prophylactic endoscopic variceal band ligation (EVL) is frequently performed in patients with liver cirrhosis. The aim of our study was to identify factors associated with early upper gastrointestinal bleeding (UGIB) in cirrhosis patients after prophylactic EVL. Methods 787 nonemergency EVLs performed in 444 patients in two German University medical centers were analyzed retrospectively. Results Within 30 days after EVL, 38 UGIBs were observed (4.8% of all procedures). Bilirubin levels (hazard ratio [HR] 1.5, 95% confidence interval [CI] 1.2-2.0 for a 2-fold increase) and presence of varices grade III/IV according to Paquet (HR 2.6, 95%CI 1.3-5.0 compared with absence or smaller sized varices) were independently associated with UGIB following EVL. International normalized ratio (INR) was associated with bleeding events in the univariate analysis but did not reach statistical significance after adjustment for bilirubin and presence of varices grade III/IV (HR 1.2, 95 %CI 0.9-1.6 for an increase by 0.25). There was no statistically significant association between platelet count or fibrinogen levels and UGIB. Substitution of coagulation products did not affect incidence of bleeding after EVL, which also applied to patients with coagulopathy (INR > 1.5 and/or platelet count < 50 x 10(9)/L). No association between proton pump inhibitor therapy and post-EVL UGIB was observed. Conclusions EVL is a safe procedure and immediate bleeding complications are rare. Serum bilirubin levels and size of varices, rather than coagulation indices, are associated with UGIB after EVL. Our data do not support the preventive substitution of blood or coagulation products
Treatment and re-treatment results of HCV patients in the DAA era.
BACKGROUND:Re-treatment in patients with a chronic hepatitis C virus (HCV) infection and a previous failure to direct-acting antiviral (DAA) treatment remains a challenge. Therefore, we investigated the success rate of treatment and re-treatment regimens used at our center from October 2011 to March 2018. METHODS:A retrospective analysis of DAA-based HCV therapies of 1096 patients was conducted. Factors associated with a virological relapse were identified by univariable and multivariable logistic regression, treatment success of the re-treatment regimens was evaluated by an analysis of sustained virological response (SVR) rates in patients with a documented follow-up 12 weeks after the end of treatment. RESULTS:Of 1096 patients treated with DAA-based regimens, 91 patients (8%) were lost to follow-up, 892 of the remaining 1005 patients (89%) achieved an SVR12. Most patients (65/113, 58%) who experienced a virological relapse received an interferon-based DAA regimen. SVR rates were comparable in special cohorts like liver transplant recipients (53/61, 87%) and people with a human immunodeficiency virus (HIV) coinfection (41/45, 91%). On multivariable analysis, interferon-based DAA therapy was associated with treatment failure (odds ratio 0.111, 95%-confidence interval 0.054-0.218) among others. One hundred seventeen patients with multiple DAA treatment courses were identified, of which 97 patients (83%) experienced a single relapse, but further relapses after two (18/117, 15%) or even three (2/117, 2%) treatment courses were also observed. Eighty-two of 96 (85%) re-treatment attempts with all-oral DAA regimens were successful after an initial treatment failure. CONCLUSION:Overall, DAA re-treatments were highly effective in this real-world cohort and only a minority of patients failed more than two treatment courses. Switching to-or addition of-a new drug class seem to be valid options for the re-treatment of patients especially after failure of an interferon-based regimen