The influence of the haemodialysis procedure on platelets, coagulation and fibrinolysis

A comparative study on the haemostatic changes in kidney failure patients: Pre- and post- haemodialysis and haemodiafiltration

BACKGROUND

Individuals with kidney failure have a compromised haemostatic system making them susceptible to both thrombosis and bleeding.

OBJECTIVES

Assessment of primary haemostasis in patients treated with either haemodialysis (HD) or haemodiafiltration (HDF) was performed through the measurement of several coagulation-based tests, both pre- and post-dialysis.

PATIENTS/METHODS

41 renal failure patients and 40 controls were recruited. Platelet aggregometry, Factor XIII (FXIII), Fibrinogen, Von Willebrand Factor (VWF) and Soluble P-Selectin (sP-Sel) levels were measured.

RESULTS

Maximum platelet aggregation was diminished in renal patients irrespective of aspirin intake. Post-dialysis, platelet function was exacerbated. Pre-dialysis FXIII levels were similar to the healthy cohort and became elevated post-dialysis. This elevation could not be explained by the relative decrease of water by dialysis. Fibrinogen levels were already elevated pre-dialysis and further increased post-dialysis. This elevation was associated with the relative decrease of water by dialysis. VWF levels in males were similar to the healthy cohort and became elevated post-dialysis. This elevation was associated with dialysis-related water loss. VWF antigen and activity in female patients were already elevated pre-dialysis and further increased post-dialysis with the exception of VWF activity in HDF treated female patients. sP-Sel levels were lower than those of the healthy cohort and became similar to the healthy cohort post-dialysis. This elevation could not be explained by the relative decrease of water by dialysis.

CONCLUSIONS

Whilst platelet aggregometry was diminished, we noted elevated clotting factors such as fibrinogen, FXIII and VWF with no significant differences between HD and HDF-treated patients.

Impact of renal replacement therapy modality on coagulation and platelet function in critically ill patients: A prospective observational study

BACKGROUND

Renal replacement therapy (RRT) may affect coagulation and platelet function in critically ill patients. However, the mechanism and the difference in the impact on coagulation between intermittent hemodialysis (iHD) and continuous renal replacement therapy (CRRT) remains unclear. This study aimed to investigate and compare the impact of iHD and CRRT on coagulation and platelet function.

METHODS

Critically ill patients undergoing RRT were classified into the iHD group or the CRRT group. After the first blood sampling, patients underwent either a single session of hemodialysis or 48 h of CRRT, then a second blood sample was taken. Rotational thromboelastometry (ROTEM), platelet aggregometry and conventional coagulation tests were performed. The primary outcome was a change in extrinsically activated ROTEM (EXTEM) clotting time (CT).

RESULTS

60 dialysis sessions from 56 patients were finally included, with 30 dialysis sessions per group. EXTEM CT was prolonged significantly after dialysis in the iHD group (90 [74, 128] vs. 74 [61, 91], p < 0.001), but did not change in the CRRT group (94.4 ± 29.4 vs. 91.6 ± 22.9, p = 0.986). The platelet aggregation did not change after both iHD and CRRT. A change in EXTEM CT was significantly greater in the iHD group compared to the CRRT group (p = 0.006). The difference in the incidence of bleeding events was insignificant between the two groups (p = 0.301).

CONCLUSIONS

EXTEM CT was significantly prolonged after iHD, but this change was not shown after CRRT. Platelet function was not affected by both dialysis modalities.

Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

BACKGROUND

Hemodialysis (HD) per se is a risk factor for thrombosis. Considering the growing body of evidence on blood-flow restriction (BFR) exercise in HD patients, identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training model. The aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise (RE) with BFR on this molecule.

METHODS

Two hundred and six HD patients volunteered for this study (all with a glomerular filtration rate of <15 mL/min/1.73 m2). The RE + BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD (intradialytic exercise). RE repetitions included concentric and eccentric lifting phases (each lasting 2 s) and were supervised by a strength and conditioning specialist.

RESULTS

Several variables were associated with elevated levels of D-dimer, including higher blood glucose, citrate use, recent cardiovascular events, recent intercurrents, higher inflammatory status, catheter as vascular access, older patients (>70 years old), and HD vintage. Furthermore, RE + BFR significantly increases D-dimer after 4 h. Patients with borderline baseline D-dimer levels (400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range (≥500 ng/mL).

CONCLUSION

These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE + BFR. D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE + BFR.

Outcomes of Endoscopic Retrograde Cholangiopancreatography in End-Stage Renal Disease Patients Undergoing Hemodialysis: A Systematic Review and Pooled Analysis

Background/Aims: The adverse events associated with endoscopic retrograde cholangiopancreatography (ERCP) in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) have not been sufficiently evaluated. This study aimed to review the morbidity and mortality associated with ERCP in ESRD patients on HD using a systematic review and pooled analysis. Methods: A systematic review and pooled analysis were conducted on studies that evaluated the clinical outcomes of ERCP in patients on HD. Random-effect model meta-analyses with subgroup analyses were conducted. The methodological quality of the included publications was evaluated using the risk of bias assessment tool for nonrandomized studies. The publication bias was assessed. Results: A total of 239 studies were identified, and 12 studies comprising 7921 HD patients were included in the analysis. The pooled estimated frequency of bleeding associated with ERCP in HD patients was 5.8% (460/7921). In the subgroup analysis of seven comparative studies, the ERCP-related bleeding rate was significantly higher in HD patients than in non-HD patients (5.5% (414/7544) vs. 1.5% (6734/456,833), OR 3.84; 95% CI 4.26−25.5; p < 0.001). The pooled frequency of post-ERCP pancreatitis was 8.3%. The pooled frequency of bowel perforation was 0.3%. The pooled estimated mortality associated with ERCP was 7.1% The publication bias was minimal. Conclusion: This pooled analysis showed that ERCP-related morbidity and mortality are higher in HD patients than in non-dialysis patients.

Hepatocellular carcinoma in patients with chronic renal disease: Challenges of interventional treatment

Hepatocellular carcinoma (HCC) is a common malignancy worldwide, recognized as the fourth most common cause of cancer related death. Many risk factors, leading to liver cirrhosis and associated HCC, have been recognized, among them viral hepatitis infections play an important role worldwide. Patients suffering from chronic kidney disease (CKD), especially those on maintenance dialysis, show a higher prevalence of viral hepatitis than the general population what increases the risk of HCC onset. In addition, renal dysfunction may have a negative prognostic impact on both immediate and long-term outcomes after malignancy treatment. Several interventional procedures for the treatment of HCC are currently available: thermal ablation, transcatheter arterial chemoembolization, liver surgery or even liver transplantation. The Barcelona Clinic Liver Cancer system provides an evidence-based treatment algorithm to address different categories of patients to the most-effective treatment in consideration of the extension of disease, liver function and performance status. Liver resection and transplantation are usually reserved to patients with early stage HCC and acceptable performance status, while the other treatments are more indicated in case of impaired liver function or locally advanced or unresectable tumors. However, there is no validated treatment algorithm for HCC in CKD patients, mainly due to the rarity of reports in this cohort of patients. Hereby we discuss the available evidences on interventional HCC treatments in CKD patients, and briefly report up-to-date pharmacological therapy for HCC patients affected by viral hepatitis.

Terminal Phase Components of the Clotting Cascade in Patients with End-Stage Renal Disease Undergoing Hemodiafiltration or Hemodialysis Treatment

Hemostasis disorder in patients with end-stage renal disease (ESRD) is frequently associated with bleeding diathesis but it may also manifest in thrombotic complications. Analysis of individual coagulation and fibrinolytic factors may shed light on the background of this paradox situation. Here we explored components essential for fibrin formation/stabilization in ESRD patients being on maintenance hemodiafiltration (HDF) or hemodialysis (HD). Pre-dialysis fibrinogen, factor XIII (FXIII) antigen concentrations and FXIII activity were elevated, while α₂-plasmin inhibitor (α₂PI) activity decreased. The inflammatory status, as characterized by C-reactive protein (CRP) was a key determinant of fibrinogen concentration, but not of FXIII and α₂PI levels. During a 4-h course of HDF or HD, fibrinogen concentration and FXIII levels gradually elevated. When compensated for the change in plasma water, i.e., normalized for plasma albumin concentration, only FXIII elevation remained significant. There was no difference between HDF and HD treatments. Individual HDF treatment did not influence α₂PI activity, however after normalization it decreased significantly. HD treatment had a different effect, α₂PI activities became elevated but the elevation disappeared after normalization. Elevated fibrinogen and FXIII levels in ESRD patients might contribute to the increased thrombosis risk, while decreased α₂PI activity might be associated with elevated fibrinolytic potential.

Clinical outcome of endoscopic retrograde cholangiopancreatography for choledocholithiasis in end-stage renal disease patients on hemodialysis

BACKGROUND/AIMS

Endoscopic retrograde cholangiopancreatography (ERCP) is used as a curative method for choledocholithiasis, but little is known about ERCP for patients with end-stage renal disease (ESRD) on hemodialysis (HD). The aim of the current study was to evaluate the efficacy and safety of ERCP for patients with ESRD on HD and to identify the risk factors of ERCP-related bleeding.

MATERIALS AND METHODS

The medical records of 61 ESRD patients with choledocholithiasis who underwent ERCP were retrospectively investigated with respect to successful bile duct stone removal and procedure-related adverse events such as pancreatitis, bleeding, and cholangitis.

RESULTS

For the study subjects, the overall stone removal success rate was 96.7%, and the overall ERCP-related adverse event rate was 21.3% (pancreatitis, 4.9%; bleeding, 13.1%; cholangitis, 6.6%). Endoscopic sphincterotomy (EST) was found to be associated with hemorrhage (p=0.02), and the occurrence of hemorrhage in patients who underwent EST with or without endoscopic papillary balloon dilation (EPBD) was significantly higher than that in patients who underwent EPBD alone (Odds ratio 1.27, 95% confidence interval 1.075-1.493, p=0.02).

CONCLUSION

ERCP for ESRD patients was found to be feasible and safe. However, EST was significantly related to hemorrhagic events. EPBD reduced the risk of hemorrhage and was as effective as EST in terms of stone removal.

Acquired platelet function disorders

The possibility of an acquired platelet function disorder should be considered in patients who present with recent onset muco-cutaneous bleeding. Despite the availability of newer and faster platelet function assays, light transmission aggregometry (LTA) remains the preferred diagnostic test. This review examines and discusses the causes of acquired platelet dysfunction; most commonly drugs, dietary factors, medical disorders and procedures. In addition to well-known antiplatelet therapies, clinicians should be alert for newer drugs which can affect platelets, such as ibrutinib. There is little clinical trial evidence to guide the management of acquired platelet function defects, but we summarise commonly employed strategies, which include addressing the underlying cause, antifibrinolytic agents, desmopressin infusions, and in selected patients, platelet transfusions.

In-hospital mortality associated with transcatheter arterial embolization for treatment of hepatocellular carcinoma in patients on hemodialysis for end stage renal disease: a matched-pair cohort study using a nationwide database

Objectives:

No previous study has evaluated the risks associated with transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma in patients on hemodialysis (HD) for end stage renal disease (ESRD), because invasive treatment is rarely performed for such patients. We used a nationwide database to investigate in-hospital mortality and complication rates following TACE in patients on HD for ESRD.

Methods:

Using the Japanese Diagnosis Procedure Combination database, we enrolled patients on HD for ESRD who underwent TACE for hepatocellular carcinoma. For each patient, we randomly selected up to four non-dialyzed patients using a matched-pair sampling method based on the patient’s age, sex, treatment hospital, and treatment year. In-hospital mortality and complication rates were compared between dialyzed and non-dialyzed patients following TACE.

Results:

We compared matched pairs of 1551 dialyzed and 5585 non-dialyzed patients. Although the complication rate did not differ between the dialyzed and non-dialyzed ESRD patients [5.7% vs 5.8%, respectively; odds ratio, 0.99; 95% confidence interval (0.79–1.23); p = 0.90], the in-hospital mortality rate was significantly higher in dialyzed ESRD patients than in non-dialyzed patients [2.2% vs 0.97%, respectively; odds ratio, 2.21; 95% confidence interval (1.44–3.40); p < 0.001]. Among the dialyzed patients, the mortality rate was not significantly associated with sex, age, Charlson comorbidity index, or hospital volume.

Conclusions:

The in-hospital mortality rate following TACE was 2.2 % and was significantly higher in dialyzed than in non-dialyzed ESRD patients. The indications for TACE in HD-dependent patients should be considered carefully with respect to the therapeutic benefits vs risks.

Advances in knowledge:

In hospital mortality rate following TACE in dialyzed patients was more than twice compared to non-dialyzed patients. Post-procedural complication following TAE in ESRD onHD patients was 5.7%, and did not differ from that in non dialyzed patients.

Management of hepatitis C virus infection in patients with chronic kidney disease: position statement of the joint committee of Italian association for the study of the liver (AISF), Italian society of internal medicine (SIMI), Italian society of infectious and tropical disease (SIMIT) and Italian society of nephrology (SIN)

Hepatitis C virus (HCV) infection is now considered a systemic disease due to the occurrence of extra-hepatic manifestations. Among these, the renal involvement is frequent. HCV infection, in fact, is strongly associated with proteinuria and chronic kidney disease (CKD) and negatively affects the prognosis of renal patients. In the last few years, availability of more specific and effective drugs against HCV has dramatically changed the clinical course of this disease. These drugs may provide further advantages in the CKD population as a whole by reducing progression of renal disease, mortality rate and by increasing the survival of graft in renal transplant recipients. The strict pathogenetic and prognostic link between HCV infection and CKD requires an ongoing relationship among the healthcare professionals involved in the treatment of both HCV infection and CKD. Therefore, Scientific Societies involved in the care of this high-risk population in Italy have organized a joint expert panel. The aim of the panel is to produce a position statement that can be used in daily clinical practice for the management of HCV infected patients across the whole spectrum of renal disease, from the conservative phase to renal replacement treatments (dialysis and transplantation). Sharing specific evidence-based expertise of different professional healthcare is the first step to obtain a common ground of knowledge on which to instate a model for multidisciplinary management of this high-risk population. Statements cover seven areas including epidemiology of CKD, HCV-induced glomerular damage, HCV-related renal risk, staging of liver disease in patients with CKD, prevention of transmission of HCV in hemodialysis units, treatment of HCV infection and management of HCV in kidney transplantation.

Management of hepatitis C virus infection in patients with chronic kidney disease: position statement of the joint committee of Italian association for the study of the liver (AISF), Italian society of internal medicine (SIMI), Italian society of infectious and tropical disease (SIMIT) and Italian society of nephrology (SIN)

Hepatitis C virus (HCV) infection is now considered a systemic disease due to the occurrence of extra-hepatic manifestations. Among these, the renal involvement is frequent. HCV infection, in fact, is strongly associated with proteinuria and chronic kidney disease (CKD) and negatively affects the prognosis of renal patients. In the last few years, availability of more specific and effective drugs against HCV has dramatically changed the clinical course of this disease. These drugs may provide further advantages in the CKD population as a whole by reducing progression of renal disease, mortality rate and by increasing the survival of graft in renal transplant recipients. The strict pathogenetic and prognostic link between HCV infection and CKD requires an ongoing relationship among the healthcare professionals involved in the treatment of both HCV infection and CKD. Therefore, Scientific Societies involved in the care of this high-risk population in Italy have organized a joint expert panel. The aim of the panel is to produce a position statement that can be used in daily clinical practice for the management of HCV infected patients across the whole spectrum of renal disease, from the conservative phase to renal replacement treatments (dialysis and transplantation). Sharing specific evidence-based expertise of different professional healthcare is the first step to obtain a common ground of knowledge on which to instate a model for multidisciplinary management of this high-risk population. Statements cover seven areas including epidemiology of CKD, HCV-induced glomerular damage, HCV-related renal risk, staging of liver disease in patients with CKD, prevention of transmission of HCV in hemodialysis units, treatment of HCV infection and management of HCV in kidney transplantation.

Management of hepatitis C virus infection in patients with chronic kidney disease: position statement of the joint committee of Italian association for the study of the liver (AISF), Italian society of internal medicine (SIMI), Italian society of infectious and tropical disease (SIMIT) and Italian society of nephrology (SIN)

Hepatitis C virus (HCV) infection is now considered a systemic disease due to the occurrence of extra-hepatic manifestations. Among these, the renal involvement is frequent. HCV infection, in fact, is strongly associated with proteinuria and chronic kidney disease (CKD) and negatively affects the prognosis of renal patients. In the last few years, availability of more specific and effective drugs against HCV has dramatically changed the clinical course of this disease. These drugs may provide further advantages in the CKD population as a whole by reducing progression of renal disease, mortality rate and by increasing the survival of graft in renal transplant recipients. The strict pathogenetic and prognostic link between HCV infection and CKD requires an ongoing relationship among the healthcare professionals involved in the treatment of both HCV infection and CKD. Therefore, Scientific Societies involved in the care of this high-risk population in Italy have organized a joint expert panel. The aim of the panel is to produce a position statement that can be used in daily clinical practice for the management of HCV infected patients across the whole spectrum of renal disease, from the conservative phase to renal replacement treatments (dialysis and transplantation). Sharing specific evidence-based expertise of different professional healthcare is the first step to obtain a common ground of knowledge on which to instate a model for multidisciplinary management of this high-risk population. Statements cover seven areas including epidemiology of CKD, HCV-induced glomerular damage, HCV-related renal risk, staging of liver disease in patients with CKD, prevention of transmission of HCV in hemodialysis units, treatment of HCV infection and management of HCV in kidney transplantation.

Management of hepatitis C virus infection in patients with chronic kidney disease: position statement of the joint committee of Italian association for the study of the liver (AISF), Italian society of internal medicine (SIMI), Italian society of infectious and tropical disease (SIMIT) and Italian society of nephrology (SIN)

Hepatitis C virus (HCV) infection is now considered a systemic disease due to the occurrence of extra-hepatic manifestations. Among these, the renal involvement is frequent. HCV infection, in fact, is strongly associated with proteinuria and chronic kidney disease (CKD) and negatively affects the prognosis of renal patients. In the last few years, availability of more specific and effective drugs against HCV has dramatically changed the clinical course of this disease. These drugs may provide further advantages in the CKD population as a whole by reducing progression of renal disease, mortality rate and by increasing the survival of graft in renal transplant recipients. The strict pathogenetic and prognostic link between HCV infection and CKD requires an ongoing relationship among the healthcare professionals involved in the treatment of both HCV infection and CKD. Therefore, Scientific Societies involved in the care of this high-risk population in Italy have organized a joint expert panel. The aim of the panel is to produce a position statement that can be used in daily clinical practice for the management of HCV infected patients across the whole spectrum of renal disease, from the conservative phase to renal replacement treatments (dialysis and transplantation). Sharing specific evidence-based expertise of different professional healthcare is the first step to obtain a common ground of knowledge on which to instate a model for multidisciplinary management of this high-risk population. Statements cover seven areas including epidemiology of CKD, HCV-induced glomerular damage, HCV-related renal risk, staging of liver disease in patients with CKD, prevention of transmission of HCV in hemodialysis units, treatment of HCV infection and management of HCV in kidney transplantation.

Diagnostic Accuracy of Aspartate Aminotransferase to Platelet Ratio Index and Fibrosis 4 Scores in Predicting Advanced Liver Fibrosis in Patients with End-stage Renal Disease and Chronic Viral Hepatitis: Experience from Pakistan

Objectives

The aim was to assess the diagnostic accuracy of APRI and FIB-4 in assessing the stage of liver fibrosis in end stage renal disease (ESRD) patients with chronic viral hepatitis and to compare the two tests with standard tru-cut liver biopsy.

Material and Methods

The study was conducted at Sindh Institute of Urology and Transplantation Karachi (SIUT) from May 2010 to May 2014. All ESRD patients, being considered as candidates for renal transplantation and in whom liver biopsy was performed were included. Fibrosis stage was assessed on liver biopsy using Ishak scoring system. The serum transaminases and platelet counts were used to calculate APRI and FIB-4 scores.

Results

Out of 109 patients, hepatitis C and B virus infections were present in 104 (95.4%) and 3(2.8%), respectively, while 2 (1.8%) patients had both infections. The mean Ishak fibrosis score was 1.95 ± 2. Advanced fibrosis was noted in 37 (34%) patients. Univariate analysis showed that advanced liver fibrosis was associated with lower platelets counts (P=0.001) and higher aspartate aminotransferase (AST) (P=0.001), alanine aminotransferase (ALT) (P=0.022), APRI score (P=0.001) and FIB-4 score (P=0.001). On logistic regression analysis, only APRI score (P < 0.001) was found to be the independent variable associated with advanced liver fibrosis. APRI score cutoff ≥1 indicating advanced fibrosis showed sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 91.9%, 90.3%, 82.9%, 95.6%, respectively with area under the curve (AUC) of 0.97. Similarly, a FIB-4 score cutoff ≥1.1 had sensitivity, specificity, PPV and NPV of 70.27%, 66.67%, 52% and 81.36%, respectively with AUC of 0.74.

Conclusion

APRI is more accurate noninvasive test for assessing advanced liver fibrosis in ESRD patients as compared to FIB-4. It can be used to obviate the need for liver biopsy in this high risk population.

The hypercoagulability paradox of chronic kidney disease: The role of fibrinogen

BACKGROUND

Chronic kidney disease (CKD) patients have increased rates of bleeding as well as thrombosis. Fibrinogen and platelets combine to generate a mature clot, but in CKD platelets are dysfunctional. Therefore, we hypothesize that CKD patients have increased clot strength due to elevated fibrinogen levels.

METHODS

Retrospective review of CKD patients (n = 84) who had rTEG and fibrinogen levels measured. They were compared to healthy controls (n = 134).

RESULTS

CKD patients had statistically significant increases in ACT, angle, MA and decreases in LY30 compared to controls. Fibrinogen levels were increased in CKD patients compared to reference range. Fibrinogen levels had a positive correlation with MA (rho = 0.709, p < 0.0001) in CKD patients.

CONCLUSIONS

Patients with CKD manifest a coagulopathy consisting of delayed clot formation, but increased final clot strength and decreased clot breakdown. Furthermore, the elevated clot strength is mediated by increased fibrinogen levels in CKD patients.

Mortality and hemorrhagic complications associated with radiofrequency ablation for treatment of hepatocellular carcinoma in patients on hemodialysis for end-stage renal disease: A nationwide survey

BACKGROUND AND AIM

Because of the rarity of invasive treatment for hepatocellular carcinoma (HCC) in patients on hemodialysis (HD) for end-stage renal disease (ESRD), the risks associated with radiofrequency ablation (RFA) in such patients remain uncertain. We used a nationwide database to investigate in-hospital mortality and hemorrhagic complications following RFA in patients on HD for ESRD.

METHODS

Using the Japanese Diagnosis Procedure Combination database, we enrolled patients on HD for ESRD who underwent RFA for HCC. For each patient, we randomly selected up to four non-dialyzed patients using a matched-pair sampling method based on patient age, sex, treatment hospital, and treatment year. In-hospital mortality and hemorrhagic complications were compared between dialyzed and non-dialyzed patients following RFA.

RESULTS

We compared matched-pair samples of 437 dialyzed and 1345 non-dialyzed patients. In patients on HD for ESRD, mortality was significantly lower in those aged ≤70 years than in older patients (P = 0.02). In-hospital mortality was significantly higher in dialyzed ESRD patients than in non-dialyzed patients (1.1% vs 0.15%, respectively; odds ratio = 7.77, P < 0.001). Hemorrhagic complications differed significantly between dialyzed ESRD patients and non-dialyzed patients (3.4% vs 0.87%, respectively; odds ratio = 4.75, P < 0.001).

CONCLUSIONS

In-hospital mortality following RFA was higher in dialyzed ESRD patients than in non-dialyzed patients. The indications for RFA in dialysis-dependent patients should be considered carefully. Patient age may be a useful indicator when considering RFA for HCC in patients on HD for ESRD.

The role of cGMP and its signaling pathways in kidney disease

Cyclic nucleotide signal transduction pathways are an emerging research field in kidney disease. Activated cell surface receptors transduce their signals via intracellular second messengers such as cAMP and cGMP. There is increasing evidence that regulation of the cGMP-cGMP-dependent protein kinase 1-phosphodiesterase (cGMP-cGK1-PDE) signaling pathway may be renoprotective. Selective PDE5 inhibitors have shown potential in treating kidney fibrosis in patients with chronic kidney disease (CKD), via their downstream signaling, and these inhibitors also have known activity as antithrombotic and anticancer agents. This review gives an outline of the cGMP-cGK1-PDE signaling pathways and details the downstream signaling and regulatory functions that are modulated by cGK1 and PDE inhibitors with regard to antifibrotic, antithrombotic, and antitumor activity. Current evidence that supports the renoprotective effects of regulating cGMP-cGK1-PDE signaling is also summarized. Finally, the effects of icariin, a natural plant extract with PDE5 inhibitory function, are discussed. We conclude that regulation of cGMP-cGK1-PDE signaling might provide novel, therapeutic strategies for the worsening global public health problem of CKD.

Influence of ACE I/D Polymorphism on Circulating Levels of Plasminogen Activator Inhibitor 1, D-Dimer, Ultrasensitive C-Reactive Protein and Transforming Growth Factor β1 in Patients Undergoing Hemodialysis

BACKGROUND

There is substantial evidence that chronic renal and cardiovascular diseases are associated with coagulation disorders, endothelial dysfunction, inflammation and fibrosis. Angiotensin-Converting Enzyme Insertion/Deletion polymorphism (ACE I/D polymorphism) has also be linked to cardiovascular diseases. Therefore, this study aimed to compare plasma levels of ultrassensible C-reactive protein (usCRP), PAI-1, D-dimer and TGF-β1 in patients undergoing HD with different ACE I/D polymorphisms.

METHODS

The study was performed in 138 patients at ESRD under hemodialysis therapy for more than six months. The patients were divided into three groups according to the genotype. Genomic DNA was extracted from blood cells (leukocytes). ACE I/D polymorphism was investigated by single polymerase chain reaction (PCR). Plasma levels of D-dimer, PAI-1 and TGF-β1 were measured by enzyme-linked immunosorbent assay (ELISA), and the determination of plasma levels of usCRP was performed by immunonephelometry. Data were analyzed by the software SigmaStat 2.03.

RESULTS

Clinical characteristics were similar in patients with these three ACE I/D polymorphisms, except for interdialytic weight gain. I allele could be associated with higher interdialytic weight gain (P = 0.017). Patients genotyped as DD and as ID had significantly higher levels of PAI-1 than those with II genotype. Other laboratory parameters did not significantly differ among the three subgroups (P = 0.033). Despite not reaching statistical significance, plasma levels of usCRP were higher in patients carrying the D allele.

CONCLUSION

ACE I/D polymorphisms could be associated with changes in the regulation of sodium, fibrinolytic system, and possibly, inflammation. Our data showed that high levels of PAI-1 are detected when D allele is present, whereas greater interdialytic gain is associated with the presence of I allele. However, further studies with different experimental designs are necessary to elucidate the mechanisms involved in these associations.

Spontaneous Extradural Hemorrhage in a Patient with Chronic Kidney Disease: A Case Report and Review of Literature

BACKGROUND

Spontaneous extradural hemorrhage is a rare entity. It is usually reported in association with locoregional disease, which is often infective, inflammatory, and hematologic. Chronic kidney disease with hemodialysis is one of the most infrequent causes. The exact association or pathogenesis remains elusive, although possible mechanisms have been suggested. The presentation, associated comorbid conditions, and management vary among the reported cases.

CASE DESCRIPTION

A 39-year-old man with hypertension, well controlled with medications, and chronic kidney disease was on maintenance hemodialysis. He later underwent Tenckhoff catheter insertion for peritoneal dialysis; 2 weeks later, when peritoneal dialysis was started, he developed breathlessness. The Tenckhoff catheter was removed. However, the patient developed ascitic leak from the surgical site, which was repaired under general anesthesia. In the immediate postoperative period, he developed sudden, severe headache and was found to have bifrontal extradural hemorrhage. He underwent prompt drainage of the hematoma and was discharged on the fifth postoperative day in stable condition.

CONCLUSIONS

We report a rare case of spontaneous bilateral frontal extradural hemorrhage in the immediate postoperative period in a patient on hemodialysis. In addition, we review the existing literature on the topic.

Where and When To Inject Low Molecular Weight Heparin in Hemodiafiltration? A Cross Over Randomised Trial

Background and Objective

Low molecular weight heparins (LMWHs) are small enough to pass large pore dialysis membranes. Removal of LMWH if injected before the start of the session is possible during high-flux dialysis and hemodiafiltration. The aim of this study was to determine the optimal mode (place and time) of tinzaparin administration during postdilution hemodiafiltration.

Study Design, Setting, Patients

In 13 chronic hemodiafiltration patients, 3 approaches of injection were compared in a randomised cross over trial: i) before the start of the session at the inlet blood line filled with rinsing solution (IN₀), ii) 5 min after the start at the inlet line filled with blood (IN₅) and iii) before the start of the session at the outlet blood line (OUT₀). Anti-Xa activity, thrombin generation, visual clotting score and reduction ratios of urea and beta2microglobulin were measured.

Results

Anti-Xa activity was lower with IN₀ compared with IN5 and OUT₀, and also more thrombin generation was observed with IN₀. No differences were observed in visual clotting scores and no clinically relevant differences were observed in solute reduction ratio. An anti-Xa of 0.3 IU/mL was discriminative for thrombin generation. Anti-Xa levels below 0.3 IU/mL at the end of the session were associated with worse clotting scores and lower reduction ratio of urea and beta2microglobulin.

Conclusions

Injection of tinzaparin at the inlet line before the start of postdilution hemodiafiltration is associated with loss of anticoagulant activity and can therefore not be recommended. Additionally, we found that an anti-Xa above 0.3 IU/mL at the end of the session is associated with less clotting and higher dialysis adequacy.

Trial Registration

Clinicaltrials.gov NCT00756145

Feasibility of endoscopic retrograde cholangiopancreatography-related procedures in hemodialysis patients

BACKGROUND AND AIM

The opportunities of endoscopic retrograde cholangiopancreatography (ERCP)-related procedure for hemodialysis (HD) patients have been increasing recently. However, the complication rate of ERCPs in HD patients has not been evaluated sufficiently. We aimed to clarify the feasibility of ERCPs in HD patients.

METHODS

We retrospectively reviewed 76 consecutive ERCPs for HD patients between January 2005 and December 2012 in one university hospital and three tertiary-care referral centers. Endoscopic sphincterotomy (EST) was performed in 21 HD patients. We evaluated the incidence and risk factors for complications of all ERCPs and EST in HD patients.

RESULTS

The incidence of pancreatitis, cholangitis, and cardiopulmonary complications for ERCPs in HD patients was 7.9% (6/76), 1.3% (1/76), and 1.3% (1/76), respectively. The mortality rate was 2.6% (2/76), and it occurred after acute pancreatitis in one patient and pneumonia in the other patient. The incidence of hemorrhage and pancreatitis with EST was 19% (4/21) and 4.8% (1/21), respectively. The duration of HD was significantly longer in the patients with hemorrhage after EST than without (19.5 vs 6 years; P = 0.029).

CONCLUSIONS

ERCP is feasible in HD patients. However, EST is not advisable because of the high hemorrhage rate, particularly for patients with a long duration of HD.

Platelet-Related Hemostasis before and after Hemodialysis with Five Different Anticoagulation Methods

Purpose

To evaluate platelet-related hemostasis during hemodialysis performed with five different anticoagulation methods.

Methods

31 chronic hemodialysis patients, 71% men, aged 57.5 ∓ 17.4 years, participated in our prospective study. Platelet function analyzer PFA -100 closure time (collagen/epinephrine -CEPI, collagen/adenosine diphosphate -CADP) was measured before and after hemodialysis, which was performed consecutively with five different anticoagulation methods: full-dose unfractionated heparin (UFH) and low-molecular weight heparin (LMWH): 31 patients, regional citrate anticoagulation (RCA): 28 patients, low-dose heparin: 25 patients and “heparin-free” dialysis: 9 patients. The degree of clotting in the dialysis system was graded on a 5 point scale.

Results

CEPI (mean ∓ SD, reference range 80-160 sec) before vs. after hemodialysis: UFH: 171.7 ∓ 62.1 vs. 170.8 ∓ 67.3; LMWH: 167.4 ∓ 56.9 vs. 159.4 ∓ 56.4; low-dose heparin: 175.3 ∓ 69.0 vs. 183.1 ∓ 60.5; RCA: 172.6 ∓ 57.4 vs. 161.6 ∓ 57.0; “heparin-free”: 181.7 ∓ 56.8 vs. 209.0 ∓ 66.5; all differences nonsignificant. CADP (mean ∓ SD, reference range: 68-121 sec) before vs. after hemodialysis: UFH: 132.0 ∓ 56.6 vs.146.3 ∓ 68.4; LMWH: 132.4 ∓ 57,0 vs. 123.1 ∓ 50.8; low-dose heparin: 137.2 ∓ 64.2 vs. 143.8 ∓ 55.5; RCA: 140.7 ∓ 48.2 vs. 132.9 ∓ 48.1; “heparin-free”: 137.1 ∓ 68.0 vs.139.2 ∓ 29.7; all differences nonsignificant. Before hemodialysis procedure CEPI was increased in 51.2% and CADP in 48.4% of the patients. The best dialysis system clotting score was found with UFH, LMWH and RCA.

Conclusions

Platelet dysfunction was demonstrated in approximately half of the chronic hemodialysis patients and was not improved after hemodialysis, regardless of the anticoagulation regimen used.

Diagnosis of common dermopathies in dialysis patients: a review and update

Cutaneous abnormalities in patients with end-stage renal disease (ESRD) receiving hemodialysis or peritoneal dialysis may demonstrate signs of their underlying condition or reveal associated disease entities. While a thorough examination of the scalp, skin, mucosa, and nails is integral to establishing a diagnosis, certain conditions will resolve only with dialysis or improvement of their renal disease and others may not require or respond to treatment. Half and half nails, pruritus, xerosis, and cutaneous hyperpigmentation are common manifestations in ESRD. With hemodialysis, uremic frost is no longer prevalent in ESRD patients and ecchymoses have decreased in incidence. Acquired perforating dermatoses are seen in over one-tenth of hemodialysis patients. Metastatic calcinosis cutis and calciphylaxis are both rarely reported, although the latter is seen almost exclusively in the setting of hemodialysis. Diagnosis of nephrogenic systemic fibrosis has historically been challenging; as such, new diagnostic criteria have been proposed. Blood porphyrin profiles are needed to differentiate between porphyria cutanea tarda and pseudoporphyria. We will review and provide an update on the aforementioned common cutaneous manifestations of ESRD in patients receiving dialysis.

Impaired thrombolysis: a novel cardiovascular risk factor in end-stage renal disease

AIMS

End-stage renal disease (ESRD) patients have an excess cardiovascular risk, above that predicted by traditional risk factor models. Prothrombotic status may contribute to this increased risk. Global thrombotic status assessment, including measurement of occlusion time (OT) and thrombolytic status, may identify vulnerable patients. Our aim was to assess overall thrombotic status in ESRD and relate this to cardiovascular risk.

METHODS AND RESULTS

Thrombotic and thrombolytic status of ESRD patients (n = 216) on haemodialysis was assessed using the Global Thrombosis Test. This novel, near-patient test measures the time required to form (OT) and time required to lyse (lysis time, LT) an occlusive platelet thrombus. Patients were followed-up for 276 ± 166 days for major adverse cardiovascular events (MACE, composite of cardiovascular death, non-fatal MI, or stroke). Peripheral arterial or arterio-venous fistula thrombosis was a secondary endpoint. Occlusion time was reduced (491 ± 177 vs. 378 ± 96 s, P < 0.001) and endogenous thrombolysis was impaired (LT median 1820 vs.1053 s, P < 0.001) in ESRD compared with normal subjects. LT ≥ 3000 s occurred in 42% of ESRD patients, and none of the controls. Impaired endogenous thrombolysis (LT ≥ 3000 s) was strongly associated MACE (HR = 4.25, 95% CI = 1.58-11.46, P = 0.004), non-fatal MI and stroke (HR = 14.28, 95% CI = 1.86-109.90, P = 0.01), and peripheral thrombosis (HR = 9.08, 95% CI = 2.08-39.75, P = 0.003). No association was found between OT and MACE.

CONCLUSION

Impaired endogenous thrombolysis is a novel risk factor in ESRD, strongly associated with cardiovascular events.

Impact of chronic kidney disease on outcomes of surgical resection for primary colorectal cancer: a retrospective cohort review

BACKGROUND

Chronic kidney disease, a disease entity increasing in number, may be an obstacle in various aspects of treatment for malignant neoplasm, such as perisurgical management and implementation of chemotherapy.

OBJECTIVE

The aim of this study was to evaluate both short- and long-term outcomes of patients with colorectal cancer who have chronic kidney disease.

DESIGN

This study is a retrospective cohort study of patients.

SETTINGS

This study as conducted at an academic tertiary hospital in Japan.

PATIENTS AND INTERVENTIONS

We investigated 1127 consecutive patients with stages 0 to III primary colorectal cancer who underwent curative resection in our department from January 2001 to December 2010. Based on estimated glomerular filtration rate, patients were classified into stages 0 to 2 (including normal renal function, 882 patients, 78.2%), stages 3 to 4 (226 patients, 20.1%), or stage 5 chronic kidney disease (19 patients, 1.7%).

MAIN OUTCOME MEASURES

Clinicopathological data, perioperative course, frequencies of postoperative complications, adjuvant chemotherapy, and recurrence-free and overall survivals after surgery for colorectal cancer were compared among the 3 different chronic kidney disease stage groups.

RESULTS

Patients with chronic kidney disease stage 5 frequently experienced diabetes mellitus and cardiovascular comorbidities. They were also hypoalbuminemic and anemic and more likely to receive blood transfusions, although estimated blood loss was smaller during surgery than in the other patients. Perioperative cardiovascular complications were more frequent in the chronic kidney disease stages 3 to 4 and 5 groups (5.3%) than those in the stages 0 to 2 group (0.8%, p < 0.0001). However, the frequencies of other complications were similar. There were no differences in the frequency of adjuvant chemotherapy and recurrence-free survival among different chronic kidney disease stages; in contrast, the chronic kidney disease stage 5 group showed a poorer overall survival.

LIMITATIONS

: The study is limited by its retrospective nature.

CONCLUSIONS

From these data, we conclude that surgical resection for colorectal cancer in patients with chronic kidney disease can be performed with acceptable outcomes.

Endoscopic papillary balloon dilation for bile duct stones in patients on hemodialysis

BACKGROUND

Endoscopic papillary balloon dilation (EPBD) is a less hazardous alternative to endoscopic sphincterotomy for managing bile duct stones in patients with a coagulopathy. However, little information on EPBD is available for patients with bile duct stones who are undergoing hemodialysis (HD). We aimed to evaluate the safety and efficacy of EPBD for such patients.

PATIENTS

This was a retrospective cohort study with prospectively collected data for 37consecutive patients with bile duct stones who were undergoing HD and who also underwent EPBD between December 1995 and April 2010 at four institutions in Tokyo, Japan. The main outcome was the safety and efficacy of EPBD for managing bile duct stones in patients undergoing HD.

RESULTS

The bile duct stones were completely removed in one session in 24 patients (64.8%). Overall success was achieved using EPBD alone in all patients. Complications occurred in five patients (13.5%), including two with hemorrhage (5.4%). No hemorrhage developed in any of the 33 patients who had no additional bleeding risk except for HD. Pancreatitis and perforation developed in two (5.4%) and one (2.7%) patient, respectively.

CONCLUSIONS

EPBD seems to be a safe and effective treatment to extract bile duct stones in patients undergoing HD. However, EPBD should be performed carefully in patients with additional bleeding risk factors, such as Child-Pugh class C liver cirrhosis and those taking anti-platelet agents at the time of EPBD.

A prospective randomized study comparing fibrin sealant to manual compression for the treatment of anastomotic suture-hole bleeding in expanded polytetrafluoroethylene grafts

OBJECTIVE

The ideal hemostatic agent for treatment of suture-line bleeding at vascular anastomoses has not yet been established. This study evaluated whether the use of a fibrin sealant containing 500 IU/mL thrombin and synthetic aprotinin (FS; marketed in the United States under the name TISSEEL) is beneficial for treatment of challenging suture-line bleeding at vascular anastomoses of expanded polytetrafluoroethylene (ePTFE) grafts, including those further complicated by concomitant antiplatelet therapies.

METHODS

Over a 1-year period ending in 2010, ePTFE graft prostheses, including arterio-arterial bypasses and arteriovenous shunts, were placed in 140 patients who experienced suture-line bleeding that required treatment after completion of anastomotic suturing. Across 24 US study sites, 70 patients were randomized and treated with FS and 70 with manual compression (control). The primary end point was the proportion of patients who achieved hemostasis at the study suture line at 4 minutes after start of application of FS or positioning of surgical gauze pads onto the study suture line.

RESULTS

There was a statistically significant difference in the comparison of hemostasis rates at the study suture line at 4 minutes between FS (62.9%) and control (31.4%) patients (P < .0001), which was the primary end point. Similarly, hemostasis rates in the subgroup of patients on antiplatelet therapies were 64.7% (FS group) and 28.2% (control group). When analyzed by bleeding severity, the hemostatic advantage of FS over control at 4 minutes was similar (27.8% absolute improvement for moderate bleeding vs 32.8% for severe bleeding). Logistic regression analysis (accounting for gender, age, intervention type, bleeding severity, blood pressure, heparin coating of ePTFE graft, and antiplatelet therapies) found a statistically significant treatment effect in the odds ratio (OR) of meeting the primary end point between treatment groups (OR, 6.73; P < .0001), as well as statistically significant effects for intervention type (OR, 0.25; P = .0055) and bleeding severity (OR, 2.59; P = .0209). The safety profile of FS was excellent as indicated by the lack of any related serious adverse events.

CONCLUSIONS

The findings from this phase 3 study confirmed that FS is safe and its efficacy is superior to manual compression for hemostasis in patients with peripheral vascular ePTFE grafts. The data also suggest that FS promotes hemostasis independently of the patient's own coagulation system, as shown in a representative population of patients with vascular disease under single- or dual-antiplatelet therapies.

Prothrombotic changes in platelet, endothelial and coagulation function following hemodialysis

PURPOSE

Patients on hemodialysis (HD) have an increased risk of thrombotic events, including myocardial infarction and vascular access thrombosis. The study hypothesis is that a single session of dialysis leads to platelet, endothelial and coagulation activation. Our aim is to determine the effect of a single HD session on prothrombotic vascular biomarkers before and after a single session of hemodialysis.

METHODS

Blood samples were taken from the vascular access of 55 patients immediately before and after a hemodialysis session. Platelet function was assessed by (1) flow cytometric measurement of P-selectin expression and fibrinogen binding +/- ADP stimulation, (2) Ultegra rapid platelet function assay (RPFA) using the agonists thrombin receptor activating peptide (TRAP) and arachidonic acid (AA), (3) soluble P-selectin, and (4) soluble CD40L. Coagulation (thrombin-antithrombin III [TAT] and D-dimer), endothelial von Willebrand factor (vWF) and high sensitivity C-Reactive protein (hsCRP) were assessed by ELISA.

RESULTS

Unfractionated heparin was given to all patients during dialysis and 30 patients (55%) were on antiplatelet agents. Post-hemodialysis there were significant increases in unstimulated platelet P-selectin (p=.037), stimulated P-selectin (p<.001), soluble P-selectin (p<.001) and soluble CD40L (p=.036). Stimulated platelet fibrinogen binding was increased post-hemodialysis (p<.001) but unstimulated fibrinogen binding was unchanged. TRAP- (p<.001] and AA-(p=.009) stimulated aggregation were reduced post-hemodialysis. There were increases post-hemodialysis in TAT (p<.001), D-dimer (p<.001), vWF (p<.001) and hsCRP (p=.011).

CONCLUSION

This study has shown that despite heparin therapy, a single session of HD induced increases in platelet, endothelial, and coagulation activation. More effective medical strategies to reduce the prothrombotic state of patients on hemodialysis should be investigated.

Platelet activation, coagulation activation and C-reactive protein in simultaneous samples from the vascular access and peripheral veins of haemodialysis patients

INTRODUCTION

Most studies of haemodialysis (HD) patients compare venous blood samples from controls with samples from the vascular access (VA) of HD patients. We hypothesised that VA samples may be more prothrombotic compared with venous samples.

METHODS

Samples were taken simultaneously from the VA and the contralateral antecubital vein, from 26 patients immediately before HD. Platelet function was assessed by (1) flow cytometric measurement of P-selectin expression and fibrinogen binding (±ADP) and 2) Ultegra rapid platelet function assay. Plasma soluble P-selectin, von Willebrand factor antigen, high sensitivity C-reactive Protein (hs-CRP), thrombin-antithrombin III complex and D-dimer measured by ELISA.

RESULTS

Thrombin receptor activating peptide-induced platelet aggregation (P < 0.001) and hs-CRP (P < 0.001) were higher in VA compared with venous samples. Unstimulated platelet fibrinogen binding (P = 0.016) and ADP-stimulated P-selectin expression (P = 0.008) were lower in VA compared with venous samples. The significant difference in hsCRP persisted when patients taking and not taking antiplatelet therapy were analysed separately, but platelet activation remained significantly different only in the nonantiplatelet group.

CONCLUSION

There are statistically significant differences between sampling sites, although samples from the VA do not appear to be more pro-thrombotic. Future studies comparing HD patients with controls should ensure uniformity of sampling sites to prevent inaccurate conclusions being drawn.

Management of the kidney transplant patient with chronic hepatitis C infection

Chronic Hepatitis C (HCV) infection is an important cause of morbidity and mortality in patients with end-stage renal disease. Renal transplantation confers a survival advantage in HCV-infected patients. Renal transplant candidates with serologic evidence of HCV infection should undergo a liver biopsy to assess for fibrosis and cirrhosis. Patients with Metavir fibrosis score ≤3 and compensated cirrhosis should be evaluated for interferon-based therapy. Achievement of sustained virological response (SVR) may reduce the risks for both posttransplantation hepatic and extrahepatic complications such as de novo or recurrent glomerulonephritis associated with HCV. Patients who cannot achieve SVR and have no live kidney donor may be considered for HCV-positive kidneys. Interferon should be avoided after kidney transplant except for treatment of life-threatening liver injury, such as fibrosing cholestatic hepatitis. Early detection, prevention, and treatment of complications due to chronic HCV infection may improve the outcomes of kidney transplant recipients with chronic HCV infection.

Use of fibrin sealant as a hemostatic agent in expanded polytetrafluoroethylene graft placement surgery

BACKGROUND

The low thrombogenicity, porosity, and limited elasticity of expanded polytetrafluoroethylene (ePTFE) vascular grafts, although beneficial, may exacerbate the problem of suture-line bleeding at vascular anastomoses and consequently lead to increased operating times. The overall objective of this prospective, randomized, controlled, subject-blinded, multicenter phase 2 study was to evaluate the efficacy and safety of a fibrin sealant containing 500 IU/mL thrombin and synthetic aprotinin (FS; marketed in the United States under the name TISSEEL) for hemostasis in subjects undergoing vascular surgery and receiving prosthetic ePTFE vascular grafts.

METHODS

FS was compared with manual compression with surgical gauze pads, a standard of care for hemostasis in vascular surgery. Two FS polymerization/setting times (60 and 120 seconds) were investigated to evaluate influence on the efficacy results. Patients undergoing ePTFE graft placement surgery (N = 73) who experienced bleeding that required treatment after surgical hemostasis were randomized to be treated with FS with clamps opened at 60 seconds (FS-60; N = 26), with FS with clamps opened at 120 seconds (FS-120; N = 24), or with manual compression with surgical gauze pads (control; N = 23). The proportion of subjects achieving hemostasis at 4 minutes (primary endpoint) as well as at 6 and 10 minutes (secondary endpoints) in the three treatment groups was analyzed using logistic regression analysis, taking into account gender, age, type of intervention, severity of bleeding, systolic blood pressure, diastolic blood pressure, heparin coating of the ePTFE graft, and platelet inhibitors.

RESULTS

There were substantial differences in the proportion of subjects who achieved hemostasis at the study suture line at 4 minutes from treatment application between FS-120 (62.5%) and control (34.8%) groups (a 79.6% relative improvement). Logistic regression analyses found a statistically significant treatment effect at the 10% level in the odds ratio (OR) of achieving hemostasis at 4 minutes between the FS-120 and control groups (OR = 3.98, p = 0.0991). Furthermore, it has been shown that the perioperative administration of platelet inhibitors significantly influences (OR = 3.89, p = 0.0607) hemostasis rates at the primary endpoint. No statistically significant treatment effects were found for the other factors. Logistic regression analyses performed on the secondary endpoints demonstrated a significant treatment effect of achieving hemostasis at 6 minutes (OR = 9.92, p = 0.0225) and at 10 minutes (OR = 6.70, p = 0.0708) between the FS-120 and control groups. Statistically significant effects in the logistic regression analyses were found at the 10% level in the OR of achieving hemostasis at 6 and 10 minutes, respectively, for the following factors: FS-120 versus control group (OR = 9.92; p = 0.0225 and OR = 6.70; p = 0.0708, respectively), type of intervention (OR = 0.3; p = 0.0775 and OR = 0.25; p = 0.0402, respectively), and heparin coating of the ePTFE prosthesis (OR = 4.83; p = 0.0413 and OR = 3.65; p = 0.0911, respectively). FS was safe and well-tolerated, as indicated by the lack of any related serious adverse events.

CONCLUSION

The findings from this phase 2 study support the strong safety profile of FS and suggest that it is an efficacious hemostatic agent in ePTFE graft placement surgery, as well as a useful tool in peripheral vascular surgery applications.

Percutaneous radiofrequency ablation of hepatocellular carcinoma in 14 patients undergoing regular hemodialysis for end-stage renal disease

OBJECTIVE

Management of hepatocellular carcinoma is a major problem in the care of patients undergoing regular hemodialysis treatments, mainly because of a high prevalence of hepatitis C virus infection. The purpose of this study was retrospective assessment of the safety and efficacy of percutaneous radiofrequency ablation of hepatocellular carcinoma in the care of patients with end-stage renal disease undergoing regular hemodialysis treatments.

MATERIALS AND METHODS

Between October 2004 and June 2008, 14 carefully selected hemodialysis patients with hepatocellular carcinoma (five naïve, nine recurrent) underwent a total of 19 radiofrequency ablation treatments. An internally cooled or expandable electrode was used. After tumor ablation, the insertion site at the liver surface was subjected to additional ablation to reduce the bleeding risk.

RESULTS

The Child-Pugh score was 6 or better in all patients but one. The number of tumors was one or two, and the tumor diameter was 35 mm or less in all treatments. No complication such as intraperitoneal hemorrhage was found in any treatment. Local tumor progression was found after one treatment and was successfully managed with subsequent radiofrequency ablation. During the mean observation period of 343 days, there was only one death, of heart failure, among the five patients with naïve tumors.

CONCLUSION

The safety and effectiveness of radiofrequency ablation were not compromised in this series of selected patients with hepatocellular carcinoma who were undergoing hemodialysis. Radiofrequency ablation is a promising option for small hepatocellular carcinomas in patients undergoing regular hemodialysis treatments.

Intradialytic and postdialytic platelet activation, increased platelet phosphatidylserine exposure and ultrastructural changes in platelets in children with chronic uremia

The present research evaluated the intradialytic and postdialytic changes in platelet factor-4 and beta-thromboglobulin plasma levels by enzyme-linked immunoadsorbent assay method and platelet aggregation by ADP as well as flow cytometric percentage of annexin-V-positive platelets as a measure of phosphatidylserine externalization and ultrastructural examination of platelets in 37 uremic patients on regular hemodialysis and 25 age-matched and sex-matched controls. Platelet factor-4 plasma levels increased, remain consistently high during hemodialysis session (20.24 +/- 3.05 IU/ml after 30 min, P < 0.001 and 23.67 +/- 3.68 IU/ml after 240 min, P < 0.001) and returned to control values (6.10 +/- 1.54 IU/ml) only after 24 h following the end of the session. beta-Thromboglobulin showed a trend similar to that of platelet factor-4. Platelet aggregation by ADP showed reduced function in comparison with controls (69.32 +/- 12.37 versus 91.95 +/- 1.59%, P < 0.001). Flow cytometric percentage of annexin-V-positive platelet was significantly elevated (P < 0.001) in uremic patients when compared with normal controls. Ultrastructural studies of platelets 30 min after starting of dialysis showed degranulation of its granules and at 240 min showed complete degranulation, whereas in the postdialytic phase (12 h after the end of dialysis) refilled alpha-granules started to appear. Positive correlations were found between platelet concentration and platelet factor-4 and beta-thromboglobulin plasma levels during and after dialysis (P < 0.001) and with annexin-V-positive platelets percentage (P < 0.001). In conclusion, activated platelets were found in chronic hemodialysis patients, a finding that may explain why uremic patients often suffer from thrombotic accidents. The platelet activation is associated with exposure of phosphatidylserine on the platelet exterior. Platelet factor-4 and beta-thromboglobulin are released from platelets as a result of a defect in their granules membrane as shown by the electron microscopy, mainly as a consequence of the blood-membrane contact during dialysis, and they return only slowly to control values.

Efficacy of an intravenous proton pump inhibitor after endoscopic therapy with epinephrine injection for peptic ulcer bleeding in patients with uraemia: a case-control study

BACKGROUND

Patients with peptic ulcer bleeding and uraemia are prone to re-bleeding.

AIM

To compare the efficacy of an intravenous proton pump inhibitor in treating peptic ulcer bleeding in patients with uraemia and those without uraemia.

METHODS

High-risk peptic ulcer bleeding patients received endoscopic therapy with epinephrine (adrenaline) injection plus intravenous omeprazole (40 mg bolus followed by 40 mg infusion every 12 h) for 3 days. Re-bleeding, volume of blood transfusion, hospital stay, need for surgery, and mortality were analysed.

RESULTS

The uraemic group had similar 7-day re-bleeding rate (6/42, 14.29% vs. 6/46, 13.04%, P = 0.865) to that of non-uraemic patients, but more re-bleeding episodes beyond 7 days (4/42, 9.52% vs. 0/46, 0%, P = 0.032, OR [95% CI] = 1.105 [1.002-1.219]) and all-cause mortality (4/42 vs. 0/46 P = 0.032, OR [95% CI] = 1.105 [1.002-1.219]). The uraemic group also had more units of blood transfusion after endoscopic therapy (mean +/- s.d. 4.33 +/- 3.35 units vs. 2.15 +/- 1.65 units, P < 0.001), longer hospital stay (mean +/- s.d. 8.55 +/- 8.12 days vs. 4.11 +/- 1.60 days, P < 0.001) and complications during hospitalization (9/42 vs. 0/46, P = 0.001, OR [95% CI] = 1.273 [1.087-1.490]).

CONCLUSION

Endoscopic therapy with epinephrine injection plus an intravenous proton pump inhibitor can offer protection against early re-bleeding in uraemic patients with peptic ulcer bleeding, but has a limited role beyond 7 days.

Endogenous bradykinin contributes to increased plasminogen activator inhibitor 1 antigen following hemodialysis

Oxidative stress and inflammation predict cardiovascular events in chronic hemodialysis patients. Hemodialysis activates the kallikrein-kinin system, increasing bradykinin. Bradykinin promotes inflammation but also stimulates endothelial release of tissue-plasminogen activator and inhibits platelet aggregation. Understanding the detrimental and beneficial effects of endogenous bradykinin during hemodialysis has implications for the treatment of cardiovascular disease in the hemodialysis population. To test the hypothesis that bradykinin contributes to the inflammatory and fibrinolytic responses to dialysis, we conducted a double-blind, randomized, placebo-controlled crossover study comparing the effect of the bradykinin B(2) receptor blocker HOE-140 with vehicle on markers of oxidative stress, inflammation, fibrinolysis, and coagulation in nine hemodialysis patients without coronary artery disease. Bradykinin receptor antagonism did not affect the mean arterial pressure or heart rate response to dialysis. Monocyte chemoattractant protein 1 (MCP-1) peaked postdialysis; HOE-140 blunted the increase in MCP-1 (5.9 +/- 5.9 versus 25.6 +/- 20.1 pg/ml, P = 0.01). HOE-140 also abolished the increase in plasminogen activator inhibitor 1 (PAI-1) antigen observed at the end of dialysis. In contrast, HOE-140 significantly accentuated the effect of dialysis on F(2)-isoprostanes and P-selectin. Taken together, these results suggest that endogenous bradykinin contributes to increases in MCP-1 and PAI-1 antigen after hemodialysis via its B(2) receptor. Factors that increase the production of bradykinin or decrease its degradation may enhance the inflammatory response to hemodialysis.

Serum levels of YKL-40 and hyaluronic acid as noninvasive markers of liver fibrosis in haemodialysis patients with chronic hepatitis C virus infection

Hepatitis C virus (HCV) infection is highly prevalent among end-stage renal disease (ESRD) patients undergoing haemodialysis and it is an important cause of morbidity and mortality in this population. The aim of this study was to evaluate the diagnostic value of YKL-40 and hyaluronic acid (HA) as noninvasive markers of liver fibrosis in 185 ESRD HCV-infected patients. Significant liver fibrosis was defined as METAVIR F2, F3 or F4 stages. Significant fibrosis was observed in 45 patients (24%). By univariate analysis, higher levels of YKL-40, HA, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) as well as reduced platelet count were associated with fibrosis. However, by multivariate analysis, only AST (P = 0.001), platelet count (P = 0.004) and HA (P = 0.042) were independently associated with significant fibrosis. For the prediction of significant fibrosis, the areas under receiver operating characterictic curve (AUROC) of the regression model (0.798) was significantly higher than the AUROC of YKL-40 (0.607) and HA (0.650). No difference was noted between the AUROC of the regression model and AST to platelet ratio index (APRI) (0.787). Values <8.38 of the regression model showed a negative predictive value of 94% and scores >or=9.6 exhibited a positive predictive value of 65%. If biopsy indication was restricted to scores in the intermediate range of the regression model, it could have been correctly avoided in 61% of the cases. In conclusion, APRI and a model based on AST, platelet count and HA showed better accuracy than YKL-40 and HA (when used solely) for the prediction of significant fibrosis in ESRD HCV-infected patients.

Indirect Complication of AV Graft Thrombectomy-Thrombolysis Secondary to Previously Attempted Placement of a Temporary Hemodialysis Catheter

Common interventional procedures on frequently encountered patients may wrongly place one on a track that deals with the task at hand while not assessing the global patient. Nowhere is this more problematic than in the dialysis population where in the course of achieving and maintaining vascular access, the interventionist becomes exceedingly familiar with each patient and his or her particular clinical history. Unfortunately, events that may have occurred in the past few hours may rarely be overlooked. We present a case of patient mortality as an indirect result of an upper extremity polytetrafluoroethylene graft thrombectomy-thrombolysis procedure that followed attempted nontunneled catheter placement via the groin.

Simple blood tests as noninvasive markers of liver fibrosis in hemodialysis patients with chronic hepatitis C virus infection

HCV infection is common among patients with end-stage renal disease (ESRD) on hemodialysis, and it has been considered an independent risk factor for mortality in this setting. Although liver biopsy in ESRD patients with HCV infection is useful before kidney transplantation, it carries a high risk of complications. We sought to assess the diagnostic value of noninvasive markers to stage liver fibrosis in 203 ESRD HCV-infected patients. Univariate and multivariate analysis were used to identify variables associated with significant fibrosis (METAVIR F2, F3, or F4 stages). Significant liver fibrosis was observed in 48 patients (24%). Logistic regression analysis identified AST and platelet count as independent predictors of significant fibrosis (P < 0.001 and P = 0.001, respectively). The area under the receiver operating characteristic curve of the AST to platelet ratio index (APRI) for predicting significant fibrosis was 0.801. An APRI < 0.40 accurately identified patients with fibrosis stage 0 or 1 in 93% of the cases (NPV = 93%), and all misclassified subjects were F2. A cutoff > or = 0.95 to confirm significant fibrosis had a PPV of 66%. If biopsy indication was restricted to APRI scores in the intermediate range (> or = 0.40 and < 0.95), 52% of liver biopsies could have been correctly avoided.

CONCLUSION

Stage of liver fibrosis can be reliably predicted in ESRD HCV-infected subjects by simple and widely available blood tests such as AST levels and platelet count. These tests might obviate the requirement for a liver biopsy in a significant proportion of those patients.

Expression patterns and action analysis of genes associated with blood coagulation responses during rat liver regeneration

AIM: To study the blood coagulation response after partial hepatectomy (PH) at transcriptional level.

METHODS: After PH of rats, the associated genes with blood coagulation were obtained through reference to the databases, and the gene expression changes in rat regenerating liver were analyzed by the Rat Genome 230 2.0 array.

RESULTS: It was found that 107 genes were associated with liver regeneration. The initially and totally expressing gene numbers occurring in initiation phase of liver regeneration (0.5-4 h after PH), G₀/G₁ transition (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-function reconstruction (66-168 h after PH) were 44, 11, 58, 7 and 44, 33, 100, 71 respectively, showing that the associated genes were mainly triggered in the forepart and prophase, and worked at different phases. According to their expression similarity, these genes were classified into 5 groups: only up-, predominantly up-, only down-, predominantly down-, up- and down-regulation, involving 44, 8, 36, 13 and 6 genes, respectively, and the total times of their up- and down-regulation expression were 342 and 253, respectively, demonstrating that the number of the up-regulated genes was more than that of the down- regulated genes. Their time relevance was classified into 15 groups, showing that the cellular physiological and biochemical activities were staggered during liver regeneration. According to gene expression patterns, they were classified into 29 types, suggesting that their protein activities were diverse and complex during liver regeneration.

CONCLUSION: The blood coagulation response is enhanced mainly in the forepart, prophase and anaphase of liver regeneration, in which the response in the forepart, prophase of liver regeneration can prevent the bleeding caused by partial hepatectomy, whereas that in the anaphase contributes to the structure-function reorganization of regenerating liver. In the process, 107 genes associated with liver regeneration play an important role.