Idiopathic cold urticaria and anaphylaxis

Area of Science:

• Immunology
• Dermatology
• Allergy

Background:

• Cold urticaria (CU) is a physical urticaria triggered by cold exposure, causing hives and swelling.
• Diagnosis often involves an ice cube test, but 20% of patients show negative results.

Observation:

• A patient experienced CU and anaphylaxis while swimming and diving in the sea.
• This occurred despite potential negative results on standard diagnostic tests.

Findings:

• The case demonstrates that cold urticaria can lead to severe systemic reactions, including anaphylaxis.
• Generalized cold exposure, like sea swimming, poses a significant risk for patients with CU.

Implications:

• Physicians should consider anaphylaxis risk in CU patients, especially during activities involving significant cold exposure.
• Alternative diagnostic approaches may be needed for CU patients with negative ice cube tests.