Results and relevance of critical temperature threshold testing in patients with acquired cold urticaria.

Background Acquired cold urticaria (ACU) is a physical urticaria characterized by local skin reactions after cold exposure. Objective markers of disease severity and activity would be helpful. Unfortunately, such markers are not yet available, even though stimulation time and temperature thresholds are promising candidates. Objectives We assessed and correlated critical temperature thresholds (CTTs) with disease severity and activity in patients with ACU. Methods CTTs were determined in 45 patients with ACU by TempTest-based cold contact stimulation tests (Emo Systems GmbH, Berlin, Germany), and ACU severity and activity were assessed using Likert scales. Results Patients with ACU exhibited mean +/- SEM CTTs of 17 +/- 6 degrees C (range 4-27 degrees C). These thresholds and their changes correlated with the severity (r = 0.53, P < 0.05) and activity of disease (r = 0.64, P < 0.05), respectively. Conclusions These findings indicate that temperature threshold measurements may be used for assessing disease severity and activity as well as the efficacy of therapeutic measures including novel treatment approaches for cold urticaria.