Test Id : SUAC
Succinylacetone, Blood Spot
Useful For
Suggests clinical disorders or settings where the test may be helpful
Second-tier newborn screen for tyrosinemia type 1 (HT-1) when primary screen showed nonspecific elevations of tyrosine
Diagnosing HT-1 when used in conjunction with testing for urine organic acids, liver function, alpha-fetoprotein, and molecular genetic analysis of FAH
Genetics Test Information
Provides information that may help with selection of the correct genetic test or proper submission of the test request
This test is a second-tier newborn screen for tyrosinemia type 1.
Method Name
A short description of the method used to perform the test
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Blood Spots
Newborn Screen
Newborn Screening
Succinylacetone
TYR
Tyrosinemia I
Tyrosinemia Type I
Tyr-1
HT-1
Hepatorenal tyrosinemia
Specimen Type
Describes the specimen type validated for testing
Whole blood
Ordering Guidance
The preferred test for diagnosis and monitoring of patients with tyrosinemia type 1 is TYRBS / Tyrosinemia Follow Up Panel, Blood Spot.
Necessary Information
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Submit only 1 of the following specimen types:
Preferred:
Specimen Type: Blood Spot
Supplies: Card - Blood Spot Collection (Filter Paper) (T493)
Container/Tube:
Preferred: Blood Spot Collection Card
Acceptable: Whatman Protein Saver 903 Paper, PerkinElmer 226 filter paper, Munktell filter paper, or blood collected in tube containing EDTA and dried on filter paper.
Specimen Volume: 2 blood spots
Collection Instructions:
1. At least 1 spot should be complete (ie, unpunched).
2. Do not expose specimen to heat or direct sunlight.
3. Do not stack wet specimens.
4. Keep specimen dry.
5. If collection of a new specimen is necessary, let blood dry on the Blood Spot Collection Card (T493) at ambient temperature in a horizontal position for a minimum of 3 hours.
Specimen Stability Information: Ambient (preferred) 7 days/Refrigerated 14 days/Frozen 90 days
Additional Information:
1. For collection instructions, see Blood Spot Collection Instructions
2. For collection instructions in Spanish, see Blood Spot Collection Card-Spanish Instructions (T777)
3. For collection instructions in Chinese, see Blood Spot Collection Card-Chinese Instructions (T800)
Acceptable
Specimen Type: Whole Blood
Container/Tube: Lavender top (EDTA)
Specimen Volume: 2 mL
Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.
Specimen Stability Information: Refrigerate 6 days
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
If not ordering electronically, complete, print, and send a Biochemical Genetics Test Request (T798) with the specimen.
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.
Blood Spot: 1
Whole Blood: 0.5 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Blood spot specimen that shows serum rings or has multiple layers | Reject |
| Insufficient specimen | Reject |
| Unapproved filter papers | Reject |
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 |
|---|---|---|---|
| Whole blood | Varies | ||
Useful For
Suggests clinical disorders or settings where the test may be helpful
Second-tier newborn screen for tyrosinemia type 1 (HT-1) when primary screen showed nonspecific elevations of tyrosine
Diagnosing HT-1 when used in conjunction with testing for urine organic acids, liver function, alpha-fetoprotein, and molecular genetic analysis of FAH
Genetics Test Information
Provides information that may help with selection of the correct genetic test or proper submission of the test request
This test is a second-tier newborn screen for tyrosinemia type 1.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Tyrosinemia type 1 (hepatorenal tyrosinemia, HT-1) is an autosomal recessive condition caused by a deficiency of the enzyme fumarylacetoacetate hydrolase (FAH). HT-1 primarily affects the liver, kidneys, and peripheral nerves, causing severe liver disease, renal tubular dysfunction, and neurologic crises. If left untreated, most patients die of liver failure in the first years of life and all are at risk of developing hepatocellular carcinoma. Treatment with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3 cyclohexanedione (NTBC) is available and is particularly effective when initiated in newborns. The incidence of HT-1 is approximately 1 in 100,000 live births.
While tyrosine can be determined by routine newborn screening, it is not a specific marker for tyrosinemia type I and often may be associated with common and benign transient tyrosinemia of the newborn. Succinylacetone is a specific marker for HT-1 but not consistently measured by newborn screening programs. This assay determines succinylacetone and tyrosine in newborn blood spots by tandem mass spectrometry. Additional follow-up testing may include confirmatory molecular analysis of the FAH gene.
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.
SUCCINYLACETONE
< or =1.0 nmol/mL
TYROSINE
<4 weeks: 40-280 nmol/mL
> or =4 weeks: 25-150 nmol/mL
Interpretation
Provides information to assist in interpretation of the test results
Elevations of succinylacetone (SUAC) above the reference range with or without elevations of tyrosine (TYR) are indicative of tyrosinemia type 1.
Elevations of TYR above the reference range without elevations of SUAC may be suggestive of tyrosinemia type II, type III, transient hypertyrosinemia of the neonate, or nonspecific liver disease.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Normal levels may be seen in affected individuals undergoing treatment.
In rare cases of tyrosinemia type 1, tyrosine or succinylacetone may not be elevated.(1)
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Blackburn PR, Hickey RD, Nace RA, et al. Silent tyrosinemia type I without elevated tyrosine or succinylacetone associated with liver cirrhosis and hepatocellular carcinoma. Hum Mutat. 2016;37(10):1097-1105. doi:10.1002/humu.23047
2. Larochelle J, Alvarez F, Bussieres JF, et al. Effects of nitisinone (NTBC) treatment on the clinical course of hepatorenal tyrosinemia in Quebec. Mol Genet Metab. 2012;107(1-2):49-54
3. Sniderman King L, Trahms C, Scott CR. Tyrosinemia Type I. In: MP Adam, HH Ardinger, PA Pagon et al, eds: GeneReviews [Internet]. University of Washington, Seattle; 2006. Updated May 25, 2017. Accessed December 7, 2023. Available at: www.ncbi.nlm.nih.gov/books/NBK1515/
4. De Jesus VR, Adam BW, Mandel D, Cuthbert CD, Matern D. Succinylacetone as primary marker to detect tyrosinemia type I in newborns and its measurement by newborn screening programs. Mol Genet Metab. 2014;113(1-2)67-75
5. Chinsky JM, Singh R, Ficicioglu C et al. Diagnosis and treatment of tyrosinemia type I: a US and Canadian consensus group review and recommendations. Genet Med. 2017;19(12) doi:10.1038/gim.2017.101
Method Description
Describes how the test is performed and provides a method-specific reference
A 3-mm disk is punched out of the dried blood spot onto a 96-well plate. The amino acids are extracted by the addition of acetonitrile and a known concentration of isotopically labeled amino acids as internal standards. The extract is moved to another 96-well plate, dried under a stream of nitrogen, and derivatized by the addition of n-butanol hydrochloric acid. Analytes are measured by liquid chromatography tandem mass spectrometry. The concentrations of the analytes are established by computerized comparison of ion intensities of these analytes to that of the respective internal standards.(Unpublished Mayo method)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
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.
Monday through 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.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
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.
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- 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.
CPT codes are provided by the performing laboratory.
84510
82542
82542 (if appropriate for government payers)
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 |
|---|---|---|
| SUAC | Succinylacetone, BS | 53231-7 |
| 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.
|
|---|---|---|
| 22714 | Interpretation | 59462-2 |
| 22716 | Reviewed By | 18771-6 |
| 607629 | Succinylacetone | 53231-7 |
| 607630 | Tyrosine | 35571-9 |