If there is any reason to suspect a mast cell disorder, but your patient is not on treatment and does not yet have a diagnosis:

1. First, do no harm.

A) Delay non-emergency procedures of all kinds. (most especially invasive procedures or those involving the need for medical implants or new dental materials, those requiring pain management, and lower gastrointestinal scopes)

B) Delay non-emergency radiology or other potentially triggering testing. (most especially higher radiation tests or any tests with contrast or other ingested or injected agents of any kind. Prescribe premedication when any radiology is necessary.)

C) Avoid skin allergy testing, and direct the patient to reject this if offered by other practitioners.

D) If the patient is taking a beta antagonist and you are at the beginning of this process, find a suitable alternative today.

E) If a patient is taking a drug with a relative contraindication (see list in emergency protocols), evaluate this need and relative risk.

F) With whatever you prescribe, try to follow the low, slow, and one at a time “rules” of mast cell disorder patients and expect reactions to excipients.

2. If you have not already, perform a physical examination and take a detailed medical history. (See checklist.)

3. Prescribe rescue medications and direct the patient as to when and how to use them.

   Suitable epinephrine auto-injector or alternative

Recommend first generation H1 antagonists like diphenhydramine (benadryl) and, if necessary, other options listed in Treatment.

4. Begin trials of firstline treatments. (See this page.) Note that for many patients, these and other medications may require compounding in particular excipients.

5. Testing: Step 1 (See interpretation.)

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 the practitioner and patient may elect to proceed with urine mediator testing, which MUST BE CONSISTENTLY CHILLED THROUGHOUT ALL PHASES OF COLLECTION, SHIPPING, AND PROCESSING. Avoid use of NSAID's, PPI's, Zileuton, and Vitamin C 5 days prior to testing. Please again note the extreme level of care which must be taken with these specimens and expect the likelihood of false negative results even when these specimens are collected, processed, and handled correctly during or shortly after a reaction. When possible, patients are advised to test mediators during periods of increased symptoms. Antihistamines do not affect these results. Intentional exposure to triggers for the purpose of testing is never recommended.

24 hour urine:

N-Methylhistamine

Prostaglandin D2

2,3-dinor 11 prostaglandin F2 alpha

Leukotriene E4

Random urine:

Prostaglandin D2

2,3-dinor 11 beta prostaglandin F2 alpha

N-methylhistamine

Leukotriene E4

See mediator testing for the inclusion of blood tests.