Urinary casts are tiny tube-shaped particles that can be found when urine is examined under the microscope during a test called
Urinary casts may be made up of white blood cells, red blood cells, kidney cells, or substances such as protein or fat. The content of a cast can tell your health care provider whether your urine is healthy or abnormal.
Hyaline casts; Granular casts; Renal tubular epithelial casts; Waxy casts; Casts in the urine; Fatty casts; Red blood cell casts; White blood cell casts
How the test is performed
The urine sample you provide may need to be from your first morning urine. The sample needs to be taken to the lab within 1 hour.
How to prepare for the test
No special preparation is needed.
How the test will feel
The test involves only normal urination. There is no discomfort.
Why the test is performed
Your doctor may order this test to see if your kidneys are working properly. It may also be ordered to check for certain conditions such as kidney infections,
There are different types of casts. The presence of a few hyaline casts is normal.
What abnormal results mean
Abnormal results may include:
Fatty casts are seen in people who have lipids in urine, usually as a complication of
Granular casts are a sign of many types of kidney diseases.
Hyaline casts are usually caused by dehydration, exercise, or (water pills) diuretic medicines.
Red blood cell casts are a sign of bleeding into the kidney. They are seen in many kidney diseases.
Renal tubular epithelial cell casts reflect damage to cells in the kidney called tubule cells. These casts are seen in conditions such as
renal tubular necrosis, viral disease (such as CMV nephritis), and kidney transplant rejection.
Waxy casts can be found in persons with advanced kidney disease and
chronic kidney failure.
White blood cell (WBC) casts are more common with acute kidney infections.
Your health care provider will tell you more about your results.
What the risks are
There are no risks with this test.