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MastAttack 107

The MastAttack 107: The Layperson’s Guide to Understand Mast Cell Diseases, Part 27

35. Why are there different sets of criteria for mast cell activation syndrome? What are the differences between them?

To answer this fully, we need to first discuss the history behind some terms.

Mast cell activation syndrome was first used to describe episodes of mast cell mediator release symptoms in a paper published in 2007 (Akin 2007). Specifically, the term was used to detail the experience of patients who had symptoms we commonly associated with mast cell activation, like flushing, hives, and low blood pressure.

However, the patients in this study were all found to have some features of systemic mastocytosis. While they had some of the criteria for an SM diagnosis, they didn’t meet all the criteria. These patients sort of looked like SM and quacked like SM but would not cleanly meet the diagnostic criteria. So the author of that paper made a separate diagnostic category for them. He called it monoclonal mast cell activation syndrome.

The use of the word “monoclonal” is VERY important here. Monoclonal is a medical term that is associated with the body making too many cells at once so that the cells that are made don’t work correctly. Systemic mastocytosis is a condition in which the body makes too many cells at once that don’t work right. It is a monoclonal disorder. So the author of that paper in 2007 is linking monoclonal mast cell activation syndrome to systemic mastocytosis. He thought of it as sort of a “pre-SM” or “early SM”.

Shortly after that 2007 paper was released, another school of thought was proposed by different groups about the nature of mast cell activation syndrome. These groups also linked the term mast cell activation syndrome to symptoms of mast cell activation, like flushing, hives, and all the rest. However, they did NOT link mast cell activation syndrome to monoclonality. This means that these researchers felt that mast cell activation syndrome could be present without a condition where you make too many sloppy cells like systemic mastocytosis. So patients with no evidence of systemic mastocytosis could still have mast cell activation syndrome according to these groups. The two major groups that believed MCAS was distinct from SM were led by Afrin/Molderings and Castells.

Let’s recap:

In 2007, Akin described mast cell activation syndrome as something that happened only in patients that had some evidence of systemic mastocytosis but not enough to be diagnosed with systemic mastocytosis. In order for this group to diagnose you with mast cell activation syndrome, you had to have evidence of systemic mastocytosis. It was an add on diagnosis to SM, sort of like SM with really bad symptoms.

In the years that followed, two groups, led by Afrin/Molderings and Castells, described mast cell activation syndrome as something that was distinct from systemic mastocytosis and could be found in anyone, even if they had no evidence of systemic mastocytosis at all.

Okay. So these two groups agreed that MCAS could happen to anyone. But they differ greatly in how they think MCAS can be diagnosed. For these groups, MCAS is NOT an add on diagnosis to systemic mastocytosis. It is a standalone diagnosis and entity.

So if the term MCAS was already being used, why didn’t the other groups just call their diagnosis something different? There isn’t a good answer to this but it is super common. Things are much more fluidly changing in the time between coining a term and having the diagnosis accepted by a large organization like the CDC so that your insurance can bill for treatment for that diagnosis. It would be great if everyone just used different names for their variants but this just doesn’t always happen.

Castells feels that in order to be diagnosed with MCAS, you have to show mast cell mediator symptoms, response to medications to treat mast cell activation, and evidence of mast cell activation. You also have to rule out every other possible cause of mast cell activation. Keep in mind that your mast cells are normally activated for lots of reasons so this can really difficult to do.

Additionally, this school considers mast cell activation to be evidenced only by elevation of serum tryptase, 24 hour urinary n-methylhistamine or 24 hour urinary prostaglandin D2 or 9a,11b-prostaglandin F2. So if none of these mediators are high, the patient doesn’t meet the criteria for diagnosis.

Afrin’s criteria are harder to explain because he believes that you should provisionally be diagnosed with mast cell activation disease, which can be a few different things, and then it should be narrowed down to mast cell activation syndrome or another mast cell condition.

The key difference between Afrin’s criteria and Castells’ are that he accepts elevated levels of several other mast cell chemicals to prove mast cell activation. Afrin counts toward diagnosis elevation of serum tryptase, 24 hour urinary n-methylhistamine, serum or 24 hour urinary prostaglandin D2 or 9a,11b-prostaglandin F2, 24 hour urinary leukotriene E4, heparin in blood, and chromogranin A in blood. All of these are released by mast cells. But some of them are released by other cells too so it’s not as easy to say for sure that mast cells cause the elevations. Additionally, some of these mediators are REALLY difficult to measure accurately, like heparin. So some people feel that these tests are less reliable to indicate mast cell activation alone.

Let’s talk about puppies for a second because when things get tough, just find a puppy and things will be cool from there on out.

Let’s present these three schools of thought on MCAS as puppies.

Let’s say that Akin is saying that all dogs with 10 spots on them have SM. He’s saying that dogs with some spots, but less than 10, have MCAS. He is also saying that dogs with NO spots CANNOT have MCAS.

Castells is saying that it doesn’t matter how many spots the dog has but it has to have either blue or green eyes to have MCAS. She doesn’t think the MCAS is related to spots but that it is related to specific eye color.

Afrin is saying that it doesn’t matter how many spots the dog has, or what color eyes. He will accept eyes of many other colors if the dog has a lot of symptoms that look like mast cell activation or respond to medications to treat mast cell activation.

I have simplified this as much as possible so it’s easier to understand. For that reason, I have omitted a lot of things. I am in no way saying that what I described here represents everyone’s experience. I am not saying that at all.

If you want my opinion on what MCAS is, and I’m inclined to think you do because you’re on my website reading my thoughts about mast cell disease, I feel that the evidence points strongly towards a space that blends both Afrin’s and Castells’ points. I feel that we should use more mast cell mediators than just serum tryptase, 24 hour urinary n-methylhistamine, serum or 24 hour urinary prostaglandin D2 or 9a,11b-prostaglandin F2. But I personally find the reliability of tests for heparin level to be very problematic and elevations of chromogranin A can be from so many things. I am not AT ALL saying that people diagnosed with these elevated markers do not have MCAS. I professionally develop diagnostics and these tests are just not great.

I also don’t think there’s enough evidence yet to say that mast cell disease can be proven with a biopsy demonstrating a certain number of mast cells per hpf (high powered field, this is a measurement we use for counting things we see under a microscope). I think it is very suggestive of inflammation and mast cell activity. But there are MANY instances in which normal, healthy, asymptomatic patients have a bunch of mast cells/hpf in their biopsies when they are used in studies.

So I’m solidly in the MCAS is its own entity group but don’t fall evenly into one group or the other regarding diagnosis.

Regarding treatment, I land more squarely with Afrin. I believe that if you have tried all of the conventional treatments and continue to have life threatening episodes, you should be able to try more drastic treatments provided you are well supervised by a knowledgeable provider. This is my personal opinion and in no way reflects the views of my employer. I think that if you are constantly anaphylaxing, or have no safe foods, or have dystonic seizures, or can’t stand up, and you have gone through a long list of “reasonable treatments” that you have a right to try to preserve your life and the quality thereof with any means available.

So, yea. MCAS is a can of worms. But we owe it to MCAS patients to have these awkward discussions even though it’s, well, awkward. Patients are falling through the cracks and we owe it to them to identify what criteria would let us catch them so they can get diagnosed and treated sooner.

I’ve tried hard to explain this objectively but if I haven’t done great, let me know in the comments.

For more detailed reading, please visit these posts:
The Provider Primer Series: Mast cell activation syndrome (MCAS)
MCAS: Differing criteria among experts

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 26

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

34. What are the differences between the forms of systemic mastocytosis?

Indolent systemic mastocytosis

  • A form of SM in which the amount of mast cells produced in the bone marrow is excessive but not inherently dangerous to organ function.
  • Mast cells produced in the bone marrow are damaged.
  • These mast cells are released into the blood. While there are more mast cells than usual, there are not enough to overwhelm the blood.
  • There are fewer mast cells than in mast cell leukemia. There are often fewer mast cells than aggressive systemic mastocytosis or smoldering systemic mastocytosis.
  • The mast cells leave the blood and may enter organs inappropriately. Some patients do not have signs of too many mast cells being in an organ other than bone marrow.
  • The presence of mast cells in organ tissue can cause symptoms and medical signs but is not inherently dangerous to organ function.
  • It is not unusual for ISM patients to have typical mast cell symptoms and complications like anaphylaxis.
  • The lifespan for ISM is normal.
  • In indolent systemic mastocytosis, patients die from progressing to a more aggressive form of SM, such as MCL, ASM or SM-AHD.
  • Fatal anaphylaxis is always a risk with mast cell disease.

Smoldering systemic mastocytosis

  • A form of SM in which the amount of mast cells produced in the bone marrow is increasing to the point at which it might cause organ damage.
  • Mast cells produced in the bone marrow are damaged.
  • These mast cells are released into the blood. There are fewer mast cells than in mast cell leukemia. There are often fewer mast cells than aggressive systemic mastocytosis.
  • Mast cells leave the blood and enter organs in larger numbers than is normal. The presence of mast cells in these organs can cause symptoms and medical signs, like swelling of the liver.
  • Organ dysfunction can sometimes be corrected with surgery or certain medications.
  • It is not unusual for SSM patients to have typical mast cell symptoms and complications like anaphylaxis.
  • The lifespan for SSM is widely variable. One well known paper published survival of around ten years. However, many of the patients in this study were over 60 and age may have affected the average survival found in this group.
  • Patients with smoldering systemic mastocytosis are monitored to look for signs of significant organ dysfunction.
  • People with this diagnosis are considered to be possibly transitioning to a more serious form of systemic mastocytosis.
  • Smoldering systemic mastocytosis is the diagnosis that occurs between aggressive systemic mastocytosis and indolent systemic mastocytosis. It is thought of as the stage crossed when a patient with indolent systemic mastocytosis progresses to having aggressive systemic mastocytosis or mast cell leukemia.
  • In smoldering systemic mastocytosis, patients die from progressing to a more aggressive form of SM, such as MCL, ASM or SM-AHD.
  • Fatal anaphylaxis is always a risk with mast cell disease.

Aggressive systemic mastocytosis

  • A dangerous form of SM in which your bone marrow makes way too many damaged mast cells.
  • These mast cells are released into the blood. There are fewer mast cells than in the blood than in mast cell leukemia.
  • The mast cells leave the blood and go into various organs.
  • The presence and activation of the mast cells in the organs can affect organ function.
  • Over time, the presence and activation of mast cells in the organs can cause organ failure. This can sometimes be corrected with surgery or certain medications.
  • Typical mast cell mediator symptoms and complications like anaphylaxis are less common than in less serious types of SM.
  • The lifespan for ASM is much shorter than normal but is dependent upon response to treatment and which organs are involved. Older papers reference an average of 41 month survival but this has changed with more recent treatment options.
  • Generally, people with ASM live longer than those with MCL.
  • In aggressive systemic mastocytosis, patients die from the organ damage that has accrued over time by the presence and activation of mast cells in places they don’t belong.
  • Fatal anaphylaxis is always a risk with mast cell disease.

Mast cell leukemia

  • A very dangerous form of SM in which your bone marrow makes massive amounts of damaged mast cells.
  • These mast cells are released into the blood in overwhelming numbers.
  • The mast cells leave the blood and end up in various organs.
  • Specifically because of how many mast cells are present, mast cells invading the organs break up the organ tissue and cause severe organ damage.
  • The organ damage leads to organ failure, which leads to death.
  • Typical mast cell mediator symptoms and complications like anaphylaxis are less common than in less serious types of SM.
  • The lifespan for MCL is much shorter than normal.
  • Lifespan for MCL is usually quoted as being in the range of 6-18 months. However, there are more recent reports of some patients living 4+ years.
  • In mast cell leukemia, patients die from the organ damage caused by large amounts of mast cells entering and breaking up organ tissue.
  • Fatal anaphylaxis is always a risk with mast cell disease.
  • Of note, there is a newly described chronic form of mast cell leukemia. In this form, patients have stable mast cell disease despite having an overwhelming amount of mast cells in their bodies. The reason for this is unclear and long term survival is not yet known.

Systemic mastocytosis with associated hematologic disease

  • A form of SM in which the patient also has a separate blood disorder that produces too many cells of a different kind.
  • A patient with systemic mastocytosis with associated hematologic disease has too many mast cells and too many blood cells of a different kind. 
  • Previously called SM-AHNMD, systemic mastocytosis with associated clonal hematologic non mast cell lineage disease.
  • The two blood disorders, SM and the other disorder, are treated separately the same way they would be if the patient only had one or the other.
  • The lifespan for SM-AHD is wildly variable as it depends both on which type of SM the patient has as well as the type and severity of the other blood disorder.
  • An important thing to remember is if a patient has SM and another blood disorder that produces too many cells, they are classified as SM-AHD regardless of the type of SM they have. For example, if a patient who has ISM (normal lifespan) also has chronic myelogenous leukemia, they have SM-AHD. However, if the patient has ASM (shortened lifespan) and chronicle myelogenous leukemia, they still have SM-AHD even though the prognosis changes considerably.
  • In SM-AHD, patients die from having an aggressive form of SM, such as MCL or ASM, or as a result of their other blood disorder.
  • Fatal anaphylaxis is always a risk with mast cell disease.

For more detailed reading, please visit these posts:
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 25

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

 

33. What is the difference between primary and secondary disorders? How do you know if your disorder is primary or secondary?
• This is a case where we badly need better vocabulary for describing a phenomenon than these two words. The reason for this is because primary and secondary have an inherent numerical association – primary means first, secondary means second. We think that it means primary disorders happen first and secondary happen after. This isn’t always the case.
• A primary disorder does not mean the first disorder to be found. It also does not necessarily mean the disorder that causes other disorders. In this context, primary means only that the disorder arose irrespective of any other health issues, that it was always going to happen anyway.
• So let’s say you have a primary disorder, systemic mastocytosis. Now let’s say that you have another health issue. Whether you had cancer, a bad sunburn, or a broken toe, systemic mastocytosis was always going to happen to you. Or if you lived a charmed life and never had another health issue at all, even a runny nose. Systemic mastocytosis was always going to happen to you.
• We need to make a very, very important distinction here. Somewhere inside your cells was a seed that would later grow into systemic mastocytosis. However, sometimes that seed grows much faster because something else happens to you. People sometimes say “I got SM after I got pregnant”, or “I got SM after a bad car accident”. This isn’t really accurate. You were going to get SM at some point anyway. These are things that really activate mast cells so sometimes events like that can trigger mast cells so that you see the disease then for the first time.
• Clonal disorders are disorders where your body makes too many cells that don’t work correctly. Clonal disorders are almost always considered primary diseases. Clonal mast cell diseases are monoclonal mast cell activation syndrome, mastocytoma, mast cell sarcoma, and all forms of systemic mastocytosis and cutaneous mastocytosis. In all of these conditions, the body makes too many mast cells that do not function correctly.
• Now remember – primary does not mean first. It also does not meet only. You can have multiple primary diseases. You can have systemic mastocytosis and a genetic immunodeficiency. Both of those are primary. If you never had SM, you would still have the genetic immunodeficiency. If you never had the genetic immunodeficiency, you would still have SM. You can have multiple primary disorders.
Secondary disorders are disorders that do depend upon another health condition. Many disorders are secondary.
• For example, steroid induced diabetes is a classic example of a secondary disorder. If you take high dose steroids for too long, you develop diabetes as a result. But if you can get off the steroids, the diabetes resolves. You only had the diabetes because of the steroids. The diabetes was not always going to happen to you. It happened because of the steroids.
• When mast cell patients ask about primary and secondary diseases, they are almost always asking about mast cell activation syndrome. Mast cell activation syndrome is overwhelmingly considered to be a secondary disease. Many patients with MCAS have other diseases and MCAS is thought to be a reaction of the body to the stress and damage of the other diseases. Autoimmune diseases, connective tissue diseases, and even bad IgE allergies are commonly cited as the primary diseases that MCAS is secondary to.
• In a conversation with a world known authority on mast cell diseases, I was told that about 95% of MCAS is thought to be secondary. I also think that MCAS is almost always secondary, though I haven’t seen data to really feel solidly convinced of that.
The terms “primary MCAS” and “monoclonal mast cell activation syndrome” are usually used interchangeably. This is because monoclonal MCAS is clonal (too many broken cells) and clonal diseases are primary diseases.
• However, I am not personally convinced that there is no other primary form of MCAS. This is the same caveat as the previous point – there’s just not enough data. I do think that most MCAS patients have secondary disease. But those are just thoughts without evidence.
In idiopathic disorders, you don’t know why they happen. The same expert told me that idiopathic MCAS occurred in about 5% of cases. In these instances, the patients did not have any other diagnoses that were thought to cause secondary MCAS (and sometimes no other diagnoses at all).
• Let’s review.
• Primary disorders were going to happen to you at some point no matter what.
• Secondary disorders happen when your body reacts to something else happening in your body.
• Idiopathic disorders have no obvious cause.

This is an extremely confusing topic. Please ask questions in the comments if you have them.

For more detailed reading, please visit these posts:
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 Disease, Part 23

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

  1. Is mast cell activation the same as mast cell activation syndrome?
  • No.
  • This is the single most important clarification I make as an educator. It is crucial to understand that they aren’t the same thing, especially if you research mast cell activation syndrome online.
  • Mast cell activation is a normal and healthy process. Mast cell activation mostly means that they are ready to release chemicals in response to signals from inside the mast cell or from other cells. It is one of the major ways mast cells carry out their normal functions, like fighting infections, healing the body post trauma, and regulating the menstrual cycle.
  • Many things activate mast cells to tell mast cells to act in their normal functions. Bacteria, viruses, fungi, cancer cells, diarrhea, pain, surgery, physical or emotional stress, and many other things all activate mast cells normally. It is not surprising that these things activate mast cells because they should activate them.
  • Sometimes mast cells overreact to signals to activate, like in allergies and anaphylaxis.
  • The reason mast cell activation is a problem in mast cell disease is because mast cells respond way too strongly to activation signals. They release too many chemicals too often.
  • The other reason mast cell activation is also a problem in mast cell disease is because they become too easily activated.
  • Think of mast cells like houses. Like any house, they have doors. In healthy people, you need a lot of people knocking on the doors and windows at the same time to get the mast cell to open the doors and release chemicals. In mast cell patients, one person can knock a few times and all the doors open and release chemicals at once.

For more information, please visit this post:

The Provider Primer Series: Introduction to Mast Cells

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Disease, Part 22

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

  1. Does mast cell disease cause cognitive issues?
  • Yes.
  • The most common cognitive issue reported by mastocytosis patients is “brain fog”, a sort of difficulty in thinking and reacting normally.
  • Inability to focus, pay attention, find words, and keep things in short term memory are frequently reported by mast cell patients. Attentive deficit disorders are sometimes seen.
  • Aside from the effects of mast cell disease on your body, they also affect the lives of patients dramatically. 42% of mastocytosis patients in one study reported a high stress level. I would be willing to bet that across the entire population of mast cell patients, the number of people that feel a lot of stress is a lot higher than 42%. Many patients feel hopeless, guilty, or like a burden. While this is distinct from depression, a neurologic disorder, these feelings can make it hard for patients to focus or pay attention.
  • Mast cell disease can lower serotonin. Even where this is not the case, mast cells can greatly impact the way serotonin works in the body. Serotonin in a chemical that nerves and other cells use to talk to each other. It is also important in cognition. While this isn’t totally understood yet, it appears that increasing serotonin levels can improve memory and decrease impairment. It can also improve ability to learn things. Not enough serotonin was associated with memory and learning difficulties.
  • When mast cells are activated, your body thinks there is an emergency or an infection. It can activate a stress response. One of the things your body does during this response is release cortisol. Cortisol can further activate mast cells. It is also released by mast cells. Over time, more cortisol than normal can really fatigue the body. Long term stress response is associated with a lot of cognitive issues, including brain fog.
  • Mast cell disease is very disruptive to your sleep cycle. Personally, this is one of the hardest parts of the disease for me. Your body naturally starts releasing more histamine around 10pm, every night, for everyone. Mast cell patients often have worsened symptoms starting around then and continuing overnight.
  • Another mast cell mediator, prostaglandin D2 (PGD2), is the strongest known inducer of sleep in the body. Mast cell patients may have this in excess, making them even more tired.
  • Despite the common idea that histamine makes you drowsy, it actually keeps you awake. Many mast cell patients have insomnia because of the histamine release overnight. This translates to being exhausted during the day when histamine levels drop. Lack of sleep is a well documented cause of cognitive dysfunction.
  • Many mast cell patients have POTS or another form of dysautonomia. These conditions can prevent getting enough blood and oxygen to the brain.

For more information, please visit these posts:

Neuropsychiatric features of mast cell disease: Part 1 of 2

Neuropsychiatric features of mast cell disease: Part 2 of 2

MCAS: Neurologic and psychiatric symptoms

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 21

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

30. Why does my skin get red and itchy?
• Flushing is one of the hallmark signs of mast cell disease. It is sometimes the symptom that drives providers to look at mast cell disease as a potential diagnosis.
• Mast cells make and release many chemicals. These chemicals are commonly called mediators because they mediate many reactions in the body that affect the body in many different ways.
• Some mast cell mediators make blood vessels relax. The vessels get a little wider. When the vessels get bigger, the ones under the skin get closer to the skin. Because those vessels show red from the blood in them, the blood is closer to the skin so the skin looks red.
• Flushing is often asymmetrical. There isn’t a hard and fast reason for why this happens but is likely caused by local mast cell mediator release. Essentially, if the mast cells on the right side of your face get irritated, the right side is more likely to flush than the left side.
Flushing is mostly mediated by prostaglandin D2. Aspirin is often prescribed for mast cell patients that tolerate it because aspirin blocks cells from making prostaglandins. This is because aspirin interferes with the molecule that manufactures them. Many other substances can also interfere with this, including other NSAIDs. Another class of drug, 5-lipoxygenase inhibitors, can also stop production of prostaglandins in a different way.
• To a lesser extent, histamine contributes flushing and antihistamines sometimes help.
What exactly causes itching is still not entirely clear. There are special little places in your body called itch receptors. When they notice something itchy, it’s their job to raise the alarm. We think that mast cells carry the message from those places to the nervous system that then spread the itch signal. It’s like carrying the flame of one candle from the itch receptor to the nervous system, which sets the forest on fire.
• Hydroxyzine and other antihistamines are often used for itching. Corticosteroids like prednisone, either oral or topical, may help. Also, medications that interfere with prostaglandin production, like an NSAID or a 5-lipoxygenase inhibitor, sometimes help.

For more detailed reading, please visit these posts:
The Provider Primer Series: Management of mast cell mediator symptoms and release
Prostaglandins and leukotrienes
Mast cell mediators: Prostaglandin D2 (PGD2)

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 20

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

29. Why do I swell up when I have a reaction? Where does the fluid come from and where does it go?
• Your body feeds its cells by keeping blood circulating. The blood passes by cells. The cells pull nutrients, oxygen, and other things they want out of the blood. In return, the cells release their wastes into the bloodstream to carry them away to a place where they can be broken down.
• Mast cells make and release many chemicals. These chemicals are commonly called mediators because they mediate many reactions in the body that affect the body in many different ways.
• Mast cell mediators do many things. They can make blood vessels get looser or tighter to help control heart rate and blood pressure. Their ability to make blood vessels relax is the important point when considering swelling. When mast cells release certain mediators, the vessels relax and get a little wider.
• Vessels are made of a complicated network of cells and fibers. It’s like an afghan blanket: some parts of mostly solid and in other places, there are holes you can put your fingers through. When the vessels relax, those holes get larger so it’s easier for things to fall through the holes. In this case, what falls through the hole is fluid from the blood.
• Keep in mind that blood is a mixture of many things. For right now, let’s divide it into cells and everything else. Everything else is a liquid with some stuff dissolved in it.
• When the blood vessels relax, that liquid from the blood trickles out of the blood vessel and goes into the tissue. In some cases, if the blood vessels relax enough, cells actually fall out of the bloodstream and end up in tissue, too.
• The problem is that once you fall out of the bloodstream, you can’t just turn around and go right back in. That’s why swelling takes longer to subside than other symptoms, even with appropriate treatment.
• Everyone is familiar with the bloodstream. Less familiar is the lymphatic circulatory system. Lymphatic circulation is how your body moves things that fall out of the blood back to the bloodstream. This process is slower than processes that can release other symptoms and can sometimes take days.
• When you swell up, fluid falls out of your bloodstream and gets stuck in your tissues. The cells nearby will absorb some of the fluid and take up molecules they can use. However, if there is a lot of extra fluid there, the cells nearby cannot take up all of the fluid. Gradually, your lymphatic system sucks up that fluid and brings it back toward the heart so it can get back into the bloodstream.
• When you get hives (urticaria), it happens because fluid falls out of the bloodstream in a layer of tissue in the skin called the upper dermis.
• When you get angioedema, it happens because fluid falls out of the bloodstream in lower portions of tissue in the skin called the dermis, subcutaneous tissue, mucosa, and submucosa.
• The fact that the process for hives and angioedema is so similar and really distinguished only by which tissue layer they affect is the reason urticaria and angioedema so commonly occur together and are discussed together.

For more detailed reading, please visit the following posts:
Chronic urticaria and angioedema: Part 1
Chronic urticaria and angioedema: Part 2
Chronic urticaria and angioedema: Part 3
Chronic urticaria and angioedema: Part 4
Chronic urticaria and angioedema: Part 5
The Provider Primer Series: Management of mast cell mediator symptoms and release

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 19

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

28. Why are so many mast cell patients anemic?
• Anemia occurs when a person has too few red blood cells or not enough hemoglobin. Red blood cells are essentially envelopes that serve specifically to hold hemoglobin. Hemoglobin is a molecule made with iron that picks up oxygen. When you have either too few red blood cells or they don’t have enough hemoglobin, not enough oxygen gets to all the parts of the body that need it.
Patients with chronic illness of many kinds often have anemia. This is called anemia of chronic inflammation or anemia of inflammatory response.
• This type of anemia occurs because of the overactivity of a hormone called hepcidin. This hormone tells cells in the GI tract to hold onto any iron they find. This means they do not pass the iron along to the blood so it can make hemoglobin. Since the body isn’t making enough hemoglobin, the body doesn’t get enough oxygen.
• Mast cell patients often have anemia of chronic inflammation so they may be anemic regardless of how much iron they have in their diet. However, increased supplementation sometimes helps.
• There are several forms of iron that can be taken by mouth. IV iron is also an option. Some people have luck cooking in cast iron pans or using the “Lucky Iron Fish” to get even more iron into their diet in hopes that they can take up a little bit more.
Having enough iron available also decreases mast cell activation. Mast cells make smaller amounts of inflammatory molecules when the body has sufficient iron.
• Mast cell patients may also selectively malabsorb iron in their GI tracts. This means that even if they are absorbing enough of other nutrients, they may not absorb enough iron properly due to inflammation. This sometimes improves with antihistamines.
• Mast cell patients usually take histamine H2 blockers. This decreases the strength of stomach acid which can affect absorption of nutrients like iron. Taking PPIs can do the same thing.
• Malabsorption of other nutrients, like copper, can contribute to anemia.
• Insufficient amounts of B12 or folate can cause also contribute to anemia.

For more detailed reading, please visit these posts:
Anemia of chronic inflammation
MCAS: Anemia and deficiencies
Effect of anemia on mast cells

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 18

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

27. Can mast cell patients travel? Can they fly?
• This is very individual and dependent upon your personal health situation, your ability to manage bad reactions on your own, where you live and where you want to travel. I have been fortunate enough to be able to travel widely through exhaustive preparation.
• You should always talk to your care team when you are thinking about travel. You must have a detailed understanding about how to recognize when you are headed for trouble, what you should do if you get into trouble, and when you should pursue emergency care.
Always carry rescue medications, your emergency protocol on provider letterhead, and a sheet listing your diagnoses, daily meds, rescue meds, and any special precautions. List over the counter medications as well.
• Make sure that all of your medications are legal in the country you are traveling to. Importantly, diphenhydramine (Benadryl) is illegal in some countries.
Get a fit to fly letter detailing what medications you need to bring onboard with you on letterhead from your doctor.
Call the airline directly to describe your needs. If you need to use medical equipment during the flight, tell them when you call and have the model number/ serial number ready.
• Also notify the airline if you need them to refrigerate medication for you.
• If standing is a trigger, or you have difficulty lifting luggage or carrying your bags with you, ask for a wheelchair to meet you at check-in and take you through the gate. It is my experience that when bringing a lot of medications through experience, it is easier to do this when you are in a wheelchair being escorted by airport personnel.
Identify safe foods at your destination. Many countries do not allow you to bring food in from another country. However, you can often bring solid food through the security to have on the plane.
• I premedicate heavily and many other mast cell patients who regularly fly also find that helpful. Speak with your providers about what protocol works best for you.
• Flying is unbelievably dehydrating. Hydrate well in the days before flying, the day of the flight, and while flying.
• Keep in mind that if the flight crew is uncomfortable with you flying, they can refuse to let you onboard. Emphasize that it is safe for you to to fly and that you have a fit to fly letter. If you are not able to manage a bad reaction alone, please do not fly alone.

For more detailed reading, please visit these posts:

How to travel with mast cell disease