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Urine Microscopic Examination (Crystals)

Published: August 9, 2026Updated: August 16, 2026

This test examines your urine under a microscope to identify and count certain crystals that may form naturally or due to medical conditions.

Quick summary

["Helps detect potential kidney or urinary tract issues by spotting abnormal crystals."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
38459-4
Short code
Crystals #/area UrnS HPF
Synonyms
Crystals #/area UrnS HPF
Category
chemistry
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
microscopy-light-hpf
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

Why This Test Is Done

Doctors may order this test if you have symptoms like pain or discomfort while urinating, frequent urination, blood in urine, or if you’re experiencing kidney stones or other urinary issues. It can also be part of routine checks for certain kidney-related conditions.

What to Expect During the Test

You’ll provide a urine sample, typically collected in the morning. The sample is then examined under a microscope to look for crystals, cells, or other abnormalities.

Common Crystals Found and Their Possible Meanings

Crystals like calcium oxalate, urate, or cystine can appear in urine and may indicate conditions such as kidney stones, metabolic disorders, or infections. Their presence doesn’t always mean a problem, but it warrants further evaluation.

Preparation and Tips

No special preparation is needed. Ensure your urine sample is fresh and uncontaminated. If you’re taking certain medications or have a known condition, inform your healthcare provider before the test.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Urine Microscopy for Crystals

Frequently asked questions

Urine crystals can signal underlying health issues, such as kidney stones, metabolic imbalances, or infections. They may also help diagnose conditions like gout, cystinuria, or other kidney-related disorders. Always discuss results with your doctor for personalized interpretation.
This test is often used as a screening or diagnostic tool but isn’t always definitive on its own. If crystals are found, additional tests may be needed to determine the cause.
Will I need to repeat this test if I have abnormal results?
Yes, your doctor may recommend repeating the test or ordering further tests to investigate the cause of the crystals. Results depend on the type and quantity of crystals found, so follow-up is often necessary.
Can diet or medications affect urine crystals?
Yes, certain foods (like high-oxalate foods), medications, or dehydration can influence urine crystal formation. Your doctor may suggest dietary changes or adjustments to your medication if crystals are a concern.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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 16, 2026. · Read our editorial policy