Granular Casts, Urine — Qualitative, Microscopy
Urine microscopy checks for granular casts, small structures that form inside kidney tubules and may be released into the urine.
["Granular casts in urine can reflect kidney-tubule injury or other kidney conditions, but the finding must be interpreted with the rest of the urinalysis."]
Key facts at a glance
- LOINC
- 25160-3
- Short code
- Gran Casts UrnS Ql Micro
- Synonyms
- Gran Casts UrnS Ql Micro
- Category
- liver
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- 0.5 N/A – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- microscopy-light
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test examines urine under a microscope to detect granular casts. Casts are small cylindrical structures that form inside the kidney's filtering tubules and can appear in urine.
Why might I need this test?
Urine cast microscopy may be ordered as part of a kidney or urinary tract evaluation, including assessment for protein in the urine, reduced kidney function, swelling, or changes in urine output. It is often interpreted alongside other urine and blood test results.
How is the test performed?
A urine sample is collected and the sediment is examined under a microscope. The laboratory reports whether granular casts are present; the amount of urine, collection method, and timing of the sample can affect the findings.
How do I prepare for the test?
Follow your clinician's collection instructions and provide a fresh urine sample in the specified sterile container. When directed, collect a clean-catch, midstream sample and deliver it promptly to reduce changes in the urine sediment.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Granular casts may occur with kidney-tubule injury, dehydration, or several other kidney and urinary tract conditions. They are not specific to one diagnosis and should be interpreted with symptoms, urine protein results, kidney function tests, and the rest of the microscopic urinalysis.
Short name
Urine granular casts
Frequently asked questions
What does a urine granular cast mean?
Does one granular cast diagnose kidney disease?
Can I influence the urine sediment result?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy