Citrulline
CIT
Description
"Citrulline" test measures citrulline levels in your blood, an amino acid involved in nitrogen removal and nitric oxide production. It’s often ordered when doctors suspect urea cycle disorders, intestinal damage, or issues related to poor nutrient absorption. Abnormal levels may signal impaired enzyme activity, mitochondrial dysfunction, or gastrointestinal problems. This test is helpful for diagnosing causes of low energy, muscle weakness, or digestive symptoms. Based on results, your doctor may recommend dietary adjustments, supplements, or further metabolic evaluation.
Test Category
Amino Acids
Procedure
Invasive
Sample Type
Blood – Plasma
Units
Micromoles Per Liter
Procedure Category
Blood Draw
Test Group
Amino Acid Group
Test Group Description
Amino Acid Group: Tests in this group analyze amino acid levels in the body, providing valuable insights into protein metabolism and potential genetic or metabolic disorders related to amino acid processing.
Optimal Range
For All Individuals:
Conventional Unit: 18–57 µmol/L
SI Unit: 18–57 µmol/L
Normal Range
For All Individuals:
Conventional Unit: 13.7–63.2 µmol/L
SI Unit: 13.7–63.2 µmol/L
Results That Differ From The Norm (Direct and Indirect Causes)
Increased levels may indicate:
Argininosuccinic aciduria (a rare genetic disorder affecting the urea cycle)
Crohn's disease (an inflammatory bowel disease affecting the digestive tract)
Hepatic failure (Liver dysfunction)
Ornithine transcarbamylase deficiency (an inherited disorder of the urea cycle)
Short-bowel syndrome (a condition resulting from the...
Key Reasons For Testing
Evaluation of Intestinal Health: Measures citrulline levels to assess small intestine function.
Assessment of Liver Function: Checks citrulline’s role in the urea cycle and liver waste clearance.
Monitoring Renal Function: Detects changes in citrulline levels to evaluate kidney performance.
Detection of Urea Cycle Disorders: Identifies abnormalities in the urea cycle, such as citrullinemia.
Assessment of Arginine Production: Evaluates citrulline’s role in arginine synthesis, a critical amino acid.
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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