Assessment of Vasomotion of People With Idiopathic Chilblains

Chilblains, also known as perniosis, is a non-freezing cold injury causing painful inflammatory skin lesions. Chilblains typically affect the dorsal feet or hands, causing inflammatory skin lesions that are often painful, and their pathogenesis remains only partly understood. To improve diagnosis and management, it is vital to focus entirely on chilblains and consider the patient-related and environmental factors that characterize this disorder. Because of this, it's critical to investigate the thermoregulatory function, of individuals with idiopathic chilblains while they are exposed to various environmental conditions (cold and neutral environments).

The participants will visit the laboratory three times. The environmental scenarios were randomly allocated for each participant.

The three different environments will be as follows:

1. Thermoneutral environment 22-24°C and 40-50% relative humidity for 15 minutes.
2. Thermoneutral environment of 22-24°C and 40-50% relative humidity, the temperature within the chamber was decreased by 4 degrees every 20 minutes.
3. Thermoneutral environment of 22-24°C and 40-50% relative humidity, the temperature within the chamber was decreased by 4 degrees every 20 minutes. After 80 minutes (the chamber's temperature will be 10°C and 40-50% relative humidity), the investigators increased the chamber temperature to 22-24 °C and 40-55% relative humidity, and the participants remained in the same sitting position for 20 minutes.

All participants had antinuclear antibodies blood testing for a suspected autoimmune disease such as lupus, rheumatoid arthritis, or scleroderma. Participants were provided blood (C-reactive protein and serum Cortisol) before, immediately after, and 24 hours after each trial and urine samples before and following the trials.

Anthropometric data \[self-reported age, self-reported body stature, and body mass (DXA, Lunar, GE Healthcare Boston, Massachusetts, U.S.)\] will be collected at the beginning of the first visit. Investigators recorded the medical history of all the participants. During the study, continuous heart rate and heart rate variability (Polar Team2. Polar Electro Oy, Kempele, Finland), core temperature (telemetric capsules BodyCap, Caen, France), mean skin temperature (wireless thermistors iButtons type DS1921H, Maxim/Dallas Semiconductor Corp., USA), finger temperature, skin blood flow (laser Doppler flow-meter PeriFlux System 5010, Stockholm, Sweden), and tissue oxygenation changes (Near-Infrared Spectroscopy, PortaLite mini, Artinis Medical Systems, Zetten, Netherlands) will be collected. Skin temperature data collected from seven sites (forehead, arm, thigh, hand, foot, tibialis anterior, navel) and will be expressed as mean skin temperature according to the formula of Hardy/Bubois (Tsk = \[0.7 (forehead) + 0.14 (arm) + 0.05 (hand) + 0.07 (foot) + 0.13 (tibialis anterior) + 0.19 (thigh) + 0.35 (navel)\]. Hydration status was assessed using a handheld refractometer (ATAGO Ltd, Tokyo, Japan) and determined as either euhydrated (USG \< 1.020) or dehydrated (USG ≥ 1.020) according to the current guidelines. Questionnaires (thermal sensation scale: -3 = cold; +3 = hot) assessed participants' thermal comfort/sensation and pain.

Eligibility Criteria:
Inclusion Criteria:

* Healthy individuals with and without idiopathic chilblains.

Exclusion Criteria:

* Non-healthy individuals or any underlying connective tissue disorders (particularly: Raynaud syndrome/phenomenon, Systemic Lupus Erythematosus, Scleroderma)