Objective biophysical findings in patients with sensitive skin
The term sensitive skin has been used to describe a clinical phenomenon of hyperreactivity of the human skin, which develops exaggerated reactions when exposed to external factors. The aim of this study was to determine objective biophysical findings in patients with sensitive skin compared to those individuals with nonsensitive skin. Thirty-two patients with sensitive skin and 30 healthy volunteers with nonsensitive skin were studied. The testing methods included in vivo and in vitro tests: epicutaneous testing (Patch tests); measurement of sebum and hydration of the skin; alkali resistance test; stinging test with lactic acid; reaction to aqueous solution of methyl nicotinate 0.5%, 1.4% and acetyl-b-methylcholine chloride 1:1000; pH measurement; dermographism; and measurement of total and specific IgE. Significant results were observed in the measurement of sebum (p < 0.01) and hydration (p < 0.05) of the skin, in the alkali resistance test (p < 0.05), in the vascular reaction to methyl nicotinate (p < 0.01) and to acetyl-b-methylcholine chloride (p < 0.01) and in the skin response to allergens of the European standard (p < 0. 01) and cosmetic series (p < 0. 05). In addition, the subjective findings of stinging test produced significant results (p < 0.001) as was anticipated. Patients with sensitive skin possess very dry skin with low fatness, which leads to a disturbance of the protective skin barrier function. They also present a hyperreaction of the skin blood vessels, increased transcutaneous penetration of water-soluble chemicals, enhanced immune responsiveness, significant decrease of alkali resistance and a heightened neurosensory stimulation.