Ultra-freeze induced cold contact wheals during cryosurgery: an uncommon subset of acquired cold contact urticaria.

UNLABELLED: Cryosurgery is a safe and effective therapeutic tool for a wide variety of cutaneous and mucocutaneous disorders. Side-effects include transient erythema and oedema. OBJECTIVE: A series of three patients presenting localized contact wheals minutes after contact with liquid nitrogen in the absence of clinical manifestations of cold urticaria is presented. METHODS: Specific cold diagnostic provocation tests with liquid nitrogen challenge test, ice cube test and Tempt-test® were performed. RESULTS: The three patients showed an immediate wheal after cold contact with liquid nitrogen. The ice cube test, the temperature thresholds and the critical stimulation thresholds at 4◦C assessed with the Tempt-test 3.1® were negative. The induced wheals showed pathological features of urticaria. Eight patients suffering from acquired cold urticarial developed also liquid nitrogen induced wheals but none of the healthy controls. CONCLUSION: A peculiar subset of cold urticaria secondary to exposure to ultra-freeze temperatures developing in patients treated with cryotherapy is reported. The concept of "ultra-freeze urticaria" is proposed.