Mastocytosis
Mastocytosis is a rare condition caused by an abnormal build-up of mast cells in the body.
Overview
Mastocytosis is a rare condition caused by an abnormal build-up of mast cells in the body. Mast cells are part of the immune system and help with allergic and inflammatory responses. When too many mast cells accumulate, they can release excessive amounts of chemicals such as histamine, leading to a range of symptoms. Mastocytosis can affect only the skin (cutaneous mastocytosis) or involve internal organs such as the bone marrow, liver or digestive system (systemic mastocytosis).
Causes and Genetics
Mastocytosis is usually caused by a change (mutation) in the KIT gene, which affects mast cell growth and survival. Most cases are not inherited and occur sporadically. In children, mastocytosis often affects only the skin and may improve over time. In adults, systemic forms are more common.
Symptoms and Features
Symptoms vary depending on the number of mast cells and the organs involved.
Characteristic Symptoms and Features
- Skin rash (often brownish spots or patches)
- Itching
- Flushing
- Swelling of affected areas
Other Associated Symptoms and Features
- Abdominal pain
- Diarrhoea
- Nausea
- Headaches
- Fatigue
- Bone pain
- Episodes of low blood pressure
Some individuals may experience severe allergic-type reactions (anaphylaxis), particularly after triggers such as insect stings, certain medications or temperature changes.
Treatment
Avoidance of known triggers is important. In more severe systemic forms, specialist treatments that target mast cells may be considered. Care is usually coordinated through specialist allergy, haematology or immunology services.
Research and Future Directions
Ongoing research is focused on developing targeted therapies that block abnormal mast cell growth and activation. Clinical trials are assessing new treatments aimed at improving symptom control and long-term outcomes. Improved understanding of genetic drivers is helping personalise treatment approaches.