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Hanna RM, Ferrey A, Rhee CM, Sam R, Pearce D, Kalantar-Zadeh K, Don BR. Building a hemodiafiltration system from readily available components for continuous renal replacement therapy under disasters and pandemics: preparing for an acute kidney injury surge during COVID-19. Curr Opin Nephrol Hypertens 2021; 30:93-96. [PMID: 33186219 DOI: 10.1097/mnh.0000000000000658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE OF REVIEW The novel corona virus (SARS-CoV2) has been demonstrated to cause acute kidney injury due to direct cellular toxicity as well as due to a variety of autoimmune glomerular diseases. The concept of a surge of infected patients resulting in an overwhelming number of critical patients has been a central concern in healthcare planning during the COVID-19 era. RECENT FINDINGS One crucial question remains as to how to manage patients with end stage renal disease and acute kidney injury in case of a massive surge of critically ill infected patients. Some publications address practical and ingenious solutions for just such a surge of need for renal replacement therapy. We present a plan for using a blood pump, readily available dialysis filter, and a prefilter and postfilter replacement fluid set up. This is in conjunction with multiple intravenous pumps to develop a simple hemofiltration apparatus. SUMMARY The current set up may be a readily available option for use in critical situations where the need for renal replacement therapy outstrips the capacity of traditional hemodialysis services in a hospital or region.
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Affiliation(s)
- Ramy M Hanna
- Division of Nephrology, Hypertension and Kidney Transplantation, Harold Simmons Center for Kidney Disease Research and Epidemiology
- Division of Nephrology and Hypertension, University of California, Irvine, School of Medicine, Orange, CA, USA
| | - Antoney Ferrey
- Division of Nephrology, Hypertension and Kidney Transplantation, Harold Simmons Center for Kidney Disease Research and Epidemiology
- Division of Nephrology and Hypertension, University of California, Irvine, School of Medicine, Orange, CA, USA
| | - Connie M Rhee
- Division of Nephrology, Hypertension and Kidney Transplantation, Harold Simmons Center for Kidney Disease Research and Epidemiology
- Division of Nephrology and Hypertension, University of California, Irvine, School of Medicine, Orange, CA, USA
| | - Ramin Sam
- Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, CA, USA
| | - David Pearce
- Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, CA, USA
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology, Hypertension and Kidney Transplantation, Harold Simmons Center for Kidney Disease Research and Epidemiology
- Division of Nephrology and Hypertension, University of California, Irvine, School of Medicine, Orange, CA, USA
| | - Burl R Don
- Department of Medicine, Division of Nephrology, University of California Davis, Davis, CA, USA
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Kumar VA, Yeun JY, Depner TA, Don BR. Extended Daily Dialysis vs. Continuous Hemodialysis for ICU Patients with Acute Renal Failure: A Two-Year Single Center Report. Int J Artif Organs 2018; 27:371-9. [PMID: 15202814 DOI: 10.1177/039139880402700505] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Extended daily dialysis (EDD) is an easily implemented alternative to continuous renal replacement therapy (CRRT) in the intensive care unit (ICU). Since EDD offers most of the advantages of CRRT, we sought to compare the effectiveness of these two modalities. In this 2-year study, 54 ICU patients with ARF were treated with either continuous hemodialysis (CHD) or EDD. Oliguria was present in 64% of patients who received CHD vs. 73% of EDD patients (p=NS) while 93% of CHD and 81% of EDD patients required mechanical ventilation (p=NS). Patients treated with EDD were younger than those who received CHD (47.0 ± 12.6 vs. 56.7 ± 13.7, p=0.009), but there were no significant differences in gender or mean APACHE II scores at the time of randomization. Mean arterial blood pressures measured during treatment were maintained between 70 and 80 mmHg for both EDD and CHD and average daily serum electrolyte levels fell within normal ranges for EDD and CHD. Average daily fluid input and output were 5.8 ± 3.3L and 6.0 ± 3.2 L for CHD vs. 3.3 ± 2.6 and 3.0 ± 1.7 L for EDD after exclusion of data from 2 burn patients. Hourly heparin anticoagulation rates were 1080 U/hour for CHD and 643 U/hour for EDD, p=0.02. Anticoagulation-free treatments were performed during 43% of all EDD treatments vs. 21% of all CHD treatments, p<0.001. Clotting of the dialyzer or circuit occurred at least once during 51% of all CHD treatment days vs. 22% of EDD treatments (p<0.001). We conclude that EDD is a safe, effective alternative to CRRT that offers comparable hemodynamic stability and excellent small solute control.
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Affiliation(s)
- V A Kumar
- Department of Medicine, Division of Nephrology, University of California Davis, Sacramento, CA 95817, USA.
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Molfino A, Don BR, Kaysen GA. Comparison of bioimpedance and dual-energy x-ray absorptiometry for measurement of fat mass in hemodialysis patients. Nephron Clin Pract 2013; 122:127-33. [PMID: 23689544 DOI: 10.1159/000350817] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 03/15/2013] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Fat mass (FM) is measured with dual-energy X-ray absorptiometry (DXA), but is expensive and not portable. Multifrequency bioimpedance spectroscopy (BIS) measures total body water (TBW), intracellular water (ICW) and extracellular water (ECW). FM is calculated by subtracting fat-free mass (FFM) from weight assuming a fractional hydration of FFM of 0.73. Hemodialysis (HD) patients, however, have nonphysiologic expansion of ECW. Our aim was to apply a model to estimate FM in HD patients and controls. METHODS We estimated the hydration of FFM in healthy subjects and HD patients with BIS (Impedimed multifrequency) assuming a hydration of 0.73 or using a model allowing ECW and ICW to vary, deriving a value for FM accounting for variances in ECW and ICW. FM was measured by DXA (Hologic Discovery W) in 25 controls and in 11 HD patients. We measured TBW, ECW and ICW with BIS and calculated FM using either weight - TBW/0.73 or with a model accounting for variations in ECW/ICW to estimate FM. RESULTS ECW/ICW was greater in HD patients than in controls (0.83 ± 0.08 vs. 0.76 ± 0.04; p = 0.001). FM (kg) measured by DXA or estimated from TBW using constant hydration or accounting for variations in ECW/ICW was not significantly different in controls or in HD patients. Values obtained by all methods correlated (p < 0.001) and none of the Bland-Altman plots regressed (r(2) = 0.00). FM measured by DXA and by BIS in both controls and HD patients combined correlated (r(2) = 0.871). CONCLUSION Expansion of ECW in HD patients is statistically significant; however, the effect on hydration of FFM was insufficient to cause significant deviation from values derived using a hydration value of 0.73 within the range of expansion of ECW in the HD patient population studied here.
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Affiliation(s)
- Alessio Molfino
- Department of Internal Medicine, University of California, Davis, Calif., USA
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Park-Sigal J, Don BR, Porzig A, Recker R, Griswold V, Sebastian A, Duh QY, Portale AA, Shoback D, Schambelan M. Severe hypercalcemic hyperparathyroidism developing in a patient with hyperaldosteronism and renal resistance to parathyroid hormone. J Bone Miner Res 2013; 28:700-8. [PMID: 23074096 DOI: 10.1002/jbmr.1791] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 09/17/2012] [Accepted: 10/01/2012] [Indexed: 01/16/2023]
Abstract
We evaluated an African American woman referred in 1986 at age 33 years because of renal potassium and calcium wasting and chronic hip pain. She presented normotensive, hypokalemic, hypocalcemic, normophosphatemic, and hypercalciuric. Marked hyperparathyroidism was evident. Urinary cyclic adenosine monophosphate (cAMP) excretion did not increase in response to parathyroid hormone (PTH) infusion, indicating renal resistance to PTH. X-rays and bone biopsy revealed severe osteitis fibrosa cystica, confirming skeletal responsiveness to PTH. Renal potassium wasting, suppressed plasma renin activity, and elevated plasma and urinary aldosterone levels accompanied her hypokalemia, suggesting primary hyperaldosteronism. Hypokalemia resolved with spironolactone and, when combined with dietary sodium restriction, urinary calcium excretion fell and hypocalcemia improved, in accord with the known positive association between sodium intake and calcium excretion. Calcitriol and oral calcium supplements did not suppress the chronic hyperparathyroidism nor did they reduce aldosterone levels. Over time, hyperparathyroid bone disease progressed with pathologic fractures and persistent pain. In 2004, PTH levels increased further in association with worsening chronic kidney disease. Eventually hypercalcemia and hypertension developed. Localizing studies in 2005 suggested a left inferior parathyroid tumor. After having consistently declined, the patient finally agreed to neck exploration in January 2009. Four hyperplastic parathyroid glands were removed, followed immediately by severe hypocalcemia, attributed to "hungry bone syndrome" and hypoparathyroidism, which required prolonged hospitalization, calcium infusions, and oral calcitriol. Although her bone pain resolved, hyperaldosteronism persisted.
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Affiliation(s)
- Jennifer Park-Sigal
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA.
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Eriksson T, Höglund P, Turesson I, Waage A, Don BR, Vu J, Scheffler M, Kaysen GA. Pharmacokinetics of thalidomide in patients with impaired renal function and while on and off dialysis. J Pharm Pharmacol 2010; 55:1701-6. [PMID: 14738599 DOI: 10.1211/0022357022241] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
There is a renewed interest in thalidomide for use in malignancies and systemic inflammatory diseases. Reduced renal function is not uncommon among patients with these disease states but the pharmacokinetics has not been fully investigated. The aim of this study was to investigate the pharmacokinetics of thalidomide in haemodialysis patients while on and off dialysis and in myeloma patients with varying degrees of renal function.
Two studies were performed. To establish the pharmacokinetics of thalidomide in patients with mild to moderate renal failure, blood samples were taken over 12 weeks from 40 patients with multiple myeloma. A second study was performed in six patients with end-stage renal disease both on a non-dialysis day and before and during a haemodialysis session. Thalidomide concentration was determined by HPLC. A one-compartment open model with first-order absorption and elimination was used to fit total thalidomide concentration to population pharmacokinetics and statistical models using the NONMEM program. Clearance and volumes were slightly below 10 L h−1 and 1 L kg−1, respectively, in both patient groups. The inter- and intra-patient variability was low. Clearance was doubled during dialysis. There was no correlation between thalidomide clearance and renal function. In conclusion, the pharmacokinetics of thalidomide in patients with renal failure are very similar to values reported by others for patients with normal renal function. Although clearance during dialysis is doubled, thalidomide dose need not be changed for patients with decreased kidney function. There is also no need for a supplementary dose due to haemodialysis.
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Affiliation(s)
- T Eriksson
- Hospital Pharmacy, University Hospital, 221 85 Lund, Sweden.
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Thornton BD, Hoffman HM, Bhat A, Don BR. Successful treatment of renal amyloidosis due to familial cold autoinflammatory syndrome using an interleukin 1 receptor antagonist. Am J Kidney Dis 2007; 49:477-81. [PMID: 17336710 DOI: 10.1053/j.ajkd.2006.10.026] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Accepted: 10/20/2006] [Indexed: 11/11/2022]
Abstract
Familial cold autoinflammatory syndrome (FCAS) is an autosomal dominant disorder characterized by episodic fever, arthralgias, conjunctivitis, and rash triggered by cold exposure. FCAS is rarely associated with progressive renal insufficiency caused by renal amyloidosis. The genetic defect in patients with this disorder is caused by a mutation in the gene encoding the protein cryopyrin, leading to uninhibited activation of systemic inflammation through specific cellular signaling with increased production of a number of key cytokines, including interleukin 1. We describe the successful treatment of a patient with renal amyloidosis caused by FCAS by using a novel interleukin 1-receptor antagonist. Use of specific anticytokine therapy may be a new paradigm in the treatment of patients with renal amyloidosis caused by systemic inflammatory diseases.
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Affiliation(s)
- Brian D Thornton
- Division of Nephrology, University of California Davis Medical Center, La Jolla, CA, USA
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Don BR, Spin G, Nestorov I, Hutmacher M, Rose A, Kaysen GA. The pharmacokinetics of etanercept in patients with end-stage renal disease on haemodialysis. J Pharm Pharmacol 2006; 57:1407-13. [PMID: 16259772 DOI: 10.1211/jpp.57.11.0005] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Inflammation is strongly associated with malnutrition and cardiovascular risk in patients with chronic renal failure on haemodialysis (HD). The acute-phase inflammatory response, defined by the increased synthesis of positive acute-phase proteins, is stimulated by the production of such cytokines as interleukin 6 (IL-6), interleukin 1 (IL-1) and tumour necrosis factor-alpha TNF-alpha The availability of cytokine antagonists allows testing of the hypothesis that suppression of inflammation reverses the malnutrition-inflammation syndrome in HD patients. Etanercept is a soluble TNF-alpha receptor fusion protein used to suppress inflammation in rheumatoid and psoriatic arthritis. Its metabolism in HD patients is unknown. In a study designed to test the safety and pharmacokinetics of etanercept in HD patients, etanercept was administered to six HD patients with albumin levels above 4.2 g dL(-1) and C-reactive protein levels <5 mg L(-1) (five men, one woman, age range 34-59 years). Etanercept (25 mg) was administered subcutaneously twice weekly immediately after dialysis for 13-16 weeks. Etanercept concentrations were measured pre- and post-dialysis by ELISA. Concentrations were compared graphically to assess whether, firstly, dialysis affects etanercept apparent clearance and, secondly, etanercept kinetics were similar between HD patients and the more extensively studied psoriasis population with normal renal function (PS). The second stage examined model-based parameter predictions of the terminal elimination rate constant (k) for HD patients. Steady-state etanercept levels were comparable between HD and PS patients. Treatment with HD had no effect on etanercept levels. When etanercept was discontinued, the terminal rate constant for HD patients was not significantly different from that observed in PS patients. No adverse effects were noted during the 3-month treatment phase and subsequent 6-month follow-up. Albumin and C-reactive protein levels did not change in these non-inflamed patients during the study period. The pharmacokinetics of etanercept in patients with chronic renal failure on HD are similar to patients with normal renal function. It is, therefore, feasible to administer etanercept to HD patients without adjusting the dose.
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MESH Headings
- Adult
- Anti-Inflammatory Agents, Non-Steroidal/administration & dosage
- Anti-Inflammatory Agents, Non-Steroidal/blood
- Anti-Inflammatory Agents, Non-Steroidal/metabolism
- Etanercept
- Female
- Humans
- Immunoglobulin G/administration & dosage
- Immunoglobulin G/blood
- Immunoglobulin G/metabolism
- Kidney Failure, Chronic/blood
- Kidney Failure, Chronic/metabolism
- Kidney Failure, Chronic/therapy
- Male
- Metabolic Clearance Rate
- Middle Aged
- Models, Biological
- Pharmacokinetics
- Receptors, Tumor Necrosis Factor/administration & dosage
- Receptors, Tumor Necrosis Factor/blood
- Receptors, Tumor Necrosis Factor/metabolism
- Renal Dialysis
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Affiliation(s)
- Burl R Don
- Division of Nephrology, Department of Medicine, University of California Davis Medical Center, Sacramento, CA 95817, USA.
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Tsai JJ, Yeun JY, Kumar VA, Don BR. Comparison and interpretation of urinalysis performed by a nephrologist versus a hospital-based clinical laboratory. Am J Kidney Dis 2005; 46:820-9. [PMID: 16253721 DOI: 10.1053/j.ajkd.2005.07.039] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2005] [Accepted: 07/11/2005] [Indexed: 11/11/2022]
Abstract
BACKGROUND Urinalysis (UA) is considered the most important laboratory test in evaluating patients with kidney disease. Anecdotally, we have observed differences between results of UA performed by nephrologists compared with those performed by certified medical technologists or clinical laboratory scientists that could affect a clinician's diagnosis. Whether there are differences between UA performed by the clinical laboratory and that performed by a nephrologist was determined, and accuracy of diagnosis based on interpretation of the UA was compared. METHODS Urine samples were obtained from 26 patients with acute renal failure (ARF). An aliquot of urine was sent to the clinical laboratory for UA. Nephrologist A, blinded to the patient's clinical information, performed a UA on the other aliquot of urine, generated a report, and assigned the most likely diagnosis for ARF based on UA findings. Nephrologist B, also blinded to the clinical information, reviewed nephrologist A's UA reports and assigned a diagnosis for ARF to each report. Nephrologists A and B both assigned a diagnosis (or diagnoses) for the ARF based on laboratory UA results. These 4 sets of diagnoses were compared with those assigned by the consult nephrologists. RESULTS Nephrologist A correctly diagnosed the cause of ARF in 24 of 26 samples (92.3% success rate) based on his performance of the UA. Diagnoses by nephrologists A and B, based on their review of the clinical laboratory UA report, were correct in only 23.1% and 19.2% of the samples, respectively. Accuracy of diagnosis for nephrologist B improved to 69.3% when she reviewed UA reports from nephrologist A. Nephrologist A's review of urine sediment was significantly more accurate than interpretations by nephrologist A or B of clinical laboratory reports (sign test, P < 0.001). Nephrologist A reported a greater number of renal tubular epithelial (RTE) cells (P < 0.0001), granular casts (P = 0.0017), hyaline casts (P = 0.0233), RTE casts (P = 0.0008), and dysmorphic red blood cells. The laboratory noted a greater number of squamous cells (P = 0.0034). CONCLUSION A nephrologist is more likely to recognize the presence of RTE cells, granular casts, RTE casts, and dysmorphic red blood cells in urine. The laboratory may be reporting RTE cells incorrectly as squamous epithelial cells. Nephrologist-performed UA is superior to laboratory-performed UA in determining the correct diagnosis.
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Affiliation(s)
- Jason J Tsai
- Division of Nephrology, University of California Davis Medical Center, Sacramento, CA 95817, USA
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Abstract
Hypoalbuminemia is the result of the combined effects of inflammation and inadequate protein and caloric intake in patients with chronic disease such as chronic renal failure. Inflammation and malnutrition both reduce albumin concentration by decreasing its rate of synthesis, while inflammation alone is associated with a greater fractional catabolic rate (FCR) and, when extreme, increased transfer of albumin out of the vascular compartment. A vicious cascade of events ensues in which inflammation induces anorexia and reduces the effective use of dietary protein and energy intake and augments catabolism of the key somatic protein, albumin. Hypoalbuminemia is a powerful predictor of mortality in patients with chronic renal failure, and the major cause of death in this population is due to cardiovascular events. Inflammation is associated with vascular disease and likely causes injury to the vascular endothelium, and hypoalbuminemia as two separate expressions of the inflammatory process. Albumin has a myriad of important physiologic effects that are essential for normal health. However, simply administering albumin to critically ill patients with hypoalbuminemia has not been shown to improve survival or reduce morbidity. Thus the inference from these clinical studies suggests that the cause of hypoalbuminemia, rather than low albumin levels specifically, is responsible for morbidity and mortality.
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Affiliation(s)
- Burl R Don
- Division of Nephrology, Department of Medicine, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
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Abstract
Calcific uremic arteriolopathy (calciphylaxis) is one of the more devastating complications that can develop in patients with chronic renal failure. This disorder is associated with calcium-phosphorus deposition in the subcutaneous arterial vessels and presents as a progressive ischemic necrosis of the skin resulting in large subcutaneous ulcerations with eschar formation. Mortality rates are substantially greater in chronic renal failure patients with calciphylaxis, and the major cause of death is infection and sepsis. We have developed a treatment strategy that employs a combination of therapies, which is based on reducing the known risk factors for the development of calciphylaxis as well as utilization of a number of treatment modalities that have been proven successful in the treatment of this disorder.
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Affiliation(s)
- B R Don
- Division of Nephrology, University of California Davis Medical Center, Sacramento, CA 95817, USA.
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Abstract
INTRODUCTION Hypoalbuminemia is a powerful risk factor for cardiovascular mortality in hemodialysis patients (HD). Inflammation causes a decrease in albumin synthesis and an increase in albumin fractional catabolic rate, providing two mechanisms for hypoalbuminemia. The inflammatory response alters the endothelium and plasma protein composition in ways that favor vascular injury. Plasma volume is expanded in HD patients, providing another mechanism for hypoalbuminemia. Fibrinogen levels are an independent risk factor for cardiovascular disease (CVD) in HD patients, and fibrinogen levels are increased in HD patients. Plasma volume expansion is also an independent risk factor for CVD. METHODS Albumin synthesis was measured in 74 HD patients as the disappearance of [125I] human albumin over six weeks. Fibrinogen was measured in plasma. Plasma fibrinogen mass was the product of fibrinogen concentration and plasma volume. RESULTS Albumin synthesis correlated positively with plasma volume (P < 0.001). Fibrinogen concentration and plasma fibrinogen mass both correlated positively with albumin synthesis (P < 0.001). CONCLUSION Albumin levels are reduced as part of the acute-phase response in HD. Plasma volume expansion also tends to decrease albumin concentration, but elicits an increase in its rate of synthesis, which, in turn, is associated with increased fibrinogen levels. Thus, both inflammation and plasma volume expansion factors that reduce albumin concentration and are independent cardiovascular risk factors, independently increase fibrinogen levels.
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Affiliation(s)
- George A Kaysen
- Department of Veterans Affairs Northern California Health Care System, Mather, CA, USA.
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Gandhi S, Kalantar-Zadeh K, Don BR. Thin-glomerular-basement-membrane nephropathy: is it a benign cause of isolated hematuria? South Med J 2002; 95:768-71. [PMID: 12144088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Thin-glomerular-basement-membrane (TGBM) nephropathy is among the most common causes of isolated hematuria. This autosomal dominant disorder is characterized by diffuse thinning of the GBM and is diagnosed by electron microscopic examination of renal biopsy tissue. A study of an affected kindred has revealed a mutation in the alpha chain of type IV collagen, resulting in abnormal basement membrane synthesis. Although the exact prevalence and prognosis is unclear, TGBM is usually regarded as a benign cause of hematuria and not associated with any untoward effect on renal function. We report a case of TGBM nephropathy, with associated proteinuria and progressive renal insufficiency. Other studies similarly contend that TGBM nephropathy may not be so benign. On the basis of these findings, we suggest that in some patients with TGBM nephropathy, progressive renal insufficiency may develop. We recommend a more vigilant approach in patients with TGBM nephropathy, especially if proteinuria is present.
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Affiliation(s)
- Saumil Gandhi
- Division of Nephrology, University of California Davis Medical Center, Sacramento 95817, USA
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Kalantar-Zadeh K, Don BR, Rodriguez RA, Humphreys MH. Serum ferritin is a marker of morbidity and mortality in hemodialysis patients. Am J Kidney Dis 2001. [DOI: 10.1053/ajkd.2001.22433] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Don BR, Rosales LM, Levine NW, Mitch W, Kaysen GA. Leptin is a negative acute phase protein in chronic hemodialysis patients. Kidney Int 2001. [DOI: 10.1046/j.1523-1755.2001.00596.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
BACKGROUND Hypoalbuminemia strongly predicts death in hemodialysis patients and results from both inflammation and malnutrition. One potential link between malnutrition and inflammation is appetite suppression triggered by inflammation. Leptin is secreted by adipose tissue and suppresses appetite, and it is also a positive acute phase protein in the rat. Factored for body weight, leptin is known to be increased in hemodialysis patients, but its relationship to inflammation is unknown. METHODS We examined the relationship between spontaneously occurring activation of the acute phase response and leptin levels in 29 chronic hemodialysis patients. Serum samples were obtained three times weekly for six weeks and then monthly from 29 chronic hemodialysis patients, and the levels of the positive acute phase proteins [C-reactive protein (CRP), alpha1-acid glycoprotein (alpha1 AG), serum amyloid A, ceruloplasmin] and the negative acute phase proteins (albumin and transferrin) as well as leptin and interleukin-6 (IL-6) were measured. RESULTS Positive and negative acute phase proteins were evaluated at the maximum CRP (mean, 9.42 +/- 1.14 mg/dL) and minimum values (mean, 0.41 +/- 0.09 mg/dL). When CRP was elevated, leptin levels were significantly reduced, as were the negative acute phase proteins albumin and transferrin. Serum amyloid A, ceruloplasmin, alpha1 acid glycoprotein, and IL-6 were all significantly increased at the maximum CRP level, compatible with general activation of the acute phase response. The change in leptin correlated negatively with the change in CRP (R = 0.437, P = 0.018), as did changes in albumin (R = 0.620, P < 0.001). CONCLUSIONS Leptin is not increased as a consequence of inflammation in hemodialysis patients, but behaves as a negative rather than as a positive acute phase protein. Inflammation is unlikely to reduce appetite in dialysis patients through a leptin-mediated mechanism.
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Affiliation(s)
- B R Don
- Division of Nephrology, Department of Medicine, University of California Davis Medical Center, Sacramento, 95817, USA.
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Kalantar-Zadeh K, Don BR, Rodriguez RA, Humphreys MH. Serum ferritin is a marker of morbidity and mortality in hemodialysis patients. Am J Kidney Dis 2001; 37:564-72. [PMID: 11228181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
We tested the hypothesis that a high concentration of serum ferritin, a frequently used marker of iron stores in dialysis patients and an acute-phase reactant, may be a marker of morbidity and mortality in these patients. To evaluate the impact of ferritin on morbidity and mortality, we reviewed the 6-month hospitalization rates in our dialysis patients retrospectively and subsequently reviewed the mortality among these patients over a 12-month period of time prospectively. One hundred one adult hemodialysis patients (59 men and 42 women; age, 54 +/- 15 years) who had been on hemodialysis for 38 +/- 27 months were studied. All but 5 patients were on intravenous iron with similar iron administration pattern. In the retrospective cohort, ferritin's correlation coefficients for hospitalization days and frequency (both r = +0.39, P: < 0.001) were higher compared with the albumin correlations for hospitalization days (r = -0.31, P: = 0.001) and frequency (r = -0.28, P: = 0.005) and correlation coefficients remained similarly significant after case-mix adjustment. In the prospective study, the "predeath" value of serum ferritin for 17 deceased patients (891 +/- 476 ng/mL) was higher than both their "initial" value (619 +/- 345 ng/mL, P: = 0.007) and the mean ferritin value of 84 surviving and withdrawing patients (639 +/- 358 ng/mL, P: = 0.001). Although Cox proportional hazard analysis showed a significant odds ratio of death only for serum albumin and not for ferritin, logistic regression analysis using the predeath values confirmed the significant impact of both decreased serum albumin and increased serum ferritin as markers of dialysis mortality. After case-mix adjustment, the relative risks of death for a 500 ng/dL increase in serum ferritin was 2.71 (95% confidence interval, 1.06 to 7.02) and for a 0.5 g/dL decrease in serum albumin was 4.48 (95% confidence interval, 1.77 to 11.33). Hence, serum ferritin is a strong predictor of hospitalization in dialysis patients. Although serum albumin is found to be a strong long-term marker of mortality in hemodialysis patients, an increase in serum ferritin appears to be a more reliable short-term marker of death over a 12-month period. Therefore, in the setting of uniform iron administration, a high serum ferritin may be a morbidity risk factor and a recent increase in serum ferritin may carry an increase in the risk of death in these patients.
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Affiliation(s)
- K Kalantar-Zadeh
- University of California San Francisco, Division of Nephrology, San Francisco General Hospital, San Francisco, CA, USA
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Don BR. The effect of trimethoprim on potassium and uric acid metabolism in normal human subjects. Clin Nephrol 2001; 55:45-52. [PMID: 11200867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
BACKGROUND Trimethoprim used in combination with other antibiotics, has been implicated in causing hyperkalemia and hypouricemia in patients with acquired immune deficiency syndrome (AIDS). In experimental animal models, trimethoprim has been demonstrated to block sodium channels and Na+-K+-ATPase in the distal nephron and thus impair potassium excretion. Although the data from the experimental models suggest that trimethoprim reduces urinary potassium excretion, the retrospective clinical studies have confounding factors that prevent a rigorous demonstration that the hyperkalemia and hypouricemia are due solely to the effects of trimethoprim on solute excretion. AIM The purpose of this study was to evaluate the effect of trimethoprim on potassium and uric acid balance in normal human subjects. METHODS Five normal human subjects were admitted to the general clinical research center and placed on a fixed metabolic diet. After a 4-day control period, the subjects were given trimethoprim (15 mg/kg/day) orally for 5-7 days followed by a 4-day recovery period. Free-flow blood samples and 24-hour urine collections were obtained daily. RESULTS Treatment with trimethoprim resulted in a significant increase in plasma potassium concentration (4.5 +/- 0.1 versus 3.7 +/- 0.1 mmol/l, p < 0.005) and significant decrease in serum uric acid concentration (3.8 +/- 0.4 versus 5.6 +/- 0.5 mg/dl, p < 0.001). Treatment with trimethoprim significantly increased the urinary excretion of uric acid, but did not significantly decrease potassium excretion during the 7-day treatment period. There was, however, a significant decrease in potassium excretion observed during the first 48 hours of trimethoprim treatment. In one subject where repeat studies were performed using different dosages, the effect on potassium and uric acid levels appeared to be dose-dependent. CONCLUSIONS Trimethoprim increases plasma potassium concentration probably by reducing urinary potassium excretion. Trimethoprim decreases serum uric acid levels by augmenting urinary uric acid excretion. This uricosuric effect may be due to the ability of trimethoprim to impair urate reabsorption by the urate-anion exchanger in the proximal tubule.
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Affiliation(s)
- B R Don
- Division of Nephrology, University of California Davis Medical Center, Sacramento 95817, USA.
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Don BR, Kaysen GA. Assessment of inflammation and nutrition in patients with end-stage renal disease. J Nephrol 2000; 13:249-59. [PMID: 10946803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Malnutrition commonly occurs in patients with end-stage renal disease (ESRD), and hypoalbuminemia is considered the best clinical marker of malnutrition and mortality in this population. Recently, it has been recognized that a substantial number of patients with ESRD have serologic evidence of an augmented inflammatory response and moreover, inflammation may be as or more important than protein intake in causing hypoalbuminemia. In addition, the presence of inflammation may be a more powerful predictor of mortality than dietary protein intake. The presence of inflammation is often subtle and is detected by increased levels of the positive acute phase proteins, most notably C-reactive protein. The causes of the stimulation of the systemic inflammatory response may include reaction to dialyzer membranes, increased production of advanced glycosylated end-products, oxidative stress of uremia and overt and occult infections, especially unrecognized arteriovenous graft infections. There is a complex relationship between inflammation and nutritional status. Inflammation can cause both anorexia with protein-calorie malnutrition as well as wasting through mechanisms mediated by cytokines. Novel therapies will need to be developed to counter this systemic inflammation since it appears to be a major cause of mortality in patients with end-stage renal disease.
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Affiliation(s)
- B R Don
- Division of Nephrology, University of California Davis Medical Centre, Sacramento, USA.
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Giacchetti G, Sechi LA, Griffin CA, Don BR, Mantero F, Schambelan M. The tissue renin-angiotensin system in rats with fructose-induced hypertension: overexpression of type 1 angiotensin II receptor in adipose tissue. J Hypertens 2000; 18:695-702. [PMID: 10872553 DOI: 10.1097/00004872-200018060-00006] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Fructose feeding induces hypertension, insulin-resistance and hypertriglyceridemia in Sprague-Dawley rats. The mechanisms of fructose-induced hypertension are as yet unknown. Here we investigate the effects of fructose feeding and of varying salt intake on blood pressure, glucose tolerance, plasma renin activity, and tissue angiotensinogen, renin, and AT1 receptor mRNA levels in this model of hypertension. DESIGN AND METHODS To investigate the role of the renin-angiotensin system in fructose-induced hypertension we measured angiotensinogen, renin and angiotensin II type 1 (AT1) receptor mRNA levels in tissues of Sprague-Dawley rats that were fed either standard rat chow or a diet containing 66% fructose. RESULTS Blood pressure (P < 0.05) and triglyceride (P < 0.01) levels were significantly greater in the fructose-fed animals. Plasma glucose and insulin responses to an oral glucose load were significantly greater (P< 0.05) in fructose-fed than control rats. Angiotensinogen mRNA levels in liver and fat, and renin mRNA levels in kidney did not differ between fructose-fed and control animals. Levels of AT1 receptor mRNA were significantly greater in the fat obtained from fructose-fed rats than in that from control rats (P< 0.05), but this was not so in the kidney. To determine whether fructose-induced hypertension is dependent on dietary salt content, rats were fed standard rat chow and a fructose-enriched diet with low and high sodium chloride concentrations. Blood pressure increased significantly (P< 0.05) only in the fructose-fed rats receiving the high-salt diet Similarly, increased AT1 receptor mRNA levels were observed only in the fructose-fed rats that were maintained on the high-salt diet CONCLUSIONS Fructose feeding induces hypertension in normal- or high-salt fed animals and it is associated with an increased expression of the AT1 receptor in adipose tissue. These findings suggest that AT1 receptors might play a role in the pathophysiology of metabolic and hemodynamic abnormalities induced by fructose feeding.
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Affiliation(s)
- G Giacchetti
- Division of Endocrinology, University of Ancona, Ospedale 'Umberto l'Torrette, Italy.
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Perini S, LaBerge JM, Pearl JM, Santiestiban HL, Ives HE, Omachi RS, Graber M, Wilson MW, Marder SR, Don BR, Kerlan RK, Gordon RL. Tesio catheter: radiologically guided placement, mechanical performance, and adequacy of delivered dialysis. Radiology 2000; 215:129-37. [PMID: 10751478 DOI: 10.1148/radiology.215.1.r00mr43129] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE Tunneled catheters are an alternative means of vascular access for patients in need of hemodialysis who cannot undergo dialysis through a surgical shunt. This study was undertaken to evaluate the performance of the Tesio dialysis catheter. MATERIALS AND METHODS A prospective study of the Tesio catheter was performed. Follow-up data regarding catheter function and adequacy of dialysis were obtained from nine hemodialysis facilities. RESULTS Seventy-nine Tesio catheters were placed in 71 patients. Immediate technical success was 99% (78 of 79 catheters). The procedure complication rate was 9% (seven catheters). Only two complications required intervention: one fatal air embolism and one chest wall hematoma. Sixty-seven catheters in 60 patients were followed up for a total of 4,367 catheter days. Overall, catheter-related infection occurred in 9% (six of 67 catheters). Primary catheter patency was 87% at 1 week, 82% at 1 month, 72% at 3 months, and 66% at 6 months. Mean blood flow was 286 mL/min immediately after insertion, 301 mL/min at 3 months, and 306 mL/min at 6 months. Adequate dialysis dose as reflected by a urea reduction ratio of 60 or more or a urea kinetic modeling, or Kt/V, value of 1.2 or more was observed on at least one occasion for 74% and 76% of catheters, respectively. CONCLUSION The Tesio catheter is a reasonable means of vascular access for patients who undergo dialysis but are not candidates for surgical shunt placement.
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Affiliation(s)
- S Perini
- Departments of Radiology, University of California San Francisco, Box 0628, 505 Parnassus Ave, San Francisco, CA 94143-0628, USA. perini@ itsa.ucsf.edu
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Kalinyak JE, Sechi LA, Griffin CA, Don BR, Tavangar K, Kraemer FB, Hoffman AR, Schambelan M. The renin-angiotensin system in streptozotocin-induced diabetes mellitus in the rat. J Am Soc Nephrol 1993; 4:1337-45. [PMID: 8130360 DOI: 10.1681/asn.v461337] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
It has been hypothesized that the renin-angiotensin system plays a pathophysiologic role in the renal hemodynamic abnormalities that occur in diabetes mellitus and thereby contributes to the development of diabetic nephropathy. In this study, the tissue-specific regulation of renin and angiotensinogen mRNA levels and the abundance of glomerular angiotensin II receptors were examined in male Sprague-Dawley rats (160 to 240 g) made diabetic with streptozotocin. One subgroup of diabetic rats remained untreated, whereas a second diabetic subgroup received twice-daily doses of insulin to ameliorate hyperglycemia. Animals were euthanized 2 wk after the induction of diabetes. Mean plasma glucose levels at the time of euthanasia were significantly elevated in the untreated diabetic animals when compared with controls or insulin-treated diabetic rats. Weight gain was similar in control and insulin-treated diabetic rats, whereas the untreated diabetic rats gained significantly less. Plasma renin concentration did not differ between control, diabetic, and insulin-treated diabetic groups. In the kidney, no significant differences were found in either angiotensinogen or renin mRNA levels in diabetic animals, whereas glomerular angiotensin II receptors were significantly less abundant in untreated rats as compared with control or insulin-treated diabetic subgroups. Angiotensinogen mRNA levels were significantly lower in the livers and adrenals of diabetic rats in comparison to those in controls and insulin-treated diabetic rats, whereas angiotensinogen mRNA levels in the brain remained unaltered.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J E Kalinyak
- Department of Medicine, University of California, San Francisco General Hospital 94110
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al-Uzri A, Holliday MA, Gambertoglio JG, Schambelan M, Kogan BA, Don BR. An accurate practical method for estimating GFR in clinical studies using a constant subcutaneous infusion. Kidney Int 1992; 41:1701-6. [PMID: 1501425 DOI: 10.1038/ki.1992.243] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- A al-Uzri
- Department of Pediatrics, School of Medicine, University of California, San Francisco
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Abstract
It has been speculated that glucoregulatory hormones and/or renal autacoids mediate the increase in glomerular filtration rate (GFR) induced by the administration of protein or amino acids. Because infusion of a mixture of amino acids (AA mix), but not of branched-chain amino acids (BCAA) alone, increases GFR, we performed a crossover study in seven normal subjects in which the glomerular hemodynamic effects of separate 3-h infusions of these two amino acid solutions were compared with changes in potential mediators of this response, i.e., glucoregulatory hormones, renin, vasodilatory prostaglandins (PGs), and guanosine 3',5'-cyclic monophosphate (cGMP). As expected, infusion of the AA mix but not BCAA resulted in a prompt and sustained increase in GFR. Both infusions caused a significant increase in plasma insulin, whereas glucagon increased only with the AA mix. Plasma growth hormone was initially unchanged with both infusions but increased after 2 h of BCAA. Neither infusion significantly increased the urinary excretion of PGE2, 6-keto-PGF1 alpha, or cGMP. Both infusions resulted in a small but significant decrease in plasma renin activity. Infusion of BCAA but not the AA mix resulted in a progressive decrease in plasma glucose and potassium concentrations and an increase in renal sodium reabsorption that may have resulted from stimulation of insulin secretion that was not counterbalanced by a simultaneous increase in glucagon. Thus only changes in glucagon exhibited a significant temporal relationship with changes in GFR, lending further support to a role for glucagon as a mediator of amino acid-induced glomerular hyperfiltration.
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Affiliation(s)
- L Wada
- Medical Service, San Francisco General Hospital Medical Center, California 94110
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Don BR, Kaysen GA, Hutchison FN, Schambelan M. The effect of angiotensin-converting enzyme inhibition and dietary protein restriction in the treatment of proteinuria. Am J Kidney Dis 1991; 17:10-7. [PMID: 1986564 DOI: 10.1016/s0272-6386(12)80243-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Both angiotensin-converting enzyme inhibitors and dietary protein restriction have been reported to reduce urinary protein losses in patients with chronic glomerular diseases. We evaluated these two therapies in 12 such patients ingesting a constant metabolic diet containing 1.6 g protein/kg body weight per day. After a steady-state was achieved during a 3-week baseline period, patients were randomly assigned to either enalapril, titrated to reduce mean arterial pressure by 10 mm Hg, or an isocaloric 0.8 g/kg protein diet. Five patients in each group completed 3 additional weeks of observation during the treatment period. Enalapril resulted in an average reduction in urinary protein and albumin losses of 26% and 33%, respectively, without reducing creatinine clearance. Albumin synthesis was unchanged and nitrogen balance increased slightly (+142.8 +/- 85.7 mmol/d [+2.0 +/- 1.2 g/d], P = 0.075). Dietary protein restriction had no consistent effect on proteinuria or albuminuria, whereas albumin synthesis (25.9 +/- 3.4 v 21.5 +/- 2.9 g/d/1.73 m2, P less than 0.05) and nitrogen balance (-135.6 +/- 92.8 mmol/d [-1.9 +/- 1.3 g/d], P = 0.10) decreased. Both therapies resulted in a modest increase in plasma potassium concentration. Whether the maintenance of albumin synthesis in the presence of a reduction in urinary protein losses will convey a long-term advantage to treatment of proteinuric patients with angiotensin-converting enzyme inhibitors remains to be determined.
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Affiliation(s)
- B R Don
- Medical Service, San Francisco General Hospital Medical Center, CA 94110
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Abstract
Transient hyperkalemia has been reported to occur in patients with acute glomerulonephritis, but the pathogenetic mechanism has not been investigated systematically. We studied the mechanism of hyperkalemia (5.7 to 6.7 mmol/liter) in four men with post-infectious glomerulonephritis. All four patients had clinical findings consistent with acute glomerulonephritis (edema, hypertension, proteinuria, hematuria, and an elevated ASO titer) and a renal biopsy performed in three of the patients confirmed the diagnosis. In comparison to normal subjects (N = 18), plasma aldosterone (5.4 +/- 1.6 vs. 22.8 +/- 2.6 ng/dl, P less than 0.005) and plasma renin activity (0.3 +/- 0.2 vs. 4.3 +/- 0.6 ng/ml/hr, P less than 0.005) were reduced. Hyperkalemia resolved within one to two weeks in two patients as the nephritis resolved and diuresis ensued, and aldosterone and renin levels obtained at follow-up visits were normal. Hyperkalemia persisted despite furosemide-induced diuresis in the other two patients, but resolved with fludrocortisone treatment. Thus, hyperkalemia in patients with acute glomerulonephritis is a manifestation, in part, of hyporeninemic hypoaldosteronism. It is ameliorated by mineralocorticoid therapy and improves spontaneously with resolution of the glomerulonephritis.
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Affiliation(s)
- B R Don
- Medical Service, San Francisco General Hospital Medical Center, California
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Affiliation(s)
- B R Don
- Medical Service, San Francisco General Hospital Medical Center
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Don BR, Wada L, Kaysen GA, Schambelan M. Effect of dietary protein restriction and angiotensin converting enzyme inhibition on protein metabolism in the nephrotic syndrome. Kidney Int Suppl 1989; 27:S163-7. [PMID: 2561515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- B R Don
- Medical Service, San Francisco General Hospital Medical Center, California
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Abstract
The quantity of protein in the diet modulates glomerular function. To study the effect of dietary protein intake on glomerular eicosanoid production, rats were randomized to either a high- (40%) or low- (8.5%) protein isocaloric diet. Ten to fourteen days later glomeruli were isolated and incubated in the absence (basal) and presence (stimulated conditions) of arachidonic acid, and production rates of prostaglandin (PG) E2, PGF2 alpha, and thromboxane B2 (TxB2) were determined by direct radioimmunoassay. Under basal conditions, glomerular production of all three eicosanoids was significantly greater in rats ingesting the high-protein diet. Glomerular production of PGE2 and TxB2 was also greater in animals fed the high-protein diet in the presence of arachidonic acid, suggesting that glomerular cyclooxygenase activity was augmented. In contrast, ingestion of a high-protein diet was not associated with a significant increase in eicosanoid production by renal papillae or in TxB2 release by clotting blood. To investigate the potential role of the renin-angiotensin system in the dietary protein-induced modulation of glomerular eicosanoid production, rats ingesting a high- or low-protein diet were randomized to treatment with an angiotensin-converting enzyme inhibitor or no therapy. Enalapril attenuated the dietary protein-induced augmentation in glomerular eicosanoid production. This effect occurred only when administered in vivo, since the active metabolite enalapril did not alter PGE2 production by isolated glomeruli when added in vitro. Dietary protein intake also modulated glomerular eicosanoid production in three models of experimental renal disease in the rat (streptozotocin-induced diabetes mellitus, Heymann nephritis, and partial renal ablation).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- B R Don
- Medical Service, San Francisco General Hospital Medical Center 94110
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Schambelan M, Don BR, Kaysen GA, Blake S. Abnormalities of glomerular eicosanoid metabolism in states of glomerular hyperfiltration. Adv Exp Med Biol 1989; 259:275-304. [PMID: 2696356 DOI: 10.1007/978-1-4684-5700-1_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- M Schambelan
- Medical Service, San Francisco General Hospital Medical Center, California 94110
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Don BR, Schambelan M. Diabetes, dietary protein and glomerular hyperfiltration. West J Med 1987; 147:449-55. [PMID: 2891223 PMCID: PMC1025906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
These discussions are selected from the weekly staff conferences in the Department of Medicine, University of California, San Francisco. Taken from transcriptions, they are prepared by Drs Homer A. Boushey, Professor of Medicine, and David G. Warnock, Associate Professor of Medicine, under the direction of Dr Lloyd H. Smith, Jr, Professor of Medicine and Associate Dean in the School of Medicine. Requests for reprints should be sent to the Department of Medicine, University of California, San Francisco, School of Medicine, San Francisco, CA 94143.
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