Creatinine clearance Health Article

What abnormal results mean

Abnormal results are lower-than-normal GFR measurements, and they may indicate:

• Acute tubular necrosis
• Congestive heart failure
• Dehydration
• Glomerulonephritis
• Renal ischemia (blood deficiency)
• Shock
• Acute bilateral obstructive uropathy
• Acute nephritic syndrome
• Acute renal failure
• Chronic renal failure
• End-stage renal disease
• Rapidly progressive (crescentic glomerulonephritis
• Wilms' tumor

What the risks are

The risks of the test are minimal and are related to the blood draw process. Rarely, the following will occur:

• Excessive bleeding at blood draw site
• Fainting or feeling light-headed
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)
• Multiple punctures to locate veins

Special considerations

Factors that may interfere with the accuracy of the test are as follows:

• Incomplete urine collection
• Pregnancy or vigorous exercise

Drugs that can interfere with creatinine clearance measurements include: cimetidine, trimethoprim, and nephrotoxic drugs, such as cephalosporins (cefoxitin).

Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.