Test Catalog

Test Id : TLUCR

Thallium/Creatinine Ratio, Random, Urine

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

Detecting toxic thallium exposure in random urine specimens

Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.

Test Id Reporting Name Available Separately Always Performed
TLUC Thallium/Creat Ratio, U No Yes
CRETR Creatinine, Random, U No Yes

Method Name
A short description of the method used to perform the test

TLUC: Inductively Coupled Plasma Mass Spectrometry (ICP-MS)

CRETR: Enzymatic Colorimetric Assay

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Thallium/Creat Ratio, Random, U

Aliases
Lists additional common names for a test, as an aid in searching

Tl (Thallium)

Specimen Type
Describes the specimen type validated for testing

Urine

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Patient Preparation: High concentrations of gadolinium and iodine are known to interfere with most metal tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for 96 hours.

Supplies: Urine Tubes, 10 mL (T068)

Collection Container/Tube: Clean, plastic urine collection container with no metal cap or glued insert

Submission Container/Tube: Plastic, 10-mL urine tube or a clean, plastic aliquot container with no metal cap or glued insert

Specimen Volume: 7 mL

Collection Instructions:

1. Collect a random urine specimen.

2. See Metals Analysis Specimen Collection and Transport for complete instructions.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.

2.3 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
Frozen 28 days
Ambient 14 days

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

Detecting toxic thallium exposure in random urine specimens

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

Thallium is odorless, tasteless, and found in trace amounts in the earth's crust. It is used in the manufacturing of electronic devices, switches, and closures. It had previously been used in rodenticides. The greatest exposure can occur from eating food (eg, fruits and vegetables) since its easily taken up by plants through the roots. Cigarette smoking is also a source of exposure. Accidental ingestion may lead to vomiting, diarrhea, and leg pains, followed by a severe and sometimes fatal sensorimotor polyneuropathy. Peripheral neuropathy may occur within 1 week of exposure, while hair loss begins and continues for several weeks. Gastrointestinal symptoms, including pain, diarrhea, and constipation have also been reported in acute ingestion, along with myalgias, pleuritic chest pain, insomnia, optic neuritis, hypertension, cardiac abnormalities, Mees lines, and liver injury. Most thallium is excreted in the urine, can be found within an hour after exposure, and can be detected as long as two months after exposure.

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.

THALLIUM:

0-17 years: Not established

> or =18 years: <2 mcg/g creatinine

 

CREATININE:

> or =18 years old: 16-326 mg/dL

Reference values have not been established for patients who are younger than 18 years of age.

Interpretation
Provides information to assist in interpretation of the test results

Patients exposed to high doses of thallium (>1 g) present with alopecia, peripheral neuropathy, and seizures, and kidney failure.

 

Normal daily thallium excretion is less than 1 mcg/day.

 

Exposed patients can have urine thallium excretion greater than 10 mcg/day. The long-term consequences of such an exposure are poor.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

No significant cautionary statements

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Bank WJ, Pleasure DE, Suzuki K, Nigro M, Katz R. Thallium poisoning. Arch Neurol. 1972;26(5):456-464. doi:10.1001/archneur.1972.00490110090009

2. Pelclova D, Urban P, Ridson P, et al. Two-year follow-up of two patients after severe thallium intoxication. Hum Exp Toxicol. 2009;28(5):263-272. doi:10.1177/0960327109106487

3. Zhao G, Ding M, Zhang B, et al. Clinical manifestations and management of acute thallium poisoning. Eur Neurol. 2008;60(6):292-297. doi:10.1159/000157883

4. Strathmann FG, Blum LM. Toxic elements. In: Rifai N, Chiu RWK, Young I, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:455.e55

5. Campanella B, Colombaioni L, Benedetti E, et al. Toxicity of thallium at low doses: A review. Int J Environ Res Public Health. 2019;16(23):4732. doi:10.3390/ijerph16234732

Method Description
Describes how the test is performed and provides a method-specific reference

The metal of interest is analyzed by inductively coupled plasma mass spectrometry.(Unpublished Mayo method)

 

Creatinine:

The enzymatic method is based on the determination of sarcosine from creatinine with the aid of creatininase, creatinase, and sarcosine oxidase. The liberated hydrogen peroxide is measured via a modified Trinder reaction using a colorimetric indicator. Optimization of the buffer system and the colorimetric indicator enables the creatinine concentration to be quantified both precisely and specifically.(Package insert: Creatinine plus ver 2. Roche Diagnostics; V15.0, 03/2019)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Tuesday, Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

2 to 5 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

83018

82570

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
TLUCR Thallium/Creat Ratio, Random, U 13469-2
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
CRETR Creatinine, Random, U 2161-8
615256 Thallium/Creat Ratio, U 13469-2

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports