Fast Five Quiz: Chronic Spontaneous Urticaria

William D. James, MD


June 15, 2020

Figure 1. Mast cell releasing histamine

Derangement of mast cell activation and degranulation plays a key role in the pathophysiology of CSU. When mast cells are stimulated, histamine and prostaglandin mediators and cytokines are released, along with other attractants that assist in forming wheals with vasodilation and erythema (hives). This complex interaction leads to a lymphocyte- and granulocyte-mediated hypersensitivity skin reaction.

Histamine release in the lungs and depolarization of neurons are not central to the pathophysiology of CSU. Although lower serum B12 levels have been noted in patients with CSU, vitamin B12 deficiency is neither central to nor associated with the pathophysiology of CSU.

Learn more about the pathophysiology of CSU.


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