Initial Testing:

These tests are recommended for evaluating a suspected mast cell disorder patient because they can help rule out other common causes of symptoms and offer other essential information.

Recommended (blood):

Serum tryptase (note when the patient last experienced symptoms)

CBC with differential/platelet

CMP

Lipid panel

Hemoglobin A1C

Hormone panel

Thyroid panel

CRP

Sedimentation rate

IgE panel

Total IgE

Anti-IgE antibodies

ANA

B12

Folate

D 25-hydroxy

PT

PTT/APTT

INR

Chromogranin A

Chronic urticaria index

Protoporphyrin

Anticardiolipin antibodies, quantitative IgG, IgM, IgA

If patient presents with cholesterol deposits in arteries:

Lipoprotein-A (LpA)

If red meat appears to be a trigger:

Galactose alpha 1,3 galactose (Alpha-Gal) IgE

If patient presents with flushing, heart palpitations, sweating:

Metanephrines

Free norepinephrine

add 24 hour urine*: 5-HIAA

Catecholamines

Metanephrines

*if ordering 24 hour urine, the patient may elect to proceed with urine mediator testing. See below.

See interpretation of results.

Mediator testing:

Please note that not all providers, particularly those without access to exceptionally conscientious and well-equipped laboratory services, will choose to run other mediator testing for suspected MCAS patients. This is the third general diagnostic criteria for MCAS, but it is not relevant to diagnosis or staging of systemic mastocytosis and, due to significant limitations both in the percentage of mediators we are currently able to test at all (there are hundreds we cannot) and challenges with handling these extremely sensitive specimens, many successful MCAS patients will never receive laboratory confirmation of increased mediator release. Mast cell mediators degrade extremely quickly.

It's recommended to avoid the use of NSAIDs, PPIs, Vitamin C, and Zileuton for five days prior to testing. Note the care which must be taken with these specimens, and expect the likelihood of false negative results even when these specimens are collected, handled, and processed correctly. When possible, patients are advised to test mediators during periods of increased symptoms. Antihistamines do not affect these tests. Intentional exposure to triggers for the purpose of testing is always inadvisable.

24 hour urine: *Specimen must be kept continuously chilled throughout all phases of collection, shipment, and processing.

N-Methylhistamine

Prostaglandin D2

2,3-dinor 11 prostaglandin F2 alpha

Leukotriene E4

Random urine: *Specimen must be kept continuously chilled throughout all phases of collection, shipment, and processing.

Prostaglandin D2

2,3-dinor 11 beta prostaglandin F2 alpha

N-methylhistamine

Leukotriene E4

Blood: Must be kept continuously chilled, including use of pre-chilled tubes/containers, throughout all phases of collection, shipment, and processing, including refrigerated centrifugation.

Serum heparin*

Plasma heparin*

Plasma histamine

Plasma prostaglandin D2 assay

Chromogranin-A

Serum tryptase (repeat)

*Use most sensitive heparin assay available (lower limit of detection no higher than 0.10 anti-Factor Xa units/ml, ideally lower.)