Aminolevulinic Acid Dehydratase (ALAD), Blood
Also known as: ALA DEHYD
Use
The Aminolevulinic Acid Dehydratase (ALAD) test is used to confirm a diagnosis of aminolevulinic acid dehydratase deficiency porphyria (ADP), an extremely rare porphyria. It measures the activity of the erythrocyte enzyme ALAD, which plays a critical role in the heme synthesis pathway. Deficiency in this enzyme leads to accumulation of its substrates and subsequent symptoms of porphyria, primarily neurovisceral attacks. This test is not suitable for lead intoxication evaluation as lead inhibits ALAD enzymatic activity.
Special Instructions
Patient should abstain from alcohol for 24 hours prior to collection. Include a list of medications the patient is currently taking on the request form. For New York clients, informed consent is required and should be documented on the form or electronic order.
Limitations
This test is not directly performed at ARUP Laboratories; it is sent to an external reference lab. It is not useful for evaluating lead intoxication as the assay can reactivate ALAD that has been inhibited by lead exposure. Proper storage and transportation of the blood sample are crucial as ALAD activity is rapidly degraded otherwise. In cases of suspected lead poisoning, alternative diagnostic methods should be pursued.
New York Approved
Methodology
Other
Biomarkers
LOINC Codes
- 12916-3
- 59462-2
- 18771-6
Result Turnaround Time
5-11 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
4 mL
Minimum Volume
3 mL
Container
Green (sodium heparin), Lavender (EDTA), or Green (lithium heparin) tube
Patient Preparation
Patient should abstain from alcohol for 24 hours prior to collection.
Storage Instructions
Refrigerate as soon as possible after collection.
Causes for Rejection
Grossly hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 days |
| Refrigerated | 1 week |
| Frozen | Unacceptable |