GDCRU - Clinical: Gadolinium/Creatinine Ratio, Random, Urine

Test Catalog

Test ID: GDCRU    
Gadolinium/Creatinine Ratio, Random, Urine

Useful For Suggests clinical disorders or settings where the test may be helpful

An aid in documenting past exposure to gadolinium-containing chelates and to monitor the effectiveness of dialysis

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Gadolinium is a member of the lanthanide series of the periodic table of elements and is considered a nonessential element. Due to its paramagnetic properties, chelated gadolinium is commonly employed as contrast media for magnetic resonance imaging and computer tomography scanning.


Gadolinium is eliminated primarily by renal filtration. In healthy subjects with normal renal function, the plasma half-life of gadolinium is approximately 90 minutes. Patients with reduced renal function exhibit an increased gadolinium excretion half-life.


Gadolinium has been associated with the nephrogenic systemic fibrosis in patients with impaired renal function. In this syndrome, prolonged retention of gadolinium is thought to allow the gadolinium cation to dissociate from its synthetic organic chelator and deposit predominantly in the skin, although other organs may be affected as well. These patients are often severely debilitated by progressive skin thickening and tightening. Fibrosis of skeletal muscle, lungs, liver, testes, and myocardium have all been observed, often with fatal results. Because the ionic radius of gadolinium (3+) is similar to that of calcium (2+), it may also deposit in bone.


Three hemodialysis treatments are required to substantially remove gadolinium from patients with impaired renal function; peritoneal dialysis is not effective.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

0-17 years: not established

> or =18 years: <0.8 mcg/g creatinine

Interpretation Provides information to assist in interpretation of the test results

Elevated gadolinium (>0.7 mcg/g creatinine) observed in a random urine specimen collected more than 96 hours after administration of gadolinium-containing contrast media may indicate impaired ability to eliminate gadolinium or continued exposure, suggesting either reduced renal function or exposure to anthropogenic sources. Patients with reduced renal function who have been exposed to gadolinium may have an increased risk to develop nephrogenic systemic fibrosis.


The normal value is less than 0.8 mcg/g creatinine; 95% of unexposed patients will have values below 0.1 mcg/g creatinine. The lower limit of detection is 0.1 mcg/g creatinine.

Supportive Data

An evaluation of urine gadolinium concentration in healthy human subjects not exposed to gadolinium within 96 hours of specimen collection generated a reference range of less than 0.7 mcg/g creatinine (median value 0.2 mcg/g creatinine) with no evidence of age or gender trend. Urine gadolinium concentrations observed in Mayo Clinic patients with nephrogenic systemic fibrosis (NSF), either before or after chelation therapy with succimer, were in the range of 2 to 5 mcg/g creatinine (ie, succimer had no effect on excretion rate). No peer-reviewed reports of urine gadolinium concentrations associated with NSF were found on literature search.

Clinical Reference Provides recommendations for further in-depth reading of a clinical nature

1. D'Hease P, De Broe M: Gadolinium. In Handbook on Metals in Clinical and Analytical Chemistry. Edited by HG Seiler, A Sigel, H Sigel. Marcel Dekker, Inc, New York, 1994, pp 365-369 

2. Swan SK, Lambrecht LJ, Townsend R, et al: Safety and pharmacokinetic profile of gadobenate dimeglumine in subjects with renal impairment. Invest Radiol 1999;34:443-448 

3. Otherson JB, Maize JC, Woolson RF, Budisavljevic MN: Nephrogenic systemic fibrosis after exposure to gadolinium in patients with renal failure. Nephrol Dial Transplant 2007;10:1093-1100

4. Perazella MA: Nephrogenic systemic fibrosis, kidney disease, and gadolinium: is there a link? Clin J AM Soc Nephrol 2007;2:200-202

5. Saitoh T, Hayasaka K, Tanaka Y, et al: Dialyzability of gadodiamide in hemodialysis patients. Radiat Med 2006;24:445-451

6. Leung N, Pittelkow MR, Lee CU, et al: Chelation of gadolinium with deferoxamine in a patient with nephrogenic systemic fibrosis. NDT Plus 2009;2(4):309-311

7. Girardi M, Kay J, Elston DM, et al: Nephrogenic systemic fibrosis: Clinicopathological definition and workup recommendations. J Am Acad Dermatol 2011;65:1095-1106

8. Telgmann L, Sperling M, Karst U: Determination of gadolinium-based MRI contrast agents in biological and environmental samples: A review. Analytica Chimica Acta 2013;764:1-16

Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test

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