#mast cell activation disorder

[kirby-the-gorb]

we are about an hour into rare disease day in my timezone! (it's always the last day of february, whether that's the 28th or the 29th.) the true prevalence of mast cell disorders is unknown, as they are often misdiagnosed or ignored. and mast cell activation syndrome, the most prevalent kind of mast cell disorder, only had diagnostic criteria laid out for the first time in 2010. so whether or not it's truly rare is really up in the air!

(personally I suspect it is just aggressively underdiagnosed but I'm not a research scientist or diagnostician right now. and even if it is rare, it's gonna be a lot less so than it was 5 years ago as certain respiratory infections are known to trigger it into visibility. that's what happened to me when I got mono at the end of 2015, further compounded when I got covid in 2022.)

all chronically ill people face a lot of hurdles when it comes to seeking diagnosis, accommodation, and treatment (all of which can be severely complicated by any intersecting marginalities), but rare diseases present a special challenge.

for example, I have an immune disorder. my immune system does not like being alive, my mast cells are way too jumpy and throw a tantrum over every little thing. you'd think an immunologist would be the one to treat me, right?

I've had 6 immunology referrals rejected in the past 9 months alone. multiple major immunology clinics in my major city tied to a major research university outright refuse to see patients with "mcas" written anywhere in their chart.

after 8 years of being debilitatingly ill, and suspecting it was immune mediated for 6, and getting it confirmed beyond a shadow of a doubt by the bone marrow biopsy last month, I will have my second ever appointment with an immunologist. another 2 1/2 months from now. the first immunologist lied to me about the reliability of the one available blood test, when I first came up with the hypothesis by myself 6 years ago, and forced me to abandon my (correct!!! now proven!!!) hypothesis for 3 entire years while we wandered around lost and got nowhere other than even more thorough process of elimination.

okay, well if my immune system is attacking me, maybe it's technically autoimmune? that's the rheumatologists instead of the immunologists, what do they have to say? dick all my dude, I don't have rheumatoid arthritis so they just shrug at me and go "idk, fibro? I don't know why you're here" and send me home with nothing. (I literally had a rheumatologist say to me, verbatim, "I don't know why you're here." buddy it's your job to read the chart and decide if I get seen or not, you tell me. at least he had a snazzy outfit.)

being chronically ill can be a terrible struggle no matter what, but a disease that is perceived as rare, accurate or not, adds a whole new layer of bullshit. (and of course there are much much rarer diseases out there, with even more hoops and dead ends and struggles and all-new layers of bullshit that even I don't have to deal with!)

anyway I'm having a shit time and using this awareness day as an excuse to productively bitch about it 👍

[wheelie-sick]

What is Idiopathic Mast Cell Activation Syndrome?

Idiopathic Mast cell activation syndrome (MCAS) is one of several mast cell disorders. MCAS occurs when there are a normal number of mast cells in a person's body but they over-release mast cell mediators causing random allergic reactions in multiple systems of the body. MCAS is incredibly common being present in an estimated 17% of the population.

Symptoms

MCAS symptoms are incredibly varied and always occur in multiple systems of the body. Anaphylaxis is common.

[ID: A graphic labeled "Some common symptoms of Mast Cell Disease" A graphic of a person standing in the center with multiple organs visible is shown. Around the person are lines pointing to specific areas of the body labeled with the body system and symptoms. Clockwise these read "Neurological headache, brain fog, cognitive dysfunction, anxiety, depression Cutaneous (Skin) flushing of the face/neck/chest, hives, skin rashes, itching with or without rash Cardiovascular light-heartedness, syncope (fainting), rapid heart rate, chest pain, low blood pressure, high blood pressure at the start of a reaction, blood pressure instability Gynecological uterine cramps, bleeding Urinary bladder irritability, frequent voiding Systemic and/or organ specific Anaphylaxis angioedema (swelling) Skeletal bone/muscle pain, osteopenia, osteoporosis Gastrointestinal diarrhea, nausea, vomiting, abdominal pain, bloating, gastroesophageal reflux disease (GERD) Ear/Nose/Throat/Respiratory nasal itching and congestion, throat itching and swelling, wheezing, shortness of breath and more" In the bottom left corner "Symptoms can be sudden and unpredictable in onset learn more at tmsforacure.org"]

MCAS symptoms are specifically not allergies. the reactions may look like allergies but the two are not the same and MCAS is not a condition meaning "many allergies" While MCAS can have some consistent triggers one of the defining features of the disease is that reactions are random and happen unpredictably.

Anaphylactic shock is not a requirement for diagnosis.

Diagnosis

MCAS is diagnosed by an immunologist. It is in part a diagnosis of exclusion and requires ruling out both allergies and systemic mastocytosis as well as other conditions such as certain types of tumors.

Diagnostic criteria for MCAS is debated. Some immunologists follow the symptom-based diagnosis approach in which case the diagnostic criteria are:

Recurring and severe anaphylactic-like episodes that involve more than one organ system

and

Positive response to mast cell stabilizing or mediator medications anaphylaxis-type symptoms

Others follow diagnostic criteria based on laboratory findings. In this case the diagnostic criteria are:

Episodic symptoms consistent with mast cell mediator release affecting two or more organ systems evidenced as follows:

Skin: urticaria, angioedema, flushing

Gastrointestinal: nausea, vomiting, diarrhea, abdominal cramping

Cardiovascular: hypotensive syncope or near syncope, tachycardia

Respiratory: wheezing

Naso-ocular: conjunctival injection, pruritus, nasal stuffiness

and

A decrease in the frequency or severity; or resolution of symptoms with anti-mediator therapy: H1 and H2 histamine receptor antagonists, anti-leukotriene medications (cysLT receptor blockers or 5-LO inhibitor), or mast cell stabilizers (cromolyn sodium)

and

Evidence of an elevation in a validated urinary or serum marker of mast cell activation: Documentation of elevation of the marker above the patient’s baseline during a symptomatic period on at least two occasions; or if baseline tryptase levels are persistently >15ng, documentation of elevation of the tryptase above baseline on one occasion. Total serum tryptase is recommended as the markers of choice; less specific (also from basophils) 24 hour urine histamine metabolites, or 11-beta-prostaglandin F2.

and

Primary (clonal) and secondary disorders of mast cell activation ruled out.

These are not all proposed diagnostic criteria as the subject is heavily debated. Generally, a laboratory-confirmed MCAS diagnosis is considered more legitimate.

Treatment

MCAS is a very treatable condition. Generally treatment follows a path from antihistamines -> mast cell mediators -> biologics.

Epipens are given to MCAS patients with a history of anaphylaxis.

Antihistamines are divided into 2 categories: H1 antagonists and H2 antagonists. These categories are determined based on the histamine receptor each one targets.

H1 antagonists mostly deal with systemic and cutaneous symptoms. H1 antagonists are also further divided into first and second generation antihistamines. first generation antihistamines include diphenhydramine (Benadryl) and Hydroxyzine. These tend to cause drowsiness. With second generation H1 antagonists cause fewer side effects and include drugs like loratadine (Claritin) and cetirizine (Zyrtec)

H2 antagonists primarily affect the gastrointestinal tract and include medications like famotidine (pepcid)

Typically when treating MCAS a person will be put on both a second generation H1 antagonist and an H2 antagonist.

When antihistamines do not treat symptoms well enough the next step is a mast cell mediator. The most common mast cell mediator is cromolyn sodium which is available by prescription only. (this is technically available OTC but it is at 1/50th the dose used for MCAS) Mast cell mediators work by preventing the degranulation of mast cells in the first place.

When both antihistamines and mast cell mediators are insufficient someone with MCAS might be prescribed a biologic such as Xolair to treat their remaining symptoms.

Sources:

American Academy of Allergy, Asthma, and Immunology

Mast Cell Hope

Mast Cell Activation Syndrome: Proposed Diagnostic Criteria

[ehlers-danloscircus]

Does this mean we can finally get rid of soy in literally everything

[thescrappyraccoon]

Post 5/7

Meme dump for my fellow spoonies! Sending 🥄🥄🥄 and 🩵🩵🩵

[mandiweirdmore]

Dude I’m so done with healthy people “everyone’s life is uneventful compared to Mandi”. I need some chronically I’ll friends. 😭😭😭

[chronically-j]

hiii ok i dont think i have MCAS but im curious if this is a symptom of that (or something similar?) or if its normal, because idk if i should bring it up to my dr or not!

so, i think its call skin writing? like, with barely any pressure, if i run my nail across my skin, it turns red and sometimes swells slightly, with very mild itchiness.

is that something my dr needs to know about? im genuinely asking because i have a ridiculously hard time knowing whats important or not and i usually assume its all nothing but im trying to be better about that

(using a few extra tags for reach)

[twisted-rat-king]

why the fuck is my immunologist allowed to just... not write a prescription for a refill of my mast cell stabilizers without warning. I have MCAS. I am allergic to literally everything. OTC antihistamines hardly put a dent in my allergies, even if i quadruple the doses (which is generally the highest you can safely go).

i could literally die without these meds.

[ablednt]

I know the same things don't work for everyone but does anyone have a H1 and H2 antihistamine combo I can get over the counter to suggest? Currently not on either (I've tried a lot of h1 antihistamines on their own but this was long before I knew about MCAS) and the daily agonies are a solid -200 out of 10

[vulpeculaaaaa]

Hey y'all! I just got diagnosed with MCAS and have been told to follow a low histamine diet.

Do any of you have any tips? Perhaps food brands you can eat?

[dollyboned]

i hate having mcas.

that's it. i said it.

it's so tiring. i can't run, or go for long walks, or just sweat a little. i don't have enough strength for staying up for more than 20min, i can't eat some spices that i totally adore, and my spoons are usually so low. sometimes i simply don't want to get out of bed because im so tired but i have to do so anyway, and usually it happens when i know i'll have p.e. classes. i don't think i completed the two classes since the start of the academic year (february) without stopping and sitting and breathing heavily and feeling so itchy because i can't exercise too much or my histamine levels go high as the sky and being covered by sweat is like wearing a full costume made out of histamine, that im *specially* allergic to.

i see people running and jumping and simply walking under the sun and i feel like im missing something because im so young yet so limited. i should be able to be just fine if the climate changes, or if there's something spicy in the food, or if i need to walk a little, or if i just need to walk by a slightly inclined street, but im totally not able to be "just fine" and move on. my dad gets worried everytime we come back from school and i almost faint because of the exercise, and even though i try to explain how i feel, i know he still thinks that maybe it'd be better if i just exercised a little more to build up strength — and he's not the devil because he can't understand it as we only discovered my histamine intolerance this year because of some medical exams i made when i was 4 and my pediatrist never properly explained. i was 4 and now im 15 — it's basically 11 years being exposed to something im deeply allergic to and never understanding why i'd never get better from dermatitis and why i was so weak.

i feel fragile. my parents know i hate being seen as fragile and breakable and weak yet i can't take any longer. im constantly itching, my mind is always kinda numb, im always tired, my periods always hurt, i have constant migraines, my mood swings are worsening and on top of everything comes the game changer: im also neurodivergent. there's always going to exist someone that have the energy to do everything, and that's not me. socially im basically incapable of approaching people i find cool, the amount of work i've got to do to simply exist like a normal person is unbearable and yet i have to be responsible, good, well mannered, pretty, smart, cool, cute, role model, the best. i never learned to fail. i was always the smartest, the joyful, the responsible, the "i wish your grades were like her's" — i feel so bad to everyone who felt so little next to me because i never wanted anyone to live under a shadow of a version of me that i can't even recognize or remember anymore.

the little me would've looked at me with fear on her eyes and asked if we are failing for being so weak and so tired we can't even really care about learning something. are we really failing? i'm just so tired. i could do better if i wasn't constantly battling in order to only navigate my days without this haunting exhaustion taking me over, or if my head didn't hurt that bad, or if my emotional regulation was a little bit more effective, or if the sounds weren't so loud and the light so bright and people so confusing. i could do better if i wasn't restraining myself from eating something i love because i don't want an allergic reaction, or if i could just stim around, or if i could run around under the sun and laugh about it after. maybe if i had some adjustments my life would get so better. i don't want to run with anyone to feel like im part of something; i just want to feel okay with every aspect of myself, and maybe feeling okay is sitting down everytime i feel tired and taking medicine everytime there's an allergic reaction going on, not reducing myself to grades and stop wearing a damn mask in order to be liked.

i hate having mcas, i hate how my scoliosis correction surgery is never taken seriously when it comes to "it's painfully tiring to carry titanium inside me everyday", and i hate how misunderstood i am. i get it now: im not lazy, im simply chronically exposing myself to a lot of things and now my body is totally overloaded. i've been deeply sick for the past weeks and it's caused mainly by the overwhelming sensation of getting up, getting tired, being misunderstood and having everything to do when i don't have that energy to expend. i want to sleep, watch things about my favorite anime, write a little about it, allow myself to really rest for the first time in my life, eat healthy things that aren't like an allergy bomb inside my organism and i really, really, really want to get to live again, being understood and taken seriously, not ever being called lazy or nothing else. i just want to control what happens to myself and stop feeling on the verge of tears everytime i have to do something that requires movements and focus.

little me would be so sad we lost control over our own body to an allergy that could've been minimized before it ruined our life.

[slightlybritish]

it’s kind of fucked up that trauma makes your immune system sometimes stop working

like what the fuck man

[wheelie-sick]

right now everything touching me burns and I'm so tired I'm doing everything I can I'm gonna restart antihistamines in the meantime and see if that helps but it fucking sucks that my MCAS meds just aren't working well enough anymore

[thescrappyraccoon]

Post 4/7

Meme dump for my fellow spoonies! Sending 🥄🥄🥄 and 🩵🩵🩵

[mandiweirdmore]

If you saw me having a panic attack in the BBQ sauce isle no you didn’t 😎. Side note why does everything have black pepper and high fructose corn syrup. Side side note why am I allergic to the weirdest things 😭😭😭

[beanie-beebo]

Autoimmune vent

I don't usually vent on here but I know there are a lot of people struggling and fighting with this type of stuff so I guess I'm just looking for a space that's easy access

I'm down to basically one food that doesn't cause anaphylaxis. I'm exhausted. Kinda scared too ngl. I can't go outside, I can't spend time with my birds, I can't do chores, I barely have energy half of the time to do things I enjoy.

I just need it to get better. I know it will at some point but.. I'm tired. I want a good rest.

[sillyspoonie-shitposting]

Got really bad sunburn on my legs cos I can’t wear sun cream due to allergies and was stuck in the sun. Fortunately had UV sleeves on my arms, might need to get some for my legs too.

Aqueous cream to the rescue, hoping it heals alright and stops hurting soon.

Update: it got worse, turns out my new meds cause bad sunburn and photo sensitivity. Only on a low dose so far so it’s probably going to get worse. :(