Urticaria Cold
Conditions
Brief summary
The investigators subjected 63 patients (39 with typical Cold urticaria and 24 with atypical Cold urticaria ) and 15 healthy controls to TempTest® cold stimulation tests and critical temperature threshold assessments. Blood microcirculation photoplethysmography measurements were performed 5 min before and 10 min after the ice cube on the volar forearm.
Interventions
DEVICECold stimulation tests / critical temperature threshold
ICT was performed following a standard protocol. Briefly, a melting ice cube in thin plastic bag was placed on the volar surface of the patient forearm for 5 min, with macroscopic assessment of the test site 10 min later. TempTest® CSTs were done with TempTest® 4.0 (Courage & Khazaka, Cologne, Germany), which has a single Peltier element (length: 350 mm, width: 2 mm) that provides a continuous temperature gradient from 4°C to 44°C. The use of TempTest® allows for reproducible and standardized cold (and heat) provocation tests and the identification of CTTs. TempTest® CST results were also assessed 10 min after the end of cold exposure.
Sponsors
City Clinical Hospital No.52 of Moscow Healthcare Department
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Cold urticaria
Exclusion criteria
\-
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Photoplethysmography amplitude | 10 min after the end of cold exposure | To compute the blood flow signal, we subtracted slowly time-varying background and frequency components out of the cardiovascular-related range of 0.3-7 Hz. The resulting well-matched, noise-free and intensity-corrected blood flow images are suited for PPG calculation by averaging the intensity pixel values of each frame. The PPG amplitude is proportional to the amount of arterial blood that reaches the visualized skin area and thus characterizes its blood perfusion. It is measured in arbitrary units (AU). We performed photoplethysmographic assessments of the volar forearm of all patients 5 minutes before and 10 minutes after the beginning and end of ice cube application. |
Countries
Russia
Outcome results
None listed