Mast Cell Activation Syndrome (MCAS)

Mast Cell Activation Syndrome (MCAS) is a condition where mast cells, a type of white blood cell, release excessive amounts of chemicals like histamine, leading to a range of chronic symptoms. These symptoms can affect multiple body systems and vary in severity and duration. Here are some key points about MCAS:

Symptoms

• Dermatologic: Flushing, hives, easy bruising, itching, and a burning sensation.
• Cardiovascular: Lightheadedness, dizziness, chest pain, arrhythmia, and tachycardia.
• Gastrointestinal: Diarrhea, constipation, cramping, nausea, vomiting, and acid reflux.
• Neuropsychiatric: Brain fog, headaches, fatigue, lack of concentration, and sleep disturbances.
• Respiratory: Congestion, coughing, and wheezing.
• Systemic: Anaphylaxis, which can be life-threatening.

Causes

MCAS can be triggered by various factors, including infections, medications, insect venom, fragrances, stress, exercise, and certain foods. Genetic mutations, particularly in the KIT gene, may also play a role: Symptoms & Treatment.

Diagnosis

Diagnosing MCAS involves identifying repeated symptoms of mast cell activation without a clear trigger, affecting multiple body systems, and showing signs of mast cell activation through tests. Relief of symptoms with mast cell medications also supports the diagnosis: Symptoms & Treatment.

Treatment

Management of MCAS focuses on alleviating symptoms and may include:

• Medications: Antihistamines, mast cell stabilizers, and other medications to control symptoms.
• Lifestyle Adjustments: Avoiding known triggers, stress management, and dietary changes.
• Emergency Care: For severe reactions, carrying an epinephrine auto-injector for anaphylaxis.

MCAS can significantly impact daily life, but with proper management, many people find ways to improve their quality of life.

While MCAS is not autoimmune in nature, it can sometimes be associated with autoimmune conditions. The exact cause of MCAS is not fully understood, but it may involve genetic factors, particularly mutations in the KIT gene.