Blood Urea Nitrogen-to-Creatinine Ratio
BUN / CR
Description
"Blood Urea Nitrogen-to-Creatinine Ratio" test compares the concentration of urea nitrogen and creatinine in your blood to assess kidney health and hydration status. It’s especially helpful in evaluating whether kidney changes stem from fluid loss, low blood flow, or broader systemic issues. A high ratio may point to dehydration or heart failure, while a low ratio could indicate liver dysfunction. This ratio supports personalized care adjustments and helps guide long-term kidney monitoring and treatment planning.
Category
Waste Metabolites
Procedure
Invasive
Sample Type
Blood – Serum
Units
Ratio
Procedure Category
Blood Draw
Test Group
Complete Metabolic Group, Basic Kidney Group, Complete Kidney Group
Test Group Description
Basic Kidney Group: This group includes tests essential for assessing kidney function and detecting common kidney disorders. Complete Kidney Group: Comprehensive tests provide a thorough assessment of kidney function, yielding detailed insights into renal health and associated conditions. Complete Metabolic Group: A comprehensive suite of tests designed to evaluate metabolic function, offering detailed insights into various aspects of metabolism and associated health conditions.
Optimal Range
For All Individuals:
Conventional Unit: 10.0–16.0 R
SI Unit: Not Applicable
Normal Range
For All Individuals:
Conventional Unit: 10.0–20.0 R
SI Unit: Not Applicable
Results That Differ From The Norm (Direct and Indirect Causes)
Increased levels may indicate:
Dehydration (loss of body water)
Heart failure (inability of the heart to pump blood effectively)
High protein intake
Hyperthyroidism (overactive thyroid gland)
Intestinal bleeding
Kidney diseases
Nephrotoxic substance use (substances harmful to the kidneys)
Urinary tract obstruction
Decreased levels may indicate:
Kidney damage
Liver disease
Malnutrition
Particular prescription uses
Rhabdomyolysis (rapid breakdown of muscle tissue)
Sickle cell anemia (genetic blood disorder)
Key Reasons For Testing
Kidney Function Assessment: Evaluates kidney health by comparing BUN and creatinine levels.
Dehydration Evaluation: A high ratio indicates fluid imbalance, aiding in diagnosis and treatment.
GI Bleeding Screening: Suggests gastrointestinal bleeding when the ratio is elevated, guiding further investigation.
Renal Perfusion Monitoring: Assesses kidney blood flow in critically ill patients to support clinical decisions.
Health Status Conditions It May Be Used To Assess
Currently, this test is not directly associated with any conditions listed on the Health Status page. However, it may be included as part of a broader set of tests linked to specific health conditions.
Some Prominent Medical Labs That May Offer This Test
Please note that this particular test has not been associated with any of the listed prominent medical labs. We recommend enquiring with your private physician or nearest hospital to determine where this specific test can be performed.
References
Important Note
Any medical procedure yielding results outside the norm may be directly or indirectly linked to the conditions outlined on this page. Various factors, including genetics, medication and supplement usage, recent illnesses, pregnancy, pre-test eating, smoking, and stress, can impact the test's outcome. Additionally, factors like false positives, false negatives, inaccurate analyses, and others can influence results.
Reference ranges, which help healthcare professionals interpret medical tests, may vary depending on age, gender, and other factors. They may also differ between laboratories due to variations in instruments and methods used. Optimal ranges are designed for preventive purposes, aiming to identify trends and potential risks early, while normal ranges reflect conventional laboratory values indicating no current disease or pathology. Your healthcare practitioner may have specific reasons for testing that deviate from the usual or may interpret results differently based on individual circumstances. Proper interpretation typically involves considering clinical findings and other diagnostic tests. Hence, it is crucial to provide your healthcare professionals with a comprehensive medical history, consult with them for result interpretation, and follow their guidance for potential re-testing or additional diagnostics.
Disclaimer
This content is provided solely for informative and educational purposes. It is not intended as a substitute for medical advice or treatment from a personal physician. Regarding the interpretation of their medical test results and/or specific health questions, it is recommended that all readers and viewers consult their physicians or other qualified health professionals. The publisher is not responsible for any adverse health effects that may result from reading or following the information in this educational content. Before beginning any nutrition, supplement, or lifestyle program, all viewers, especially those taking prescription or over-the-counter medications, should consult their physician or health care practitioner.
Please note that while prominent lab names are included in this content, we cannot guarantee that these labs offer all the tests mentioned. For confirmation, individuals should contact the labs directly or consult their medical practitioners. The information provided reflects general knowledge at the time of publication and may not include recent updates or emerging research. Readers should verify details with qualified professionals to ensure the most up-to-date and accurate guidance.
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