Anaphylaxis is caused by the immune system. It is a severe allergic reaction where the immune system overreacts to an allergen by releasing a flood of chemicals from mast cells and basophils, such as histamine, that affect multiple body systems including skin, respiratory, cardiovascular, and gastrointestinal systems. This immune response leads to symptoms like bronchial muscle contraction, vasodilation, increased blood vessel permeability, and potentially life-threatening shock.
Explanation of the Body System Involved
- The immune system is responsible for detecting foreign substances (allergens) and responding by producing specific antibodies (IgE).
- Upon exposure to an allergen, these IgE antibodies trigger mast cells and basophils to release inflammatory mediators like histamine.
- These chemicals cause the symptoms of anaphylaxis: airway constriction, blood vessel dilation, fluid leakage, and heart muscle effects.
- Both immunologic (IgE-mediated) and non-immunologic mechanisms (direct mast cell degranulation) can cause anaphylaxis.
Thus, the immune system is the key body system responsible for the cause and mechanism of anaphylaxis.
