Volume 62, No. 1/2004(July)
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 Clinical Nephrology
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Originals
What is the best hydration
regimen to prevent contrast media-induced nephrotoxicity?
Abstract
B.D. Bader, E.D. Berger, M.B. Heede, I. Silberbaur, S. Duda, T. Risler and C.M. Erley
1Department of Internal Medicine III, Section of Nephrology and Hypertension, and 2Department of Radiology, University of Tübingen, Tübingen, Germany
Background: Hydration is a commonly used method to prevent the decline in GFR after contrast media (CM) application. So far, there have been no controlled, randomized trials investigating the most effective route of fluid administration. Methods: Thirty-nine patients with normal renal function (65 ± 9 years, serum creatinine 0.9 ± 0.2 mg/dl, GFR = 110 ± 31 ml/min/1.73 m2) receiving at least 80 ml of low-osmolality CM during an angiographic procedure were randomized to one of the following hydration regimens: Group 1: volume expansion with 300 ml saline during CM administration (n = 20, serum creatinine 0.8 ± 0.1 mg/dl , GFR 119 ± 27 ml/min/1.73 m2); Group 2: intravenous administration of at least 2,000 ml saline within 12 h before and after CM application (n = 19, serum creatinine 0.9 ± 0.2 mg/dl, GFR 101 ± 32 ml/min/1.73 m2). GFR was measured by CM clearance (Renalyzer) at baseline and 48 hours after CM administration. The primary end point was the mean change in the GFR after 48 hours, the secondary one was the incidence of CM-induced nephropathy (CMIN), defined as a decrease in GFR of more than 50% from the baseline GFR within 48 hours. Results: Patients of group 1 showed a significantly (p < 0.05) higher decline in GFR (D GFR 34.6 ± 25.7 ml/min/1.73 m2) compared to patients receiving the intravenous prehydration regimen (D GFR 18.3 ± 25.0 ml/min/1.73 m2). The incidence of CMIN was lower in prehydrated patients (5.3%) compared to the other group (15%). Conclusion: In patients with normal renal function, intravenous prehydration seems to be a very effective and feasible method to prevent the decline in GFR after contrast media exposure. Volume expansion given only during the CM exposure appears not to be sufficient enough to prevent renal damage.Correspondence to:
Dr. C.M. Erley
University of Tübingen
Department of Medicine III, Section of Nephrology and Hypertension
Otfried-Müller-Straße 10
D-72076 Tübingen, Germany
Email: christiane.erley@med.uni-tuebingen.de
Originals
Benign prostatic hyperplasia (BPH) requiring transurethral resection in freshly transplanted renal allograft
recipients
Abstract
M.J. Koziolek1, M. Wolfram3, G.A. Müller1, A.K. Scheel1, F. Strutz1, E.H. Scheuermann3 and W. Kramer3
1Department of Nephrology and Rheumatology, Georg August University, Göttingen, 2Department of Urology, and 3Department of Nephrology, Medical Clinic IV, J.W. Goethe University, Frankfurt/Main, Germany
With recent progress in surgery and immunosuppression, more and more older men receive a kidney transplant. Thus, it is likely that the incidence of BPH in male transplant recipients is growing in parallel with age. Nonetheless, no data exist about diagnostic parameters for BPH in freshly transplanted male kidney allograft recipients. We evaluated whether established diagnostic and therapeutic criteria for BPH are valid for the evaluation of renal transplant recipients. BPH was diagnosed in 8 of 11 recipients older than 55 years. In all freshly transplanted renal allograft recipients, lower urinary tract symptoms (LUTS) were detected using an international prostate symptoms score (IPSS). This score was 9.6 ± 7.1 in patients without BPH, and significantly higher with 21.1 ± 4.3 in patients with BPH. In receiver-operating characteristics (ROC) curve analysis a cut-off of 15.5 was calculated to distinguish best between BPH and non-BPH giving an accuracy of 90.2%. Acute urinary retention (AUR) was the predominant sign, which occurred in all BPH patients but only in 6.9% in non-BPH patients. Bladder outlet obstruction (BOO) was also common with a reduced uroflow with 9.5 ± 2.2 ml/sec in non-BPH and 3.0 ± 1.8 ml/sec in BPH (8/11 BPH-patients developed AUR prior to measurement). By digital rectal examinations, benign prostate enlargement was estimated as minimal in 10 of 11 cases of BPH. In urethrocystoscopy kissing lobes were detected in all cases of BPH. Since medical treatment with a-receptor antagonists was not successful, a surgical procedure using a transurethral resection was performed without any complications in all cases. Symptoms did not recur after resection, and BOO improved with increased uroflow measurements with 12.3 ± 4.8 ml/sec 8 days after resection. We conclude that LUTS and BOO are common in freshly transplanted renal allograft recipients. The sudden onset of outlet obstruction without the potentiality of adaptation of urinary bladder may effect lower urinary tract symptoms and bladder outlet obstruction. We conclude that an elevated IPSS over 15.5 in combination with AUR and typical urethrocystoscopy results are the best methods to diagnose BPH. Conversely, our results indicate that uroflowmetry and digital rectal examination are neither sensitive nor specific. In addition, once BPH has been diagnosed and treatment with receptor antagonists does not relieve urinary tract symptoms, surgical resection should be considered.Correspondence to:
Dr. M.J. Koziolek
Abteilung für Nephrologie und Rheumatologie
Georg-August-Universität Göttingen
Robert-Koch-Straße 4
D-37075 Göttingen, Germany
Email: mkoziolek@gmx.de
Originals
Risk factors for peptic ulcer disease in renal transplant
patients -11 years of experience from a single center
Abstract
K.-J. Chen, C.-H. Chen, C.-H. Cheng, M.-Ju Wu and K.-H. Shu
Department of Internal Medicine, Division of Nephrology, Taichung Veterans General Hospital, Institute of Medicine of Chung-Shan Medical University, Taichung, Taiwan
Background: Peptic ulcer disease is a common complication among renal transplant recipients and causes significant morbidity and mortality. Methods: From 1990 through 2000, 465 renal transplant patients were followed-up in our institute. Most patients received corticosteroids and cyclosporine-based immunosuppressive regimen. About one third (n = 156) of them received mycophenolate mofetil. Patients with endoscopy-proved peptic ulcer disease were identified by reviewing medical records. Possible risk factors were analyzed by univariate analysis and multiple logistic regression analysis. Results: Among 465 kidney transplant patients, there were 181 (38.9%) who suffered at least 1 episode of peptic ulcer disease. The most frequent types of peptic ulcer disease were gastritis, gastric ulcer, duodenal ulcer, esophagitis, duodenitis and esophageal ulcer. By multivariate analysis, the use of methylprednisolone pulse therapy (odds ratio = 3.954, 95% confidence interval = 3.154 – 18.312, p = 0.03) and history of pre-transplant peptic ulcer disease (odds ratio = 7.599, 95% CI = 1.211 – 12.905, p < 0.0001) were independent risk factors for posttransplant peptic ulcer disease. Conclusions: Our findings demonstrated that renal transplant patients who undergo methylprednisolone pulse therapy for acute rejection or who have a history of pre-transplant peptic ulcer disease carry a high risk for the development of peptic ulcer disease and deserve intensive antiulcer treatment.Correspondence to:
Dr. K.-H. Shu
Division of Nephrology, Department of Internal Medicine,
Taichung Veterans General Hospital, No. 160, Section 3,
Taichung-Kang Road, Taichung, 407, Taiwan
Email: q60668@yam.com or: khshu@vghtc.vghtc.gov.tw
Originals
Dialysis membrane-dependent removal of middle molecules during hemodiafiltration: the b2-microglobulin/
albumin relationship
Abstract
P.G. Ahrenholz, R.E. Winkler, A. Michelsen, D.A. Lang
1BioArtProducts GmbH, 2Dialyse-Gemeinschaft Nord e.V., Rostock, and 3Fresenius Medical Care Deutschland GmbH, Bad Homburg, Germany
Aim: Current hemodialysis therapy modalities such as online hemodiafiltration (HDF) attempt to enhance solute removal over a wide molecular weight range through a combination of diffusion and convection. While the effects of variations of treatment modalities and conditions have been studied reasonably well, few studies have examined the efficacy of HDF to remove middle molecules in relation to the dialyzer and membrane characteristics. In this investigation, diverse high-flux dialyzers, covering a wide range of membrane permeabilities, were compared under identical in vivo conditions to assess their ability to eliminate larger uremic retention solutes (using b2-microglobulin as a surrogate of middle molecules) without simultaneously causing excessive leakage of useful proteins such as albumin. Patients and methods: In a prospective, crossover study, 3 ESRD patients were treated with 8 different brands of high-flux dialyzers at 4 different ultrafiltration (UF)/ substitution flow rates (QS: 0, 30, 60, 90 ml/ min) in post-dilution HDF mode. Thus, each patient underwent 32 treatment sessions, with a total of 96 treatment sessions conducted during the entire clinical study. Albumin and b2-microglobulin levels were measured in both, dialysate and blood. Both, albumin and b2-microglobulin elimination was dependent upon the permeability of the dialysis membrane as well as on the ultrafiltration/substitution flow rates applied. Results: At the maximum UF rate of 90 ml/min, the total albumin loss (measured in the dialysate) ranged from 300 mg/4 h (for the FLX-15 GWS dialyzers) to 7,000 mg/4 h (for the BS-1.3U dialyzers). Up to 50% reduction of albumin occurred within the first 30 minutes of the dialysis treatment, and the leakage of albumin increased exponentially with increasing UF rates as well as increasing transmembrane pressure (TMP). The various dialyzers could be classified according to their UFR-dependent b2-m reduction rates (RR), into low (< 50%; FLX-15 GWS, CT 150G), medium (50 – 70%; Polyflux 14 S, BLS 814SD, H4) and high (> 70%; BS-1.3U, APS 650, FX 60) removers of middle molecules. One dialyzer type (CT 150G) showed extremely low b2-m RR and relatively high albumin losses. Most membranes, however, showed either low albumin leakage coupled with low b2-m removal, or high b2-m RR but at the expense of considerable albumin leakage. Only 2 membrane types approached the desired balance between high to medium b2-m RR while simultaneously restricting the albumin leakage especially at higher filtration/substitution rates. Conclusion: Our investigations demonstrate that not all dialysis membranes classified as “high-flux” are comparable in their ability to specifically and efficiently remove middle molecules, or curtail the unwanted excessive leakage of essential proteins from the patient’s blood. Thus, the selection of appropriate high-flux dialyzers for specific patient requirements should be based more upon clinical evaluations and analyses rather than on product specifications alone.Correspondence to:
S.K. Bowry
Fresenius Medical Care
Else-Kröner-Straße 1
D-61352 Bad Homburg, Germany
Email: sudhir.bowry@fmc-ag.com
Originals
Hemodialysis for patients bleeding or at risk for bleeding, can be simple, safe and efficient
Abstract
D.N. Stamatiadis, H. Helioti, M. Mansour, M. Pappas, J.G. Bokos and C.P. Stathakis
Division of Nephrology, Laikon General Hospital, Athens, Greece
Aim: Hemodialysis for patients bleeding or at risk for bleeding requires special modalities of treatment that are difficult to perform without potential side effects. A simple, safe and adequate method may be applied. Methods: A modified way of extracorporeal circuit preparation, which focuses on minimizing the blood-air interface and negligible saline flushing of 50 ml/h, is applied for a maximum of 3-hour session with routine (not one-to-one) nursing attendance. Data from 16,954 sessions performed with patients bleeding or at risk for bleeding (15,730 retrospectively and 1,224 prospectively collected) were analyzed. Results: Cumulative failure of treatment, as defined by clotting of the extracorporeal circuit requiring termination of the procedure or replacement of the clotted part, was not more than 5% as expected for anticoagulation-free hemodialysis. For the prospectively recorded sessions, blood flow was 234 ± 30 ml/min with less than 250 ml/min in 42.4% of the sessions. Native blood access was used in 426 (34.8%), double-lumen catheter in 798 (65.2%), 42 were isolated ultrafiltration sessions and 64 blood, 21 plasma, 9 platelet units were transfused. Post/pre urea ratio was 0.50 ± 0.12. Logistic regression showed that among the following: duration of the session, type of dialysis, ultrafiltration rate, hematocrit, number of platelets, serum total protein, transfusions, blood flow and type of access, only blood flow significantly affected failure incidence (coefficient B = –0.041, exp(B) = 0.96, p = 0.04). No complications due to treatment were noted. Conclusion: In patients with active, or at risk for, bleeding, hemodialysis without systemic anticoagulation can be adequately and safely performed almost as a routine session.Correspondence to:
Dr. D. Stamatiadis
18 Volvis Str.
Athens 11142, Greece
Email: dinstam@otenet.gr
Originals
Managing metabolic complications of peritoneal dialysis
Abstract
P. Pennell, C. Rojas, A. Asif and E. Rossini
1Division of Nephrology and Hypertension, University of Miami School of Medicine, and 2Gambro Healthcare, Miami, FL, USA
Aims: The purposes of this paper are: to report our experience employing a comprehensive, multifaceted treatment program to improve the metabolic disturbances of dyslipidemia, hyperglycemia and weight gain observed in our peritoneal dialysis patients, and by post-hoc analysis to demonstrate how the routine clinical lipid profile can be manipulated arithmetically to estimate levels of atherogenic low-density lipids and thereby achieve a more sophisticated clinical analysis of dyslipidemia and its response to therapy. Methods: Data are reported for 56 patients who were stable on peritoneal dialysis for at least 6 months and who had metabolic data available prior to beginning peritoneal dialysis. Metabolic complications of peritoneal dialysis were treated by a comprehensive strategy involving diet, glycemic control and lipid-lowering medications with an emphasis on weight control and exercise. From the measured lipid profile (total cholesterol (TC), high-density lipoprotein (HDL) and triglyceride (TG)), levels of atherogenic low-density lipids (low-density lipoprotein (LDL), non-HDL, very-low-density lipoprotein (VLDL) and intermediate-low-density lipoprotein (IDL) were calculated. Results: Before initiation of peritoneal dialysis therapy, the most common lipid abnormalities were low levels of HDL (59%) and elevated levels of triglyceride (41%) with infrequent elevations of total cholesterol (9%) and low-density lipoprotein (23%). After initiation of peritoneal dialysis therapy, all lipid levels, except HDL, increased significantly, and hyperlipidemia, hyperglycemia and obesity, singly or in combination, occurred in 84% of patients. With treatment, elevated lipid levels decreased significantly with reversal of the adverse cardiovascular risk profile of lipids that developed during peritoneal dialysis therapy, and HDL levels increased significantly. On peritoneal dialysis therapy, all diabetic patients required insulin, and glycemic control was achieved in most patients (79%). Excessive weight gain (10 – 24% body weight) occurred in 20% of peritoneal dialysis patients. Diabetic patients had a higher incidence of being overweight and obese. Post-hoc analysis revealed that levels of VLDL and IDL frequently were elevated both before (57 – 61%) and during (68 – 84%) peritoneal dialysis and that target levels of these atherogenic low-density lipoproteins infrequently (22 – 26%) were achieved. Conclusions: The metabolic complications of peritoneal dialysis are responsive to a comprehensive treatment strategy. Controlling weight gain on peritoneal dialysis therapy may be a difficult challenge for some patients, particularly those who are diabetic. Patients with renal failure and on dialysis, especially peritoneal dialysis, frequently have elevated levels of the atherogenic lipoproteins fragments VLDL and IDL. Future clinical trials should focus on the efficacy and safety of aggressive therapy to achieve target levels of these atherogenic lipids.Correspondence to:
Dr. P. Pennell
Medicine, Psychiatry and Behavioral Science
Division of Nephrology and Hypertension
University of Miami School of Medicine,
P.O. Box 016960 (R-126)
Miami, FL 33101, USA
Email: ppennell@med.miami.edu
Originals
Increasing the placement of native veins arteriovenous fistulae - the role of access surgeons? education and profiling
Abstract
M. Sekkarie
Departments of Medicine, Bluefield Regional Medical Center, Bluefield, WV, USA
Background: The utilization of native veins arteriovenous (AV) fistulae in the US remains low despite their superiority over other types of hemodialysis access. Methods: A nephrologist-driven, quality improvement project that concentrated on access surgeons was utilized to increase fistulae placement. Period I of the project (1998 – 2000) entailed surgeons’ education about advantages of fistulae and methods to increase their placement. During period II (2001 – 2002), referral patterns to surgeons were altered according to their performance, and surgeons out of the area were utilized. Data on patient characteristics, type of access placed and access complications were measured. Results: Fistulae constituted 45% of AV access placed in period I and 79% of those placed in period II. Fistulae prevalence, which was 15% at the end of the pre-project period, increased to 27% at the end of period I and 49% at the end of period II. All changes were statistically significant. Complication rates did not increase. Fistulae placement by surgeons operating in both periods increased in period II. The distribution of types of access placed and outcomes differed significantly among surgeons. Conclusions: Fistulae placement could be increased when the nephrologist works with access surgeons and monitors their performance. Profiling of access surgeons by policy-makers could be a useful method for the identification of surgeons with better skill.Correspondence to:
Dr. M. Sekkarie
510 Cherry St. Suite 306
Bluefield, WV 24701, USA
Email: msekkarie@brmcwv.org
Case reports
Tacrolimus- (FK 506) based immuno-suppression in severe systemic lupus erythematosus
Abstract
D. Politt, B. Heintz, J. Floege and P.R. Mertens
Division of Nephrology and Clinical Immunology, University Hospital of Aachen, Germany
In a 30-year-old male patient systemic lupus erythematosus was diagnosed based on the presence of 8 out of 11 ARA criteria. Disease onset was acute and included renal function impairment with biopsy-proven lupus nephritis (WHO class IV) requiring renal replacement therapy. Although conventional immunosuppressive therapy regimens proved effective in controlling disease activity, all of the administered drugs were accompanied by serious side effects: bilateral femur head necrosis with corticosteroids, allergic skin reaction in response to azathioprine, nephrotoxicity with cyclosporine, nausea and abdominal pain with mycophenolate mofetil and life-threatening septicemia with cyclophosphamide treatment. In search for alternative treatment options, tacrolimus (FK506, trough serum levels 3 – 6 ng/ml) was started. FK506 was well-tolerated and lupus activity completely resolved within 7 months after initiation of therapy. During 36 months of follow-up no arthritic complaints occurred and renal function stabilized at a serum creatinine of 2.1 mg/dl with negative anti-ds-DNA antibodies and ANA titers. In conclusion, FK506 may be considered as alternative immunosuppressive for maintenance treatment in patients with severe lupus erythematosus and side effects to conventional regimens.Correspondence to:
Dr. P.R. Mertens
Medizinische Klinik II, RWTH Aachen
Pauwelsstraße 30
D-52057 Aachen, Germany
Email: Pmertens@ukaachen.de
Case reports
Life-threatening Dobrava hantavirus infection with unusually extended pulmonary involvement
Abstract
M. Schütt1, H. Meisel2, D.H. Krüger2, R. Ulrich2, K. Dalhoff3 and C. Dodt1
1,3Departments of Internal Medicine I and III, University of Lübeck, Lübeck, and 2Institute of Virology, Charité Medical School, Berlin, Germany
In Europe, hantavirus infections usually present as hemorrhagic fever with renal syndrome and its mild form nephropathia epidemica, while clinical cases with severe pulmonary affections are extremely rare and appear to be confined to infections by New World hanta viruses in the Americas. We report on a female patient from Northern Germany, who suffered primarily from severe acute respiratory distress syndrome-like pulmonary failure due to Dobrava hantavirus infection that was complicated by acute renal insufficiency.Correspondence to:
Dr. M. Schütt
University of Lübeck, Department of Internal Medicine I
Ratzeburger Allee 160
D-23538 Lübeck, Germany
Email: morten.schuett@web.de
Case reports
Always look beyond the stones: hyperoxaluria
overlooked
Abstract
T.T. Chung, S. Summers, M. Sheaff and J. Cunningham
1Department of Renal Medicine and Transplantation, and
2Department of Histopathology, The Royal London Hospital, London, UK
We report a case which demonstrates the disastrous consequences of late diagnosis of hyperoxaluria in a 24-year-old woman with nephrocalcinosis, a staghorn calculus and recurrent urinary tract infections. Her initial management at another hospital included multiple percutaneous nephrostomies and lithropsies. Metabolic screening was not undertaken. Hyperoxaluria was finally diagnosed by elevated urine oxalate (1.235 mmol/ 24 h) and renal biopsy, by which time there was already significant reduction of renal function. A diagnosis of hyperoxaluria type I was confirmed by liver biopsy. Despite starting pyridoxine and crystallization inhibitors, her renal function deteriorated, requiring hemodialysis and she was referred for combined liver-renal transplantation. Clinical clues of primary hyperoxaluria type I are a positive family history or presentation with severe renal stones at an unusually early age. Irrespective of the above, all patients with first presentation of renal calculi should undergo metabolic screening, including urine oxalate.Correspondence to:
Dr. T.T. Chung
26 Pelham Road,
Wimbledon, London SW19 1SX, UK
Email: Tengx2@hotmail.com
Case reports
Nutcracker syndrome associated with severe anemia and mild proteinuria
Abstract
T. Oteki, S. Nagase, A. Hirayama, H. Sugimoto, K. Hirayama, K. Hattori and A. Koyama
1Department of Internal Medicine, and 2Department of Urology,
Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan
A 70-year-old man was referred to our hospital with the chief complaint of gross hematuria. Urinalysis revealed gross hematuria (3+, RBC 100/HPF or more) and mild proteinuria (3+, 1.8 g/day) with no urinary casts. Computed tomography of the abdomen showed compression of the left renal vein between the superior mesenteric artery and the aorta. Ultrasonography showed an increased flow velocity at the stenotic portion of the left renal vein. An aortography and selective left renal arteriography showed that there was no evidence of tumor vessels or arterial abnormalities in the arterial phase. However, the venous phase revealed a stenosis of the left renal vein just lateral to the aorta as well as a reflux of contrast material toward the left gonadal vein which was dilated. In addition, cystoscopy revealed left ureteral bleeding. Based on these findings, we made the diagnosis of gross hematuria caused by nutcracker syndrome (NCS). We concluded that the main cause of the anemia and proteinuria in our patient was leakage of blood and this is confirmed by the relationship of red blood cells to protein in the urine because we proved whole blood and plasma protein loss in the urine by calculation. Fourteen months after discharge, both the gross hematuria and proteinuria spontaneously disappeared. This case strongly suggested that the first therapy for hematuria and proteinuria with NCS should be observation.Correspondence to:
Dr. S. Nagase
Department of Internal Medicine
Institute of Clinical Medicine, University of Tsukuba
1-1-1 Ten-nodai, Tsukuba, Ibaraki, 305-8575, Japan
Email: sohji-n@md.tsukuba.ac.jp
Case reports
Trichosporon asahii infection of a dialysis PTFE arteriovenous graft
Abstract
S. Krzossok, R. Birck, S. Henke, H. Hof, F.J. van der Woude and C. Braun
1Vth Department of Medicine (Nephrology/Endocrinology/Rheumatology), and 2Institute of Microbiology, University Hospital Mannheim, University of Heidelberg, Mannheim, Germany
Trichosporon species are the causative agents of superficial skin infections, such as white piedra. Immunocompromised hosts, particularly those with underlying hematological malignancy, are at risk of developing invasive infection, which usually progresses to disseminated life-threatening disease. Peritonitis caused by Trichosporon has been described in end-stage renal disease patients treated with continuous ambulatory peritoneal dialysis. Here, we report on a Trichosporon infection of an arteriovenous graft in a patient on chronic hemodialysis. The infection was successfully treated with fluconazole and total surgical resection of the graft.Correspondence to:
Dr. C. Braun
Fifth Medical Department, Nephrology/Endocrinology/Rheumatology
University Hospital Mannheim, University of Heidelberg
Theodor-Kutzer-Ufer 1-3
D-68167 Mannheim, Germany
Email: BraunC@verw.ma.uni-heidelberg.de
Letters to the Editor
Challenges in establishing a clinically and scientifically robust epoetin policy
Letters to the Editor
No evidence for a role of SLC7A10 in 19q13 in the
etiology of cystinuria
Abstract
C. Schmidt, U. Vester, K. Zerres and T. Eggermann
Letters to the Editor
Treatment of idiopathic retroperitoneal fibrosis with combined administration of corticosteroids and tamoxifen
Abstract
K. Tziomalos, N. Krikis, A. Karagiannis, V. Perifanis,D. Rizopoulou, V. Georgopoulou and F. Harsoulis
