Learn The BasicsThe symptoms of systemic mastocytosis (SM) develop as a result of the release of chemicals from mast cells. Due to this, they are similar to symptoms of an allergic reaction, but without an obvious trigger.
The signs and symptoms of SM differ based on which part of the body is affected. The severity of these symptoms may vary from one individual to the other and range from mild to life-threatening.
Symptoms may develop at any age but usually occur in patients who are ages 50 and over.
General signs and symptoms of SM
The general signs and symptoms of SM may include extreme fatigue, muscle pain, low blood pressure and lightheadedness.
Non-specific symptoms may include pain, nausea, headache, difficulty with memory and concentration and malaise.
Most patients with SM also develop a skin condition known as urticaria pigmentosa which consists of raised itchy patches of brownish skin.
Almost half of patients with SM also experience severe allergic reactions known as anaphylaxis, which is caused by massive chemical release from the mast cells, also known as degranulation that can be life-threatening.
Signs and symptoms based on mast cell location
In patients with SM, mast cells can accumulate in the skin, liver, spleen, bone marrow and digestive tract. In rarer cases, they can also build up in the brain, heart or lungs and cause symptoms accordingly.
When mast cells accumulate in the skin, patients may experience flushing, itching or hives.
If mast cells accumulate in the digestive tract, patients may experience acid reflux, abdominal pain, bloating, diarrhea, nausea or vomiting. In more severe cases, patients may have peptic ulcer disease and gastrointestinal bleeding.
The accumulation of mast cells in the bone marrow can lead to anemia, which affects around half of patients. It can also lead to bleeding disorders and bone pain, as well as osteopenia and osteoporosis.
When they accumulate in the liver or spleen, mast cells can cause the organs to enlarge, especially in the advanced stages of the disease, known as hepatomegaly and splenomegaly, respectively. Splenomegaly occurs in around 50% of SM patients.
In rare cases, mast cells can accumulate in the brain. This may lead to symptoms such as anxiety, depression, mood swings, problems concentrating or increased fatigue. These symptoms are sometimes referred to as mixed organic brain syndrome.
The accumulation of mast cells in the lungs may cause shortness of breath and wheezing.
Patients may experience one or more of the above symptoms simultaneously.
Symptoms associated with an accompanying blood disorder
Patients with SM who have another blood disorder may also show symptoms of that disease.
These may include fatigue, pain in the left upper quadrant due to an enlarged spleen, bruising or bleeding and weight loss.
Factors that may trigger the development of SM symptoms
The signs and symptoms of SM may develop as a result of certain triggers.
These may include insect venom, certain drugs such as opioids, antibiotics, pain killers or non-steroidal anti-inflammatory drugs (NSAIDs), certain foods, pollen, sudden changes in temperature, direct sunlight, skin irritants and physical and emotional stress.
