Bacterial Casts, Urine — Microscopic Examination
A urine microscopy test that looks for bacterial casts, structures sometimes found when bacteria are associated with kidney tissue inflammation.
["Bacterial casts in urine may support an infection involving the kidneys, particularly when other urinary infection symptoms are present."]
Key facts at a glance
- LOINC
- 33784-0
- Short code
- Bacterial casts UrnS Ql Micro
- Synonyms
- Bacterial casts UrnS Ql Micro
- Category
- liver
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 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 a urine sample under a microscope to look for casts containing bacteria. Casts are formed in the kidney's small urine-producing tubules and are released into the urine.
Why might I need this test?
Your clinician may order this test if you have symptoms of a urinary tract infection, such as frequent or painful urination, fever, flank pain, or feeling generally unwell. It can help evaluate whether infection may involve the kidneys rather than only the bladder or urethra.
How is the test performed?
A urine specimen is collected, usually by the clean-catch method, and the laboratory prepares the urine sediment for microscopic examination. The technician reports whether bacterial casts and other urinary findings are present.
How do I prepare for the test?
Follow your clinician's instructions for collecting urine, including washing the genital area and collecting a midstream sample in a sterile container when directed. Tell the laboratory if you recently took antibiotics or if you have urinary symptoms.
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.
◆Associated findings1
Short name
Urinary Bacterial Casts
Frequently asked questions
Are bacterial casts the same as bacteria in a urine culture?
Does finding bacteria in urine always mean I have a kidney infection?
What symptoms should prompt me to seek medical care?
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