Tryptase test is the most accurate test for diagnosing severe allergies and mast cell diseases

Has your doctor recommended a Tryptase test?
If you're experiencing symptoms of a severe allergic reaction or your doctor suspects a rare immune system disorder, this test may be ordered. The Tryptase test is a valuable tool used to help diagnose serious immune-related conditions.In this article from Dalili Medical, we’ll explain everything you need to know about the Tryptase test:
What is it? Why is it done? How is it performed? And what do the results mean?

✅ What Is the Tryptase Test?

The Tryptase test is a blood test used to measure the level of an enzyme released by specific immune cells called mast cells. These cells play a key role in the body’s immune response, especially during severe allergic reactions (anaphylaxis) and some rare immune disorders.

Elevated tryptase levels in the blood may indicate:

• A severe allergic episode

• Rare mast cell-related disorders such as mastocytosis

 When Is the Tryptase Test Ordered?

Doctors may request a tryptase test in the following situations:

• After a severe allergic reaction or anaphylactic shock

• If a mast cell disorder is suspected

• To help diagnose conditions such as:

  • Mastocytosis (abnormal buildup of mast cells)

  • Mast Cell Activation Syndrome (MCAS)

• To investigate symptoms like:

  • Chronic skin rashes

  • Unexplained itching

  • Sudden drops in blood pressure

 How Is the Test Performed?

• A simple venous blood sample is drawn from the arm.

• In emergency situations (e.g., after an allergic reaction):

  • The blood should ideally be collected within 1 to 4 hours of symptom onset.

• For chronic evaluation:

  • The test is taken during a stable period, when no acute symptoms are present.

 Normal Tryptase Levels

Levels may vary slightly by lab, but typically:

• Normal range: Less than 11.4 ng/mL

• Mild elevation: May indicate temporary mast cell activation

• Persistent elevation: Could suggest conditions like mastocytosis

❗ What Do the Results Mean?

✅ Normal Level:

• Usually indicates no significant immune activation.

• However, it does not rule out allergy completely, especially if symptoms have already resolved.

❗ Temporarily Elevated:

• Often indicates a severe allergic reaction (e.g., anaphylaxis).

• Levels usually return to normal within 24 to 48 hours.

 Persistently Elevated:

May suggest:

• Mastocytosis

• Mast Cell Activation Syndrome (MCAS)

• Rare cancers such as myeloid leukemia

 Difference Between Anaphylaxis and Mastocytosis

❓ Frequently Asked Questions

Do I need to fast before the tryptase test?
❌ No, fasting is not required.

Can the test be done after symptoms improve?
It’s best performed within 4 hours of the onset of symptoms, but it can also be repeated later if necessary.

Is one test result enough for a diagnosis?
❌ No. The result must be evaluated alongside symptoms and may require additional tests like skin biopsies or KIT D816V mutation testing in suspected mastocytosis.

Is a high tryptase level always dangerous?
Not necessarily, but it requires careful evaluation to determine the underlying cause.

✍️ Summary

The Tryptase test is a specialized blood test that helps diagnose mast cell-related conditions such as anaphylaxis and mastocytosis.
Elevated levels may be temporary due to allergic reactions or persistent in chronic disorders.
If your doctor has ordered this test, timing is important, and it’s crucial to follow up with an immunologist or allergy specialist to interpret the results accurately.