Changes of the bacterial composition in duodenal fluid from patients with liver cirrhosis and molecular bacterascites

Small intestinal bacterial overgrowth and compositional changes of intestinal microbiota are pathomechanistic factors in liver cirrhosis leading to bacterial translocation and infectious complications. We analyzed the quantity and composition of duodenal bacterial DNA (bactDNA) in relation to bactDNA in blood and ascites of patients with liver cirrhosis. Duodenal fluid and corresponding blood and ascites samples from 103 patients with liver cirrhosis were collected. Non-liver disease patients (n = 22) served as controls. BactDNA was quantified by 16S-rRNA gene-based PCR. T-RFLP and 16S-rRNA amplicon sequencing were used to analyze bacterial composition. Duodenal bacterial diversity in cirrhosis was distinct to controls showing significantly higher abundances of Streptococcus, Enterococcus and Veillonella. Patients with bactDNA positive ascites revealed reduced spectrum of core microbiota with Streptococcus as key player of duodenal community and higher prevalence of Granulicatella proving presence of cirrhosis related intestinal dysbiosis. Regarding duodenal fluid bactDNA quantification, no significant differences were found between patients with cirrhosis and controls. Additionally, percentage of subjects with detectable bactDNA in blood did not differ between patients and controls. This study evaluated the diversity of bacterial DNA in different body specimens with potential implications on understanding how intestinal bacterial translocation may affect infectious complications in cirrhosis.

Epidemiology, clinical features and management of autoimmune hepatitis in Switzerland: a retrospective and prospective cohort study

BACKGROUND AND AIMS

The Swiss Autoimmune Hepatitis Cohort Study is a nationwide registry, initiated in 2017, that collects retrospective and prospective clinical data and biological samples from patients of all ages with autoimmune hepatitis treated at Swiss hepatology centres. Here, we report the analysis of the first 5 years of registry data.

RESULTS

A total of 291 patients with autoimmune hepatitis have been enrolled, 30 of whom were diagnosed before 18 years of age and composed the paediatric cohort. Paediatric cohort: median age at diagnosis 12.5 years (range 1-17, interquartile range (IQR) 8-15), 16 (53%) girls, 6 (32%) with type 2 autoimmune hepatitis, 8 (27%) with autoimmune sclerosing cholangitis, 1 with primary biliary cholangitis variant syndrome, 4 (15%) with inflammatory bowel disease and 10 (41%) with advanced liver fibrosis at diagnosis. Adult cohort: median age at diagnosis 54 years (range 42-64, IQR 18-81), 185 (71%) women, 51 (20%) with primary biliary cholangitis variant syndrome, 22 (8%) with primary sclerosing cholangitis variant syndrome, 9 (4%) with inflammatory bowel disease and 66 (32%) with advanced liver fibrosis at diagnosis. The median follow-up time for the entire cohort was 5.2 years (IQR 3-9.3 years). Treatment in children: 29 (97%) children were initially treated with corticosteroids, 28 of whom received combination treatment with azathioprine. Budesonide was used in four children, all in combination with azathioprine. Mycophenolate mofetil was used in five children, all of whom had previously received corticosteroids and thiopurine. Treatment in adults (data available for 228 patients): 219 (96%) were treated with corticosteroids, mostly in combination with azathioprine. Predniso(lo)ne was the corticosteroid used in three-quarters of patients; the other patients received budesonide. A total of 78 (33%) patients received mycophenolate mofetil, 62 of whom had previously been treated with azathioprine. Complete biochemical response was achieved in 13 of 19 (68%) children and 137 of 182 (75%) adults with available follow-up data. All children were alive at the last follow-up, and none had undergone liver transplantation. Five (2%) adults underwent liver transplantation, two of whom had a fulminant presentation. Four (2%) adults with autoimmune hepatitis died (two from liver-associated causes).

CONCLUSION

Patients with autoimmune hepatitis in Switzerland had clinical features similar to those in other cohorts. The proportion of patients diagnosed with primary biliary cholangitis variant syndrome was higher than expected. Autoimmune hepatitis was managed according to guidelines, except for the use of budesonide in a small proportion of paediatric patients. The outcomes were excellent, but the findings must be confirmed over a longer follow-up period.

Glucocorticoid withdrawal and glucocorticoid-induced adrenal insufficiency: Study protocol of the randomized controlled «TOASST" (Taper Or Abrupt Steroid STop) multicenter trial

BACKGROUND

Despite the widespread use of glucocorticoids in inflammatory and autoimmune disorders, there is uncertainty about the safe cessation of long-term systemic treatment, as data from prospective trials are largely missing. Due to potential disease relapse or glucocorticoid-induced hypocortisolism, the drug is often tapered to sub-physiological doses rather than stopped when the underlying disease is clinically stable, increasing the cumulative drug exposure. Conversely, the duration of exposure to glucocorticoids should be minimized to lower the risk of side effects.

METHODS

We designed a multicenter, randomized, triple-blinded, placebo-controlled trial to test the clinical noninferiority of abrupt glucocorticoid stop compared to tapering after ≥28 treatment days with ≥420 mg cumulative and ≥7.5 mg mean daily prednisone-equivalent dose. 573 adult patients treated systemically for various disorders will be included after their underlying disease has been stabilized. Prednisone in tapering doses or matching placebo is administered over 4 weeks. A 250 mg ACTH-test, the result of which will be revealed a posteriori, is performed at study inclusion; all patients are instructed on glucocorticoid stress cover dosing. Follow-up is for 6 months. The composite primary outcome measure is time to hospitalization, death, initiation of unplanned systemic glucocorticoid therapy, or adrenal crisis. Secondary outcomes include the individual components of the primary outcome, cumulative glucocorticoid doses, signs and symptoms of hypocortisolism, and the performance of the ACTH test in predicting the clinical outcome. Cox proportional hazard, linear, and logistic regression models will be used for statistical analysis.

CONCLUSION

This trial aims to demonstrate the clinical noninferiority and safety of abrupt treatment cessation after ≥28 days of systemic glucocorticoid therapy in patients with stabilized underlying disease.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03153527; EUDRA-CT: 2020-005601-48 https://clinicaltrials.gov/ct2/show/NCT03153527?term=NCT03153527&draw=2&rank=1.

German guideline diverticular disease/diverticulitis: Part II: Conservative, interventional and surgical management

Diverticulosis and diverticular disease are ranked among the most common gastroenterological diseases and conditions. While for many years diverticulitis was found to be mainly an event occurring in the elder population, more recent work in epidemiology demonstrates increasing frequency in younger subjects. In addition, there is a noticeable trend towards more complicated disease. This may explain the significant increase in hospitalisations observed in recent years. It is not a surprise that the number of scientific studies addressing the clinical and socioeconomic consequences in the field is increasing. As a result, diagnosis and conservative as well as surgical management have changed in recent years. Diverticulosis, diverticular disease and diverticulitis are a complex entity and apparently an interdisciplinary challenge. To meet theses considerations the German Societies for Gastroenterology and Visceral Surgery decided to create joint guidelines addressing all aspects in a truely interdisciplinary fashion. The aim of the guideline is to summarise and to evaluate the current state of knowledge on diverticulosis and diverticular disease and to develop statements as well as recommendations to all physicians involved in the management of patients with diverticular disease.

German guideline diverticular disease/diverticulitis: Part I: Methods, pathogenesis, epidemiology, clinical characteristics (definitions), natural course, diagnosis and classification

Diverticulosis and diverticular disease are ranked among the most common gastroenterological diseases and conditions. While for many years diverticulitis was found to be mainly an event occurring in the elder population, more recent work in epidemiology demonstrates increasing frequency in younger subjects. In addition, there is a noticeable trend towards more complicated disease. This may explain the significant increase in hospitalisations observed in recent years. It is not a surprise that the number of scientific studies addressing the clinical and socioeconomic consequences in the field is increasing. As a result, diagnosis and conservative as well as surgical management have changed in recent years. Diverticulosis, diverticular disease and diverticulitis are a complex entity and apparently an interdisciplinary challenge. To meet theses considerations the German Societies for Gastroenterology and Visceral Surgery decided to create joint guidelines addressing all aspects in a truely interdisciplinary fashion. The aim of the guideline is to summarise and to evaluate the current state of knowledge on diverticulosis and diverticular disease and to develop statements as well as recommendations to all physicians involved in the management of patients with diverticular disease.

Determination of tidal volume by electrical impedance tomography (EIT) after indirect two-point calibration

OBJECTIVE

A linear relationship between impedance change (△Z) measured by thoracic electrical impedance tomography (EIT) and tidal volume (VT) has been demonstrated. This study evaluated the agreement between the displayed VT calculated by the EIT software (VT_EIT) and spirometry (VT_SPIRO) after an indirect two-point calibration.

APPROACH

The EIT software was programmed to execute a bedside two-point calibration from the subject-specific, linear equation defining the relationship between △Z and VT_SPIROand displaying VT_EITbreath-by-breath in 20 neutered male, juvenile pigs. After EIT calibration VTs of 8, 12, 16 and 20 mL kg^-1were applied to the lungs. VT_EITand VT_SPIROwere recorded and analysed using Bland-Altman plot for multiple subject measurements. Volumetric capnography (VCap) and spirometry data were explored as components of variance using multiple regression.

MAIN RESULTS

A mean relative difference (bias) of 0.7% with 95% confidence interval (CI) of -10.4 - 10.7% were found between VT_EITand VT_SPIROfor the analysed data set. The variance in VT_EITcould not be explained by any of the measured VCap or spirometry variables.

SIGNIFICANCE

The narrow CI estimated in this study allows the conclusion that EIT and its software can be used to measure and accurately convert △Z into mililitre VT at the bedside after applying an indirect two-point calibration.

Evaluation of a Novel CLIA Monotest Assay for the Detection of Anti-Hepatitis E Virus-IgG and IgM: A Retrospective Comparison with a Line Blot and an ELISA

Despite the increasing relevance of Hepatitis E, an emerging disease endemic in developing and with increasing numbers of sporadic cases in industrialized countries, commercial tests are mainly based on batch oriented serological assays. In this retrospective study, we compared a line immunoassay (LIA; recomLine HEV, Mikrogen) and an ELISA (EIA; Anti-Hepatitis E Virus ELISA, Euroimmun) with a novel chemoluminescence immunoassay in a monotest format (CLIA; Hepatitis E VirClia, Vircell). Twenty sera of PCR proven cases of hepatitis E and 68 blood samples serologically pre-characterized were included. Applying the WHO reference standard, the CLIA demonstrated the highest analytical sensitivity for IgG and IgM. The combinations of CLIA/EIA (IgG and IgM) and CLIA/LIA (IgG) measurements showed substantial correlation. Compared to overall antibody detection (seropositivity in ≥2 assays), CLIA correlation was excellent, outperforming LIA (IgM) and EIA (IgG and IgM). Minor IgM cross reactivity in samples of patients with acute EBV infection was observed in all three assays. The CLIA showed good performance in diagnostic samples compared to established LIA and EIA assays. Due to its ready-to-use monotest format, the CLIA allows simple, time- and cost-effective handling of single samples. These qualities make the assay suitable for diagnostics, especially in the emergency setting and for low-throughput laboratories.

Integrative analysis of cell state changes in lung fibrosis with peripheral protein biomarkers

The correspondence of cell state changes in diseased organs to peripheral protein signatures is currently unknown. Here, we generated and integrated single-cell transcriptomic and proteomic data from multiple large pulmonary fibrosis patient cohorts. Integration of 233,638 single-cell transcriptomes (n = 61) across three independent cohorts enabled us to derive shifts in cell type proportions and a robust core set of genes altered in lung fibrosis for 45 cell types. Mass spectrometry analysis of lung lavage fluid (n = 124) and plasma (n = 141) proteomes identified distinct protein signatures correlated with diagnosis, lung function, and injury status. A novel SSTR2+ pericyte state correlated with disease severity and was reflected in lavage fluid by increased levels of the complement regulatory factor CFHR1. We further discovered CRTAC1 as a biomarker of alveolar type-2 epithelial cell health status in lavage fluid and plasma. Using cross-modal analysis and machine learning, we identified the cellular source of biomarkers and demonstrated that information transfer between modalities correctly predicts disease status, suggesting feasibility of clinical cell state monitoring through longitudinal sampling of body fluid proteomes.

Association of CMV-specific T-cell immunity and risk of CMV infection in lung transplant recipients

BACKGROUND

Protecting against CMV infection and maintaining CMV in latent state are largely provided by CMV-specific T-cells in lung transplant recipients. The aim of the study was to assess whether a specific T-cell response is associated with the risk for CMV infection in seronegative patients who are at high risk for delayed CMV infection.

METHODS

All CMV-seronegative recipients (R-) from CMV-seropositive donors (D+) between January 2018 and April 2019 were included and retrospectively screened for CMV infection before and after assessment of CMV-specific cell-mediated immunity.

RESULTS

Thirty-one of the 50 patients (62%) developed early-onset CMV infection. Lower absolute neutrophil counts were significantly associated with early-onset CMV infection. Antiviral prophylaxis was ceased after 137.2 ± 42.8 days. CMV-CMI were measured at a median of 5.5 months after LTx. 19 patients experienced early and late-onset CMV infection after prophylaxis withdrawal within 15 months post transplantation. Positive CMV-CMI was significantly associated with lower risk of late-onset CMV infection after transplantation in logistic and cox-regression analysis (OR=0.05, p = .01; OR=2,369, p = .026).

CONCLUSION

D+/R- lung transplant recipients are at high risk of developing early and late-onset CMV infection. Measurement of CMV-CMI soon after transplantation might further define the CMV infection prediction risk in LTx recipients being at high risk for CMV viremia.

Epidemiology and transmission characteristics of early COVID-19 cases, 20 January-19 March 2020, in Bavaria, Germany

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) led to a significant disease burden and disruptions in health systems. We describe the epidemiology and transmission characteristics of early coronavirus disease 2019 (COVID-19) cases in Bavaria, Germany. Cases were reverse transcription polymerase chain reaction (RT-PCR)-confirmed SARS-CoV-2 infections, reported from 20 January-19 March 2020. The incubation period was estimated using travel history and date of symptom onset. To estimate the serial interval, we identified pairs of index and secondary cases. By 19 March, 3546 cases were reported. A large proportion was exposed abroad (38%), causing further local transmission. Median incubation period of 256 cases with exposure abroad was 3.8 days (95%CI: 3.5-4.2). For 95% of infected individuals, symptom onset occurred within 10.3 days (95%CI: 9.1-11.8) after exposure. The median serial interval, using 53 pairs, was 3.5 days (95%CI: 3.0-4.2; mean: 3.9, s.d.: 2.2). Travellers returning to Germany had an important influence on the spread of SARS-CoV-2 infections in Bavaria in early 2020. Especially in times of low incidence, public health agencies should identify holiday destinations, and areas with ongoing local transmission, to monitor potential importation of SARS-CoV-2 infections. Travellers returning from areas with ongoing community transmission should be advised to quarantine to prevent re-introductions of COVID-19.

Composition of HBsAg is predictive of HBsAg loss during treatment in patients with HBeAg-positive chronic hepatitis B

BACKGROUND & AIMS

During treatment of chronic HBV infections, loss or seroconversion of the HBV surface antigen (HBsAg) is considered a functional cure. HBsAg consists of the large (LHBs), middle (MHBs), and small surface protein (SHBs) and their relative proportions correlate strongly with disease stage. Our aim was to assess the association between HBsAg composition and functional cure during treatment.

METHODS

A total of 83 patients were retrospectively analyzed. HBsAg loss was achieved by 17/64 patients during nucleos(t)ide analogue (NA) treatment and 3/19 patients following treatment with pegylated interferon-alfa2a (PEG-IFN) for 48 weeks. Sixty-three patients without HBsAg loss were matched as controls. LHBs, MHBs and SHBs were quantified in sera collected before and during treatment.

RESULTS

Before treatment, median MHBs levels were significantly lower in patients with subsequent HBsAg loss than in those without (p = 0.005). During treatment, MHBs and LHBs proportions showed a fast decline in patients with HBsAg loss, but not in patients with HBV e antigen seroconversion only or patients without serologic response. MHBs became undetectable by month 6 of NA treatment in all patients with HBsAg loss, which occurred on average 12.8 ± 8.7 (0-52) months before loss of total HBsAg. Receiver-operating characteristic analyses revealed that the proportion of MHBs was the best early predictor of HBsAg loss before NA treatment (AUC = 0.726, p = 0.019). In patients achieving HBsAg loss with PEG-IFN, the proportions of MHBs and LHBs showed similar kinetics.

CONCLUSION

Quantification of HBsAg proteins shows promise as a novel tool to predict early treatment response. These assessments may help optimize individual antiviral treatment, increasing the rates of functional cure in chronically HBV-infected patients.

LAY SUMMARY

The hepatitis B surface antigen (HBsAg) is a key serum marker for viral replication. Loss of HBsAg is considered stable remission, which can be achieved with antiviral treatments. We have investigated whether the ratios of the different components of HBsAg, namely the large (LHBs) and medium (MHBs) HBsAg during different treatments are associated with the occurrence of HBsAg loss. We found that LHBs and MHBs decrease earlier than total HBsAg before HBsAg loss and we propose LHBs and MHBs as promising novel biomarker candidates for predicting cure of HBV infection.

Repertoire and Neutralizing Activity of Antibodies Against Hepatitis C Virus E2 Peptide in Patients With Spontaneous Resolution of Hepatitis C

Neutralizing antibodies can prevent hepatitis C virus (HCV) infection, one of the leading causes of cirrhosis and liver cancer. Here, we characterized the immunoglobulin repertoire of memory B-cell antibodies against a linear epitope in the central front layer of the HCV envelope (E2; amino acids 483-499) in patients who were infected in a single-source outbreak. A reverse transcription polymerase chain reaction-based immunoglobulin gene cloning and recombinant expression approach was used to express monoclonal antibodies from HCV E2 peptide-binding immunoglobulin G-positive memory B cells. We identified highly mutated antibodies with a neutralizing effect in vitro against different genotype isolates sharing similar gene features. Our data confirm the importance of VH1-69 use for neutralizing activity. The data offer a promising basis for vaccine research and the use of anti-E2 antibodies as a means of passive immunization.

Travel-associated neurological disease terminated in a postmortem diagnosed atypical HSV-1 encephalitis after high-dose steroid therapy - a case report

Background

Human encephalitis can originate from a variety of different aetiologies, of which infection is the most common one. The diagnostic work-up is specifically challenging in patients with travel history since a broader spectrum of unfamiliar additional infectious agents, e. g. tropical disease pathogens, needs to be considered. Here we present a case of encephalitis of unclear aetiology in a female traveller returning from Africa, who in addition developed an atypical herpes simplex virus (HSV) encephalitis in close temporal relation with high-dose steroid treatment.

Case presentation

A previously healthy 48-year-old female presented with confusion syndrome and impaired vigilance which had developed during a six-day trip to The Gambia. The condition rapidly worsened to a comatose state. Extensive search for infectious agents including a variety of tropical disease pathogens was unsuccessful. As encephalitic signs persisted despite of calculated antimicrobial and antiviral therapy, high-dose corticosteroids were applied intravenously based on the working diagnosis of an autoimmune encephalitis. The treatment did, however, not improve the patient’s condition. Four days later, bihemispheric signal amplification in the insular and frontobasal cortex was observed on magnetic resonance imaging (MRI). The intracranial pressure rapidly increased and could not be controlled by conservative treatment. The patient died due to tonsillar herniation 21 days after onset of symptoms. Histological examination of postmortem brain tissue demonstrated a generalized lymphocytic meningoencephalitis. Immunohistochemical reactions against HSV-1/2 indicated an atypical manifestation of herpesviral encephalitis in brain tissue. Moreover, HSV-1 DNA was detected by a next-generation sequencing (NGS) metagenomics approach. Retrospective analysis of cerebrospinal fluid (CSF) and serum samples revealed HSV-1 DNA only in specimens one day ante mortem.

Conclusions

This case shows that standard high-dose steroid therapy can contribute to or possibly even trigger fulminant cerebral HSV reactivation in a critically ill patient. Thus, even if extensive laboratory diagnostics including wide-ranging search for infectious pathogens has been performed before and remained without results, continuous re-evaluation of potential differential diagnoses especially regarding opportunistic infections or reactivation of latent infections is of utmost importance, particularly if new symptoms occur.

Accuracy, precision, and consistency of methods for pathogen-specific cerebrospinal fluid/serum Q-value calculation

For a CSF/serum samples pair the specific Q-value is the ratio of antibody concentrations and proportional to the pathogen-specific antibody index. It is usually extracted from optical density (OD) measurements by applying appropriate evaluation methods. Six different methods for Q-value determination, partly using parameter variation, were assessed with respect to accuracy, precision, and the methods' parameter consistency. The methods are based on the Four Parameters Logistic (4PL) equation or the α-method; one method is a polygonal line composed of calibration data. We tested on OD data of 51 CSF/serum sample pairs, measured with EUROIMMUN AG (Lübeck, Germany) ELISA tests for antibody determination in CSF, as part of INSTAND e.V. proficiency survey tests for the MRZH reaction (Measles, Rubella, Varicella zoster, Herpes simplex virus). Each method was tested with four ODs, standard curve methods additionally with only two ODs, identified by a selection rule. We found all methods to be of comparable accuracy and precision. With the standard curve methods, there were no differences between two ODs and four ODs evaluations. Consistency between method parameters and measured OD values is a key property of standard curve methods with a strong impact on accuracy and precision. We found a statistically significant difference with parameter consistency between a 4PL standard curve evaluation of this study and an α-method evaluation of data, measured with ELISAs of Siemens Healthcare GmbH (Marburg, Germany). General considerations show Q-values obtained by parameter variation to be more reliable than those resulting from selection rule application with standard curves.

Serum HBV RNA as a Predictor of Peginterferon Alfa-2a Response in Patients With HBeAg-Positive Chronic Hepatitis B

Background

Hepatitis B virus (HBV) RNA is a novel serum biomarker that has the potential to predict treatment response in patients with chronic hepatitis B. We explored whether HBV RNA serum levels can predict hepatitis B e antigen (HBeAg) seroconversion in patients treated with peginterferon alfa-2a.

Methods

Serum samples from HBeAg-positive patients previously treated with peginterferon alfa-2a in 2 large randomized controlled trials were retrospectively analyzed. HBV RNA levels were measured using a real-time polymerase chain reaction assay. Ability of individual biomarkers to predict HBeAg seroconversion at 24 weeks posttreatment was evaluated using receiver operating characteristics (ROC) analyses.

Results

The study included 131 subjects (70% male, 96% Asians, 35% HBV genotypes B, and 61% C), 76 treated with peginterferon alfa-2a alone and 55 in combination with lamivudine. Median HBV RNA levels were significantly lower, at all timepoints, in patients achieving HBeAg seroconversion. Levels of HBV RNA at treatment weeks 12 and 24 showed good ability to predict HBeAg seroconversion (area under ROC scores >0.75, P < .001). A HBV RNA cutoff of >5.5 log10 copies/mL identified 30% of nonresponders at week 12 (negative predictive value >90%).

Conclusion

Serum HBV RNA is an early predictor of HBeAg seroconversion in patients treated with peginterferon alfa-2a.

Clinical Trials Registration

NCT01705704.

The PBS Score - a clinical assessment tool for the ambulatory and recurrent clubfoot

PURPOSE

The signs for clubfoot relapse are poorly defined in the literature and there is a lack of a scoring system that allows assessment of clubfeet in ambulatory children. The aim of this study is to develop an easy to use, reliable and validated evaluation tool for ambulatory children with a history of clubfoot.

METHODS

A total of 52 feet (26 children, 41 clubfeet, 11 unaffected feet) were assessed. Three surgeons used the seven-item PBS Score to rate hindfoot varus, standing and walking supination, early heel rise, active/passive ankle dorsiflexion and subtalar abduction blinded to the other examiners. All parents answered the modified Roye score questionnaire prior to the clinical assessment. Correlation between the mean PBS Score and the Roye score was evaluated using Spearman's rank correlation coefficient. Interobserver reliability was tested using weighted and unweighted Cohen's Kappa coefficients.

RESULTS

The Spearman's rank correlation coefficient for correlation between mean PBS Score and Roye score was 0.73 (moderate to good correlation).The interobserver agreement for the total PBS Score resulted in an intraclass correlation coefficient of 0.93 (almost perfect agreement).

CONCLUSION

The PBS score is an easy to use, clinical assessment tool for walking age children with clubfoot deformity. It includes passive and active criteria with a very good interobserver reliability and moderate to good validity.

LEVEL OF EVIDENCE

Level I - Diagnostic study.

Quantification of large and middle proteins of hepatitis B virus surface antigen (HBsAg) as a novel tool for the identification of inactive HBV carriers

OBJECTIVE

Among individuals with chronic hepatitis B, those with hepatitis B e-antigen (HBeAg)-negative chronic hepatitis (CHB) can be difficult to distinguish from those with HBeAg-negative chronic HBV infection, also referred to as inactive HBV carriers (ICs), but both require different medical management. The level of HBV surface antigen (HBsAg) has been proposed as a marker to discriminate between chronic infection and hepatitis stages. HBsAg consists of large, middle and small HBs. The aim of this study was to determine whether the composition of HBsAg improved the identification of ICs among HBsAg-positive subjects with different phases of HBV infections.

DESIGN

HBV large surface proteins (LHBs) and HBV middle surface proteins (MHBs) were quantified in serum samples from 183 clinically well-characterised untreated patients with acute (n=14) HBV infection, ICs (n=44), CHBs (n=46), chronic HBeAg-positive phase (n=68) and hepatitis delta coinfection (n=11) using an ELISA, with well-defined monoclonal antibodies against the preS1 domain (LHBs) and the preS2-domain (MHBs). A Western blot analysis was used to verify the quantitation of the components of HBsAg. Total HBsAg was quantified using a modified commercially available assay (HBsAg V.6.0, Enzygnost, Siemens, Erlangen).

RESULTS

The composition of HBsAg showed specific patterns across different phases of hepatitis B. Individuals in the IC phase had significantly lower proportions of LHBs and MHBs than patients in acute or chronic phases irrespective of their HBV e-antigen status (p<0.0001) or HBsAg level. Both LHBs and MHBs ratios better predicted the IC phase than total HBsAg levels.

CONCLUSION

Quantification of MHBs, particularly LHBs represents a novel tool for the identification of the IC stage.

Multiple-Point Evaluation Algorithms for Enhanced Precision of Pathogen-Specific Cerebrospinal Fluid/Serum Antibody Index Calculation

The determination of pathogen-specific antibody indices (AIs) of CSF and serum is an essential cornerstone in assessing neurological diseases and demands reliable high precision. Various companies provide ELISA kits for the detection of respective antibody concentrations and base AI calculation on a single CSF/serum pair of optical densities (ODs), combined with selection rules. The remainder of OD measurements is not used. There is no averaging of measurement errors and result stabilization. OD data from Siemens Enzygnost ELISA measurements of 2012-2016 proficiency survey samples for measles/rubella/varicella zoster/herpes simplex virus (MRZH) reaction (INSTAND e.V.) were reanalyzed. Several reference methods for calculating Q values from ODs using multiple-point evaluation are described. The methods are based on the α method and the four-parameter logistic (4PL) equation. Statistical analysis shows standard deviations of relative AI differences from AI target values to be significantly lower if derived from multiple-point evaluation instead of single-pair evaluation. Thus, the virus-averaged hit rate of a 10% target AI environment can be improved from 49% up to 69%. Waiving the usage of a standard curve in favor of parameter fitting significantly improves calculational precision for Siemens Enzygnost assays. Patient safety, diagnostic assay costs, and laboratory effectiveness might be improved for other test distributors as well.

Molecular quantification and differentiation of Candida species in biological specimens of patients with liver cirrhosis

Patients with liver cirrhosis are susceptible to fungal infections. Due to low sensitivity of culture-based methods, we applied a real-time PCR assay targeting the 18S rRNA gene in combination with direct sequencing and terminal-restriction fragment length polymorphism (T-RFLP) in order to establish a novel tool to detect fungal DNA and to quantify and differentiate Candida DNA, also in polyfungal specimens. In total, 281 samples (blood n = 135, ascites n = 92, duodenal fluid n = 54) from 135 patients with liver cirrhosis and 52 samples (blood n = 26, duodenal fluid n = 26) from 26 control patients were collected prospectively. Candida DNA was quantified in all samples. Standard microbiological culture was performed for comparison. Blood and ascites samples, irrespective of the patient cohort, showed a method-independent low fungal detection rate of approximately 1%, and the Candida DNA content level did not exceed 3.0x10¹ copies ml^-1 in any sample. In contrast, in duodenal fluid of patients with liver cirrhosis high fungal detection rates were discovered by using both PCR- and culture-based techniques (81.5% vs. 66.7%; p = 0.123) and the median level of Candida DNA was 3.8x10⁵ copies ml^-1 (2.3x10²-6.3x10⁹). In cirrhosis and controls, fungal positive culture results were confirmed by PCR in 96% and an additional amount of 44% of culture negative duodenal samples were PCR positive. Using T-RFLP analysis in duodenal samples, overall 85% of results from microbial culture were confirmed and in 75% of culture-negative but PCR-positive samples additional Candida species could be identified. In conclusion, PCR-based methods and subsequent differentiation of Candida DNA might offer a quick approach to identifying Candida species without prior cultivation.

Peripheral Neurotoxicity following High-Dose Cisplatin with Glutathione: Clinical and Neurophysiological Assessment

The use of high-dose cisplatin is limited by development of severe peripheral neurotoxicity and gradual worsening of renal function. In an ongoing study of high-dose cisplatin glutathione has been employed with the aim of preventing major cisplatin-induced toxicities. Neurotoxicity was examined in detail in 32 patients with ovarian cancer treated with cisplatin (160 mg/m2) and cyclophosphamide (600 mg/m2) every 3-4 weeks for five courses. In addition to serial complete neurological examination, sensory action potentials (SAPs) and motor conduction velocities (MCVs) were also assessed. We confirmed the development of a predominant sensory involvement, characterized by mild distal paresthesias and decrease in vibratory sensibility and in deep tendon reflexes, with a slight reduction of SAPs, observed after three courses of treatment. After five courses, distal paresthesias and disesthesias, decreased proprioception and loss of vibratory sensibility with ataxic signs, absence of deep tendon reflexes, unobtainable SAPs and only moderately reduced MCVs were seen. We did not observe any case of disabling neuropathy. There was a tendency to a more severe involvement of peripheral nerves in patients aged more than fifty. The 3 patients presenting the most serious neuropathy were the oldest in the whole group. Low degree of neurotoxicity observed in this study supports a glutathione protection against cisplatin-induced neurotoxicity. As the urinary excretion of platinum indicated no changes in the renal clearance of cisplatin following repeated courses, the lack of drug accumulation and high plasma peak due to preserved renal function might explain the reduced neurotoxicity observed.

A Preliminary Clinical Experience with Reduced Glutathione as Protector against Cisplatin-Toxicity

A total of 16 consecutive patients (15 with ovarian cancer and 1 with unknown adenocarcinoma) were treated with a standard regimen including cisplatin and cyclophosphamide or with the same regimen in combination with reduced glutathione as potential protective agent against cisplatin nephrotoxicity, in a non-randomized study. Reduced glutathione (1500 mg/m2) was administered prior to each cisplatin administration (90 mg/m2) to seven patients for a maximum of five consecutive courses. A standard hydration protocol without diuretics was used. The patients received a total of 33 courses with glutathione. Glutathione was well tolerated, since it did not produce appreciable side effects. Cisplatin and glutathione combination did not produce unexpected toxicity. Two patients treated with standard regimen without glutathione developed a transient nephrotoxicity. The severity of myelosuppression was reduced following glutathione administration. Moreover, the therapeutic efficacy was not impaired by glutathione pretreatment.

Sex-specific effects of TLR9 promoter variants on spontaneous clearance of HCV infection

OBJECTIVE

As pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of HCV infection is unknown. To address this, TLR9 promoter polymorphisms (single nucleotide polymorphisms (SNPs)) rs187084 and rs5743836 were investigated for their effect on disease progression.

DESIGN

Therefore, the TLR9 SNPs and the interferon lambda 4 (IFNL4) rs12979860 were genotyped in chronically HCV type 1 infected (n=333), in patients who spontaneously cleared the infection (n=161), in the Swiss HCV cohort (n=1057) and the well-characterised German (n=305) and Irish (n=198) 'anti-D' cohorts. Functional analyses were done with promoter reporter constructs of human TLR9 in B cells and assessing TLR9 mRNA levels in whole blood of healthy volunteers.

RESULTS

The TLR9 rs187084 C allele was associated with spontaneous virus clearance in women of the study cohort (OR=2.15 (95% CI 1.18 to 3.90) p=0.012), of the Swiss HCV cohort (OR=2.06 (95% CI 1.02 to 4.18) p=0.044) and in both 'anti-D' cohorts (German: OR=2.01 (95% CI 1.14 to 3.55) p=0.016; Irish: OR=1.93 (95% CI 1.10 to 3.68) p=0.047). Multivariate analysis in the combined study and Swiss HCV cohorts supported the results (OR=1.99 (95% CI 1.30 to 3.05) p=0.002). Functional analyses revealed higher transcriptional activities for both TLR9 variants and an association of the C allele of rs5743836 with allele-specific TLR9 mRNA regulation by oestrogens in women.

CONCLUSIONS

TLR9 promoter SNPs are associated with the natural course of HCV infection and show higher transcriptional activities. Our results imply the DNA sensor TLR9 in natural immunity against the RNA virus, HCV.

Hepatitis C viral dynamics during ribavirin priming differ according to prior treatment response and HCV type

The mode of action of ribavirin is not completely understood. Ribavirin monotherapy has a measurable antiviral effect, which shows great variability. It might lead to an earlier steady state of plasma concentration and therefore enhance the effect of following combination treatment. The aim of this study was to evaluate the antiviral effect of ribavirin priming and its influence on sustained virologic response after combination treatment in a group of patients with different hepatitis C virus (HCV) types with or without prior treatment experience. Retrospective analysis of 75 patients (37 treatment naïve, 20 prior relapse, 16 prior nonresponse, genotype 1 present in 60 patients) from five centres who received ribavirin priming as part of an individual strategy in order to improve treatment outcome. All patients received ribavirin monotherapy with a mean dose of 14.5 mg kg^-1 body weight for a mean of 28 days. After ribavirin priming, dual combination treatment with pegylated interferon alfa and ribavirin was started. The mean HCV RNA decline after ribavirin priming was 0.6 log₁₀  IU mL^-1 (P<.001). The initial viral decline depended on HCV type and previous treatment status being highest among prior relapsers (0.8 log₁₀  IU mL^-1 ; P=.002) and HCV type 2/3 (1.2 log₁₀  IU mL^-1 ; P=.05) and lowest among those with prior nonresponse (0.3 log₁₀  IU mL^-1 , P=.01). IFNL4 (formerly IL28B) genotype for rs12979860 and IFNL3 genotype rs8099917 did not influence the initial viral decline. The study demonstrates a significant variability in the viral dynamics and antiviral efficacy of ribavirin monotherapy, which is mainly influenced by prior treatment status. The fact that the lowest response pattern was observed in prior nonresponder patients to pegylated interferon alfa plus ribavirin combination therapy can be taken as a hint that not only the individual interferon, but also the ribavirin sensitivity contributes significantly to the nonresponsive state.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Apolipoprotein E allele frequencies in chronic and self-limited hepatitis C suggest a protective effect of APOE4 in the course of hepatitis C virus infection

BACKGROUND & AIMS

Infectious hepatitis C virus (HCV) particles bind to host lipoproteins such as low-density lipoproteins (LDLs). Low-density lipoprotein receptors (LDLR) have been termed candidate receptors for HCV-LDL complexes. Functional host genetic single nucleotide polymorphisms (SNPs) in the apolipoprotein E (APOE) gene encoding apolipoprotein E (apoE) - a major structural LDL component and natural ligand of LDLR - likely influence the course of HCV infection. We investigated the prevalence of APOE SNPs in two large and independent cohorts of patients with chronic HCV infection compared to respective controls.

METHODS

We genotyped 996 chronically HCV-infected patients; 179 patients with spontaneous HCV clearance; 283 individuals with non-HCV-associated liver disease; and 2 234 healthy controls.

RESULTS

APOE genotype proportions in patients with persistent HCV infection significantly differed from healthy controls (P = 0.007) primarily because of a substantial under-representation of APOE4 alleles in chronically HCV-infected patients (10.2%) compared to 13.0% in healthy controls (P = 0.001). The distribution of APOE4 allele positive genotypes (ε2ε4, ε3ε4, ε4ε4) also significantly differed between chronically HCV-infected patients and healthy controls (1.4%, 17%, 1% vs. 2.4%, 20.5%, 1.7%; P = 0.001), suggesting a protective effect of the APOE4 allele in HCV infection. This was confirmed by a significant over-representation of the APOE4 allele in patients with spontaneous HCV clearance (17.6%; P = 0.00008). The APOE4 allele distribution in patients with non-HCV-associated liver disease (14.0%) was very similar to healthy controls and also differed from chronically HCV-infected patients (P = 0.012), suggesting HCV specificity.

CONCLUSIONS

Our findings suggest that the APOE4 allele may confer a protective effect in the course of HCV infection.

Splicing controls the ubiquitin response during DNA double-strand break repair

Although evidence that splicing regulates DNA repair is accumulating, the underlying mechanism(s) remain unclear. Here, we report that short-term inhibition of pre-mRNA splicing by spliceosomal inhibitors impairs cellular repair of DNA double-strand breaks. Indeed, interference with splicing as little as 1 h prior to irradiation reduced ubiquitylation of damaged chromatin and impaired recruitment of the repair factors WRAP53β, RNF168, 53BP1, BRCA1 and RAD51 to sites of DNA damage. Consequently, splicing-deficient cells exhibited significant numbers of residual γH2AX foci, as would be expected if DNA repair is defective. Furthermore, we show that this is due to downregulation of the E3 ubiquitin ligase RNF8 and that re-introduction of this protein into splicing-deficient cells restores ubiquitylation at sites of DNA damage, accumulation of downstream factors and subsequent repair. Moreover, downregulation of RNF8 explains the defective repair associated with knockdown of various splicing factors in recent genome-wide siRNA screens and, significantly, overexpression of RNF8 counteracts this defect. These discoveries reveal a mechanism that may not only explain how splicing regulates repair of double-strand breaks, but also may underlie various diseases caused by deregulation of splicing factors, including cancer.

Palm representation and approximation of the covariance of random closed sets

The covariance C(r), r ≥ 0, of a stationary isotropic random closed set Ξ is typically complicated to evaluate. This is the reason that an exponential approximation formula for C(r) has been widely used in the literature, which matches C(0) and C(1)(0), and in many cases also limr→∞C(r). However, for 0 < r < ∞, the accuracy of this approximation is not very high in general. In the present paper, we derive representation formulae for the covariance C(r) and its derivative C(1)(r) using Palm calculus, where r ≥ 0 is arbitrary. As a consequence, an explicit expression is obtained for the second derivative C(2)(0). These results are then used to get a refined exponential approximation for C(r), which additionally matches the second derivative C(2)(0).

White-Light or Narrow-Band Imaging Colonoscopy in Surveillance of Ulcerative Colitis: A Prospective Multicenter Study

BACKGROUND & AIMS

Early detection of neoplastic lesions is essential in patients with long-standing ulcerative colitis but the best technique of colonoscopy still is controversial.

METHODS

We performed a prospective multicenter study in patients with long-standing ulcerative colitis. Two colonoscopies were performed in each patient within 3 weeks to 3 months. In white-light (WL) colonoscopy, stepwise random biopsy specimens (4 biopsy specimens every 10 cm), segmental random biopsies (2 biopsy specimens in 5 segments), and targeted biopsy specimens were taken. In NBI colonoscopy, segmental and targeted biopsy specimens were taken. The sequence of WL and NBI colonoscopy was randomized.

RESULTS

In 36 of 159 patients enrolled (22.6%), 54 lesions with intraepithelial neoplasia (IN) were found (51 low-grade, 3 high-grade). In WL colonoscopy we found 11 IN in stepwise biopsy specimens, 4 in segmental biopsy specimens, and 15 in targeted biopsy specimens. In NBI colonoscopy 7 IN were detected in segmental biopsy specimens and 24 IN were detected in targeted biopsy specimens. Almost all IN were found with one technique alone (κ value of WL vs NBI, -0.86; P < .001). Statistically equivalent numbers of IN were found in NBI colonoscopy with targeted and segmental biopsy specimens as in WL colonoscopy with targeted and stepwise biopsy specimens, but with fewer biopsy specimens (11.9 vs 38.6 biopsy specimens, respectively; P < .001), and less withdrawal time was necessary (23 vs 13 min, respectively; P < .001).

CONCLUSIONS

Stepwise biopsy specimens are indispensable in WL colonoscopy. The combination of targeted and segmental biopsy specimens in the NBI technique is as sensitive as targeted together with stepwise biopsy specimens in WL colonoscopy, but requires fewer biopsy specimens and less time. The highest sensitivity should be reached by combining the WL and NBI techniques by switching between the modes.

Noninvasive characterization of graft steatosis after liver transplantation

OBJECTIVE

Liver graft steatosis has not been noninvasively evaluated yet. We therefore characterized liver transplant recipients by transient elastography (TE) and controlled attenuation parameter (CAP) and correlated the results with clinical and genetic risk factors.

METHODS

A total of 204 patients (pretransplant disease: n = 102 nonalcoholic etiology, nonalcoholic liver cirrhosis (non-ALC); n = 102 alcoholic liver disease, ALC; 42% female; median age 57.8 years; median time since transplantation 66 months) underwent ultrasound, TE, CAP, and nonalcoholic fatty liver disease (NAFLD) fibrosis score. Recipient DNA samples were genotyped for patatin-like phospholipase domain-containing protein 3 (PNPLA3) (rs738409) and IL28B (rs8099917, rs12979860) polymorphisms.

RESULTS

Increased hepatic echogenicity at ultrasound was observed in 36% of patients, CAP values >252 and >300 dB/m indicated steatosis and advanced steatosis in 44% and 24% of individuals. Advanced fibrosis (TE >7.9 kPa) was associated with increased CAP results (266 vs. 229 dB/m, p = 0.012). PNPLA3 G-allele carriers had increased CAP values (257 vs. 222 dB/m, p = 0.032), higher liver stiffness (TE 6.4 vs. 5.5 kPa, p = 0.005), and prevalence of diabetes mellitus (40% vs. 22%, p = 0.016). No such association was observed for IL28B polymorphisms. ALC compared to non-ALC patients had higher body mass index (28.1 vs. 25.5 kg/m², p < 0.001), higher prevalence of diabetes mellitus (41% vs. 25%, p = 0.017), and PNPLA3 CG + GG genotype (73% vs. 47%, p = 0.006), and had elevated TE (6.3 vs. 5.4 kPa, p = 0.022), CAP (266 vs. 221 dB/m, p = 0.001), and NAFLD fibrosis score (score -0.5 vs. -1.3, p < 0.001).

CONCLUSION

Modern noninvasive liver graft assessment frequently detects hepatic steatosis, which is associated with graft fibrosis, components of the metabolic syndrome and recipient PNPLA3 rs738409 genotype, especially in ALC patients.

Non-invasive assessment of hepatic steatosis in patients with NAFLD using controlled attenuation parameter and 1H-MR spectroscopy

Introduction

Non-invasive assessment of steatosis and fibrosis is of growing relevance in non-alcoholic fatty liver disease (NAFLD). ¹H-Magnetic resonance spectroscopy (¹H-MRS) and the ultrasound-based controlled attenuation parameter (CAP) correlate with biopsy proven steatosis, but have not been correlated with each other so far. We therefore performed a head-to-head comparison between both methods.

Methods

Fifty patients with biopsy-proven NAFLD and 15 healthy volunteers were evaluated with ¹H-MRS and transient elastography (TE) including CAP. Steatosis was defined according to the percentage of affected hepatocytes: S1 5-33%, S2 34–66%, S3 ≥67%.

Results

Steatosis grade in patients with NAFLD was S1 36%, S2 40% and S3 24%. CAP and ¹H-MRS significantly correlated with histopathology and showed comparable accuracy for the detection of hepatic steatosis: areas under the receiver-operating characteristics curves were 0.93 vs. 0.88 for steatosis ≥S1 and 0.94 vs. 0.88 for ≥S2, respectively. Boot-strapping analysis revealed a CAP cut-off of 300 dB/m for detection of S2-3 steatosis, while retaining the lower cut-off of 215 dB/m for the definition of healthy individuals. Direct comparison between CAP and ¹H-MRS revealed only modest correlation (total cohort: r = 0.63 [0.44, 0.76]; NAFLD cases: r = 0.56 [0.32, 0.74]). For detection of F2–4 fibrosis TE had sensitivity and specificity of 100% and 98.1% at a cut-off value of 8.85 kPa.

Conclusion

Our data suggest a comparable diagnostic value of CAP and ¹H-MRS for hepatic steatosis quantification. Combined with the simultaneous TE fibrosis assessment, CAP represents an efficient method for non-invasive characterization of NAFLD. Limited correlation between CAP and ¹H-MRS may be explained by different technical aspects, anthropometry, and presence of advanced liver fibrosis.

Impact of ribavirin priming on viral kinetics and treatment response in chronic hepatitis C genotype 1 infection

Ribavirin amplifies the interferon-alpha (IFN) signalling cascade. As ribavirin needs 4 weeks to reach steady state, ribavirin priming may optimize hepatic IFN sensitivity before starting a pegylated (PEG)-IFN/ribavirin combination therapy. This study investigated potential benefits of ribavirin priming prior to PEG-IFN2a/ribavirin combination therapy on viral kinetics, on-treatment and sustained virological response (SVR) in chronic hepatitis C virus (HCV) genotype 1 infection. Sixty-eight treatment naive patients were randomized 2:2:1 to ribavirin (ribavirin arm) or placebo (placebo arm) or PEG-IFN2a (PEG-IFN2a arm) for 6 weeks prior to 12 weeks of PEG-IFN2a/ribavirin combination therapy within a double-blind, placebo-controlled trial. Then, standard PEG-IFN2a/ribavirin combination therapy according to the German guidelines was continued under the responsibility of the investigators. Ribavirin was given according to body weight and PEG-IFN2a at a dose of 180 μg subcutaneously once/week. During ribavirin priming, HCV RNA showed a decline of -0.58 log10  IU/mL (P < 0.001) that was unrelated to the IL28B rs12979860 genotype (CC vs CT/TT, P = 0.244). Ribavirin priming did neither increase the PEG-IFN2a-induced first- or second-phase viral decline (P values >0.100) nor on-treatment response or SVR (HCV RNA undetectable at week 12 of combination therapy: ribavirin arm 56%, placebo arm 38%, PEG-IFN2a arm 50%; SVR: ribavirin arm 41%, placebo arm 54%, PEG-IFN2a arm 50%; P values >0.300). In conclusion, ribavirin monotherapy showed a significant antiviral activity that was not influenced by the IL28B genotype. Ribavirin priming prior to PEG-IFN2a/ribavirin combination therapy did neither increase the first- or second-phase viral decline nor on-treatment response or SVR.

Association of IFNL3 rs12979860 and rs8099917 with biochemical predictors of interferon responsiveness in chronic hepatitis C virus infection

BACKGROUND & AIMS

Genetic variations near the interferon lambda 3 gene (IFNL3, IL28B) are the most powerful predictors for sustained virologic response (SVR) in patients with chronic hepatitis C virus (HCV) infection, compared to other biochemical or histological baseline parameters. We evaluated whether the interplay of both IFNL3 polymorphisms rs12979860 and rs8099917 together with non-genetic clinical factors contributes to the predictive role of these genetic variants.

METHODS

The cohort comprised 1,402 patients of European descent with chronic HCV type 1 infection. 1,298 patients received interferon-based antiviral therapy, and 719 (55%) achieved SVR. The IFNL3 polymorphisms were genotyped by polymerase chain reaction and melting curve analysis.

RESULTS

A significant correlation was found between the IFNL3 polymorphisms and biochemical as well as virologic predictors of treatment outcome such as ALT, GGT, cholesterol, and HCV RNA levels. In multivariate regression analysis, IFLN3 SNPs, HCV RNA levels, and the GGT/ALT ratio were independent predictors of SVR. Dependent on the GGT/ALT ratio and on the HCV RNA concentration, significant variations in the likelihood for achieving SVR were observed in both, carriers of the responder as well as non-responder alleles.

CONCLUSIONS

Our data support a clear association between IFNL3 genotypes and baseline parameters known to impact interferon responsiveness. Improved treatment outcome prediction was achieved when these predictors were considered in combination with the IFNL3 genotype.

[How safe is sedation in gastrointestinal endoscopy? A multicentre analysis of 388,404 endoscopies and analysis of data from prospective registries of complications managed by members of the Working Group of Leading Hospital Gastroenterologists (ALGK)]

BACKGROUND

Gastrointestinal endoscopies are increasingly being carried out with sedation. All of the drugs used for sedation are associated with a certain risk of complications. Data currently available on sedation-associated morbidity and mortality rates are limited and in most cases have substantial methodological limitations. The aim of this study was to record severe sedation-associated complications in a large number of gastrointestinal endoscopies.

METHODS

Data on severe sedation-associated complications were collected on a multicentre basis from prospectively recorded registries of complications in the participating hospitals (median documentation period 27 months, range 9 - 129 months).

RESULTS

Data for 388,404 endoscopies from 15 departments were included in the study. Severe sedation-associated complications occurred in 57 patients (0.01 %). Forty-one percent of the complications and 50 % of all complications with a fatal outcome (10/20 patients) occurred during emergency endoscopies. In addition, it was found that 95 % of the complications and 100 % of all fatal complications affected patients in ASA class ≥ 3.

CONCLUSIONS

Including nearly 400,000 endoscopies, this study represents the largest prospective, multicenter record of the complications of sedation worldwide. The analysis shows that sedation is carried out safely in gastrointestinal endoscopy. The morbidity and mortality rates are much lower than previously reported in the literature in similar groups of patients. Risk factors for the occurrence of serious complications include emergency examinations and patients in ASA class ≥ 3.

Epidemiology and morbidity of Epstein-Barr virus infection in pediatric renal transplant recipients: a multicenter, prospective study

BACKGROUND

The epidemiology and morbidity of Epstein-Barr virus (EBV) infection in pediatric renal transplant recipients have been characterized insufficiently.

METHODS

In a prospective, multicenter study among 106 pediatric kidney allograft recipients aged 11.4 ± 5.9 years, we investigated the epidemiology of EBV infection and the relationship between EBV load, EBV serology, and EBV-related morbidity (posttransplant lymphoproliferative disease [PTLD] or symptomatic EBV infection, defined as flu-like symptoms or infectious mononucleosis).

RESULTS

EBV primary infection occurred in 27 of 43 (63%) seronegative patients and reactivation/reinfection in 28 of 63 (44%) seropositive patients. There was no association between the degree or duration of EBV load and EBV-related morbidity: The vast majority (17 of 18 [94%]) of patients with a high, persistent EBV load remained PTLD-free throughout a follow-up of 5.0 ± 1.3 years, while 2 of 3 (66%) patients with EBV-related PTLD exhibited only a low EBV load beforehand. Eight of 18 (44%) patients with a high, persistent EBV load remained asymptomatic during a follow-up of 5.3 ± 2.9 years. Multivariate analysis identified the EBV high-risk (D(+)/R(-)) serostatus (odds ratio [OR], 7.07; P < .05), the presence of human leukocyte antigen (HLA)-DR7 (OR, 5.65; P < .05), and the intensity of the immunosuppressive therapy (OR, 1.53; P < .01) as independent risk factors for the development of a symptomatic EBV infection.

CONCLUSIONS

Presence of EBV high-risk seroconstellation, HLA-DR7, and intensity of immunosuppressive therapy are significant risk factors for a symptomatic EBV infection, whereas there is no close association between the degree or duration of EBV load and EBV-related morbidity. Clinical Trials Registration. NCT00963248.

Combined effects of different interleukin-28B gene variants on the outcome of dual combination therapy in chronic hepatitis C virus type 1 infection

In patients with chronic hepatitis C virus (HCV) infection, several variants of the interleukin-28B (IL28B) gene have been shown to correlate significantly with a sustained virologic response (SVR). Recent evidence shows that determination of one single IL28B polymorphism, rs12979860, is sufficient for predicting treatment outcome. We examined whether the combined determination of the IL28B single-nucleotide polymorphisms (SNPs), rs12979860, rs8099917, rs12980275, and rs8103142, might improve the prediction of SVR in patients with HCV. In the study cohort, 54% of 942 patients with chronic HCV type 1 infection had SVR. The IL28B SNPs, rs12979860CC and rs8099917TT, correlated significantly with SVR (68% and 62%). The SNPs, rs12980275 and rs8103142, were in strong linkage disequilibrium with rs12979860 and were not included in further analysis. In homozygous carriers of the rs12979860 responder allele C, additional genotyping of the rs8099917 SNP had no effect on response prediction, whereas in carriers of the rs12979860 nonresponder allele, the rs8099917 SNP improved the response prediction. In heterozygous carriers of the rs12979860 nonresponder T allele, SVR rates were 55% in the presence of the rs8099917TT genotype and 40% in patients carrying the rs8099917 TG or GG genotype. Analysis of an independent confirmation cohort of 377 HCV type 1-infected patients verified the significant difference in SVR rates between the combined genotypes, rs12979860CT/rs8099917TT and rs12979860CT/rs8099917TG (38% versus 21%; P = 0.018).

CONCLUSION

Treatment outcome prediction could not be improved in homozygous carriers of the IL28B rs12979860 C responder allele by the additional determination of the rs8099917 SNP. There is evidence that a significant proportion of heterozygous carriers of the rs12979860 T nonresponder allele can profit with respect to SVR prediction by further determination of the rs8099917 SNP. (HEPATOLOGY 2012;55:1700-1710).

The use of a synthetic DNA-antibody complex as external reference for chromatin immunoprecipitation

Chromatin immunoprecipitation (ChIP) is an analytical method used to investigate the interactions between proteins and DNA in vivo. ChIP is often used as a quantitative tool, and proper quantification relies on the use of adequate references for data normalization. However, many ChIP experiments involve analyses of samples that have been submitted to experimental treatments with unknown effects, and this precludes the choice of suitable internal references. We have developed a normalization method based on the use of a synthetic DNA-antibody complex that can be used as an external reference instead. A fixed amount of this synthetic DNA-antibody complex is spiked into the chromatin extract at the beginning of the ChIP experiment. The DNA-antibody complex is isolated together with the sample of interest, and the amounts of synthetic DNA recovered in each tube are measured at the end of the process. The yield of synthetic DNA recovery in each sample is then used to normalize the results obtained with the antibodies of interest. Using this approach, we could compensate for losses of material, reduce the variability between ChIP replicates, and increase the accuracy and statistical resolution of the data.