Cold-induced urticaria after black ant bite anaphylaxis.

Area of Science:

• Immunology
• Dermatology
• Allergy

Background:

• Acquired cold-induced urticaria (CIU) is a physical urticaria, typically spontaneous.
• While insect stings (bees, wasps, jellyfish) are known triggers, CIU following a black ant bite is unprecedented.

Purpose of the Study:

• To report the first case of acquired cold-induced urticaria following black ant bite-induced anaphylaxis.
• To emphasize the diagnostic challenges and management strategies for CIU triggered by specific allergens like the black ant.

Main Methods:

• A case report of a 41-year-old female with a history of black ant bite allergy and subsequent anaphylaxis.
• The patient developed generalized hives upon cold exposure days after the bite.
• Management included antihistamines, epinephrine auto-injector, and allergen avoidance.

Main Results:

• The patient experienced acquired cold-induced urticaria symptoms after a black ant bite.
• Symptoms were effectively managed with desloratadine and avoidance measures.
• The black ant (Samsum ant) is a known trigger for allergic reactions in Qatar and the Gulf region.

Conclusions:

• Acquired cold-induced urticaria is a chronic inducible urticaria, with physical triggers accounting for 25% of cases.
• Lack of validated diagnostic tests and immunotherapy for black ant allergy necessitates reliance on detailed patient history.
• Allergen avoidance remains the primary treatment strategy for CIU triggered by specific allergens.