Uremia Workup

  • Author: A Brent Alper Jr, MD, MPH; Chief Editor: Vecihi Batuman, MD, FACP, FASN   more...
 
Updated: Mar 17, 2010
 

Laboratory Studies

  • The diagnosis of renal failure is primarily based on an abnormal GFR or creatinine clearance, usually evident due to an elevated serum creatinine level. GFR determination can be accomplished by 24-hour urine collection for creatinine clearance, although this is often cumbersome and inaccurate due to improper collection. All patients with an abnormal creatinine clearance should have their GFR estimated using one of several formulas that use easily obtained values. These include the Modification of Diet in Renal Disease (MDRD) formula or the Cockcroft-Gault formula. Both formulas have been shown to provide similar values within a wide range of patient ages and to be accurate in those with renal insufficiency, regardless of race or sex.
  • It is very important to determine if the renal failure is acute or chronic, as acute renal failure will likely be reversible if treated properly. Review of the patient's history as well as previous laboratory values can be very helpful in this regard.
  • Other laboratory tests to consider for abnormalities prevalent with clinical uremia include hemoglobin, calcium, phosphate, PTH, albumin, potassium, and serum bicarbonate values.
  • Urinalysis with microscopic examination should be performed on all patients to evaluate for the presence of protein, cellular casts, oval fat bodies, ketones, hemoglobin, myoglobin, and pH.
Next

Imaging Studies

  • A renal ultrasound study is indicated to estimate the size of the kidneys and to evaluate for hydronephrosis or obstruction.
    • Hydronephrosis can occur with ureteral or bladder obstruction, retroperitoneal fibrosis, massive abdominal tumors due to cervical or prostate cancers, and other structural abnormalities.
    • Renal ultrasound is performed to determine the size and shape of the kidneys; large kidneys are associated with diseases, such as early diabetic nephropathy, multiple myeloma, polycystic kidney disease, or HIV associated glomerulonephritis, while small kidneys usually indicate chronic, irreversible damage from diseases, such as hypertensive nephrosclerosis, ischemic nephropathy, or any other long-standing kidney disease.
    • CT scan of the abdomen may be indicated to rule out retroperitoneal fibrosis, pelvic masses, lymphadenopathy, or lymphoma if bilateral hydronephrosis is found on ultrasound images and no obvious etiology is present (eg, stone, bladder mass, ureteral mass).
  • MRI arteriograms can be used to assess the kidneys for renal artery stenosis, acute arterial thrombosis, or aortic dissection involving the aorta and renal arteries. It is important to consider renal artery stenosis in the differential because it is one cause of renal failure that is potentially reversible by angioplasty or bypass surgery of the affected renal artery.
  • Consider a brain CT scan in the event of a significant change in mental status, especially if the change occurs after a fall or in association with mild trauma. Spontaneous subdural hematomas occur in patients with uremia, particularly if the BUN level is greater than 150-200 mg/dL.
Previous
Next

Other Tests

  • Nuclear medicine radioisotope (iothalamate) clearances can also be obtained and are the criterion standard for measuring GFR. However, this test is time-consuming and more expensive than estimating GFR using either the MDRD formula or the Cockcroft-Gault formula.
Previous
Next

Procedures

  • To make an accurate diagnosis of ARF or CRF, a renal biopsy is necessary. However, if the renal failure has been slowly progressive and the kidneys are small, renal biopsy results are of little benefit. In the setting of rapidly progressive renal failure or ARF for which the etiology is not known, a renal biopsy is indicated to determine if potentially reversible or treatable renal disorders are present.
Previous
Next

Histologic Findings

Histologic findings vary depending on the underlying etiology. However, in the setting of late stage CKD and uremia in which renal function has deteriorated over a prolonged period and the kidneys are relatively small, renal biopsy results may show significant glomerulosclerosis and obsolescent glomeruli (completely scarred and sclerosed) with significant interstitial fibrosis. These findings are nonspecific and do not aid in determining the underlying cause of renal failure. In the setting of uremia, performing a renal biopsy in a patient with small kidneys may be dangerous because of comorbid disease and the increased risk of bleeding. Consider this procedure if a reversible cause of renal function is in the differential.

Previous
Next

Staging

Staging is determined by the GFR (creatinine clearance). Currently, the National Kidney Foundation no longer recognizes the terms chronic renal insufficiency (CRI) or CRF, but rather it recognizes the 5 stages of CKD based on the estimated GFR (eGFR), as calculated by the MDRD formula.

  • Stage 1 - Kidney damage with normal GFR, 90 mL/min or greater
  • Stage 2 - Kidney damage with a mild decrease in GFR, 60-89 mL/min
  • Stage 3 - Kidney damage with a moderate decrease in GFR, 30-59 mL/min
  • Stage 4 - Kidney damage with a severe decrease in GFR, 15-29 mL/min
  • Stage 5 - End-stage renal disease, less than 15 mL/min or on dialysis
Previous
Proceed to Treatment & Management
 
 
Contributor Information and Disclosures
Author

A Brent Alper Jr, MD, MPH  Associate Professor of Medicine, Section of Nephrology and Hypertension, Department of Medicine, Tulane University School of Medicine

A Brent Alper Jr, MD, MPH is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, American Society of Hypertension, American Society of Nephrology, National Kidney Foundation, and Phi Beta Kappa

Disclosure: Nothing to disclose.

Coauthor(s)

Rajesh G Shenava, MD  Assistant Professor of Medicine, Section of Nephrology and Hypertension, Department of Internal Medicine, Louisiana State University Health Sciences Centre

Rajesh G Shenava, MD is a member of the following medical societies: American College of Physicians, American Society of Nephrology, National Kidney Foundation, and Renal Physicians Association

Disclosure: Nothing to disclose.

Bessie A Young, MD, MPH  Associate Professor, Division of Nephrology, Department of Medicine, University of Washington; Director of Home Hemodialysis, Northwest Kidney Center, Seattle

Bessie A Young, MD, MPH is a member of the following medical societies: American College of Physicians, American Diabetes Association, American Society of Nephrology, International Society of Nephrology, and National Kidney Foundation

Disclosure: NxStage Grant/research funds Principal Investigator; Amgen Grant/research funds Principal Investigator

Specialty Editor Board

Donald A Feinfeld, MD, FACP, FASN  Consulting Staff, Division of Nephrology & Hypertension, Beth Israel Medical Center

Donald A Feinfeld, MD, FACP, FASN is a member of the following medical societies: American Academy of Clinical Toxicology, American Society of Hypertension, American Society of Nephrology, and National Kidney Foundation

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD  Senior Pharmacy Editor, eMedicine

Disclosure: eMedicine Salary Employment

Eleanor Lederer, MD  Consulting Staff, Louisville VA Hospital; Professor of Medicine; Interim Chief of Nephrology; Director of Nephrology Training Program; Director, Metabolic Stone Clinic; Director of Outpatient Clinics, Kidney Disease Program, University of Louisville School of Medicine

Eleanor Lederer, MD is a member of the following medical societies: American Association for the Advancement of Science, American Federation for Medical Research, American Society for Biochemistry and Molecular Biology, American Society for Bone and Mineral Research, American Society of Nephrology, American Society of Transplantation, International Society of Nephrology, Kentucky Medical Association, National Kidney Foundation, and Phi Beta Kappa

Disclosure: Nothing to disclose.

Rebecca J Schmidt, DO, FACP, FASN  Professor of Medicine, Section Chief, Department of Medicine, Section of Nephrology, West Virginia University School of Medicine

Rebecca J Schmidt, DO, FACP, FASN is a member of the following medical societies: American College of Physicians, American Medical Association, American Society of Nephrology, International Society of Nephrology, National Kidney Foundation, Renal Physicians Association, and West Virginia State Medical Association

Disclosure: Abbott Grant/research funds Speaking and teaching; Genzyme Honoraria Consulting; Amgen Honoraria Speaking and teaching; Ortho Biotech Honoraria Speaking and teaching

Chief Editor

Vecihi Batuman, MD, FACP, FASN  Professor of Medicine, Section of Nephrology-Hypertension, Tulane University School of Medicine; Chief, Medicine Service, Southeast Louisiana Veterans Health Care System

Vecihi Batuman, MD, FACP, FASN is a member of the following medical societies: American College of Physicians, American Society of Hypertension, American Society of Nephrology, and International Society of Nephrology

Disclosure: Nothing to disclose.

References

  1. Piorry PA, l'Heritier D. Traite des Alterations du Sang. Paris, France: Bury & JB Bailliere; 1840.

  2. Carrero JJ, Witasp A, Stenvinkel P, et al. Visfatin is increased in chronic kidney disease patients with poor appetite and correlates negatively with fasting serum amino acids and triglyceride levels. Nephrol Dial Transplant. Mar 2010;25(3):901-6. [Medline].

  3. Almoznino-Sarafian D, Shteinshnaider M, Tzur I, et al. Anemia in diabetic patients at an internal medicine ward: Clinical correlates and prognostic significance. Eur J Intern Med. Apr 2010;21(2):91-96. [Medline].

  4. Teng M, Wolf M, Lowrie E, Ofsthun N, Lazarus JM, Thadhani R. Survival of patients undergoing hemodialysis with paricalcitol or calcitriol therapy. N Engl J Med. Jul 31 2003;349(5):446-56. [Medline].

  5. Sprague SM, Llach F, Amdahl M, Taccetta C, Batlle D. Paricalcitol versus calcitriol in the treatment of secondary hyperparathyroidism. Kidney Int. Apr 2003;63(4):1483-90. [Medline].

  6. Schlieper G, Aretz A, Verberckmoes SC, et al. Ultrastructural Analysis of Vascular Calcifications in Uremia. J Am Soc Nephrol. Mar 4 2010;[Medline].

  7. El-Agroudy AE, El-Baz A. Soluble Fas: a useful marker of inflammation and cardiovascular diseases in uremic patients. Clin Exp Nephrol. Jan 26 2010;[Medline].

  8. Muscaritoli M, Molfino A, Bollea MR, et al. Malnutrition and wasting in renal disease. Curr Opin Clin Nutr Metab Care. Jul 2009;12(4):378-83. [Medline].

  9. Fakhouri F, Roumenina L, Provot F, et al. Pregnancy-Associated Hemolytic Uremic Syndrome Revisited in the Era of Complement Gene Mutations. J Am Soc Nephrol. Mar 4 2010;[Medline].

  10. Chuang YW, Shu KH, Yu TM, et al. Hypokalaemia: an independent risk factor of Enterobacteriaceae peritonitis in CAPD patients. Nephrol Dial Transplant. May 2009;24(5):1603-8. [Medline].

  11. Seyffart G, Schulz T, Stiller S. Use of two calcium concentrations in hemodialysis--report of a 20-year clinical experience. Clin Nephrol. Mar 2009;71(3):296-305. [Medline].

  12. [Best Evidence] Singh AK, Szczech L, Tang KL, Barnhart H, Sapp S, Wolfson M, et al. Correction of anemia with epoetin alfa in chronic kidney disease. N Engl J Med. Nov 16 2006;355(20):2085-98. [Medline].

  13. Drüeke TB, Locatelli F, Clyne N, Eckardt KU, Macdougall IC, Tsakiris D, et al. Normalization of hemoglobin level in patients with chronic kidney disease and anemia. N Engl J Med. Nov 16 2006;355(20):2071-84. [Medline].

  14. Fouque D, Laville M. Low protein diets for chronic kidney disease in non diabetic adults. Cochrane Database Syst Rev. Jul 8 2009;CD001892. [Medline].

  15. Baigent C, Burbury K, Wheeler D. Premature cardiovascular disease in chronic renal failure. Lancet. Jul 8 2000;356(9224):147-52. [Medline].

  16. Bolton WK, Kliger AS. Chronic renal insufficiency: current understandings and their implications. Am J Kidney Dis. Dec 2000;36(6 Suppl 3):S4-12. [Medline].

  17. Fort J. Chronic renal failure: a cardiovascular risk factor. Kidney International. 2005;99:S25-29.

  18. IV. NKF-K/DOQI Clinical Practice Guidelines for Anemia of Chronic Kidney Disease: update 2000. Am J Kidney Dis. Jan 2001;37(1 Suppl 1):S182-238. [Medline].

  19. K/DOQI clinical practice guidelines for chronic kidney disease: evaluation, classification, and stratification. Am J Kidney Dis. Feb 2002;39(2 Suppl 1):S1-266. [Medline].

  20. Kausz AT, Obrador GT, Arora P, Ruthazer R, Levey AS, Pereira BJ. Late initiation of dialysis among women and ethnic minorities in the United States. J Am Soc Nephrol. Dec 2000;11(12):2351-7. [Medline].

  21. Levey AS, Adler S, Caggiula AW, England BK, Greene T, Hunsicker LG, et al. Effects of dietary protein restriction on the progression of advanced renal disease in the Modification of Diet in Renal Disease Study. Am J Kidney Dis. May 1996;27(5):652-63. [Medline].

  22. Lim VS, Kopple JD. Protein metabolism in patients with chronic renal failure: role of uremia and dialysis. Kidney Int. Jul 2000;58(1):1-10. [Medline].

  23. May RC, Mitch WE. Pathophysiology of uremia. In: Brenner BM, ed. Brenner & Rector's The Kidney. Vol 2. 5th ed. Philadelphia, Pa: WB Saunders; 1996:2148-69.

  24. Noris M, Remuzzi G. Uremic bleeding: closing the circle after 30 years of controversies?. Blood. Oct 15 1999;94(8):2569-74. [Medline].

  25. Palmer BF. Sexual dysfunction in uremia. J Am Soc Nephrol. Jun 1999;10(6):1381-8. [Medline].

  26. Roubicek C, Brunet P, Huiart L, et al. Timing of nephrology referral: influence on mortality and morbidity. Am J Kidney Dis. Jul 2000;36(1):35-41. [Medline].

  27. US Renal Data System. Excerpts from the USRDS 2000 Annual Data Report: Atlas of End-Stage Renal Disease in the United States. Am J Kidney Dis. 2000;36 (Suppl 2):S1-S239.

  28. US Renal Data System. USRDS 1999 Annual Data Report. Bethesda, Md: National Institutes of Health; 1999:[Full Text].

  29. Vanholder R. The Uremic Syndrome. In: Greenberg A, ed. Primer on Kidney Disease. 2nd ed. San Diego, Calif: Academic Press; 1998:403-7.

  30. Vanholder R, De Smet R. Pathophysiologic effects of uremic retention solutes. J Am Soc Nephrol. Aug 1999;10(8):1815-23. [Medline].

  31. Vanholder R, De Smet R, Lameire N. Protein-bound uremic solutes: the forgotten toxins. Kidney Int Suppl. Feb 2001;78:S266-70. [Medline].

  32. Walker R. General management of end stage renal disease. BMJ. Nov 29 1997;315(7120):1429-32. [Medline].

  33. Xu X, Fang W, Ling H, et al. Diffusion-weighted MR imaging of kidneys in patients with chronic kidney disease: initial study. Eur Radiol. Sep 30 2009;[Medline].

  34. Yavuz A, Tetta C, Ersoy FF, D'intini V, Ratanarat R, De Cal M, et al. Uremic toxins: a new focus on an old subject. Semin Dial. May-Jun 2005;18(3):203-11. [Medline].

 
Previous
Next
 
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2012 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.