ALAD - Overview: Aminolevulinic Acid Dehydratase (ALAD), Whole Blood

Test Catalog

Test Name

Test ID: ALAD    
Aminolevulinic Acid Dehydratase (ALAD), Whole Blood

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

This test is the preferred test for the confirmation of a diagnosis of aminolevulinic acid dehydratase deficiency porphyria

Genetics Test Information Provides information that may help with selection of the correct genetic test or proper submission of the test request

Aminolevulinic acid dehydratase (ALAD) activity can be inhibited in situations including hereditary tyrosinemia type 1, lead intoxication, and exposure to styrene, trichloroethylene, or bromobenzene. These causes should be ruled out when considering a diagnosis of ALAD deficiency porphyria (ADP). This method will not exhibit a decreased ALAD enzyme activity due to lead intoxication.


Due to longer specimen stability, this test is the preferred test for analysis of ALAD.


This test will not detect lead intoxication.

Testing Algorithm Delineates situations 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 Library of PDFs including pertinent information and consent forms, specimen collection and preparation information, test algorithms, and other information pertinent to test

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

Enzymatic End point/Spectrofluorometric

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


Reporting Name A shorter or abbreviated version of the Published Name for a test; an abbreviated test name

ALA Dehydratase, WB

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

Porphobilinogen (PBG) Synthase
ALAD (Aminolevulinic Acid Dehydratase) Deficiency Porphyria (ADP)
Doss Porphyria