Test Id : AACYL
Aminoacylase-1 Deficiency, Urine
Useful For
Suggests clinical disorders or settings where the test may be helpful
Follow-up quantitation of abnormal organic acid elevations of N-acetylated amino acids, in particular N-acetylalanine, N-acetylglycine, N-acetylmethionine, and N-acetylglutamic acid
Diagnosis of individuals with aminoacylase-1 deficiency
Evaluating patients with neurologic and psychiatric symptoms of unknown etiology
Highlights
This test provides a quantitative analysis of N-acetyl alanine, N-acetylglycine, N-acetylmethionine, and N-acetylglutamic acid for the diagnosis of aminoacylase-1 deficiency.
Method Name
A short description of the method used to perform the test
Gas Chromatography Mass Spectrometry (GC-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
ACY1
ACY1D
N-acetylated amino acids
N-acetyl amino acids
N-acetyl alanine
N-acetyl glycine
N-acetyl methionine
N-acetyl glutamine
N-acetyl glutamic acid
Specimen Type
Describes the specimen type validated for testing
Urine
Necessary Information
1. Patient's age and sex are required.
2. Include family history, clinical condition (asymptomatic or acute episode), diet, and drug therapy information.
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Supplies: Urine Tubes, 10 mL (T068)
Container/Tube: Plastic, 10-mL urine tube
Specimen Volume: 10 mL
Pediatric: If insufficient collection volume, submit as much specimen as possible in a single container; the laboratory will determine if volume is sufficient for testing.
Collection Instructions:
1. Collect a random urine specimen (first morning void preferred).
2. No preservative.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
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.
3 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
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 | Frozen (preferred) | 90 days | |
| Refrigerated | 60 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Follow-up quantitation of abnormal organic acid elevations of N-acetylated amino acids, in particular N-acetylalanine, N-acetylglycine, N-acetylmethionine, and N-acetylglutamic acid
Diagnosis of individuals with aminoacylase-1 deficiency
Evaluating patients with neurologic and psychiatric symptoms of unknown etiology
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Aminoacylase-1 deficiency (ACY1D) is a very rare autosomal recessive metabolic disorder caused by disease-causing variants in the ACY1 gene and characterized by increased urinary excretion of N-acetylated amino acids, including the derivatives of serine, glutamine, alanine, methionine, glycine, leucine, and valine.(1) The phenotype is variable with less than 20 patients described in the literature. Clinical findings range from asymptomatic to significant neurologic impairments including intellectual disability, seizures, sensorineural hearing loss, and behavioral features such as attention deficit hyperactivity disorder and autism.(2) According to a recent paper, the symptoms described in the literature vary widely, thus making the relationship between clinical symptomatology and ACY1D yet unclear.(3)
For patients with a clinical suspicion of ACY1D, the biochemical diagnosis is established via elevated N-acetylated amino acids in urine. For confirmation, molecular genetic testing of the ACY1 gene is available; order CGPH / Custom Gene Panel, Hereditary, Next-Generation Sequencing, Varies; specify Gene List ID: IEMCP-M9821N.
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.
N-acetylglycine: < or =15.00 mmol/mol creatinine
N-acetyl alanine: < or =10.00 mmol/mol creatinine
N-acetylglutamic acid: < or =20.00 mmol/mol creatinine
N-acetylmethionine: < or =5.00 mmol/mol creatinine
Interpretation
Provides information to assist in interpretation of the test results
When abnormal results are detected, a detailed interpretation is given including an overview of the results and of their significance; a correlation to available clinical information; elements of differential diagnosis; recommendations for additional biochemical testing and in vitro confirmatory studies (enzyme assay, molecular analysis).
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. van Coster R. Aminoacylase I deficiency. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA. eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill Education; 2019. Accessed October 17, 2024. Available at https://ommbid.mhmedical.com/content.aspx?bookid=2709§ionid=225896774
2. Alessandri MG, Milone R, Casalini C, et al. Four years follow up of ACY1 deficient patient and pedigree study. Brain and Dev. 2018;40(7):570-575
3. Smolka V, Friedecky D, Kolarova J, et al. Aminoacylase 1 deficiency: case report on three affected siblings. AME Case Rep. 2023;8:18. doi:10.21037/acr-23-46
4. Sass JO, Mohr V, Olbrich H, et al. Mutations in ACY1, the gene encoding aminoacylase 1, cause a novel inborn error of metabolism. Am J Hum Genet. 2006;78(3):401-409. doi:10.1086/500563
Method Description
Describes how the test is performed and provides a method-specific reference
Urine volumes equivalent to 0.25 to 0.50 mg of creatinine are spiked with the mixture of labeled internal standards, allowed to equilibrate, acidified, and then extracted. After evaporation, the dry residue is derivatized to butyl esters. Specimens are analyzed by capillary gas chromatography mass spectrometry selected ion monitoring using ammonia chemical ionization and a stable isotope dilution method.(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
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.
- 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.
CPT codes are provided by the performing laboratory.
82542
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 |
|---|---|---|
| AACYL | Aminoacylase-1 Deficiency, U | 104695-2 |
| 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.
|
|---|---|---|
| 621432 | Interpretation | 59462-2 |
| 621428 | N-acetylglycine | 104696-0 |
| 621429 | N-acetylalanine | 104697-8 |
| 621430 | N-acetylglutamic acid | 104698-6 |
| 621431 | N-acetylmethionine | 104699-4 |
| 621433 | Reviewed By | 18771-6 |