In systemic mastocytosis (SM), mast cells proliferate abnormally and accumulate in the body’s organs and connective tissue, including the skin, bone marrow, gastrointestinal tract, spleen, liver and lymph nodes.
Over time, the buildup of mast cells causes inflammation and damage to the organs. In the lymph nodes, this excessive mast cell activity causes swelling. As part of the body’s immune system, the lymph nodes are bean-shaped glands found in the neck, armpits, chest, groin and abdomen, and when they become swollen, it is called lymphadenopathy.
What is SM?
Systemic mastocytosis (SM) is a rare hematological disease characterized by mast cells that are overactive and accumulate in different parts of the body such as the bone marrow, liver, spleen, gastrointestinal tract and lymph nodes.
Symptoms of SM
When mast cells are activated in an allergic reaction, they trigger a range of symptoms. The main symptoms of SM are skin irritation, hives, flushing, itching, abdominal pain, diarrhea, nausea, vomiting, bone and joint pain, low blood pressure, fatigue, depression, brain fog, mood changes, enlarged liver, spleen or lymph nodes and in most serious cases, anaphylaxis.
Learn more about SM symptoms
These symptoms can vary from person to person, with differing degrees of severity and effect on daily life. Symptom management involves recognizing and avoiding triggers such as certain foods and medication, sudden changes in temperature, physical exertion, emotional stress, insect stings and skin friction. Antihistamines and mast cell stabilizers will help alleviate symptoms.
The role of the lymph nodes in the body
There are hundreds of lymph nodes in the body. As part of the body’s immune system, they contain lymphocytes or white blood cells that filter foreign substances and fluid from the lymphatic system and fight infection from bacteria or viruses by attacking and destroying damaged cells and germs. When there is an infection in the body, lymph nodes become inflamed and swollen.
Lymph nodes and SM
In the case of SM, when the lymph nodes become enlarged and remain persistently enlarged, it can indicate disease progression or possible complications.
However, as lymph nodes become enlarged when fighting infection and injury, as well as more serious conditions such as cancer, it is not always clear why they are swollen. In some cases, swollen lymph nodes in SM have been mistaken for lymphoma. Other symptoms common to both SM and lymphoma include itchy skin, fatigue, enlarged spleen and unexplained weight loss.
SM is diagnosed via a number of tests, including through blood or urine, bone marrow, skin and gastrointestinal biopsies, as well as imaging tests such as X-ray, ultrasound, bone scan and CT scan. A lymph node biopsy may also be performed to measure the mast cell infiltration.
