Prevalence and risk factors of pre-diabetes after renal transplantation: a single-centre cohort study in 200 consecutive patients.

BACKGROUND: After renal transplantation, patients are prone to develop impairments in glucose metabolism. In 2005, the American Diabetes Association published new guidelines on the diagnosis of pre-diabetes [plasma glucose levels from 100 to 125 mg/dL fasting or from 140 to 199 mg/dL 2 h after an oral glucose tolerance test (OGTT)]. This study sought to evaluate the prevalence and the potentially associated factors of pre-diabetes in a cohort of renal transplant patients on maintenance immunosuppressive medication. Furthermore, the diagnostic value of HbA1-c measurements in predicting pre-diabetes in transplant patients is undetermined. METHODS: Two hundred consecutive renal transplant patients of our outpatient transplant clinic were evaluated using a standard OGTT. On the day of testing, multiple factors presumably associated with pre-diabetes were assessed via a standardized questionnaire: daily steroid dosage, triglyceride levels, cholesterol levels, estimated glomerular filtration rate (eGFR) [abbreviated Modification of Diet in Renal Disease (MDRD) formula], systolic and diastolic blood pressure, pulse pressure, age, gender, body mass index (BMI), BMI <>30 and <>25, number of renal transplants, number of rejection episodes prior to testing, source of renal transplant, cause of renal failure and medications as related to the prescription of cyclosporine, tacrolimus, mycophenolate mophetil, angiotensin-converting enzyme inhibitors, AT1-blockers, statins, ß-blockers and thiazide diuretics. Patients diagnosed with pre-diabetes were compared to subjects with normal test results. Fishers exact test and the Wilcoxon rank-sum test were applied to compare the two study populations, whereas multivariate logistic regression was used to seek potential risk factors as related to other covariates. Risk ratios (RRs) to develop pre-diabetes were calculated for significant variables. RESULTS: Ten patients had results indicative of post-transplant diabetes whereas data sets of three other patients were incomplete and were thus not included in the analysis. From the remaining 187 patients, 130 (69.5%) displayed normal test results whereas 57 (30.5%) had results indicative of pre-diabetes. On multivariate regression analysis, patients with pre-diabetes were significantly older {55.3 ± 12.1 versus 47.7 ± 12.6 years, P = 0.0007, RRs per 5 years increase 1.28 [95% confidence interval (95% CI) 1.11-1.47]}, had more rejection episodes [0.26 ± 0.48 versus 0.12 ± 0.37, P = 0.0024, RRs per rejection episode 3.99 (95% CI 1.63-9.77)] and showed lower diastolic blood pressure readings [77 ± 10 mmHg versus 81 ± 10 mmHg, P = 0.0362, RR per 5 mmHg decrease 1.14 (95% CI 1.04-1.49)]. CONCLUSIONS: There is a high incidence of latent pre-diabetes among renal transplant recipients. Increasing age, rejection episodes and lower diastolic blood pressure proved to be associated with pre-diabetes. In contrast to post-transplant diabetes, tacrolimus use and HbA1-c levels were not prognostic of pre-diabetes.

Regional citrate versus systemic heparin for anticoagulation in critically ill patients on continuous venovenous haemofiltration: a prospective randomized multicentre trial.

BACKGROUND: Continuous venovenous haemofiltration (CVVH) in the intensive care setting requires anticoagulation to prevent clotting of the extracorporeal circuit. Several protocols avoiding heparin and using regional citrate anticoagulation have been developed to diminish bleeding risks. However, data from randomized trials comparing citrate anticoagulation with systemic heparinization are very limited. METHODS: One hundred and seventy-four patients on mechanical ventilation, requiring renal replacement therapy for acute renal failure, were included in this prospective randomized multicentre trial comparing regional citrate with systemic heparin. The study was performed at nine different intensive care units at university or academic teaching hospitals. The participants were randomized to either CVVH using regional citrate anticoagulation or CVVH using systemic anticoagulation with unfractionated heparin. The primary outcome was to compare treatment efficacy represented by the patients' acid base status on Day 3 and on each consecutive day. Several parameters of safety and efficacy were analysed as secondary outcomes. RESULTS: Comparison of standard bicarbonate from Day 3 to Day 11 revealed no difference between both treatment modalities. Use of citrate resulted in less systemic anticoagulation, a lower risk of bleeding and a longer haemofilter patency. Episodes of hypercalcaemia, hypocalcaemia and the need for additional bicarbonate infusions occurred more often under citrate. The patients' high mortality was not influenced by the mode of anticoagulation. CONCLUSIONS: Citrate may be used as a regional anticoagulant and the only buffering agent in CVVH with adequate treatment efficacy and safety. However, neither citrate nor heparin anticoagulation should be regarded as a therapeutic standard, since there is no advantage of one of these substances with regard to patient mortality.

Mycophenolic acid inhibits the autocrine PDGF-B synthesis and PDGF-BB-induced mRNA expression of Egr-1 in rat mesangial cells.

BACKGROUND: Uncontrolled mesangial cell (MC) proliferation within the context of glomerular disease contributes to the development of glomerulosclerosis. Mesangial autocrine growth factor stimulation has been described as a pathogenic factor. We investigated the effects of mycophenolic acid (MPA), the active metabolite of the immunosuppressant mycophenolate mofetil (MMF), on proliferation factors of cultured rat MCs. MPA was tested on the expression of platelet-derived growth factor-B (PDGF-B) and its receptor beta (PDGFR-beta), the immediate early gene (IEG) c-fos and the early growth response gene-1 (Egr-1), and AP-1 activation. METHODS: Growth-arrested rat MCs were stimulated with 10% fetal calf serum (FCS) or 10-25 ng/ml platelet-derived growth factor-BB (PDGF-BB) in the presence or absence of MPA (0.019-10 microM) with or without guanosine (100 microM). MC proliferation was quantified by 5-bromo-2'-deoxyuridine (BrdU) incorporation and direct cell counting. Cytotoxicity of MPA was evaluated using the MTT and LDH tests. Protein expression of PDGF-B and its receptor PDGFR-beta was quantified by western blot analysis. The effect of MPA on gene expression of PDGF-B, Egr-1 and c-fos was determined by the reverse transcriptase-polymerase chain reaction (RT-PCR). AP-1 activation was analysed by an electrophoretic mobility shift assay (EMSA). RESULTS: Exposure of MCs to MPA caused a concentration-dependent inhibition of FCS-induced cell proliferation (cell number increase) with an IC50 of 0.44 +/- 0.03 microM and DNA synthesis with an IC50 of 0.52 +/- 0.02 microM without cell cytotoxicity in the therapeutic range. MPA decreased the PDGF-B protein expression and mRNA self-induction of PDGF-B but did not alter the protein expression of PDGFR-beta. MPA strongly inhibited the PDGF-BB-induced mRNA expression of Egr-1 decreasing to 7.6 +/- 2.5% after 30 min (P

Tandem plasmapheresis and haemodialysis as a safe procedure in 82 patients with immune-mediated disease.

BACKGROUND: A number of medical, mostly immune-mediated conditions call for a combination therapy consisting of plasmapheresis and haemodialysis. While the two treatments are most commonly applied separately, we describe here the technical details of providing a combined 'tandem' treatment. Method. The components of a dialyzer (polysulfon membrane) and plasma filter are serially connected by a continuous arteriovenous haemofiltration (CAVH) system. In an extracorporeal circulation, using a blood pump the patient's blood is led first to the plasma filter and then into the dialyzer. The substituate connection is located behind the plasma filter and before the dialyzer. At the beginning it is obligatory to carry out an inspection of tubing system leakages. Afterwards, the system is flushed with a heparinized (5000 IE) sodium chloride solution that is removed thereafter. During the treatment, a blood flow of 150-200 ml/min is possible. In each case, the plasmafiltration and the ultrafiltration should not exceed 25% of the blood flow. The whole time, an intermittent check of blood pressure and heart rate is necessary. The total procedure does not take longer than a routine haemodialysis (3-4 h). RESULTS: In 82 patients we performed 483 tandem treatments during the last 16 years. None of the patients had volume disturbances caused by plasma shifts and derangements of electrolytes and acid-base balance were immediately equalized. There were no episodes of hypotension or bleeding. Back-filtration did not occur. CONCLUSION: Providing both haemodialysis and plasmapheresis at the same time reduces treatment time and thus, overall cost of the treatment. This retrospective analysis shows the tandem treatment to be safe and effective.

Influence of interleukin-6 G-174C gene polymorphism on coronary artery disease, cardiovascular complications and mortality in dialysis patients.

BACKGROUND: Inflammation is a well recognized central component of atherosclerotic processes in chronic kidney disease. Interleukin-6 (IL-6) levels are a strong determinant of cardiovascular mortality in dialysis patients. We evaluated the impact of IL-6 gene G-174C polymorphism associated with modified IL-6 production on the development of coronary artery disease (CAD), cardiovascular events and mortality in chronic dialysis patients. METHODS: We studied n = 463 patients on chronic dialysis with angiographically confirmed (n = 218) or excluded (n = 245) CAD followed up for 65 months after initiation of dialysis. Monitored were arterial hypertension, diabetes mellitus, hyperlipidemia, smoking, CRP and fibrinogen. IL-6 gene G-174C polymorphism was determined by PCR amplification. RESULTS: The CC genotype was associated with an impaired patient survival (p < 0.05) remaining an independent risk factor for death in multivariate analysis (HR for CC genotype: 3.58, CI: 1.41-9.07, p < 0.01). CC genotype carrying CAD patients suffered significant frequently cardiovascular events (revascularization, myocardial infarction, death) compared to GG/GC genotype carriers (85.2% vs. 66.5, p < 0.05). However, the IL-6 gene G-174C polymorphism was not related to the onset and development of CAD itself (ns) and the inflammation parameters CRP and fibrinogen did not differ between the genotypes under investigation (ns). CONCLUSIONS: Our results suggest that IL-6 gene G-174C polymorphism is associated with the incidence of cardiovascular events and mortality in chronic dialysis patients.

The homozygous leu variant of the factor XIII Val34Leu polymorphism as a risk factor for the manifestation of thrombotic microangiopathies.

The 34 Leu (100T) variant of the factor XIII Val34Leu (G100T-) polymorphism slows down fibrinolysis and has been proposed as a thrombotic risk factor. In this pilot study, we enrolled 40 patients (mean age +/- SD = 38 +/- 11 years) and 728 controls to assess the role of this genetic variant for the manifestation of thrombotic microangiopathies. From the genotype prevalences, an increased manifestation risk for carriers of the TT genotype (homozygous Leu variant) of the factor XIII Val34Leu (G100T-) polymorphism was calculated (odds ratio [OR] = 2.44; 95% confidence interval [CI] = 0.8-7.6; P = .11). This association was statistically significant for patients with thrombotic thrombocytopenic purpura-hemolytic-uremic syndrome (TTP-HUS) (OR = 6.6; 95% CI = 1.7-25.9; P = .006). Our data suggest a role of the homozygous Leu variant of the factor XIII Val34Leu polymorphism in the manifestation of thrombotic microangiopathies. Decreased fibrinolysis in the presence of this genetic variant provides a plausible explanation for this association.

Are prothrombotic variants of platelet glycoprotein receptor polymorphisms involved in the pathogenesis of thrombotic microangiopathies?

Thrombotic microangiopathies are life-threatening disorders characterized by vascular microthromboses, schistocytic hemolytic anemia, and thrombocytopenia. Although recent research has partially explained the pathogenesis of these rare entities, the determinants contributing to the onset and modulating the severity of thrombotic microangiopathies are largely unknown. The present study assessed the putative role of prothrombotic platelet receptor polymorphisms in thrombotic microangiopathies that have been found to be associated with premature onset of myocardial infarction in predisposed individuals. Thirty-four consecutive patients admitted with the diagnosis of thrombotic microangiopathy and 759 healthy subjects were enrolled. Genotyping of the human platelet antigen (HPA) 2 an the Kozak sequence polymorphism of GP Ibalpha of the platelets' von Willebrand factor receptor glycoprotein (GP) Ib-V-IX, the HPA-1 and the HPA-3 polymorphism of the fibrinogen receptor GP IIb-IIIa (integrin alpha(IIb)beta( 3)) and the HPA-5 and GP Ia 807 C/T polymorphism of the collagen receptor GP Ia-IIa (integrin alpha(2)beta(1)) were determined according to standard procedures. As a result, no significant differences in the prevalence of prothrombotic variants of platelet-receptor polymorphisms between patients and healthy control subjects were observed. However, although not significant, the prothrombotic bb genotype of the HPA-1 polymorphism was more prevalent in the patients. The findings do not provide evidence that platelet receptor polymorphisms are determinants for the onset of thrombotic microangiopathies or predispose to a more severe course. Along with this observation, screening for respective platelet-receptor polymorphisms does not appear to contribute to risk stratification of affected patients.

The TT genotype of the C677T polymorphism in the methylentetrahydrofolate reductase as a risk factor in thrombotic microangiopathies: results from a pilot study.

In this study, we assessed the potential role of the TT genotype of the gene of the methylenetetrahydrofolate reductase for the manifestation of thrombotic microangiopathies, enrolling 40 affected patients (mean age [+/- standard deviation] 35 +/- 11 years). As a result, the methylenetetrahydrofolate reductase 677TT genotype was more prevalent in patients with thrombotic microangiopathies compared with controls (adjusted odds ratio = 2.58, 95% confidence interval = 1.2-5.7, P = .018), particularly in those suffering from the hemolytic uremic syndrome. A hemolytic more severe clinical course of thrombotic microangiopathies in carriers of the methylenetetrahydrofolate reductase 677TT genotype was not observed. In summary, our findings suggest a significant influence of the methylenetetrahydrofolate reductase genotype on the manifestation of thrombotic microangiopathies. The 677 TT genotype of this polymorphism appears to be a risk factor for manifestation of these rare thrombotic disorders, possibly explained by endothelial activation and increased oxidative stress.

The G1691A mutation of the factor V gene (factor V Leiden) and the G20210A mutation of the prothrombin gene as risk factors in thrombotic microangiopathies.

Factor V Leiden (FVL) mutation and prothrombin G20210A mutation are common hereditary risk factors for venous thrombosis. In the current study, 40 patients (mean age +/- standard deviation, 35 +/- 11 years) and 764 healthy control subjects (mean age +/- standard deviation, 37 +/- 14 years) were enrolled to assess the potential role of these mutations in the manifestation of thrombotic microangiopathies. Compared with controls, neither the heterozygous FVL mutation (7.5% vs 8.5%; P = 1) nor the heterozygous prothrombin mutation (2.5% vs 2.8%; P = 1) was more prevalent in the patients. The findings do not support a significant role of FVL and prothrombin mutations as risk factors for the manifestation of thrombotic microangiopathies. Thus, screening for these mutations does not allow the identification of individuals at increased risk for these rare thrombotic disorders.

Influence of interleukin-10 gene G-1082A polymorphism on recurrent IgA nephropathy.

BACKGROUND: The G-1082A polymorphism of the interleukin-10 (IL-10) gene has been associated with modified gene expression and the progression of primary IgA nephropathy (IgAN). In the present study, we evaluated its influence on recurrent IgAN after renal transplantation. METHODS: We studied 103 patients who suffered from IgAN and underwent renal transplantation, followed up for 5.8 -/+ 3.4 years. A cohort of 206 matched renal allograft recipients with other primary diseases was analyzed as a control group. IL-10 gene G-1082A polymorphism was determined by PCR amplification. RESULTS: Microscopic hematuria and/or proteinuria of more than 500 mg/24 hours occurred in 22 patients (21%). Histological confirmation of IgAN recurrence was obtained in 16 patients. Young recipient age was associated with biopsy-proven IgAN recurrence in the Kaplan-Meier analysis of recurrence-free survival (p=0.05). The presence of IgAN recurrence had no impact on graft survival (not significant [NS]). Furthermore, graft survival was similar in patients with IgAN and patients with other primary diseases (NS). The IL-10 GG genotype was associated with a higher recurrence rate in the Kaplan-Meier analysis of recurrence-free survival (p<0.05). CONCLUSIONS: IgAN recurrence is a common complication, especially in younger renal transplant recipients. IL-10 gene G-1082A polymorphism was associated with an increased recurrence rate.

Influence of cytokine gene polymorphisms on IgA nephropathy.

Aims. Recently, polymorphisms of cytokine genes have been associated with altered gene expression and modified cytokine production. We evaluated the impact of TGF-beta1 gene Arg(25)-->Pro, TNFalpha gene G-308A and IL-6 gene G-174C polymorphisms on the clinical manifestations of IgA nephropathy. Patients and methods. The clinical course of 127 patients with biopsy-proven IgA nephropathy followed up for 6.6 +/- 6.0 years was studied. Patients were classified according to the slope of reciprocal serum creatinine into group A (slow progressors, n = 78) and group B (fast progressors, n = 49). TGF-beta1 gene Arg(25)-->Pro, TNFalpha gene G-308A and IL-6 gene G-174C polymorphisms were determined by PCR amplification followed by restriction digestion with the endonucleases Sau96 I, Nco I, and Lwe I respectively. Results. The genotype distribution of the investigated polymorphisms was similar in patients and control subjects (ns). Age, initial renal function, proteinuria, and blood pressure did not differ significantly between patients with different genotypes. The investigated polymorphisms were not associated with the progression of the IgA nephropathy, as shown by the similar genotype distribution in group A and group B (slow progressors: TGF-beta1, 92.3%; TNFalpha, 25.6%; IL-6, 74.4%; fast progressors: TGF-beta1, 85.7%; TNFalpha, 22.4%; IL-6: 81.6%, ns). Furthermore, these polymorphisms had no impact on renal survival in the Kaplan Meier analysis (ns). Conclusion. Our results suggest that TGF-beta1 gene Arg(25)-->Pro, TNFalpha gene G-308A, and IL-6 gene G-174C polymorphisms are not risk factors or markers of progression in Caucasian patients with IgA nephropathy.

Amyloidosis and bleeding: pathophysiology, diagnosis, and therapy.

Amyloid diseases can be associated with potentially life-threatening hemorrhage. Pathogenetic factors contributing to the abnormal bleeding tendency in this setting are heterogeneous and depend on the type of amyloidosis and pattern of organ involvement. In patients with light-chain (AL) amyloidosis, acquired hemostatic abnormalities, including coagulation factor deficiencies, hyperfibrinolysis, and platelet dysfunction, can be regarded as the most important pathogenetic factors. In patients with other types of amyloidosis, acquired hemostatic defects are rare, and amyloid deposition has also been reported to be the main cause of abnormal bleeding manifestations. Amyloid angiopathy with increased fragility of blood vessels and impaired vasoconstriction may promote bleeding in this setting. Rupture of solid organs caused by amyloid deposition also was reported. Whereas therapeutic options in bleeding caused by local amyloid deposition are restricted to supportive measures and, in severe cases, surgery, acquired hemostatic defects may be treated according to the causative mechanism. In this review, we focus on bleeding risks in patients with amyloid diseases. Current concepts with regard to pathophysiology, diagnosis, and treatment are summarized and discussed.

Hodgkin disease-like posttransplantation lymphoproliferative disorder of donor origin in a renal allograft recipient.

Posttransplantation lymphoproliferative disorder (PTLD) develops in 1.6% of renal allograft recipients. More than 90% are of recipient origin. There are only a few reports of Hodgkin disease-like PTLD in allograft patients. We report the case of a Hodgkin disease-like PTLD of donor origin in a 16-year-old renal allograft recipient. Fourteen months after transplantation, an increasing inhomogeneous structure in the hilar region of the transplanted kidney became apparent and was excised. Histological examination showed Hodgkin- and Sternberg-Reed-like cells. Immunostaining showed CD20-positive and CD15-negative cells and Epstein-Barr virus (EBV) involvement (EBV-encoded small nonpolyadenylated RNA and EBV-determined nuclear antigen 2). DNA fingerprinting analysis proved the lymphoma to be of donor origin. Treatment consisted of nephrectomy, discontinuation of immunosuppression therapy, and local radiation. Three years after lymphoma removal, the patient was still without relapse and underwent retransplantation with stable function of the second allograft for more than 2 years now.

Citrate plasma levels in patients under regional anticoagulation in continuous venovenous hemofiltration.

BACKGROUND: Different methods of regional anticoagulation using citrate in continuous hemofiltration have been described. To date, only such surrogate parameters as pH, anion gap, total calcium concentration, or total calcium-ionized calcium ratio have been proposed to reflect increased plasma citrate levels and thus risk for side effects. However, none of these parameters has been correlated with plasma citrate levels in critically ill patients. METHODS: Sixteen patients were treated with continuous venovenous hemofiltration (CVVH) and citrate anticoagulation for a mean of 13 +/- 9 days. Citrate levels were measured every other day, and correlations were calculated with the mentioned parameters. RESULTS: Steady-state citrate levels on treatment day 3 were 16.39 +/- 15.77 mg/dL (range, 2.63 to 73.49 mg/dL [853 +/- 821 micromol/L; range, 137 to 3825 micromol/L]). The highest correlation was found between citrate plasma level and total calcium-ionized calcium ratio (R = 0.85; P < 0.001). pH (R = -0.15) and anion gap (R = 0.36) were not helpful in estimating citrate plasma levels in patients treated with citrate-CVVH. CONCLUSION: Calculating total calcium-ionized calcium ratio is a simple tool that correlates best with citrate plasma levels. We recommend close monitoring of this parameter in all patients administered high doses of citrate as part of regional anticoagulation protocols.

Duplex ultrasound and renin ratio predict treatment failure after revascularization for renal artery stenosis.

BACKGROUND: The aim of this study was to find predictors to identify patients with hypertension who will not improve after removal of renal artery stenosis (RAS). METHODS: Prospective study of patients with unilateral stenosis (>60% diameter reduction) and hypertension in 24-h measurements despite antihypertensive drugs, who underwent revascularization (surgery/angioplasty). Examinations were performed before treatment and after 3 and 6 months after exclusion of restenosis. Studies included 24-h blood pressure, creatinine clearance, 99Tc MAG3 scintigraphy, and measurements of renal vein plasma renin activity (PRA). Intrarenal resistance indices (RI) were determined with duplex ultrasound before and 30 min after administration of intravenous enalaprilat. Improvement of hypertension was defined by a score consisting of 24-h mean arterial pressure and the number of antihypertensive drugs. RESULTS: From December 2000 to December 2003, 50 patients completed the study. Improvement of hypertension was observed in 18 patients (36%). Comparison between responders (n = 18) and nonresponders (n = 32) revealed significant differences only for RI and PRA measurements. The largest area under the curve in receiver-operating characteristic (ROC) analysis for prediction of no improvement of hypertension was found for RI (stenosis side), which was nearly identical for measurements before and after administration of angiotensin-converting enzyme (ACE) inhibitor. The highest sensitivities and specificities predicting which patients will not improve were found for RIs > or = 0.55. The highest univariate odds ratio (OR 44, confidence interval [CI] 4.8-404) was found for the parameters of RI > or = 0.55 and a renin ratio of <1:1.5. CONCLUSIONS: Resistance indices of the poststenotic kidney above 0.55 and a negative renin ratio can predict a poor outcome concerning arterial blood pressure response after restoration of renal blood flow for unilateral renal artery stenosis.

[Diagnosis, treatment, and prognosis of renal artery stenosis]. / Diagnostik, Therapie und Prognose von Nierenarterienstenosen.

With the increasing age of the population we must be prepared for a higher number of patients with renal artery occlusive disease. The clinical importance of renal artery stenosis is the induction of severe hypertension and renal dysfunction or even dialysis dependency. In this context it is of importance to realize that the presence of renal artery stenosis is not always responsible for hypertension and renal dysfunction in the individual patient and that only a stenosis > 60-70% diameter reduction can be considered hemodynamically significant. Typical clinical symptoms are helpful to select patients for further screening methods. In this setting a prominent role of color duplex sonography is seen. Nevertheless, intraarterial angiography remains the gold standard. All treatment options (surgery, angioplasty and medical treatment alone) have specific advantages and disadvantages which should be considered in the individual case and must be reconsidered during follow-up. Independent of the treatment chosen, control of all cardiovascular risk factors needs consideration. The selection for invasive treatment requires a careful assessment of the hemodynamic significance of the stenosis, the presence of irreversible parenchymatous damage and the clarification of the treatment goals in the patient. The practical challenge for the clinician is to carefully consider the benefit and the risks associated with the various types of treatment and to select the best treatment for the individual patient.

Value of diabetes as an independent predictor of death in subjects with end-stage renal disease.

BACKGROUND AND PURPOSE: Diabetic subjects on hemodialysis have a poor survival. The authors performed a Kaplan-Meier survival analysis of diabetic versus nondiabetic subjects and investigated the value of diabetes as an independent predictor of death in these end-stage renal disease (ESRD) subjects. PATIENTS AND METHODS: From 1997 to 2003, 135 ESRD subjects (41 diabetics) were enrolled in a survival study beginning at the start of dialysis. Inclusion criterion was onset of dialysis at least 6 months before study entry. Exclusion criteria comprised age < 45 years, coronary artery disease (CAD), critical limb ischemia (CLI), or malignancies at ESRD onset up to 6 months after study entry. Subjects with clinical signs of vascular disease were followed up by coronary or peripheral angiographies. RESULTS: Baseline risk factors were similar between diabetic and nondiabetic subjects. The 5-year survival rate in nondiabetic subjects was 76.9% (95% confidence interval [CI] = 62-86%) versus 76.4% (95% CI = 53-89%) in diabetic patients (p = 0.402). Consistent with this finding, the Cox proportional hazards model revealed that diabetes does not significantly change the risk of death in ESRD subjects. De novo CAD developed in 35 and CLI in ten subjects, but both diseases were present more frequently in nonsurvivors (42% vs. 23%; p = 0.052) versus survivors (21% vs. 5%; p = 0.005). CONCLUSION: Diabetes is not an independent predictor of death in the ESRD study group presented here. Prevention of CAD and CLI in diabetic subjects is most important to improve survival.

Effects of candesartan on glomerular hemodynamics and permselectivity in patients with favorable renal allograft function.

BACKGROUND: Distinct effects of angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers on glomerular perfusion and permselectivity are important determinants of the substances nephroprotective quality. In renal allograft recipients, however, specific effects of angiotensin antagonism on glomerular function have not been evaluated so far. METHODS: Twenty patients with favorable allograft function were included into a prospective study within the first year after renal transplantation. Glomerular filtration rate, renal plasma flow, albuminuria, and the fractional clearances of neutral dextrans were determined at baseline and after 3 months of treatment with candesartan. Ten individuals after renal donation served as controls for the baseline evaluation. RESULTS: Compared with the control group, the allograft recipients had a higher renal-vascular resistance and a lower glomerular filtration rate. Albuminuria was significantly higher; however, the difference in the dextran sieving curve was not statistically significant. Apart from mild changes in biochemical parameters, the therapy with candesartan led to a rise in serum creatinine along with a nonsignificant drop in the glomerular filtration rate. There was a highly significant drop in filtration fraction and albuminuria. Glomerular permselectivity clearly improved for a range of dextran molecular diameters from 43 Angstrom up to 73 Angstrom. CONCLUSION: A therapy with candesartan has distinct effects on glomerular function in patients after renal transplantation. A drop in filtration fraction along with an improvement in glomerular permselectivity and albuminuria point to a nephroprotective quality that should lead to a systematic clinical evaluation of candesartan even in patients with favorable renal allograft function.

Different effect of cyclosporine A and mycophenolate mofetil on passive Heymann nephritis in the rat.

BACKGROUND: While cyclosporine A (CsA) is an effective therapy for nephrotic syndrome, it has nephrotoxic side effects. We compared the anti-proteinuric effects and nephrotoxicity in rats with passive Heymann nephritis (PHN) of CsA and mycophenolate mofetil (MMF). METHODS: PHN was induced in female Wistar rats. Two treatment groups consisting of 8 rats each received either 25 mg of CsA or 25 mg of MMF/kg body weight/day and were compared with untreated controls. Kidney function and proteinuria were monitored over 4 weeks. Western blots were used for densitometric analysis of renal cyclooxygenase-2 (COX-2) protein expression. Thromboxane B2 (TxB2) and 6-keto-PGF(1alpha) were determined by radioimmunoassays (RIAs) in renal tissue and urine. RESULTS: Rats with PHN exhibited a marked proteinuria of 12.76 +/- 4.42 vs. 0.73 +/- 0.28 mg/24 h (p < 0.01) and showed increased glomerular concentrations of TxB2 and 6-keto-PGF(1alpha) (992.6 +/- 216.9 and 1,187.0 +/- 54.2 pg/mg protein, respectively) compared with healthy controls (595 +/- 196.17 and 729 +/- 297.84, respectively) and a strongly induced COX-2 protein expression. CsA and MMF treatment reduced PHN-related proteinuria to 2.10 +/- 1.47 and 1.47 +/- 7.2 mg/24 h, respectively. In rats with PHN, CsA induced a significant deterioration of renal function and enhanced urine excretion of thromboxane A2, paralleled by a significant, twofold increase in COX-2 protein expression and renal prostaglandins. By contrast, MMF treatment in rats with PHN was not nephrotoxic and had no effect on prostaglandin production. COX-2 protein expression under MMF was suppressed. CONCLUSION: While the antiproteinuric efficacy of MMF and CsA in PHN was comparable, the absence of nephrotoxicity might favor MMF in the treatment of nephrotic syndrome. The CsA-induced increase in COX-2 expression and COX-2-dependent prostacyclin may indicate a mechanism that compensates nephrotoxicity in the diseased and CsA-exposed kidney.

Influence of beta3 integrin gene Leu/Pro33 polymorphism on primary glomerulonephritis.

BACKGROUND: Beta3 integrin subunit is expressed as alpha(IIb)beta3 integrin on platelets and as alpha(v)beta3 integrin on a variety of cells including renal endothelial, mesangial and tubular cells. Leu33/Pro33 polymorphism of beta3 integrin has been associated with altered platelet functions, cardiovascular complications and the incidence of acute rejection episodes in renal transplantation. We investigated its influence on IgA nephropathy (IgAN), focal segmental glomerulosclerosis (FSGS) and membranous glomerulonephritis (MGN). METHODS: We studied 251 patients with biopsy-proven primary glomerulonephritis (IgAN n = 127, FSGS n = 71, MGN n = 53) followed up for 6.3 +/- 5.3 years and 100 control subjects. Patients were classified according to the slope of reciprocal serum creatinine into slow (n = 162) and fast progressors (n = 89). Leu33/Pro33 polymorphism was determined by PCR amplification followed by restriction with the endonuclease Bcnl. RESULTS: The genotype frequencies were similar in patients and controls (n.s.). Initial renal function, proteinuria and blood pressure did not differ significantly between patients with different genotypes (n.s.). The genotype frequencies were similar in slow and fast progressors (n.s.). Furthermore, Leu33/Pro33 polymorphism had no impact on renal survival in the Kaplan-Meier analysis (n.s.). CONCLUSION: Our results indicate that beta3 integrin Leu33/Pro33 polymorphism is not a risk factor or a marker of progression in primary glomerulonephritis.