Documentation of immediate hypersensitivity reactions or diagnosis of patients with systemic mastocytosis. Elevated values are seen in patients with anaphylaxis, with urticaria, or following provocative skin tests.
0.006 - 0.131 mg/24 hour
False negatives may occur if collection of the specimen is not performed near the time of allergic reactions.
4 - 11 days
- HISTAMINE, 24-HOUR, URINE
- Histamine, 24-Hour Urine
Collect 24 hour urine specimen. Add 30 mL of 6 N HCl (10 mL for pediatric patients) to container prior to start of collection. Following collection, mix well, measure 24 hour urine volume, aliquot 4 mL into a plastic urine container and refrigerate. Record total 24 hour urine volume and collection dates/times on request form. Specimens with no preservative are also acceptable: add HCl to container following collection, mix well and send 4 mL aliquot (preferred); alternatively a non-acidified aliquot will be accepted. Patient should void antihistamines, oral corticosteroids, and substances that block H2 receptors for at least 24 hours prior to specimen collection.
Test sent to Mayo Medical Laboratories; performed by Quest Nichols Institute.