Skip to content

pediatric mastocytosis

The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 34

41. Can my mast cell disease go away? Will it ever not be a problem?

There are several common questions that basically all distill down to these sentiments. I’m going to answer them all here.

I have previously answered the question “Can mast cell disease be cured?” in this series but I think this question is a little different. When people ask if mast cell disease can go away, they mean can it become no longer a problem even if it’s not cured. That’s what I’m answering here.

This answer is very complicated so I’m just going to give my thoughts let’s about all sides of this situation.

Yes, it is possible for mast cell disease to be controlled enough to no longer be a problem in your life. But there are a lot of caveats.

The most common presentation of mast cell disease in cutaneous mastocytosis (mastocytosis in the skin) in children. In about 2/3 of cases, children “grow out of” their mast cell disease. Specifically, this means that they lose their skin lesions and have no obvious mast cell symptoms by their late teenage/early adult years. We don’t know why this happens.

However, there are instances where a person who grew out of their childhood CM have mast cell issues later in life. We have a greater understanding of mast cell diseases now and we know that you can have a whole host of mast cell issues without having skin lesions. So it’s not as clean cut as was previously thought.

For more serious forms of systemic mastocytosis, it is possible that with treatment, the disease can be “knocked down” to a less serious category. For example, a patient with aggressive systemic mastocytosis who does chemo may find that it helped enough that their diagnosis is now smoldering systemic mastocytosis. Or a patient with SSM has a big drop in the number of mast cells zooming around after taking interferon and now they have indolent systemic mastocytosis. While symptom severity doesn’t necessarily change when a patient has a less serious diagnosis, that does sometimes happen.

With the exception of childhood cutaneous mastocytosis, all other forms of mastocytosis are considered lifelong ventures. This includes all forms of adult onset cutaneous mastocytosis and all forms of systemic mastocytosis for children or adults. However, there are instances of patients with SM where bone marrow transplant seems to cure their disease. We need to continue to follow mast cell patients who have had bone marrow transplants to see how many of them have recurrence of mast cell disease.

Mast cell activation syndrome is often secondary to some other condition. Basically, one disease irritates your body so much that your mast cells flip out in response to the disease. The disease that caused the mast cell problem is called the primary condition. In these instances, mast cell activation syndrome is sometimes considered to be dependent upon the primary condition. This means that some doctors and researchers feel that if you control the primary condition, the mast cell activation syndrome will go away.

This sentiment seems straightforward but is actually pretty complex. Let’s pull it apart. Let’s say your primary condition is lupus. You are a patient with lupus. The lupus irritates your body so much that your mast cells just go bananas. Now you are a patient with lupus who has secondary MCAS. The lupus in this instance caused the MCAS. But what does that mean? Does that mean that without the lupus, you would never have had MCAS? Or does it mean that you would eventually have had MCAS secondary to something else? This is the topic of a lot of debate. (I personally am of the belief that MCAS is genetic and therefore you were always going to develop it at some point.) So it’s not clear yet whether a primary condition really “causes” MCAS or just wakes it up.

However, what is not disputed at all is that any type of inflammation can trigger mast cell activation and symptoms. So if you are a lupus patient, and your lupus is going crazy, that’s going to really bug your mast cells. If you are able to control your lupus, it will decrease the inflammation, which will calm your mast cells. But calming your mast cells isn’t really the same thing as your mast cell disease going away. Not having symptoms is not the same thing as being cured.

Another thing to consider is that even if the lupus is what triggered your MCAS, once your MCAS is triggered, it’s going to be triggered by everything. You can very easy get locked into a cycle where the lupus irritates your MCAS, which irritates your lupus, and around you go. So in a situation like this, where the mast cell activation is really out of control, it sometimes doesn’t matter what the primary condition is, and controlling the primary condition might not help.

Many patients with mast cell disease have their symptoms controlled enough to live pretty normal lives. Some mast cell patients don’t have really symptoms at all, even without medications. In a small group of MCAS patients, after a year of treatment with antihistamines and mast cell stabilizers, about 1/3 had complete resolution of symptoms and another 1/3 had one only symptom that was a problem. 

However, it’s important to remember that this is not having debilitating symptoms is not the same as not having mast cell disease. These patients are still predisposed towards mast cell activation and should take mast cell precautions for things like surgery or dental work. Many patients stay on antihistamines and/or a mast cell stabilizer even with good symptom control because it affords some protection from bad reactions and anaphylaxis. Patients should only stop regular medication with the supervision and direction of a provider who knows them. Additionally, trialing things like foods you reacted to, or starting an exercise program, require provider input.

You should also keep in mind that mast cell disease can be very erratic. It doesn’t always follow a trend so symptoms steadily improving does not guarantee that symptoms will stay well controlled. So while mast cell disease can be managed enough to not be a problem, there is always the possibility that it will show up again. Once you have a mast cell diagnosis, you are always going to be looking over your shoulder.


The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 33

40. What is mastocytosis of childhood? Is mast cell disease different for children than adults?

Cutaneous mastocytosis in children is the most common form of mastocytosis. True systemic mastocytosis, in which the WHO criteria are met, is very rare in children.

In many ways, mastocytosis in children has huge differences from mastocytosis in adults. The exact reason for this is unclear. Because of how different the disease path can be for children, doctors and researchers sometimes refer it as mastocytosis of childhood. However, there is not officially a distinct diagnostic category.

Unlike in adults, mastocytosis in children is sometimes both benign and transient. Many kids have symptoms that either stay the same or improve as they get older. Many kids grow out of their mastocytosis. About 2/3 of children with cutaneous mastocytosis have no evidence of disease (no skin lesions or symptoms) by their late teen years or early adulthood. Many other children have improvement of symptoms and signs without completing growing out of their condition.

Children with mastocytosis often have some unusual things in their bone marrow biopsies. They often have clusters of mast cells and eosinophils with other cells in their bone marrow. However, the mast cells in those clusters are often normal mast cells and do not have the same markers we see in adults. Many of these children have more mast cells in their bone marrow biopsies than adults with mastocytosis. However, unless the biopsy shows true SM, it does not affect prognosis for the children. Children may have unusual things in their bone marrow biopsies but still go on to grow out of it.

The exception is if the child has true SM. Children with true SM do not grow out of their disease.

Children with mastocytosis often have symptoms that affect multiple organ systems, not just their skin. Abdominal pain and bone pain are often reported. Systemic symptoms do not tell us whether or not the child has SM or whether or not they will grow out of their disease.

An NIH study that included 105 children with mastocytosis found that children with normal baseline tryptase tests had negative bone marrow biopsies. It also found that a tryptase level elevated after anaphylaxis or a bad reaction did not signify that the child had SM. However, they did find that all children with SM had internal organ swelling. Most children with SM were positive for the CKIT D816V mutation.

There are no studies yet on the differences between adults and children with MCAS. There are enough anecdotal findings to suggest that children with MCAS do not grow out of their disease the way children with CM sometimes do.

For more detailed reading, please visit these posts:

Childhood mastocytosis: Update

Progression of mast cell diseases (Part 5)

Childhood mastocytosis: Update

One of the more confusing aspects of mastocytosis is that childhood mastocytosis often bears little resemblance to adult-onset mastocytosis and has a very different natural history.  Cutaneous mastocytosis in children is the most common presentation of mastocytosis. True systemic mastocytosis (meeting WHO SM criteria) is quite rare in pediatric cases.

A recent paper describes the features of 105 children assessed at the NIH.  They found that the children in this group either had a stable disease state or improved, with 30-65% getting better over time.  None of the children received cytoreductive therapy.

They found that in this group, children with normal baseline tryptase levels had negative bone marrow biopsies.  A single elevated tryptase level was not determined to correlate well with to a positive bone marrow, rather an elevated baseline tryptase was a good indicator of SM. No children without systemic mastocytosis had organ swelling.

Likewise, all children with systemic mastocytosis had both elevated baseline tryptase and swelling of internal organs.  Bone marrow mast cell burden correlated well with tryptase value. The average tryptase for children with SM in this study was 111.5 ng/ml. Tryptase decreased over time in some SM children.  The researchers recommended evaluation of serum tryptase every 6-12 months.

All children with organ swelling were found to have SM. Children with swelling of both liver and spleen were found to be positive for the D816V CKIT mutation.  Swelling of both of these organs indicates that disease is more likely to persist into adulthood.  Of total 19 children with SM, 16 were positive for the CKIT D816V mutation.

In children with UP, the average tryptase value was 5.9 ng/ml. Twelve children with UP had tryptase values of 11-20, and six had values over 20. Children with UP most often saw significant decreases in tryptase levels over time.   Most UP children with skin and minor GI issues had normal tryptase values.

Children with DCM had much higher average tryptase values, with an average of 67. 85% of DCM children had tryptase over 20 ng/ml when diagnosed.  None of them had swelling of organs.

Of 105 children assessed in this study, 3 had elevated monocytes; 22 had elevated white blood cells; and 12 had elevated platelets.  All of these values returned to normal by the end of the study.  Seven had increased clotting time (PTT). Of those with longer clotting times, four had lupus antibodies and one had Factor VII deficiency. All seven PTT values returned to normal.  Two children with DCM and one with UP had iron deficiency anemia.  One patient had significant elevation of alkaline phosphatase, which resolved.  Researchers noted an inverse correlation between serum tryptase and IgE levels in this group.


Carter et al. Assessment of clinical findings, tryptase levels, and bone marrow histopathology in the management of pediatric mastocytosis. J Allergy Clin Immunol 2015.