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Diagnosis of Chronic Kidney Disease

Your doctor will ask about your symptoms and medical history. A physical exam will be done. You will also have a few tests, including:

Blood Urea Nitrogen (BUN) and Creatinine Levels

Creatinine and BUN are waste products that the kidneys usually remove from the blood. When the kidneys are damaged, the creatinine and BUN levels rise in the blood. A simple blood test can measure these levels.

Other Commonly Ordered Blood Tests

  • Complete blood count
  • Calcium, phosphorus, parathyroid hormone
  • Potassium, uric acid, albumin

Urine Protein Level

During the filtering process, the kidneys usually return protein to the circulation. With chronic kidney disease, the kidneys allow protein to leak into the urine. Different kinds of proteins can leak into the urine. Albumin is a protein that often appears in the urine of people who have chronic kidney disease caused by high blood pressure or diabetes.

Different tests can be used to check for protein in the urine.

  • 24-hour urine protein—measures the amount of protein in urine produced over a 24-hour period
  • Dipstick for urine protein—measures the amount of protein in a single urine sample taken first thing in the morning
  • Microalbumin screening in type 1 and type 2 diabetic patients
  • 24-hour urine albumin—measures the amount of albumin in a sample of all urine produced in 24 hours
  • Dipstick for urine albumin—measures the amount of albumin in a single urine sample
  • Protein-to-creatinine ratio—compares the amount of protein to the amount of creatinine in a urine sample
  • Albumin-to-creatinine ratio—compares the amount of albumin to the amount of creatinine in a urine sample

Estimated Glomerular Filtration Rate

The glomerular filtration rate (GFR) is a measurement of how well the kidneys are processing wastes. Your doctor can calculate the GFR based on your:

  • Gender
  • Age
  • Body size
  • Blood creatinine level

The GFR determines the stage of chronic renal disease.

Stage Glomerular Filtration Rate (GFR)
1 Over 90 mL/min (normal)
2 60 to 89 mL/min (mild decrease)
3 30 to 59 mL/min (moderate decrease)
4 15 to 29 mL/min (severe decrease)
5 under 15 mL/min (kidney failure or end-stage renal disease)

Urinary Tract Ultrasound or CT Scan

Your doctor may order an ultrasound or a CT scan to evaluate your kidneys, ureters, and bladder. These tests can tell your doctor if a kidney stone, tumor, or other structural problem may have caused the chronic kidney disease.

Kidney Biopsy

Your doctor may recommend a kidney biopsy, unless you have small kidneys or have end-stage renal disease. During a kidney biopsy, a small piece of kidney tissue is removed and examined under a microscope. The biopsy can tell how much kidney damage has already occurred. It also may determine the cause of your kidney disease.

Special Tests

Your doctor may order the following tests to determine if there is an underlying disease causing your chronic kidney disease:

  • Complements 3 and 4 for possible collagen vascular disease, immune complex disease, or hepatitis C -related disease
  • Antineutrophil cytoplasmic antibody assay for possible vasculitis
  • Protein electrophoresis for possible multiple myeloma


Are you at increased risk for chronic kidney disease? National Kidney Foundation website. Available at: . Published 2010. Accessed July 2, 2013.

Chronic kidney disease. EBSCO DynaMed website. Available at: . Updated April 22, 2013. Accessed July 2, 2013.

Chronic kidney disease: patient information handout. American Academy of Family Physicians website. Available at: . Updated November 2010. Accessed July 2, 2013.

Kidney disease basics. National Kidney Disease Education Program website. Available at: . March 1, 2012. Accessed July 2, 2013.

Johnson CA, Levey AS, et al. Clinical practice guidelines for chronic kidney disease in adults: Part II. glomerular filtration rate, proteinuria, and other markers. Am Fam Phys. 2004; 70:1091-1097.

Snively CS, Gutierrez C. Chronic kidney disease: prevention and treatment of common complications. Am Fam Phys. 2004;70:1921-1930.