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Total Homocysteine/Creatinine Ratio, 24-Hour Urine — Calculated Substance Ratio

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

Measures homocysteine relative to creatinine in urine collected for 24 hours. The ratio helps account for variations in urine concentration.

Quick summary

["This test measures how much homocysteine is excreted in urine compared with creatinine, which helps evaluate homocysteine metabolism."]

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

Key facts at a glance

LOINC
25929-1
Short code
(Hcys)2/Creat 24h Ur-sRto
Synonyms
(Hcys)2/Creat 24h Ur-sRto
Category
kidney
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
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 measures homocysteine and creatinine in a 24-hour urine collection. The laboratory may calculate a homocysteine-to-creatinine ratio, which can help reduce the effect of differences in urine concentration.

Why might I need this test?

It may be used to evaluate increased urinary homocysteine or suspected problems with homocysteine metabolism. Your clinician will interpret it along with your symptoms, medical history, and other laboratory tests.

How is the test performed?

You collect all urine for a full 24-hour period in the container provided by the laboratory. The collection is then delivered for measurement of homocysteine and creatinine, and a ratio may be calculated.

How do I prepare for the test?

Follow the laboratory's collection instructions carefully, including the exact start and stop times. Do not change your diet or take supplements unless your clinician directs you to, and ask whether the container should be refrigerated during collection.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

24-Hour Urine Homocysteine/Creatinine Ratio

Frequently asked questions

Why is a creatinine ratio included?
Creatinine helps show how concentrated the urine is. Comparing homocysteine with creatinine can make the homocysteine result less dependent on variations in urine concentration.
How should the 24-hour urine collection be done?
Collect all urine during the exact 24-hour period specified by the laboratory, including urine produced at the end of the period. If you miss a collection or spill urine outside the container, contact the laboratory for instructions.
Do I need to change my diet before this test?
Do not make major diet or supplement changes unless your clinician tells you to. Because vitamins and other factors can affect homocysteine, tell the laboratory about relevant supplements and medications.
  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