Test ID: ALAUR
Aminolevulinic Acid (ALA), Urine
NY State Approved 
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Useful For Suggests clinical disorders or settings where the test may be helpful
Assistance in the differential diagnosis of the various porphyrias
An indicator of lead intoxication in children
Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.
The following algorithms are available in Special Instructions:
-Porphyria (Acute) Testing Algorithm
-Porphyria (Cutaneous) Testing Algorithm
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
Method Name A short description of the method used to perform the test
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Aliases Lists additional common names for a test, as an aid in searching
AIP (Acute Intermittent Porphyria)
ALA (Aminolevulinic Acid)
ALA Dehydratase Deficiency Porphyria (ADP)
DALA (Delta-Aminolevulinic Acid)
Delta-Aminolevulinic Acid
HCP (Hereditary Coproporphyria)
Hereditary Coproporphyria (HCP)
Variegate Porphyria (VP)
VP (Variegate Porphyria)
5-Aminolevulinic Acid
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Container/Tube: Plastic, 10-mL urine tube (Supply T068)
Specimen Volume: 2 mL
Collection Instructions:
1. Patient should abstain from alcohol for 24 hours prior to and during testing.
2. Collect a random urine specimen.
Additional Information: Patient's age is required.
Forms:
1. 1. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (Supply T576) is available in Special Instructions.
2. 2. If not ordering electronically, submit a Biochemical Genetics Request Form (Supply T439) with the specimen.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected
| Hemolysis | NA |
| Lipemia | NA |
| Icterus | NA |
| Other | NA |
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 28 days |
| Frozen | 45 days |
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Aminolevulinic acid (ALA) is formed by the reaction of succinyl-coenzyme A with glycine, which is catalyzed by ALA synthase. This reaction is the first step in the biosynthesis of heme, and is followed by the conversion of ALA to porphobilinogen by ALA dehydratase. End products of heme synthesis are hemoglobin, myoglobin, and the cytochromes, which consist of 4 pyrrole rings connected by methylene bridges and complexed with iron.
The excretion of ALA can be increased either due to inherited deficiencies of enzymes involved in the heme biosynthetic pathway (ALA dehydratase deficiency porphyria, acute intermittent porphyria, hereditary coproporphyria, variegate porphyria) or due to secondary inhibition of ALA dehydratase. Among the secondary causes, acute lead intoxication causes the highest degree of aminolevulinic aciduria. Less significant elevations include chronic lead intoxication, tyrosinemia type I, alcoholism, and pregnancy. For additional information on the recommended order of testing, see Porphyria (Acute) Testing Algorithm and Porphyria (Cutaneous) Testing Algorithm in Special Instructions.
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.
<1 year: < or =10 nmol/mL
1-17 years: < or =20 nmol/mL
> or =18 years: < or =15 nmol/mL
Interpretation Provides information to assist in interpretation of the test results
Elevated values are found in several inherited and acquired conditions that are characterized by various degrees of aminolevulinic aciduria:
-Aminolevulinic acid dehydratase deficiency porphyria
-Acute intermittent porphyria
-Hereditary coproporphyria
-Variegate porphyria
-Intoxication with lead and other heavy metals
-Tyrosinemia type I
-Alcoholism and alcohol induced hepatitis
-Pregnancy
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
The differential diagnosis of aminolevulinic aciduria must be considered on the basis of the patient's clinical presentation.
The preferred test for lead toxicity in children is blood lead (see PBBD/15070 Lead with Demographics, Blood).
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Meyer UA, Schuurmans MM, Lindberg RL: Acute porphyrias: pathogenesis of neurological manifestations. Semin Liver Dis 1998;18:43-52
2. Warren MJ, Cooper JB, Wood SP, Shoolingin-Jordan PM: Lead poisoning, haem synthesis and 5-aminolaevulinic acid dehydratase. Trends Biochem Sci 1998;23:217-221
3. Anderson KE, Sassa S, Bishop DF, et al: Disorders of heme biosynthesis: X-linked sideroblastic anemia and the porphyrias. In The Metabolic Basis of Inherited Disease. 8th edition. Edited by CR Scriver, AL Beaudet, WS Sly, et al. New York, McGraw-Hill Medical Publishing Division, 2001, pp 2991-3062
4. Nuttall KL, Klee GG: Analytes of Hemoglobin Metabolism-Porphyrins, Iron, and Bilirubin. In Tietz Textbook of Clinical Chemistry. Fifth edition. Edited by CA Burtis, ER Ashwood. Philadelphia, WB Saunders Company, 2001, pp 584-607
Method Description Describes how the test is performed and provides a method-specific reference
DALA is determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) stable isotope dilution analysis. The urine is mixed with an internal standard (5-aminolevulinic acid, 13C5, 15N, ALA-IS) and filtered using a 0.2 mcM nylon filter vial. LC-MS/MS is performed using mobile phases composed of methanol/0.1% aqueous formic acid and water/0.1% aqueous formic acid using a Higgins Phalanx C18 column (4.6 x 150 mm) to separate ALA and ALA-IS from the bulk of the specimen matrix. Total analysis time is 15 minutes including column re-equilibration. The MS/MS is operated in the multiple reaction monitoring (MRM) positive mode to follow the precursor to product species transitions 132 to 114 m/z and 138 to 120 m/z for ALA and ALA-IS respectively. The ratios of the extracted peak areas of ALA to ALA-IS determined by LC-MS/MS are used to calculate the concentration of ALA present in the sample.
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Tuesday, Thursday; 8 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
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 The location of the laboratory that performs the test
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's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
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 Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
82135
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
| Result ID | Reporting Name | LOINC Code |
|---|---|---|
| 61547 | Aminolevulinic Acid, U | N/A |
| 34347 | Interpretation (ALA), U | N/A |
| 34348 | Reviewed By | N/A |
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