Alexandra Zahn

Alterations of phospholipid concentration and species composition of the intestinal mucus barrier in ulcerative colitis: a clue to pathogenesis.

Background: Phospholipids are essential for the normal function of the intestinal mucus barrier. The objective of this study was to systematically investigate phospholipids in the intestinal mucus of humans suffering from inflammatory bowel diseases, where a barrier defect is strongly supposed to be pathogenetic. Methods: Optimal mucus recovery was first validated in healthy mice and the method was then transferred to the endoscopic acquisition of ileal and colonic mucus from 21 patients with ulcerative colitis (UC), 10 patients with Crohns disease (CD), and 29 healthy controls. Nano‐electrospray ionization tandem mass spectrometry (ESI‐MS/MS) was used to determine phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and sphingomyelin (SM) in lipid extracts of mucus specimens. Results: Human and rodent mucus contained very similar phospholipid species. In the ileal and colonic mucus from patients suffering from UC, the concentration of PC was highly significantly lower (607 ± 147 pmol/100 &mgr;g protein and 745 ± 148 pmol/100 &mgr;g protein) compared to that of patients with CD (3223 ± 1519 pmol/100 &mgr;g protein and 2450 ± 431 pmol/100 &mgr;g protein) and to controls (3870 ± 760 pmol/100 &mgr;g protein and 2790 ± 354 pmol/100 &mgr;g protein); overall, P = 0.0002 for ileal specimens and P < 0.0001 for colonic specimens. Independent of disease activity, patients suffering from UC showed an increased saturation grade of PC fatty acid residues and a higher LPC‐to‐PC ratio. Conclusions: The intestinal mucus barrier of patients with UC is significantly altered concerning its phospholipid concentration and species composition. These alterations may be very important for the pathogenesis of this disease and underline new therapeutic strategies. Inflamm Bowel Dis 2009

Low Levels of Prothrombin Time (INR) and Platelets Do Not Increase the Risk of Significant Bleeding when Placing Central Venous Catheters

Background and Purpose:Central venous catheters are frequently placed in intensive care medicine for multiple indications. The risk of severe bleeding after cannulation is considered to be increased in patients with abnormal coagulation, common in critically ill patients.Patients and Methods:This open prospective trial, performed at two medical intensive care units and one hematology intermediate care ward, investigated whether insertion of a central venous catheter in patients with coagulopathy (prothrombin time ≤ 50% [International Normalized Ratio, INR, ≥ 1.5] and/or platelets ≤ 50 × 109/l) bears an increased risk of bleeding.Results:In 196 patients with and without severe disorders of hemostasis, no significant difference in decrease of hemoglobin after catheter placement was observed. In addition, no correlation between a significant drop in hemoglobin and increased levels of creatinine or urea was seen. Mechanical complications were similar in frequency compared to previous publications.Conclusion:These findings demonstrate that coagulation disorders with altered prothrombin time (INR) or platelets do not increase the risk of significant bleeding when inserting a central venous catheter. Therefore, the prophylactic correction of coagulation by transfusion of blood products or coagulation factors is not necessary before central venous catheter insertion.ZusammenfassungHintergrund und Ziel:Zentralvenöse Katheter werden in der Intensivmedizin häufig und für viele verschiedene Indikationen benötigt. Man geht davon aus, dass bei Patienten mit schlechter Gerinnung das Blutungsrisiko bei der Anlage solcher Katheter erhöht ist. Verminderte Gerinnungswerte finden sich aber häufig bei kritisch Kranken.Patienten und Methodik:Diese offene und prospektive Studie untersuchte, ob Patienten mit einer eingeschränkten Gerinnung (Quick ≤ 50% [Inter national Normalized Ratio, INR, ≥ 1,5] und/oder Thrombozytenzahl ≤ 50 × 109/l) tatsächlich ein erhöhtes Blutungsrisiko bei der Anlage zentralvenöser Katheter aufweisen. Durchgeführt wurde die Studie auf zwei internistischen Intensivstationen und einer hämatologischen Wachstation. Es wurden 196 Patienten mit und ohne eingeschränkte Gerinnungswerte untersucht und verglichen.Ergebnisse:Im Vergleich von Patienten mit eingeschränkter Gerinnung und solchen ohne fand sich kein signifikanter Unterschied im Hinblick auf einen Abfall des Serumhämoglobins nach der Anlage eines zentralvenösen Katheters. Es fand sich ferner auch kein signifikanter Zusammenhang eines Hämoglobinabfalls mit erhöhten Serumkreatinin- oder -harnstoffwerten. Die Anzahl der aufgetretenen mechanischen Komplikationen war vergleichbar mit früheren Studien.Schlussfolgerung:Diese Daten zeigen, dass eine Störung der Gerinnungsaktivität aufgrund eines verminderten Quick-Werts (erhöhten INR-Werts) oder einer verminderten Thrombozytenzahl bei der Anlage eines zentralvenösen Katheters nicht mit einem erhöhten Blutungsrisiko assoziiert ist. Daher ist die prophylaktische Optimierung der Gerinnungsparameter durch Gabe von Transfusionen vor der Anlage eines zentralvenösen Katheters nicht notwendig.

Budd-Chiari Syndrome: Long term success via hepatic decompression using transjugular intrahepatic porto-systemic shunt

BackgroundBudd-Chiari syndrome (BCS) generally implies thrombosis of the hepatic veins and/or the intrahepatic or suprahepatic inferior vena cava. Treatment depends on the underlying cause, the anatomic location, the extent of the thrombotic process and the functional capacity of the liver. It can be divided into medical treatment including anticoagulation and thrombolysis, radiological procedures such as angioplasty and transjugular intrahepatic porto-systemic shunt (TIPS) and surgical interventions including orthotopic liver transplantation (OLT). Controlled trials or reports on larger cohorts are limited due to rare disease frequency. The aim of this study was to report our single centre long term results of patients with BCS receiving one of three treatment options i.e. medication only, TIPS or OLT on an individually based decision of our local expert group.Methods20 patients with acute, subacute or chronic BCS were treated between 1988 and 2008. Clinical records were analysed with respect to underlying disease, therapeutic interventions, complications and overall outcome.Results16 women and 4 men with a mean age of 34 ± 12 years (range: 14-60 years) at time of diagnosis were included. Myeloproliferative disorders or a plasmatic coagulopathy were identified as underlying disease in 13 patients, in the other patients the cause of BCS remained unclear. 12 patients presented with an acute BCS, 8 with a subacute or chronic disease. 13 patients underwent TIPS, 4 patients OLT as initial therapy, 2 patients required only symptomatic therapy, and one patient died from liver failure before any specific treatment could be initiated. Eleven of 13 TIPS patients required 2.5 ± 2.4 revisions (range: 0-8). One patient died from his underlying hematologic disease. The residual 12 patients still have stable liver function not requiring OLT. All 4 patients who underwent OLT as initial treatment, required re-OLT due to thrombembolic complications of the graft. Survival in the TIPS group was 92.3% and in the OLT group 75% during a median follow-up of 4 and 11.5 years, respectively.ConclusionOur results confirm the role of TIPS in the management of patients with acute, subacute and chronic BCS. The limited number of patients with OLT does not allow to draw a meaningful conclusion. However, the underlying disease may generate major complications, a reason why OLT should be limited to patients who cannot be managed by TIPS.

Immunomonitoring of nuclear factor of activated T cells–regulated gene expression: The first clinical trial in liver allograft recipients

Long‐term calcineurin inhibitor (CNI) treatment can cause serious side effects in liver allograft recipients. An optimal risk‐to‐benefit ratio for CNI blood levels has not been established. Pharmacodynamic drug monitoring through the measurement of the CNI biological activity, that is, the expression of nuclear factor of activated T cells (NFAT)–regulated genes, seems to be a promising approach. The residual gene expression (RGE) of NFAT‐regulated genes 2 and 1.5 hours after cyclosporine A (CsA) and tacrolimus (FK‐506) intake was measured in 100 liver allograft recipients with 1 or more years of follow‐up post‐transplantation. The mean RGE in all patients was 62% ± 33%. A significant negative correlation between the CsA (P < 0.0001, r = −0.8026) and FK‐506 peak levels (P < 0.0001, r = −0.6982) and the RGE of all NFAT‐regulated genes was observed. Clinical reliability was proven too. In conclusion, the data presented in this pilot study reveal the applicability of the pharmacodynamic monitoring of CNI efficacy in liver allograft recipients. To confirm the advantage of individualized pharmacodynamic drug monitoring over pharmacokinetic drug monitoring with respect to clinical outcomes, controlled, prospective studies are needed. Liver Transpl, 2011.

Transcript levels of different cytokines and chemokines correlate with clinical and endoscopic activity in ulcerative colitis

BackgroundA definition of disease activity in ulcerative colitis (UC) is difficult. The clinical activity index (CAI) is only an indirect assessment tool of bowel inflammation and the endoscopic activity index (EAI) sometimes cannot reflect the severity of disease to the full extent. Therefore, there is a need for an objective means to quantify inflammatory activity in mucosal biopsies. In our study, we wanted to examine the correlation between transcript levels of interleukin 8 (CXCL8), interferon γ inducible protein 10 (CXCL10), myeloid-related protein 14 (calgranulin B), macrophage inflammatory protein 2 α (CXCL2) with CAI and EAI in UC.MethodsCytokine and chemokine transcripts were quantified using real-time PCR in 49 mucosal biopsies from 27 different patients with UC. Cytokine transcript levels were correlated with CAI and EAI.ResultsThere was a statistically significant positive correlation between CXCL8 (r = 0.30; p < 0.05), CXCL10 (r = 0.40; p < 0.02), calgranulin B (r = 0.36; p < 0.03), CXCL2 (r = 0.31; p < 0.05) and CAI. Concerning EAI significant positive correlations for CXCL8 (r = 0.37; p < 0.02), CXCL10 (r = 0.33; p < 0.04), calgranulin B (r = 0.31; p < 0.05) and CXCL2 (r = 0.44; p < 0.05) were found. Low clinical and endoscopic activity was accompanied by low cytokine levels whereas high CAI and EAI were associated with high cytokine levels.ConclusionFrom our data, we conclude that real-time PCR quantification of CXCL8, CXCL10, calgranulin B and CXCL2 in colonic biopsies is a simple and objective method for grading inflammation of intestinal mucosa in UC. CXCL8, CXCL10, calgranulin B and CXCL2 might be used as biomarkers and thus as an objective tool especially in clinical trials to evaluate anti-inflammatory and immunomodulatory regimens.

Pharmacodynamic monitoring of nuclear factor of activated T cell-regulated gene expression in liver allograft recipients on immunosuppressive therapy with calcineurin inhibitors in the course of time and correlation with acute rejection episodes--a prospective study.

BACKGROUND Due to considerable pharmacokinetic (PK) variability, immunosuppression with calcineurin inhibitors (CNIs) remains challenging. The objective of this study was to assess a pharmacodynamic (PD) approach of monitoring nuclear factor of activated T cell (NFAT)-regulated gene expression in the course of time and in correlation with rejection episodes. MATERIAL/METHODS 22 de novo liver allograft recipients were observed for a period of up to 12 months and the residual gene expression (RGE) of NFAT-regulated genes was monitored prospectively and correlated to acute rejection episodes. RESULTS There was a significant increase in RGEs between the time points 4-7 months and 1 month (25±7 µg/l vs. 9±5 µg/l, p≤0.0001) and 8-12 months and 1 month (50±8 µg/l vs. 10±7 µg/l, p=0.002) in the cyclosporine A (CsA) group, whereas in the tacrolimus (Tac) group a significant increase in RGEs appeared at the time point 8-12 months first. Acute rejection episodes occurred in 4 patients within 1 month after transplantation. These patients demonstrated a higher RGE of all NFAT-regulated genes compared to the other patients (CsA-treated patients: 39±0% vs. 11±5%, p=0.0001, Tac-treated patients: 48±12% vs. 18±10%, p=0.0082). CONCLUSIONS RGE of all NFAT-regulated genes show a relation between acute rejection episodes in the early post transplant period. Thus, this PD method has the potential to aid therapeutic drug monitoring.

Factors influencing long-term quality of life and depression in German liver transplant recipients: a single-centre cross-sectional study.

BACKGROUND Health-related quality of life (HRQOL) following orthotopic liver transplantation (OLT) has become increasingly important. Therefore, we aimed to identify factors affecting HRQOL after OLT. MATERIAL AND METHODS This cross-sectional, single-centre study surveyed 281 OLT patients. Survey tools included the Short Form (SF-36) Health Survey, the Patient Health Questionnaire 9 (PHQ9), and a self-designed employment questionnaire. Patient medical records were reviewed. RESULTS Participants included 187 men (mean age at OLT: 50 [± 11; 13-69] years). Primary indications for OLT were viral hepatitis (28%), alcoholic liver disease (35%), cholestatic liver disease (11%), and others (26%). Follow-up ranged from 2 to 136 months. Clinical factors associated with improved HRQOL were age ≤ 45 years at OLT and current MELD score <=≤ 13. Time after OLT and indication for transplantation affected SF-36 HRQOL. SF-36 physical component summary scales plateaued at 3-years post-OLT and then stabilized. For the SF-36 HRQOL, scores were the lowest in all domains for OLT recipients transplanted for chronic viral hepatitis and for unemployed patients, whereas sex and number of transplantations showed no significant differences. The PHQ9 results showed that depression was significantly more frequent among patients with current MELD score ≥ 13 or impaired liver function and those transplanted for chronic viral hepatitis or unemployed patients. Age and sex did not influence PHQ9 results. CONCLUSIONS Medical and psychosocial support is crucial for long-term HRQOL after OLT. Developing multidisciplinary interventions to address issues such as employment, age, MELD score, and liver function may improve long-term HRQOL in these patients.

Reduced residual gene expression of nuclear factor of activated T cells-regulated genes correlates with the risk of cytomegalovirus infection after liver transplantation.

Pharmacokinetic monitoring of calcineurin inhibitors (CNIs) is unsatisfactory because, at comparable blood concentrations, side effects vary considerably. We recently confirmed the applicability of a pharmacodynamic (PD) assay that measures the suppression of CNI target genes, specifically the suppression of nuclear factor of activated T cells (NFAT)‐regulated genes in liver transplant (LT) recipients. The aim of this prospective study was to prove the clinical reliability of this assay. Therefore, we quantified the residual gene expression (RGE) of NFAT‐regulated genes and evaluated the association between the RGE of NFAT‐regulated genes and the incidence of cytomegalovirus (CMV) infection.

Mycophenolate mofetil combination therapy improves survival after liver transplantation. A single-center retrospective analysis

BACKGROUND Because the immunosuppressive regimen is a modifiable risk factor after orthotopic liver transplantation (OLT), physicians are nowadays aiming at an optimized and individualized strategy for each patient. The aim of this retrospective study was to examine the impact of different immunosuppressive regimens on the long-term outcome post-OLT based on routine, real-life situations, with particular focus on the subgroups of patients with HCC or HCV. MATERIAL AND METHODS Our study included 186 patients who underwent OLT between 1999 and 2008 at the University Hospital Heidelberg, Germany with an available minimum follow-up period of 12 months. Data were collected pre-transplantation, and at 3 months, 6 months, and 12 months post-OLT and every 6 months afterwards. RESULTS We found a statistically significant better 5-year survival in the calcineurin inhibitor (CNI) + mycophenolate mofetil (MMF) group vs. CNI - MMF (p=0.01) in the whole study group, in the HCC group (p=0.008), and in the HCV group (p=0.0163). Furthermore, there was a trend towards a prolonged HCV relapse-free 5-year survival rate in the CNI + MMF group of 85.6% vs. 70.8% in the CNI - MMF group, a trend towards a lower incidence of death secondary to infection (30.8% vs. 69.2%), and a trend towards lower rates of acute rejections (22.6% vs. 29%). The type of CNI administered was irrelevant in all respects. CONCLUSIONS MMF added to immunosuppressive therapy improves patient survival in OLT recipients in general, as well as in patients with HCC and HCV. Prospective studies are needed to determine if a broader application of MMF post-OLT in combination with CNI-tapering could lead to further outcome improvement.