Delta-Aminolevulinic Acid

General

Synonym/Acronym:
Delta-ALA, delta-aminolevulinic acid.

Rationale
To assist in diagnosing inherited conditions that disrupt heme synthesis such as acute hepatic porphyria and tyrosinemia, that primarily affect the liver. This study also assists in diagnosing acquired causes that disrupt porphyrin synthesis, such as acute heavy metal poisoning.

Patient Preparation
There are no food, activity, or medication restrictions unless by medical direction. Instruct the patient to avoid alcohol consumption for 24 hours prior to specimen collection; increased ALA excretion is associated with alcohol consumption. Usually, a 24-hr urine collection is ordered but random specimens are accepted. As appropriate, provide the required urine collection container and specimen collection instructions.

Normal Findings
Method: Ion exchange chromatography/Spectrophotometry.

Conventional UnitsSI Units(Conventional units × 7.626)
Amino levulinic acid/random (minimum 2 mL urine)0–4.59 mg/L0–35 µmol/L
Amino levulinic acid/24 hr collection0–8 mg/24 hr0–61 µmol/24 hr

Critical Findings and Potential Interventions
Signs and symptoms of an acute porphyria attack include pain (commonly in the abdomen, arms, and legs), nausea, vomiting, muscle weakness, rapid pulse, and high blood pressure. Possible interventions include medication for pain, nausea, and vomiting, and, if indicated, respiratory support. Initial treatment following a moderate to severe attack may include identification and cessation of harmful drugs the patient may be taking, IV infusion of glucose, and IV heme therapy (hematin, heme arginate) if indicated by markedly elevated urine delta-ALA and porphyrins.

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