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B K Krämer

Publications and source records attributed to B K Krämer.

At least 19 recordsLinked to original sources
PubMed2006

Mini-incision for strictly retroperitoneal nephrectomy in living kidney donation vs flank incision.

BACKGROUND: Mini-incision donor nephrectomies (MIDNs) were established during the last decade, as an alternative to traditional open donor nephrectomy (ODN) via flank incision. In this study, we investigated intra-operative and post-operative data on outcome following MIDN in comparison with ODN data. METHODS: Data of 70 living kidney donations, performed at the University of Regensburg Medical Center since 1996, were evaluated. Donor operation was performed as either strictly retroperitoneal MIDN (n = 34) or as traditional ODN (n = 36) via flank incision. Total operation time, warm ischaemia time (WIT), perioperative pain-medication usage and creatinine levels as well as length of hospital stay, return to complete enteral nutrition and regular digestion were evaluated retrospectively. RESULTS: Total operation times were similar in MIDN, n = 34 (132 +/- 26 min) and in ODN, n = 36 (140 +/- 37 min) (P = 0.424). WIT was also similar in both: MIDN (0.9 +/- 0.4 min) and ODN (0.9 +/- 0.4 min) (P = 0.568). The requirement for post-operative opioids in morphine equivalent doses was significantly lower in MIDN (8.4 +/- 16 mg) compared with ODN (44 +/- 57 mg) (P = 0.001). Additional application of non-opioids (metamizole) (MIDN: 4.8 +/- 6.3 g, ODN: 3.4 +/- 3.9 g) and non-steroidal antirheumatic (NSAR) (diclofenac) (MIDN: 322 +/- 361 mg, ODN: 247 +/- 474 mg) revealed no significant differences between the groups. The hospital stay was 4.9 +/- 1.4 days in MIDN which was significantly shorter than that in ODN (9.3 +/- 3.3 days) (P = 0.001). Patients achieved fully independent mobility earlier in MIDN than in ODN (P = 0.934). Start of enteral nutrition with fluids was significantly quicker in MIDN (1.9 +/- 7 h) compared with ODN (12 +/- 13 h) (P = 0.05). Full enteral nutrition was accomplished significantly earlier in MIDN (1.6 +/- 0.8 days) (P = 0.023). Return to normal digestion revealed no significant differences between groups. Serum creatinine levels of all kidney donors were in the normal range (66 +/- 18 micromol/l) one day before nephrectomy, increased on day 1 after surgery (119 micromol/l +/- 31 micromol/l) and were stable on day 3 (115 micromol/l +/- 30 micromol/l) without significant differences. CONCLUSION: Strictly, retroperitoneal MIDN in living kidney donation is a fast and safe method for the procurement of a living donor graft, giving the patient a significantly shorter period of recovery, and thus is an attractive and recommendable alternative to traditional ODN procedures.

Adult↗
PubMed2006

Pretransplant calcium levels have no predictive value for delayed graft function, long-term graft function, cardiovascular events, or graft and patient survival in renal transplantation.

BACKGROUND: Disorders of calcium homeostasis are one of the most common problems in patients with end-stage renal disease (ESRD). Elevated calcium levels increase the incidence of cardiovascular mortality in ESRD patients, and appear to be a risk factor for the occurrence of delayed graft function (DGF) after kidney transplantation. Therefore, we investigated the impact of pretransplant serum calcium levels on outcomes after kidney transplantation: DGF, acute rejection, graft function, and survival, as well as the incidence of cardiovascular events. METHODS: We studied 285 patients (96.9% of all transplanted patients) who underwent their first transplantation between 1995 and 2004. Demographic data were extracted from hospital records or were documented during follow-up; serum samples were collected at the time of transplantation. RESULTS: In our cohort the incidence of DGF was 16.5% and 35.4% of acute rejection episodes (ARE). However, pretransplant calcium levels were not related to DGF or ARE in our patient cohort. Furthermore, there was no correlation between pretransplant serum calcium level with the incidence of cardiovascular events or mortality, as well as graft function or survival. CONCLUSION: In our study population pretransplant calcium levels showed no effect on DGF, ARE rate, the occurrence of cardiovascular events or death, renal graft function, or survival. Therefore, pretransplant calcium level is not a helpful marker for risk stratification at the time of transplantation.

Biomarkers↗
PubMed2006

Conversion from calcineurin inhibitors to sirolimus in patients with chronic renal allograft dysfunction.

BACKGROUND: Chronic renal transplant dysfunction in part may be due to the nephrotoxic effects of calcineurin inhibitors, which are still the mainstay of immunosuppressive therapy. Sirolimus, a new immunosuppressive compound devoid of significant nephrotoxicity, might therefore exhibit beneficial effects when used in renal transplant recipients with graft dysfunction. METHODS: Twelve renal transplant recipients included in this study had all been receiving calcineurin inhibitors for more than 12 months, and were free of rejection for more than 12 months. However, they demonstrated moderate renal dysfunction with serum creatinine values ranging from 1.8 to 4.0 mg/dL (164 to 351 micromol/L). After reaching a sirolimus level of 10 to 20 ng/mL, calcineurin inhibitor therapy was withheld. RESULTS: One month after initiation of sirolimus therapy, all patients were off calcineurin inhibitors. The average daily sirolimus dosage was 5.8+/-3.4 mg. No acute rejection episode and no graft failure was observed. No patient required hemodialysis or admission to the hospital. Calculated creatinine clearance increased from 63.4+/-9.9 to 69.2+/-9.7 mL/min (P=.0368) and serum bicarbonate increased from 20.8+/-3.17 to 22.5+/-3.7 meq/L (P=.001). Serum cholesterol increased from 180+/-26.5 to 239+/-28.8 mg/dL (4.65+/-0.69 to 6.18+/-0.74 mmol/L, P<.001), triglycerides increased from 155+/-53 to 289+/-123 mg/dL (1.75+/-0.6 to 3.26+/-1.39 mmol/L) and low-density lipoprotein cholesterol increased from 99+/-32 to 131+/-25.1 mg/dL (2.56+/-0.83 to 3.39+/-0.65 mmol/L, P=.01). Arterial blood pressure remained well controlled (126+/-15.6/74+/-8.9 vs 134+/-16.8/83+/-9.7). CONCLUSION: Conversion from calcineurin inhibitor therapy to sirolimus in patients more than 1 year after transplantation with impaired organ function is feasible, safe, and associated with a trend toward improved renal function.

Adult↗
PubMed2006

Reverse diastolic intrarenal flow due to calcineurin inhibitor (CNI) toxicity.

Renal calcineurin inhibitor (CNI) toxicity is a frequent side effect of immunosuppression with CNIs in solid organ transplantation, leading to acute and chronic renal failure. Acute CNI toxicity is due to vasoconstriction of the vasa afferens and efferens and vacuolization of smooth muscle cells with medial hyalinosis, leading to vessel lumen narrowing. Our case had an acute renal failure 8 months after deceased donor kidney transplantation under treatment with tacrolimus, sirolimus and prednisolone. In Doppler sonography, we observed reverse diastolic intrarenal blood flow, reflecting intense vessel narrowing. There were histological signs of acute CNI toxicity. Within days of reducing the tacrolimus trough level, renal function improved markedly and Doppler sonography showed orthograde intrarenal blood flow. This is the first case of functional, Doppler sonographic evidence for CNI-induced, rapidly reversible narrowing of intrarenal vessels. This case illustrates the potential role of tacrolimus and sirolimus dosing in combination therapy to produce severe intrarenal vasoconstriction.

Biopsy↗
PubMed2006

Exanthema and acute anuric renal failure.

A 15-year-old girl with a history of Kawasaki disease was admitted to our nephrological department due to acute renal failure. Despite antibiotic therapy because of fever and the symptoms of a pharyngitis in the last few days, the girl showed persisting fever and developed arthralgias, an exanthema and a rising serum creatinine as well as anuria. A wide variety of differential diagnoses has to be thought of because of the history of the Kawasaki disease (symptoms like fever, pharyngitis, exanthema and arthralgia), i.e. hemolytic-uremic syndrome, vasculitis, ascending infection, postinfection glomerulonephritis. In consideration of etiologically unclear "rapidly progressive renal failure" with anuria and thrombocytopenia an immediate renal biopsy was done and revealed a severe drug induced acute interstitial nephritis. Due to this diagnosis we treated the patient with corticosteroids. Within 4 weeks serum creatinine declined to 1.8 mg/dl but did not normalize.

Acute Kidney Injury↗
PubMed2006

Effect of ACE and AT-2 inhibitors on mortality and progression to microalbuminuria in a nested case-control study of diabetic nephropathy in diabetes mellitus type 2: results from the GENDIAN study.

INTRODUCTION: There is an established role of clinical risk factors such as arterial hypertension and smoking in causing cardiovascular morbidity and diabetic nephropathy (DNP). Genetic factors increase the risk for DNP. To examine the genetic risk, we initiated a case-control study with predefined follow-up examinations. We describe the study design and baseline characteristics under special consideration of comedication, and give preliminary results of the 4-year follow-up. METHODS: We enrolled all 477 patients with DNP receiving maintenance hemodialysis in 30 centers in Southern Germany between August 1999 and January 2000. As controls, we enrolled all 482 diabetes mellitus type 2 patients without urinary microalbuminuria in two examinations on consecutive days and without other signs of renal disease in a large diabetes clinic from September 2000 to September 2001. Follow-up examinations are performed 4 and 6 years after inclusion by questionnaire and telephone interview to determine mortality and new morbidity. Controls progressing to novel DNP at follow-up, as defined by semiquantitative dipstick urinary albumin/creatinine ratio > 30 mg/g, are defined as cases in the study's nested case control component. RESULTS: At study inclusion in cases and controls, respectively, mean age was 67.3 +/- 8.2 and 58.1 +/- 11.2 years and duration of diabetes mellitus was 15.6 +/- 9.6 (at dialysis initiation) and 11.0 +/- 8.6 years. 328 controls (of which 25 had died and 14 did not perform urinalysis) were subjected to follow-up at 4 years, at a mean of 3.5 +/- 0.8 years after inclusion. 51.2% (n = 148) of living controls remained normalbuminuric, 33.9% (n = 98) had microor macroalbuminuria, and in 14.9% (n = 43) the dipstick test was inconclusive. There was no significant difference in progression to micro- or macroalbuminuria between controls treated with ACE or AT-2 inhibitors at baseline or not. Renal function as estimated by the abbreviated MDRD formula declined from 86.8 +/- 21.0 to 82.5 +/- 22.3 ml/min/1.73 m2 (p < 0.001). The decline was significant in patients on ACE or AT-2 inhibitors at baseline and not in patients without such medication at baseline. DISCUSSION: GENDIAN is a large case-control study designed to evaluate clinical and genetic determinants of DNP and other complications of long-standing diabetes mellitus type 2. We observed an association of ACE or AT-2 inhibitor therapy with cardiovascular comorbidity and a significant decline in renal function after a 4-year follow-up.

Age Factors↗
PubMed2006

Increase in renal vascular resistance after intake of cyclosporin A and tacrolimus and reversal by nitroglycerin spray: a study in patients with stable renal allograft function.

PURPOSE: Acute effects of drug administration on renal arterial resistance index (RI) are still discussed controversially. In our study we investigated the immediate effects of cyclosporin A (CyA) and tacrolimus (FK-506) on renal arterial resistance indices in patients with stable graft function after renal transplantation. Additionally we studied the effects of nitroglycerin spray on resistance indices. METHODS: RI was measured by color Doppler sonography at baseline, at 1 and 2 hours after intake of medication and 30 minutes after administration of nitroglycerin spray which followed the 2-hour measurement. 34 renal transplant recipients were examined. 16 patients received CyA, 18 patients received FK-506. Whole blood levels of calcineurin inhibitors were taken at each time point. Arterial blood pressure and heart rate were measured to assess possible systemic hemodynamic effects. RESULTS: Mean RI values increased significantly in both groups 1 hour after calcineurin inhibitor intake and remained still significantly elevated after 2 hours. There was no significant increase of mean arterial blood pressure nor was there any correlation between whole blood levels of calcineurin inhibitors and mean RI. 30 minutes after administration of nitroglycerin spray, mean RI values decreased significantly to a level even below baseline. Mean arterial blood pressure also decreased after administration of nitroglycerin. CONCLUSION: Renal RI values are markedly influenced by a recent intake of calcineurin inhibitors and vasoactive substances such as nitrates. This demonstrates the necessity of keeping standardized conditions when using RI as a tool in followup investigations after renal transplantation.

Adult↗
PubMed2005

Renal effects of gadopentetate dimeglumine in patients with normal and impaired renal function.

Gadolinium chelates are widely used in magnetic resonance imaging as contrast medium in patients with nephropathy. However, only few studies have investigated the effect of gadolinium on serum creatinine concentration and estimated GFR as surrogate markers of renal function. This study was performed to evaluate the effect of gadopentetate dimeglumine in a dose sufficient for diagnostic and interventional purposes on renal function in a large sample of patients. We analyzed serum creatinine and serum-urea levels before and after the administration of gadopentetate dimeglumine in patients with normal and patients with pre-existing impaired renal function. Age, height, body mass, sex, medication and preexisting illnesses such as diabetes, renal artery stenosis and heart disease were monitored. In 181 patients with normal renal function, there was no statistically significant change in serum creatinine concentration after the administration of gadopentetate dimeglumine (at baseline: 0.72 +/- 0.18 mg/dl, after gadolinium: 0.73 +/- 0.22 mg/dl). In contrary, serum creatinine levels decreased significantly after the administration of gadolinium in 198 patients with pre-existing renal impairment (1.82 +/- 1.03 mg/dl before and 1.72 +/- 1.03 mg/dl after gadolinium) (p < 0.01). According to this surrogate marker of renal function, the change of estimated GFR in patients with normal baseline renal function was not significant, while in patients with impaired renal function, GFR increased after the administration of gadolinium (p < 0.001). The high diagnostic value of gadolinium contrast media is associated with a very small risk of adverse reactions. Our findings show that the administration of gadolinium even is associated with a decrease of serum creatinine in patients with pre-existing renal impairment. In conclusion, the use of gadolinium-based contrast media may be considered as a safe alternative in patients with impaired renal function for whom use of iodine-based contrast agents is prone to a high rate of radiocontrast-induced nephropathy.

Contrast Media↗
PubMed2005

Effect of HMG-CoA-reductase inhibitors on survival in type 2 diabetes patients with end stage diabetic nephropathy.

INTRODUCTION: We studied the effect of HMG-CoA-reductase inhibitor (= CSE-I) treatment on mortality in a population of hemodialysis patients with diabetic nephropathy due to type 2 diabetes. Since the efficacy of CSE-I in dialysis patients is discussed controversially, we tested the hypothesis that only patients with LDL-cholesterol > 100 mg/dl benefit from CSE-I. METHODS: We enrolled all 445 prevalent chronic hemodialysis patients with end-stage diabetic nephropathy from 30 centres in Southern Germany from August 1999 to January 2000 for prospective study until December 2003. Fasting lipid profiles prior to dialysis session and a complete clinical phenotype were determined at inclusion. We formed 2 patient groups (serum LDL > vs. < or = 100 mg/dl). Only CSE-I were used as lipid lowering therapy in our cohort. 122 Patients were on CSE-I therapy during the study. All cause mortality (ACM) was the primary end point. Survival analysis was performed by Kaplan Meier and multivariate Cox regression analysis. RESULTS: Multivariate regression analysis and Kaplan Meier survival analysis showed a decrease in risk for ACM for patients on CSE-I therapy, irrespective of lipid status (multivariate hazard ratio (= HR) 0.58; p = 0.049; ACM 72.1% (no CSE-I) vs. 59.7% (+ CSE-I); mean survival 2.37 +/- 0.08 years (no CSE-I) vs. 2.77 +/- 0.12 years (+ CSE-I), p = 0.003). In patients with LDL > 100 mg/dl, statin treatment was also associated with reduced ACM: 48.0% (+ CSE-I) vs. 70.1% (no CSE-I), (multivariate HR 0.28, CI 95% 0.11 - 0.75, p = 0.01), but not in patients with LDL < or = 100 mg/dl (HR 0.84, CI 95% 0.41 - 1.72 p = 0.63). CONCLUSION: Our data indicates that hemodialysis patients with type 2 diabetic nephropathy may benefit from statin therapy irrespective of baseline LDL-cholesterol level. Patients with LDL > 100 mg/dl benefit most when treated with CSE-I.

Aged↗
PubMed2005

Effect of genetic variation on therapy with angiotensin converting enzyme inhibitors or angiotensin receptor blockers in dialysis patients.

INTRODUCTION: The role of interaction of polymorphisms in the Renin-Angiotensin-System (RAS) with angiotensin converting enzyme (ACE) or angiotensin receptor (AGTR1) inhibitors (RAS inhibitors) is unknown, as is the role of such therapy in end stage renal disease (ESRD) patients. METHODS: We enrolled all 445 prevalent patients with diabetic nephropathy receiving maintenance hemodialysis in 30 centers in Southern Germany from August 1999 to January 2000 for prospective survival analysis until December 2003. Blood pressure and medication was recorded at inclusion. We determined survival specific for allelic variants of the ACE (insertion/deletion), Angiotensinogen (M235T) and AGTR1 (A1166C) genes. The effect of therapy with RAS inhibitors at study inclusion was determined for the allelic variants of each gene. The primary end point was all cause mortality (ACM). RESULTS: For all polymorphisms, and for therapy with RAS inhibitors there was no significant effect on survival in the complete collective (n = 445), though there was an insignificant trend for improved survival in patients on AGTR1 antagonists. Increased ACM risk was associated with treatment with RAS inhibitors only in patients homozygous for the wild type AGTR1 1166A allele (HR 1.65, p = 0.01). For all other polymorphisms, therapy with RAS inhibitors had no significant effect on ACM, irrespective of genotype. Similar results were obtained in patients with systolic ventricular dysfunction. CONCLUSION: Our data do not show a survival advantage for type 2 diabetes hemodialysis patients receiving RAS inhibiting therapy. In addition, our data indicate that allelic variation in RAS genes and pharmacogenetic interaction with RAS inhibition does not affect mortality risk in diabetic hemodialysis patients.

Aged↗
PubMed2005

[Treatment and prophylaxis of recurrent urinary tract infections].

Recurrent urinary tract infections are typical diseases of sexually active young women. Only elder women show significant rates of underlying, mostly urological diseases. Besides behavioral changes long-term antimicrobial therapy is still the mainstay of both prophylaxis and therapy. This report provides information on the etiology for recurrent urinary tract infections. Strategies for prevention are illustrated. The actual significances of organic remedies and antibiotics respectively are discussed; ineffective therapies are identified. Furthermore an outlook is given on promising novel therapeutics, i.e. vaccines which are already tested in clinical trials.

Anti-Bacterial Agents↗
PubMed2005

Graft function, cardiovascular risk factors, and sex hormones in renal transplant recipients on an immunosuppressive regimen of everolimus, reduced dose of cyclosporine, and basiliximab.

A prospective, randomized trial evaluated the combination of everolimus of 1.5 or 3 mg/d with steroids, basiliximab, and low-dose cyclosporine (CsA) adjusted by C2 monitoring in 256 renal transplant recipients. CsA C2 target levels, initially set at 600 ng/mL, were tapered over time posttransplant. The median serum creatinine concentrations were 130 mumol/L in both sirolimus groups (1.5 and 3 mg/d) at 6 months. Biopsy-proven acute rejection (BPAR) occurred in 13.7% and 15.1% of patients in the 1.5 and 3 mg/d groups, respectively. The incidence of BPAR was significantly higher among patients with everolimus trough levels < 3 ng/mL. Posttransplant diabetes mellitus occurred rarely, and blood pressure control appeared favorable; however, serum cholesterol levels were increased by approximately 50%, and serum triglycerides by approximately 100%. Serum testosterone concentrations increased after renal transplantation in both everolimus groups. Concentration-controlled everolimus therapy combined with low-dose CsA provides effective protection against rejection with good renal function and safety profiles.

Antibodies, Monoclonal↗
PubMed2005

Steroid withdrawal or steroid avoidance in renal transplant recipients: focus on tacrolimus-based immunosuppressive regimens.

Steroid-induced adverse effects after transplantation include cosmetic, metabolic, and cardiovascular complications. Steroid withdrawal or avoidance with cyclosporine-based regimens have been hampered by an unacceptably high rate of acute rejections and increased rates of graft loss. Recently the results of several large, randomized trials of steroid withdrawal/avoidance with tacrolimus-based immunosuppression in renal transplant recipients became available. A review of these trials appeared to be of clinical interest. Data from the THOMAS trial clearly indicate that steroid withdrawal from a regimen of tacrolimus, mycophenolate mofetil (MMF), steroids after 3 months after transplantation is safe with regard to acute rejection rate and graft survival. If an induction therapy with daclizumab is used in combination with tacrolimus and MMF (CARMEN trial), even steroid avoidance is safe with regard to acute rejection rate and graft survival. Finally, in the ATLAS trial, steroid avoidance with basiliximab in combination with tacrolimus (resulting in tacrolimus monotherapy) or alternatively with tacrolimus and MMF both resulted in similar graft survival, but higher rates of acute rejection. In conclusion, steroid withdrawal is safe from a triple-drug regimen of tacrolimus, MMF, and steroids after 3 months after transplantation, and steroid use may completely be avoided with tacrolimus, and MMF combined with daclizumab induction. Tacrolimus monotherapy may be achieved using basiliximab induction at the price of higher rates of acute rejection, but with unaffected graft survival. Thus tacrolimus-based immunosuppression with or without interleukin-2 receptor antagonist induction has made steroid withdrawal or avoidance a realistic option in renal transplantation.

Drug Therapy, Combination↗
PubMed2005

Cardiovascular risk estimates and risk factors in renal transplant recipients.

Cardiovascular morbidity, including coronary artery disease and left ventricular hypertrophy, and mortality are high in patients following renal transplantation. Cardiovascular disease is thought to be due to traditional (hypertension, hyperlipidemia, diabetes mellitus and smoking) as well as nontraditional cardiovascular risk factors (microinflammation). Furthermore, immunosuppressive drugs, namely, calcineurin inhibitors, sirolimus, and steroids, have been reported to adversely affect cardiovascular risk factors (e.g., hypertension, hyperlipidemia, hyperglycemia). Evidence from comparative trials and from conversion studies suggest that blood pressure, hyperlipidemia, and hyperglycemia after renal transplantation may be differentially affected by the calcineurin inhibitors cyclosporine and tacrolimus. In the European Tacrolimus versus Cyclosporin A Microemulsion Renal Transplantation Study, 557 patients were randomly allocated to therapy with tacrolimus (n = 286) versus cyclosporine (n = 271). In addition, to blood pressure, serum cholesterol, HDL cholesterol, triglycerides, and blood glucose, we estimated the 10-year risk of coronary heart disease (Framingham risk score). Tacrolimus resulted in a significantly lower time-weighted average of serum cholesterol (P < .001), and mean arterial blood pressure (P < .05), but a higher time-weighted average of blood glucose (P < .01) than cyclosporine. Mean 10-year coronary artery disease risk estimate was significantly lower in men treated with tacrolimus, (10.0% versus 13.2%; P < .01) but was unchanged in women (4.7% versus 7.0%). Tacrolimus and cyclosporine microemulsion have compound-specific effects on cardiovascular risk factors that differentially affect the predicted rate of coronary artery disease.

Cardiovascular Diseases↗
PubMed2004

Quantitative gene expression analysis of fractalkine using laser microdissection in biopsies from kidney allografts with acute rejection.

Percutaneous biopsy of the kidney remains the gold standard to establish a diagnosis in renal diseases. Only semiquantitative assessments of gene expression on biopsies have been possible so far. We studied gene expression of the chemokine fractalkine (FKN) in 12 biopsies from laser microdissected kidney allografts that showed histologic signs of acute rejection and 10 controls. As quantified by real-time PCR, the relative tubular FKN expression increased from 1.0 [0.81 to 2.95] (median [range]) in controls to 12.44 [0.90 to 191.0] in acute rejection (P < .01); glomerular FKN expression from 1.3 [0.07 to 27.44] to 12.22 [1.32 to 50.23] (P < .05); and vascular expression, from 0.72 [0.37 to 5.11] to 7.07 [1.19 to 73.49] (P < .01). Furthermore, there was a trend toward higher glomerular FKN expression among patients with more severe rejection. Our results suggest a role of FKN in acute renal allograft rejection.

Acute Disease↗