Volume 70, No. 3/2008(September)
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 Clinical Nephrology
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Original
Secular trends in kidney disease: is the decreased incidence of renal replacement therapy due to a decrease in chronic kidney disease incidence?
Abstract
M.L. Thorp1, J.R. Weinstein2, E.S. Johnson3, X. Yang3 and D.H. Smith3
1Department of Nephrology, Kaiser Permanente Northwest, Lake Road Nephrology Center, Milwaukie, 2Department of Medicine, Oregon Health and Science University, Portland, and 3Center for Health Research, Kaiser Permanente Northwest, Portland, OR, USA
Aims: Little is known about trends in renal replacement therapy among patients with chronic kidney disease (CKD) or about changes in the incidence of CKD. We studied the incidence of renal replacement therapy within the population of a health maintenance organization (HMO) both among the entire HMO population and among those with CKD. Methods: We calculated yearly incidence rates of renal replacement therapy for each year from 1998 to 2005. We defined CKD using the National Kidney Foundation definition of 2 estimated glomerular filtration rates below 60 ml/min/1.73 m2 90 or more days apart. Poisson regression assessed year-to-year differences. Results: The number of patients with CKD rose consistently from 3,861 in 1998 to 5,242 in 2005. The proportion of patients who had been diagnosed with hypertension rose from 86.7% (starting renal replacement therapy) or 34.5% (with CKD) to 99.1 and 46.9%. The proportion of patients with diabetes changed little throughout the years studied. The mean estimated glomerular filtration rate among CKD patients rose minimally from 38.4 ml/min/1.73 m2 in 1998 to 39.9 ml/min/1.73 m2 in 2005. Age- and sex-adjusted rates of RRT among patients with CKD varied (p = 0.0034), but did not follow a consistent pattern over time. Conclusions: Incidence of renal replacement therapy among patients with CKD changed little between 1998 and 2005, despite an increase in the number of patients diagnosed with CKD. The discrepancy may be due to increased laboratory identification of CKD.Correspondence to:
D.H. Smith, RPh, PhD; Center for Health Research, Kaiser Permanente Nortwest, 3800 North Interstate Avenue, Portland, OR 97227, USA
Email: David.H.Smith@kpchr.org
Original
The effect of weight loss after bariatric surgery on albuminuria
Abstract
V. Agrawal1, I. Khan1, B. Rai1, K.R. Krause2, D.L. Chengelis2, K.C. Zalesin3, L.L. Rocher4 and P.A. McCullough3
1Department of Internal Medicine, 2Department of Surgery, 3Divisions of Cardiology, Nutrition and Preventive Medicine, and 4Division of Nephrology, William Beaumont Hospital, Royal Oak, MI, USA
Background: Bariatric surgery achieves long-term weight loss in obese adults with improvement of diabetes and hypertension. Little is known about the effect of this weight loss on renal parameters. Methods: We performed a retrospective study of 94 obese adults who had Roux-en-Y gastric bypass surgery with a mean 12-month follow-up. Baseline (preoperative) mean age was 49 years, 76% were female, 37 had blood pressure (BP) ³ 140/90 mmHg and 32 had Type 2 diabetes. 73 patients had normoalbuminuria (urine albumin creatinine ratio (ACR) < 30 mg/g) while 21 had microalbuminuria (ACR 30 – 300 mg/g). Results: At follow-up (postoperative), we observed a decrease in mean body weight (133.6 to 97.9 kg, p < 0.0001), mean hemoglobin A1c (6.3 to 5.6%, p < 0.0001) and mean systolic blood pressure (132.7 to 114.0 mmHg, p < 0.0001). There was a significant reduction in ACR (median with interquartile range) from 9.5 (5 – 28) to 5.5 (3 – 10) mg/g, p < 0.0001. Fewer patients had microalbuminuria (22.2 to 6.2%, p = 0.004) after surgery. Subgroup analysis revealed that significant decrease in ACR was present in the 32 patients with diabetes (16.5 (5 – 67) to 6.0 (4 – 11) mg/g, p = 0.001) and in the 37 patients with metabolic syndrome (8.0 (5 – 16) to 6.0 (3 – 13) mg/g, p = 0.012), while 25 patients with obesity alone had a lower ACR (6.5 (4 – 13) to 4.5 (3 – 8) mg/g, p = 0.270). Multiple linear regression analysis showed change in hemoglobin A1c (p = 0.011) and baseline level of ACR (p < 0.0001) to be significantly associated with change in ACR. Conclusion: We conclude that obese adults have a reduction in albuminuria after surgical weight loss, most importantly in patients with diabetes or metabolic syndrome.Correspondence to:
V. Agrawal, MD; Department of Internal Medicine, William Beaumont Hospital, 3601 West 13 Mile Road, Royal Oak, MI 48073, USA
Email: varunagrawal1996@yahoo.com
Original
Efficiency of laparoscopic-assisted renal biopsy
Abstract
C.M. Anas1, R. Hattori1, Y. Morita2, Y. Matsukawa1, T. Komatsu1, Y. Yoshino1, S. Maruyama2, Y. Yuzawa2, S. Matsuo2 and M. Gotoh1
1Department of Urology, Nagoya University Graduate School of Medicine, and 2Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
Background: This study was made to present our experience and results with transperitoneal laparoscopic-assisted renal biopsy (LARB) in Nagoya University Hospital as a good alternative for open renal biopsy. Methods: 21 patients (14 male, 7 female, mean age 58 years, range 21 – 83 years) were unsuitable for percutaneous renal biopsy. Therefore, they underwent laparoscopic-assisted renal biopsy. The kidney was approached transperitoneally via three ports, cortical tissue was obtained using a 16-gauge gun-mounted semiautomatic biopsy needle. Hemostasis was obtained by applying pressure on the renal puncture using gauze until bleeding had been stopped (range 5 – 20 min). Results: Adequate cortical tissue and accurate diagnoses were obtained in all patients. Mean operative time was 83 min (range 65 – 120 min) and mean estimated blood loss was 5.5 ml (range 1 – 10 ml). There were no intraoperative complications: no open conversion, blood transfusions or gross hematuria. All patients walked about freely and could tolerate regular food on the first postoperative day. The only postoperative complication was a hernia formation at the place of trocar insertion 3 months after the operation in one patient who previously underwent multiple surgery for 3 arterial grafts and appendicitis. Conclusions: LARB is a safe and accurate procedure for obtaining cortical biopsies with minimal blood loss. Although LARB remains a surgical procedure which requires general anesthesia, LARB to date may be considered as a good alternative to open renal biopsy for patients in whom a closed percutaneous approach is either a relative or absolute contraindication.Correspondence to:
Dr. C. Mujeeb Anas, MD, PhD candidate; Department of Urology, Nagoya University, Graduate School of Medicine, Nagoya, Aichi, Japan
Email: japanas2002@hotmail.com
Original
Effects of exercise training during hemodialysis on cardiac baroreflex sensitivity
Abstract
M. Petraki1, E. Kouidi1, D. Grekas2 and A. Deligiannis1
1Laboratory of Sports Medicine, and 2Internal Medicine Clinic Renal Unit, Aristotle University of Thessaloniki, Thessaloniki, Greece
Background: Arterial baroreflex sensitivity (BRS) evaluation has been increasingly used as an index of cardiac autonomic control. Cardiac autonomic dysfunction leading to depressed BRS has been associated with an increased risk of ventricular arrhythmias and sudden death in patients with chronic kidney disease (CKD) on hemodialysis (HD). Aim: The purpose of this study was to investigate the effects of an exercise training program during hemodialysis on BRS in CKD patients. Patients and methods: 43 HD patients participated in the study. They were randomly assigned into either a 7-month exercise training program during HD (Group A: n = 22 patients) or a sedentary control group (Group B: n = 21 patients). Additionally, 20 sex- and age-matched sedentary individuals comprised a healthy control group (Group C). All patients at the beginning and the end of the study underwent a tilt test for evaluation of BRS and an exercise testing with spiroergometric study for cardiorespiratory capacity estimation. The level of Hb, medications and the HD procedure remained stable during the study. Results: At baseline BRS was found to be reduced by 51.5% (p < 0.05) and baroreflex effectiveness index (BEI) by 36.4% (p < 0.05) in Group A compared with Group C. Initially, all HD patients had also significantly lower exercise time and VO2 peak than the healthy subjects. After training, Group A showed a significant improvement in BRS by 23.0% (p < 0.05), in BEI by 27.0% (p < 0.05), in event and ramp count by 35.0% (p < 0.05) and 29.0% (p < 0.05), respectively as well as in VO2 peak by 22.4% (p < 0.05) and in exercise time by 40.9% (p < 0.05). Significant correlations were found between BRS and METs (r = 0.476, p < 0.05), BRS and VO2 peak (r = 0.443, p < 0.05), BEI and METs (r = 0.492, p < 0.05), BEI and VO2 peak (r = 0.467, p < 0.05), event count and VO2 peak (r = 0.715, p < 0.01), event count and exercise time (r = 0.799, p < 0.01), in Group A at the end of the study. Conclusions: Our results indicate that HD patients had considerably reduced cardiorespiratory capacity and impaired cardiac BRS compared to healthy sedentary individuals. Importantly, exercise training during HD yielded a marked increase of the indices representing baroreflex activity in association to the improvement of their functional capacity.Correspondence to:
Prof. Dr. A. Deligiannis MD Professor; Laboratory of Sports Medicine, 26 Ag. Sofias Str, 546 22 Thessaloniki, Greece
Email: stergios@med.auth.gr
Original
Clinical investigation of the effects of pioglitazone on the improvement of insulin resistance and blood pressure in Type 2-diabetic patients undergoing hemodialysis
Abstract
M. Abe1, K. Okada1, F. Kikuchi2 and K. Matsumoto1
1Division of Nephrology, Hypertension and Endocrinology, Department of Medicine, Nihon University School of Medicine, and 2Department of Nephrology and Blood Purification, Yamato Hospital, Tokyo, Japan
Aims: Type 2 diabetes is characterized by a combination of insulin resistance, dyslipidemia, and increased blood pressure. In this study, we evaluated the clinical efficacy of pioglitazone in the treatment of diabetic patients with hypertension undergoing hemodialysis (HD). Methods: An open-label, randomized study was performed using 40 subjects assigned to two groups: one group (pioglitazone group) was administered an add-on pioglitazone therapy (fixed dose, 30 mg) plus conventional oral antidiabetic agents, and the other group (control group) was administered conventional oral agents alone. The treatment efficacy was determined by monitoring the glycemic control and insulin resistance, which were assessed based on the homeostasis model assessment for insulin resistance (HOMA-IR). The safety of and tolerance to the drug were determined by monitoring clinical and laboratory parameters. Results: Pioglitazone was effective in reducing the plasma glucose and hemoglobin A1c levels from the baseline values, beginning at 4 weeks of treatment. It was also effective in reducing the triglyceride levels. The HOMA-IR decreased significantly in the pioglitazone group, and this decrease was maintained until the last measurement, which was at 24 weeks. The systolic and diastolic blood pressure values were statistically lower in the pioglitazone group than in the control group. No serious adverse effects were observed in any of the patients. Conclusions: Pioglitazone is safe and effective for the treatment of Type 2-diabetic patients undergoing HD therapy. A daily dose of 30 mg pioglitazone is sufficient for treating HD patients, regardless of whether or not they are obese. Furthermore, pioglitazone reduced the systolic and diastolic blood pressure in our patients, and this effect requires further investigation.Correspondence to:
M. Abe, MD; Division of Nephrology, Hypertension and Endocrinology, Department of Medicine, Nihon University School of Medicine, 30-1, Oyaguchi-Kamimachi, Itabashi-ku, Tokyo 173-8610, Japan
Email: mabe@med.nihon-u.ac.jp
Orginal
Does the direction of arterial needle in AV fistula cannulation affect dialysis adequacy?
Abstract
S. Ozmen1, A.K. Kadiroglu2, C.A. Ozmen3, R. Danis1, D. Sit1, D. Akin1 and M.E. Yilmaz1
1Department of Nephrology, 2Department of Internal Medicine, and 3Department of Radiology, Dicle University School of Medicine, Diyarbakir, Turkey
Aim: The direction of arterial access needles in fistulas and grafts has been a subject of some controversy and there is no study comparing the results either direction of arterial needle placement in cannulation of arteriovenous fistula. We compared mean urea reduction rate (URR) and Kt/V in the same HD patients when dialyzed via antegrade or retrograde arterial needle cannulation. Materials and methods: This was a study involving 22 adults on maintenance hemodialysis for more than 6 months. Doppler US examinations of arteriovenous fistula were performed in all subjects. Pre-dialysis and post-dialysis blood samples were obtained at the patient’s midweek HD treatment 4 times a month for each direction. Arterial needle was placed in retrograde direction for the first month. On the second month, the direction of arterial needle was converted to antegrade. Means were compared by paired t-test. Results: Mean URR and eKt/Vof retrograde cannulation were 74.2 ± 7.2% and 1.57 ± 0.33. The results were indifferent statistically from those of antegrade cannulation (73.0 ± 8.7% and 1.57 ± 0.35 (p = 0.123)). Mean fistula blood flow was 931 ± 483 ml/min. No cannulation complication was observed during the study period for both directions. Conclusions: Both antegrade and retrograde arterial needle placement may be preferred according to center experience without concern of HD adequacy. Longterm outcomes of antegrade and retrograde arterial needle placement such as AVF failure, thrombosis, and stenosis warrant further studies.Correspondence to:
Dr. S. Ozmen; Dicle University School of Medicine, Department of Nephrology, 21280 Diyarbakir, Turkey
Email: drozmen@gmail.com
Original
Association between dyslipidemia and residual renal function in patients on chronic peritoneal dialysis
Abstract
H.-Y. Chen1,2, T.-W. Kao2, J.-W. Huang2, T.-J. Tsai2 and K.-D. Wu2
1Department of Internal Medicine, Division of Nephrology, Far Eastern Memorial Hospital, and 2Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Tapei, Taiwan
Background: Dyslipidemia and residual renal function (RRF) have a significant impact on the cardiovascular mortality in dialysis patients, but their association in patients on chronic peritoneal dialysis (PD) has not been completely studied. Methods: 170 PD patients were divided into 2 groups based on the RRF (Group I had no RRF and Group II had RRF > 0 ml/min/1.73 m2 BSA). An observational, longitudinal study was performed to elucidate the dyslipidemic state in PD patients with different levels of RRF and the association of dyslipidemia and deterioration of RRF during 3 years. Results: Patients’ basic characteristics and lipid profiles at the initiation of study were similar between the groups. At the end of study, Group I patients had a lower T-CHO (p = 0.001), LDL-C (p = 0.018), HDL-C (p = 0.05) and non-HDL-C (p = 0.003) than Group II. There was a significant correlation between a change in HDL-C and the decline of RRF (r = 0.177, p = 0.048) and it was independent of PD duration and levels of highly sensitive C-reactive protein (r = 0.233, p = 0.04). Conclusion: Our results clearly demonstrate the different longitudinal changes of lipid profiles in PD patients with different RRF and an association between decline of HDL-C and deterioration of RRF.Correspondence to:
K.-D. Wu, MD, PhD; Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, 7 Chung-Sun South Road, Taipei, Taiwan
Email: kdwu@ntuh.gov.tw
Case Report
Renal amyloidosis associated with extracapillary glomerulonephritis and vasculitis in a patient with inflammatory bowel disease treated with infliximab
Abstract
T. Hatakeyama, A. Komatsuda, A. Matsuda, M. Togashi, N. Maki, R. Masai, K. Sawada and H. Wakui
Third Department of Internal Medicine, Akita University School of Medicine, Akita, Japan
A 70-year-old woman with an 11-year history of indeterminate inflammatory bowel disease developed rapidly progressive glomerulonephritis (RPGN) 3 months after the initiation of infliximab therapy. A renal biopsy showed Congo red-positive homogenous deposits in the mesangial area, glomerular capillary walls and arterial walls. Cellular and fibrocellular crescents were observed in 7 of 28 functioning glomeruli. There were findings of active tubulointerstitial nephritis and vasculitis of the small arteries. On electron microscopy, amyloid fibrils were observed in the deposits. Immunohistochemistry showed positive staining for amyloid A (AA) protein. After cessation of infliximab therapy, she was treated with methylprednisolone pulse therapy followed by oral prednisolone therapy. Thereafter, her RPGN was improved. This is a rare case of co-existent focal extracapillary glomerulonephritis with vasculitis and AA renal amyloidosis. Considering the temporal association of drug use with new onset of RPGN in our patient, we suggest a causal link between infliximab and RPGN due to extracapillary glomerulonephritis and vasculitis.Correspondence to:
A. Komatsuda, MD; Third Department of Internal Medicine, Akita University School of Medicine, 1-1-1 Hondo, Akita City, Akita 010-8543, Japan
Email: komatsud@med.akita-u.ac.jp
Case Report
A case of membranous nephropathy associated with Sjögren syndrome, polymyositis and autoimmune hepatitis
Abstract
I. Stefanidis1, M. Giannopoulou1, V. Liakopoulos1, S. Dovas1, F. Karasavvidou2, K. Zachou3, G.K. Koukoulis2 and G.N. Dalekos3
1Department of Nephrology, 2Department of Pathology, and 3Department of Internal Medicine, University of Thessaly, Larissa, Greece
Sjögren syndrome (SS) is a chronic systemic autoimmune disease characterized by lymphocytic infiltration of exocrine glands, especially lacrimal and salivary. The immunologic process which occurs in this syndrome is B cell hyperactivity, which results in production of autoantibodies and immune complexes. SS can exist as a primary disorder or in association with other autoimmune processes. A usually mild, proximal and insidious inflammatory myopathy can occur in patients with SS with a broad clinical and pathological spectrum. Interstitial nephritis with mild proteinuria and tubular dysfunction is the most common renal manifestation of SS, but glomerular involvement due to immune complex deposition may also rarely occur [Goules et al. 2000]. There is an association of SS with hepatic abnormalities, as evidenced by abnormal liver biochemical tests or histological characteristics of primary biliary cirrhosis (PBC), portal tract fibrosis, or autoimmune hepatitis [Abraham et al. 2004]. The pathogenetic mechanism of liver involvement in SS is not clear, but it is possible that hepatic and salivary gland damage share a similar pathology. The combination of Sjögren syndrome with kidney, liver and muscle involvement in one entity is extremely rare and data in the literature are remarkably sparse. We present a case of a 43-year-old female patient suffering from SS accompanied by polymyositis, membranous nephropathy and autoimmune hepatitis.Correspondence to:
I. Stefanidis, MD; Associate Professor of Medicine/Nephrology, Chief of the Department of Nephrology, University Hospital of Larissa, Mezourlo Hill, 41110 Larissa, Greece
Email: stefanid@med.uth.gr
Case Report
Association of idiopathic retroperitoneal fibrosis, rapidly progressive glomerulonephritis and antiproteinase 3 antineutrophil cytoplasmic antibodies (anti PR3-ANCA)
Abstract
P. Martínez-Odriozola1, A. Gutiérrez-Macías1, I. Moina Eguren2 and J. Arrieta Lezama2
1Internal Medicine, and 2Nephrology Departments, Hospital de Basurto, Bilbao, Spain
We report a case of idiopathic retroperitoneal fibrosis and rapidly progressive glomerulonephritis with serum antiproteinase 3 antineutrophil cytoplasmic antibodies (anti-PR3-ANCA), without clinical or histological signs of Wegener’s granulomatosis, in a 46-year-old man. Our case and previously reported cases showing the same association support the hypothesis that the association is not fortuitous, but reflects a common immunological mechanism.Correspondence to:
A. Gutiérrez-Macías, MD; Servicio de Medicina Interna, Hospital de Basurto, Avenida de Montevideo 18, 48013 Bilbao, Spain
Email: alguma@teleline.es
Case Report
An unusual case of xanthogranulomatous pyelonephritis in a leukemia patient
Abstract
Y.K. Wen
Division of Nephrology, Department of Medicine, Changhua Christian Hospital, Changhua, Taiwan
We report a 65-year-old woman with leukemia who presented with urinary tract infection, splenic abscess, and a renal mass. Both urine and pus culture of the splenic abscess yielded Klebsiella pneumoniae. The differential diagnosis of the renal mass by radiological findings included unliquefied renal abscess, xanthogranulomatous pyelonephritis, and renal cell carcinoma. Percutaneous biopsy of the renal mass confirmed the diagnosis of xanthogranulomatous pyelonephritis. Because of high surgical risk, the patient received medical treatment with prolonged antibiotic therapy. With antibiotic therapy only, not only the splenic abscess was cured but also follow-up ultrasonography showed progressive resolution of the renal mass. The occurrence of xanthogranulomatous pyelonephritis has rarely been reported in the absence of urinary tract obstruction or nephrolithiasis. Furthermore, this is the first report of xanthogranulomatous pyelonephritis occurring in patients with leukemia and concurrent with splenic abscess. In addition to describing this unusual case, we provide a short review of xanthogranulomatous pyelonephritis successfully treated with antibiotics only.Correspondence to:
Dr. Y.K. Wen; Division of Nephrology, Department of Medicine, Changhua Christian Hospital, 135 Nanhsiao Street, Changhua, 500, Taiwan
Email: 45440@cch.org.tw
Case Report
Pyelovenous fistula: a rare cause of hematuria
Abstract
O. Demir1, I. Ozdemir1, O. Bozkurt1, M. Seçil2 and A. Esen1
1Department of Urology and 2Department of Radiology, School of Medicine, Dokuz Eylul University, Izmir, Turkey
A 72-year-old female who was admitted to our urology clinic with painless intermittent macroscopic hematuria existing for 3 months with no other voiding symptom was diagnosed with left pyelovenous fistula. Although a rare condition, pyelovenous fistula should be kept in mind when the cause of macroscopic hematuria cannot be diagnosed with routine radiological examinations, and retrograde pyelography should be the method of choice for the diagnosis in this rare condition.Correspondence to:
O. Demir, MD; Dokuz Eylul University, School of Medicine, Department of Urology, 35340 Inciralti/Izmir, Turkey
Email: omer.demir@deu.edu.tr
Case Report
Management of calcific uremic arteriolopathy (calciphylaxis) with a combination of treatments, including hyperbaric oxygen therapy
Abstract
M.D. Arenas1, M.T. Gil1, M.D. Gutiérrez2, T. Malek1, A. Moledous1, A. Salinas2 and F. Alvarez-Ude3
1Servicio de Nefrología, 2Unidad de Medicina Hiperbárica Medibarox, Hospital Perpetuo Socorro, Alicante, and 3Servicio de Nefrología, Hospital General de Segovia, Spain
Calcific uremic arteriolopathy (CUA) is a rare but serious complication of end-stage renal disease presenting as painful cutaneous lesions and progressing to non-healing ulcers and gangrene. This syndrome is associated with calcium and phosphorus deposits within small arteries of the skin. The pathognomonic lesion is vascular calcification with intimal arterial hypertrophy and superimposed small-vessel thrombosis. The condition is being increasingly recognized and reported as a contributing factor to death in dialysis patients, with secondary infection and sepsis as the major cause of mortality. No standard treatment has been established for this syndrome. We present the therapeutic approach employed in two patients, which successfully resulted in healing of the lesions, using a combination of measures to control the factors potentially related to development of CUA and hyperbaric oxygen therapy.Correspondence to:
M.D. Arenas, MD; Hospital Perpetuo Socorro, Plaza Dr Gómez Ulla, 15, 03013, Alicante, Spain
Email: lola@olemiswebs.com
Case Report
Pregnancy in dialysis patients: Two successful cases from a Saudi renal center and resulting management guidelines
Abstract
K. Al Saran and A. Sabry
Prince Salman Center for Kidney Diseases, Riyadh, Kingdom of Arabia
We report two cases of successful pregnancy in two Saudi patients, the first with chronic renal failure on chronic hemodialysis and the second with pre-existing renal disease aggravated by pregnancy.Correspondence to:
Dr. K. Al Saran; Prince Salman Center for Kidney Diseases, Riyadh, Kingdom of Saudi Arabia
Email: khalid_aln@yahoo.co.uk
Letter to the Editor
Comment on Ibernon et al. Clin Nephrol 2008; 69: 395-401
Abstract
P.M. Stassen, J.W. Cohen Tervaert and C.A. Stegeman
