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April 2017

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 11

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

19. How do other conditions affect mast cell disease?
• Mast cell activity can affect literally every system in the body.
• Mast cells are found throughout the body and live in many tissues and organs in significant numbers.
• There are essentially three types of damaging mast cell activity:
–Normal mast cells are getting bad signals from other cells and they do bad things. This is not mast cell disease because these mast cells are not broken. They are getting signals from other broken cells.
–Abnormal mast cells do bad things and tell other nearby cells to do bad things. This is mast cell disease, specifically mast cell activation syndrome and sometimes monoclonal mast cell activation syndrome.
–You make way too many mast cells, they are abnormal, they do bad things, and they tell other nearby cells to do bad things. This is mast cell disease, specifically all forms of mastocytosis (systemic, cutaneous, and mast cell leukemia), sometimes monoclonal mast cell activation syndrome and mast cell tumors (mastocytoma and mast cell sarcoma).
• Generally speaking, if you have mast cell disease, any other condition you have will irritate your mast cell disease. This can also work the other way around and mast cell disease can irritate your other conditions.
• Many conditions naturally trigger higher level mast cell activation.
• Any disease that causes your body to make a lot of cells very quickly is likely to trigger to mast cell activation. Cancers are mast cell activating. Non cancerous diseases where you make too many blood cells at once, like polycythemia vera or essential thrombocythemia, are are mast cell activating.
• Mast cells are usually found very close to tumors. Sometimes, they are found inside tumors. Mast cells are important for tumors to survive because they can make blood vessels to bring tumors the blood they need.
• Diseases affecting the immune system are triggering to mast cells. In fact, many patients have mast cell activation syndrome caused by the immune disease irritating their mast cells so much. Many mast cell patients have autoimmune diseases like lupus or rheumatoid arthritis. Many patients also have deficiencies in their immune system. Because mast cells are immune cells, they are very responsive to signals from other immune cells. Mast cells think those cells need help from them to fight an infection or disease so they respond strongly to “help”.
• Diseases that cause inflammation also trigger mast cells. This can happen whether the inflammation is local or not. Systemic inflammation is more irritating to mast cells since that kind of inflammation can find more mast cells throughout the body. Local inflammation can irritate mast cells nearby. It can also call mast cells from other parts of the body to that location.
• Mast cells are actively involved in fighting infections from viruses, bacteria, fungi, and parasites. This is the reason many mast cell patients find they are more reactive when they have even a minor illness, like a cold.
• Any type of physical stress can activate mast cells. This can be something as simple as exercise or something more traumatic such as a car accident, a surgery, or childbirth. Even things that should be easy to recover from can activate mast cells, like a small cut, dehydration, or getting overheated. This also includes stress caused by another disease.
• Emotional stress can activate mast cells, even if the big emotion is joy.
For more detailed reading, please visit this page:

Symptoms and effects of mast cell disease

 

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 10

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

17. Does mast cell disease impact mood, anxiety, and depression?
• Yes. This has been described in literature for over 30 years. In 1986, a paper described a series of patients with systemic mastocytosis who had severe psychiatric symptoms as a result of their disease. It was called “mixed organic brain syndrome”.
• Depression, anger, bipolar disorder, attention deficit disorders, anxiety, irritating, and panic disorders have all been associated with mast cell disease.
• One study found that in a group of patients with cutaneous mastocytosis and systemic mastocytosis, 75% of the patients had symptoms of depression. In another study, 60% had symptoms of depression or anxiety.
• Many patients have been diagnosed with a psychiatric condition before learning that they have mast cell disease. For many mast cell patients, managing their diseases lessens the severity of their psychiatric symptoms. Antihistamines have been reported many times to improve these symptoms.
• Mast cells are often sitting right next to nerve cells throughout the body. Mast cells are found in large numbers in the brain. Chemicals released by mast cells can cause psychiatric symptoms.
• Some of the chemicals released by mast cells are specifically intended to talk to nerve cells. Histamine is one such chemical. When histamine is not released in the right amounts at the right times, it can affect how other chemicals are released. Some of these chemicals are also for cells to talk to nerves, like serotonin and dopamine. Mast cells can also release serotonin.

18. Are medications for depression, anxiety or other psychiatric conditions used in mast cell patients?
• Yes. As with every medication, only you and your care team can decide if a medication is safe for you. No medication is universally safe or always dangerous.
• Benzodiazepines are usually well tolerated in mast cell patients. Benzodiazepines actually interact with mast cells and can make them release fewer chemicals. (Be aware that the IV forms of these medications sometimes have alcohol in them).
• SSRIs are sometimes taken by mast cell patients. Mast cell patients should be cautious because they can increase serotonin levels and mast cells can also release serotonin.
• Tricyclic antidepressants are more commonly used in mast cell patients. Tricyclic antidepressants actually work as antihistamines, too.
• Other drugs that can manage psychiatric symptoms, like mirtazapine, olanzapine, and quetiapine, also have antihistamine properties.
For more detailed reading, please visit these posts:

 

Neuropsychiatric features of mast cell disease: Part 1 of 2

Neuropsychiatric features of mast cell disease: Part 2 of 2

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 9

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

15. How is mast cell disease treated?
• There are a number of medications to treat mast cell disease. Mast cells release so many chemicals, some in a large quantity. We are not able to totally stop mast cells from releasing the chemicals so we need to use many medications to block their effects on the body.
• The baseline regimen for mast cell patients include antihistamines and mast cell stabilizers. Specifically, patients are usually prescribed two antihistamines that work two different ways. These are called H1 antihistamines and H2 antihistamines. The H in these meds stand for histamine. There are many antihistamine options. Antihistamines stop the histamine from working in the body. Even still, many patients experience histamine driven symptoms
• Mast cell stabilizers work by making mast cells less likely to release chemicals. There are fewer options for mast cell stabilizers. Cromolyn is a very common mast cell stabilizer. Ketotifen is both a mast cell stabilizer and an antihistamine. Ketotifen that you can take as a pill is not approved in the US because there was not a market for it so it was never submitted to the FDA. However, patients can get ketotifen in pill form through compounding pharmacies in the US.
• Other types of medication commonly used for mast cell disease that block the effect of mast cell chemicals include leukotriene inhibitors and PAF blockers.
• Some medications can stop mast cells from making specific chemicals. These include COX inhibitors, lipoxygenase inhibitors, and corticosteroids like prednisone.
• Many patients are deficient in some vitamins or minerals because they don’t absorb them well in the GI tract. Vitamin D and iron are commonly low. Patients often take supplements to replace these deficiencies.
• Chemo drugs are sometimes used to treat severe mast cell disease. These drugs can kill mast cells and/or decrease the amount of chemicals released.
• IV fluids are reported by patients to help with symptoms such as fatigue and swelling.
• There are many other medications that can be used to treat other symptoms.

16. Do I have to take medication if I feel okay?
• Mast cell patients are usually recommended to take baseline medications like antihistamines and mast cell stabilizers even if they feel okay. This is for two main reasons: mast cells can damage your body even if you don’t feel it; and if you do not take baseline medications, you will have less protection from a severe reaction and anaphylaxis.
• Many patients have other medications prescribed to be taken as needed. These medications are given when symptoms are bad and do not necessarily have to be taken daily.
• Please speak with your provider to clarify what meds are taken as needed and what meds are taken every day.
For more detailed reading, please visit these posts:

The Provider Primer Series: Management of mast cell mediator symptoms and release

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, part 8

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

14. Are there any special instructions for the tests to diagnose mast cell disease?
• There are a lot of tests used to diagnose mast cell disease. There are certainly people who slip through the cracks with the current diagnostic criteria.
• Remember this as you read the following: DO NOT, UNDER ANY CIRCUMSTANCES, EVER, DISCONTINUE MEDICATION FOR TESTING WITHOUT EXPLICIT INSTRUCTIONS TO DO FROM A DOCTOR THAT UNDERSTANDS MAST CELL DISEASE. Stopping medications for mast cell disease can be very dangerous.
• The biopsy forms the centerpiece of diagnosis of both cutaneous and systemic forms of mastocytosis.
• You can increase your chance of positive skin biopsy by choosing either a permanent lesion or an area of skin that is frequently reactive.
• For internal organs, including bone marrow, you can’t always tell where to biopsy just by looking. The area may look normal but show inflammation when viewed with a microscope.
• If patients do not need to take daily corticosteroids because they do not make their own (adrenal insufficiency or Addison’s disease), they are often recommended to not use corticosteroids (prednisone or similar) for five days before a bone marrow biopsy. Taking corticosteroids can tell your body to make a lot of extra white blood cells which can make it harder to give a correct diagnosis.
• The CKIT D816V mutation test is often done on a blood sample. It is much more accurate when a bone marrow biopsy is tested because there are many more mast cells. Mast cells do not live in the blood so the blood test is less accurate. If the test is positive in blood, we assume that the patient is truly positive. If the test is negative in blood, we are not sure if the patient is truly negative.
• Serum tryptase is a test with a lot of caveats. It is influenced heavily by timing and patient factors like weight. Many people with mast cell disease have normal serum tryptase. It is good for tracking progression of disease in patients with systemic mastocytosis.
• About 85% of patients with systemic mastocytosis have a baseline tryptase value over 20 ng/mL. Patients with monoclonal mast cell activation syndrome may also have baseline tryptase value over 20 ng/mL. For these patients, they should have two different tests from days when they are not especially reactive, or have had anaphylaxis.
• For patients with mast cell activation syndrome, we are often looking for an increase in tryptase during a reaction or anaphylactic event. In these patients, experts recommend having blood drawn 15 minutes to 4 hours after onset of the event.
• Another sample should be drawn 1-2 days later so that you have a sample to compare with the tryptase level during the event. Many experts accept a level increased by 20% plus 2 ng/mL above the baseline to be indicative of mast cell activation. (I made a typo on this that said 20% to 2 – sorry!)
• As we have previously discussed, many mast cell mediators should be kept cold because they break down quickly. 24 hour urines for n-methylhistamine, prostaglandin D2, 9a,11b prostaglandin F2, and leukotriene E4 should be kept cold.
• Performing a 24 hour urine when you are having a reaction event can increase the likelihood of mediator release.
• COX inhibitors will interfere with prostaglandin production. Some patients stop these meds before giving 24 hour urines for prostaglandin testing. DO NOT STOP MEDS WITHOUT BEING ADVISED BY AN EXPERIENCED MAST CELL PROVIDER.
• Lipoxygenase inhibitors will interfere with leukotriene production. Some patients stop these meds before giving 24 hour urines for leukotriene testing. DO NOT STOP MEDS WITHOUT BEING ADVISED BY AN EXPERIENCED MAST CELL PROVIDER.
• Heparin is very heat sensitive. Plasma heparin must be kept cold. One study reported that a tourniquet on the upper arm for ten minutes before drawing the sample increased the change of detecting mast cell activation with this test.
• Chromogranin A is influenced by many other conditions and medications. It is important that those other conditions be ruled out. This may require lengthy body scans and other tests. Chromogranin A is influenced by proton pump inhibitors, meds that are commonly taken by mast cell patients. DO NOT STOP MEDS WITHOUT BEING ADVISED BY AN EXPERIENCED MAST CELL PROVIDER.

For more detailed reading, please visit these posts:

The Provider Primer Series: Mediator testing

Patient questions: Everything you wanted to know about tryptase

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, part 7

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

 

13. What do these biopsy tests look for?
• They look for the shape, quantity, and distribution of mast cells.
• They also look for specific proteins on the outside of mast cells and tissue damage around mast cells.
• Systemic mastocytosis and cutaneous mastocytosis are generally diagnosed by biopsy. With very, very few exceptions, you cannot meet the criteria for systemic mastocytosis without having a positive biopsy. Sometimes people with monoclonal mast cell activation syndrome are diagnosed by having a biopsy that looks like a very early phase of systemic mastocytosis.
• The diagnostic criteria for mast cell activation syndrome are hotly contested. Most doctors do not use biopsies to diagnose MCAS because there are not uniform criteria. Some doctors feel that more than 20 mast cells in a field when you look through the microscope is a sign of MCAS.
• Cutaneous mastocytosis is having too many broken mast cells in your skin. For this condition, they are looking for either 20 mast cells to be present in the microscope field (hpf) when looking at the skin, or for there to be at least one cluster of at least fifteen mast cells.
• Clustering is a very important feature of mastocytosis. When mast cells bunch together in a cluster, it is easier to damage the tissue. They are essentially punching holes in the tissue by clustering.
• Systemic mastocytosis is having too many broken mast cells made by the bone marrow. Systemic mastocytosis is usually diagnosed by a positive bone marrow biopsy. However, sometimes people are diagnosed by biopsies of other organs. Skin biopsy is NOT enough to diagnose systemic mastocytosis.
• For systemic mastocytosis, there are three key things they are looking for in the biopsy.
• They are looking for at least one cluster of at least fifteen mast cells.
• They are looking for some of the mast cells to be shaped like spindles, sort of smushed at the ends and round in the middle. You see this shape a lot when cells are trying to stick together in a cluster.
• They are looking for special proteins that are only found when a patient has systemic mastocytosis or monoclonal mast cell activation syndrome. They are called CD25 and CD2. These are like flags that the mast cells fly to tell us they are broken. One of them, CD25, actually helps mast cells cluster together.
• In biopsies, they usually also look for the protein CD117. This is a normal flag for mast cells to fly and just allows us to know that we are looking at mast cells.

For more detailed reading, please visit these posts:

The Provider Primer Series: Management of mast cell mediator symptoms and release

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 6

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

12. What do these blood and urine tests look for?

• There are a lot of tests ordered for mast cell disease. How they are interpreted can depend upon a lot of factors. Some of the tests are unreliable, a fact that will be addressed in detail later in this series. (And has been addressed in detail elsewhere on this blog). Please keep in mind when reading this post that I am being VERY general and assumed the test was performed correctly on a correctly stored sample.
• The most common test ordered for mast cell disease is serum tryptase. Tryptase is a molecule that mast cells release. While it has lots of functions in the body, and is especially important in healing wounds and tissue growth, the amount present in your body at a given moment should be low.
• Tryptase is special because mast cells release it in two ways. Firstly, they make and release a little bit steadily. This is not related to activation. Mast cells just normally release a little tryptase as they go about their work. So the idea is that if you have more mast cells than you should, and each of those mast cells releases a little tryptase all the time, that you will have a higher than normal serum tryptase.
• Patients with a clonal mast cell disease, in which they have too many broken mast cells, usually have elevated baseline tryptase. This means tryptase that is elevated at least two times when you are NOT having a big reaction or anaphylaxis.
• Mast cells also store lots of tryptase in their pockets. When the mast cell is activated and it empties out its pockets, lots of tryptase comes out at once. This is why tryptase can be higher after a reaction or anaphylaxis, because mast cells release a bunch at once.
• Patients with mast cell activation syndrome or cutaneous mastocytosis do not always have elevated tryptase even with a big reaction or anaphylaxis.
• Mast cells have huge amounts of histamine stored in their pockets inside their cells. Histamine has lots of functions inside the body and is required for normal body functions. In particular, it is important to our nervous system. Smaller amounts are released as a normal function of the body.
• A lot of histamine is released when mast cells are activated. The idea is that if your mast cells are more activated than they should be that your histamine level will be higher. However, the test recommended for us to consider the histamine level in mast cell patients is not for histamine. It is for n-methylhistamine. This is a molecule that is formed when the body breaks down histamine, which happens very quickly (within minutes of release). n-methylhistamine is more stable, which is why we look at it.
• The test for n-methylhistamine is most reliable when performed in a 24 hour urine sample. This is because the level in urine can fluctuate throughout the day.
• Mast cells make a lot of prostaglandin D2 (abbreviated PGD2). PGD2 is very important for cell communicating. It can carry a message from one cell to another, allowing cells to work together. Unlike histamine and tryptase, mast cells do not keep PGD2 stored in their pockets. They make it only when they need it and then release it.
• PGD2 is released in large amounts when mast cells are activated. However, because it is not stored in the pockets, it is not always elevated right away when you have a big activation event or anaphylaxis. Prostaglandin D2 is broken down quickly. While we do test directly for PGD2 for mast cell disease, we also test for 9a,11-PGF2, a molecule formed when PGD2 breaks down.
• The tests for PGD2 and 9a,11b-PGF2 are most reliable when performed in 24 hour urine samples. This is because the levels in urine can fluctuate throughout the day.
• Heparin is a blood thinning molecule that is stored in pockets inside mast cells. Mast cells are the only cells that release significant amounts of histamine. When the mast cell is activated and it releases histamine, the histamine comes out stuck to heparin. Heparin is broken down very quickly so it is hard to measure accurately.
• The test to assess heparin level actually looks for a molecule called anti-factor Xa that can interact with heparin. This test is performed in serum.
• Chromogranin A is released by mast cells. It is also released by a lot of other cells. The level of this molecule can be affected by many things, including common medications. It is sometimes tested for and considered a sign of mast cell disease if elevated when all other possible reasons can be excluded.
• Chromogranin A levels are most reliable in serum.

 

For more detailed reading, please visit these posts:

The Provider Primer Series: Management of mast cell mediator symptoms and release

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 5

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

10. How is mast cell disease diagnosed?
• There are several tests you need to definitively determine if you have mast cell disease and what kind you have.
• The most well known test for mast cell disease is serum tryptase. This is a blood test. This is the test doctors are most likely to have heard of. Doctors may think that you can’t have mast cell disease if tryptase is normal. This is not true.
• If a patient has a tryptase over 20 ng/mL, the next step is usually a bone marrow biopsy. A tryptase over 20 ng/mL increases the likelihood that a patient has systemic mastocytosis. SM is most commonly confirmed by a bone marrow biopsy.
• You need a special stain in order to see mast cells in any biopsy. Stains that show mast cells include Giemsa Wright stain and toluidine blue. Your doctor should specify these stains.
• Several tests must be run on the bone marrow biopsy to look for clonal mast cell disease. Remember that in clonal diseases, the body makes too many broken cells.
• The shape of the mast cells in the biopsy is very important. If the mast cells are not shaped right, this can be a sign of mast cell disease.
• The number of mast cells grouped together in the body is also important. If 15 or more mast cells are all stuck together, this is called a cluster. When mast cells are clustered together like this, they can punch holes in the tissue and damage it a lot. This prevents the tissue from working right.
• Immunohistochemistry (IHC) is a way to find specific proteins that allow us to know what cells we are looking at in the biopsy. Often, these proteins are on the outside of the cells. Think of these are flags that a cell can wave. IHC can look for the specific flags a cell is waving so that we know for sure which cell is which. For mast cell disease, they want to look for CD117, CD25, and CD2. The CD117 flag is flown normally by all mast cells. CD25 and CD2 are special flags flown by mast cells if you have clonal mast cell disease.
• PCR is a way to look for genetic mutations. They need to look for a mutation in the mast cells in the bone marrow. The mutation is found at a specific place in the CKIT gene. This mutation is found in 80-90% of patients with systemic mastocytosis. It may also be found if patients have monoclonal mast cell activation syndrome.
• If a patient does not have a tryptase over 20 ng/mL, a bone marrow biopsy is often not ordered. There are other tests that can indicate mast cell disease.
• Urine collected over 24 hours can be tested for specific chemicals. In the case of mast cell disease, they are looking for chemicals that can be high if you have mast cell disease. These chemicals have very long, complicated names. I will explain in a later post exactly what they are and what they do. The most common ones are called n-methylhistamine, prostaglandin D2, 9a,11b-prostaglandin F2, and leukotriene E4. Anti-heparin Xa and chromogranin A are sometimes tested. They are much less reliable as indicators of mast cell disease than the others mentioned here.
• If a patient is suspected to have cutaneous mastocytosis, a skin biopsy is needed to confirm. As with bone marrow biopsies, your doctor should specify that they need to use toluidine blue or Giemsa Wright stain to be sure they see the mast cells.
• The skin biopsy should also receive the other tests I described above for bone marrow biopsy: the counting of mast cells and looking at the shape; looking for CD117, CD2, and CD25; and looking for the same mutation with PCR.
11. What kind of doctor diagnoses mast cell disease? Can any doctor order these tests?
• Doctors from all different specialties may diagnose and manage mast cell disease. It depends upon the individual provider and where you are located. It could be a dermatologist, allergist, hematologist, pulmonologist, gastroenterologist, or another specialist.
• The serum tryptase is the easier to order and the most well known test. Many labs can run this test.
• The 24 hour urine tests are specialized. Some of them are run in only a few places and samples are usually shipped there. Most often, these samples are run at the Mayo Clinic. Many outpatient labs have no way to run those tests. You will need to speak with your doctor about how to get these tests. It is often easiest if they are run by a hospital lab but again, this depends upon the hospital.
• The PCR genetic test for this specific gene is run in more places than the urine tests but is still not very common. Again, it is often easiest if they are run by a hospital lab.
• A bone marrow biopsy is usually ordered by a hematologist or by another specialist that works commonly with hematologists. They are usually performed by hematology providers. Some testing can usually be performed in house (the counting of the cells and looking at the shape) while others may need to be sent out (the IHC testing).
• A skin biopsy is usually ordered by a dermatologist. Some testing can usually be performed in house (the counting of the cells and looking at the shape) while others may need to be sent out (the IHC testing).
For more detailed reading, please visit these posts:

The Provider Primer Series: Management of mast cell mediator symptoms and release

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 4

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

8. Why are symptoms not the same for everyone?

  • Bodies are very complex. This sounds silly to say because of course bodies are complex, but the amount of work a body does on a second to second basis is staggering. All of your organs are working all the time. The way they are working depends on hormones, how recently you ate, if you are stressed out, what kind of environment you live in, if you have been or are pregnant, how old you are, if you are sexually active, where you are in your menstrual cycle, what medications you are on, and what things happened to you up to this point in your life. Not everyone’s body does the same things.
  • Mast cells are involved in regulating many processes at the same time that all of these things are happening. It is releasing chemicals to make these things happen and is receiving messages from other cells.
  • Mast cells are key cells in inflammation. Inflammation is when cells from the immune system tell the body that it is under attack. Some of those cells are white blood cels that were already present. Inflammation causes many white blood cells, including mast cells to go to the site of the inflammation. For example, if you break your arm, the cells near the broken bone will send messages that it needs help from immune cells. Those immune cells will then physically move to the place they were called to. Mast cells may move to the site of inflammation in this way.
  • When an area has been inflamed, sometimes white blood cells stick around even when the area is healed or healing. Mast cells can also do this. If an area is inflamed, you may end up with many mast cells in that spot where there had originally only been a few.
  • When an area has been inflamed, the immune cells nearby can be extra easy to activate for a while. They are “primed”. Primed cells are much more likely to start a new inflammatory episode, even for something tiny, because they are easier to activate. They remember that they previously had to call for help so their instinct is to do it again. In this way, old injuries may “act up” easily. This can keep nearby mast cells primed or even activated long term.
  • Mast cells have pockets called granules that store chemicals inside them. These chemicals are called mediators. They perform many of the mast cell’s normal functions.
  • Mast cells have different jobs in different places in the bodies. The mediators stored inside those pockets are not the same in all mast cells. They are full of the mediators that they need most to do specific jobs in that area. Mast cells can also make new mediators to do specific jobs. The mediators they make are also tailored to their specific jobs.
  • Some mediators are very specific and some are not. Think of this like sending an email. You can send an email to a particular person. This is specific. You can also send an email to an address used by many people, like an email account for several people who work in customer service. Any of them might see it and respond but you don’t know which one. This is nonspecific. Mast cell mediators might talk to just one type of cell or to several kinds of cells, either nearby or in other parts of the body. Which mediators are released can also depend on previous inflammation. Which mediators are released, where they are released, and how much is released also vary from person to person.

9. Why do symptoms change over time?

  • Symptoms can change over time for all of the reasons they are not the same from person to person.
  • It is also possible that symptoms can change due to progression of disease from one diagnostic category to another. For example, patients may suddenly notice their abdomen is swollen and hard. That could be because their liver is swollen and not working properly.
  • You CANNOT assume that the disease is progressing because symptoms change. Symptom change is NOT a marker for progression.
  • Mast cell disease is not inherently progressive. Many people never have a change in diagnosis.

For more detailed reading, please visit these posts:

The Provider Primer Series: Management of mast cell mediator symptoms and release

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 3

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

6. What symptoms does mast cell disease cause?

  • Mast cell disease can cause just about any symptom. Seriously.
  • Mast cell disease can cause symptoms in every system of the body. This is because mast cells are found in tissues throughout the body. They are intimately involved in lots of normal functions of the human body. When mast cells are not working correctly, lots of normal functions are not carried out correctly. When this happens, it causes symptoms. In short, mast cells can cause symptoms anywhere in the body because they were there already to help your body work right.
  • Skin symptoms can include flushing, rashes, hives (urticaria), itching, blistering, and swelling under the skin (angioedema).
  • GI symptoms include nausea, vomiting, diarrhea, constipation, problems with the GI not moving correctly in general (GI dysmotility), swelling of the GI tract, chest and abdominal pain, belching, bloating, discolored stool, excessive salivation, dry mouth, and trouble swallowing.
  • Cardiovascular symptoms include high or low blood pressure, fast or slow heart rate, irregular heartbeat, and poor circulation.
  • Neuropsychiatric symptoms include brain fog, difficulty concentrating, difficulty sleeping at night, excessive tiredness during the day, grogginess, anxiety, depression, tremors, numbness, weakness, burning and tingling (pins and needles), hearing loss, and auditory processing (difficulty understanding what was said to you).
  • Genitourinary symptoms include bladder pain, painful urination, painful intercourse/sexual activities, painful or irregular menstrual cycle (periods), and excessive or inadequate urination (too much or too little urine produced).
  • Respiratory symptoms include cough, excessive phlegm, wheezing, runny nose, sinus congestion, sneezing, and swelling of the airway.
  • General symptoms include fatigue, lack of stamina, difficulty exercising, itchy or watery eyes, and bruising easily.
  • There are some additional symptoms that I have observed in a large number of people that are not classically considered mast cell symptoms, but I now firmly believe them to be. One is fever. I think discoloration of the skin may be mast cell related for some people. Another is dystonia, involuntary muscle contraction, which can mimic appearance of a seizure. There are also different seizure-type episodes that may occur due to the nervous system being overactive. I am reluctant to call them pseudoseizures because that term specifically means they are caused as a result of mental illness. I have no evidence that these seizure-type episodes in mast cell patients occur due to mental illness. I personally refer to them as “mast cell derived seizures.” (For people who are wondering, I have been heavily researching this phenomenon and have some theories about why this happens. It’s not fleshed out enough yet to post but it’s on my think list.)
  • Having mast cell disease can make you more likely to have other conditions that cause symptoms.
  • I’m sure there are other symptoms I have forgotten to mention.

7. Why are skin and GI symptoms so common?

  • The skin has a lot of mast cells relative to other tissues. Your skin also comes into contact with lots of things in the environment. Think about the things your skin touches on a daily basis! It makes sense that it would get the exposure so skin symptoms can be common. Additionally, some of the chemicals mast cells release can cause fluid to become trapped in the skin. For these reasons, symptoms affecting the skin are pretty common.
  • The GI tract also has a lot of mast cells relative to other tissues. Your GI tract also comes in contact with lots of things in the environment. Let’s think about this for a minute. Your GI tract is essentially one long tube through your body. You put things from the environment in your GI tract at the top and they come back out the bottom of the tract. In a way, your GI tract is kind of like the outside of the inside of your body.
  • This is the analogy I learned in anatomy and physiology class to visualizing the GI tract as the outside of the inside of the body. Think of the body as a donut. (A low histamine, fully allergy friendly, requires no GI motility, wonderful donut.) Now think of the GI tract as the donut hole. You can put your finger through the hole in the middle of the donut. Only that center part of the donut will touch your finger. This is kind of like putting food throughout the GI tract. That food only touches a very small part of the body as it passes through.
  • Since what we put into our mouths (or other GI openings) is from the outside, your body has many mast cells in the GI tract to protect the body. Some of the chemicals mast cells release can cause fluid to become trapped in the layers of GI tissue. Some of the medications we take for mast cell disease can affect the GI tract. Some of them change how much acid we make in our stomachs. Some of them slow down the GI tract. A few of them speed it up or make the GI tract more fragile. For these reasons, symptoms affecting the GI tract are very common.

For more detailed reading, please visit these posts:

The Provider Primer Series: Management of mast cell mediator symptoms and release

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 2

I have answered the 107 questions I have been asked most in the last four years. No jargon. No terminology. Just answers.

3. What causes mast cell disease?

  • The cause of mast cell disease is not yet definitively known.
  • As mentioned yesterday, when the body makes too many copies of a broken cell, those cells are called ‘clonal’ cells. In clonal forms of mast cell disease, the bone marrow makes too many mast cells. Those mast cells also don’t work correctly. Examples of clonal mast cell diseases are systemic mastocytosis and cutaneous mastocytosis.
  • Patients with systemic mastocytosis often have a specific genetic mutation called the CKIT D816V mutation. About 80-90% of systemic mastocytosis patients have this mutation. This mutation is in mast cells and it tells the mast cells to stay alive WAY longer than they should. And mast cells already live for months or years, a very long time for cells to live in the body. So patients with this mutation can end up with way too many broken mast cells.
  • Despite the fact that we know that many patients have this mutation, we do not say that this mutation CAUSES the disease. The reason for this is that sometimes, mast cell patients don’t have the mutation when they get sick but they develop it later. Sometimes, mast cell patients have the mutation and then lose it later. So we are still looking for something that causes the disease.
  • Patients with non-clonal mast cell disease do not have a single major mutation like the CKIT D816V mutation. This makes it harder to diagnose. Researchers have found that many times, patients with MCAS DO have mutations similar to the ones systemic mastocytosis patients do. But the MCAS patients often have different mutations from each other. That’s why it’s not helpful yet for diagnosis.
  • Despite the fact that the mutations described here are not considered to be heritable, there is more and more evidence that mast cell disease can happen to many people in the same family. See the next question for more details.

4. Is mast cell disease heritable?

  • Mast cell disease often affects multiple members of the same family. Importantly, patients often have a different type of mast cell disease than their relatives. This implies that mast cell disease is more of a spectrum rather than several different diseases.
  • A survey found that 74% of mast cell patients interviewed reported at least one first degree relative that had mast cell disease. This same study found that 46% of those patients had mast cell disease that affected more than just their skin. This is called systemic disease.
  • The CKIT D816V mutation is the mutation most strongly associated with clonal mast cell disease. The CKIT D816V mutation is NOT heritable.
  • There are very rare instances of other heritable mutations in families that have mast cell disease. The significance of this is not clear.

5. Can mast cell disease be cured?

  • Generally speaking, there is no cure for mast cell disease.
  • Children who present with cutaneous mastocytosis sometimes grow out of their disease. Their lesions disappear. Their mast cell symptoms affecting the rest of the body may disappear. We do not know why this happens. It has been heavily researched with long term follow up of children with childhood mastocytosis (at least one paper followed them for 20 years).
  • Children with true systemic mastocytosis do not grow out of their disease.
  • There is not yet data on children with MCAS. Anecdotally, they do not seem to grow out of their disease like kids with cutaneous mastocytosis can. Importantly, this is just what it looks like to me. Again, there is no data.
  • People with adult onset mast cell disease have lifelong disease.
  • There is one notable exception to this scenario. There are reports of curing mast cell disease following hematopoietic stem cell transplant/bone marrow transplant.
  • Transplantation is EXTREMELY dangerous. The transplant is MUCH, MUCH more dangerous than mast cell disease. Many people do not survive the protocol necessary to prepare for transplant. Many die from complications, or from a disease they acquired after their transplant.
  • Rarely, people may have malignant forms of mast cell disease, aggressive systemic mastocytosis (ASM) or mast cell leukemia (MCL). A few patients with these diseases have tried transplants after everything else failed. While some did see improvement after transplant, no one has survived more than a few years.
  • Conversely, sometimes people with mast cell disease have these transplants for other reasons, like having another blood cancer or bone marrow disease that requires transplant. In this group of people, some see drastic improvement of their mast cell disease. Some see a full remission of mast cell disease. Some do not get any improvement. These findings are pretty recent so it’s hard to be more specific.

For more detailed reading, please visit these posts:

The Provider Primer Series: Introduction to Mast Cells

The Provider Primer Series: Mast cell activation syndrome (MCAS)

The Provider Primer Series: Cutaneous Mastocytosis/ Mastocytosis in the Skin

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (ISM, SSM, ASM)

The Provider Primer Series: Diagnosis and natural history of systemic mastocytosis (SM-AHD, MCL, MCS)

Mast cell disease in families

Heritable mutations in mastocytosis