Provocation test on stairs: a new accessible method to cholinergic urticaria diagnosis.

Abstract

Summary: Background. Cholinergic urticaria (CholU) is characterized by itching and/or stinging, painful micro wheals due to systemic heating. There are two standardized protocols to diagnose CholU using an exercise bike with heart rate or warming passive. The objective is to provide an affordable, new, low-tech test to assist the diagnostic. Methods. Cross-sectional study with a convenience sample; 10 with a diagnostic or high suspicion of CholU and 20 participants without suspicion of CholU, recruited in a UCARE from a developing country. After the pre-participation assessment, the provocation test through movements of going up and down a flight of stairs and with a heart rate monitor, an increasing 15 bpm every 5 min until an increase of 90 bpm above the initial level, for 30 min and/or stopped immediately, upon visualization of wheals and with body temperature measured in 3 different locations every 5 min. Results. The group CholU comprised eight females and two males (29.6y), and the other group had eleven females and nine males (27.2y). Data analysis demonstrated that in a positive test in a body temperature measured above 37.05ºC and with a variation of 0.35ºC above the initial value, sensitivity of 80% and specificity of 100% in the forehead region and sensitivity of 80% and specificity of 90% in tympanic region. Conclusions. Thus, with the feasibility of reproducing the method, it is expected that this simple and accessible method for diagnosing CholU can be a tool for application, mainly in developing countries.