Evaluation of skin barrier function in allergic contact dermatitis and atopic dermatitis using method of the continuous TEWL measurement.

PURPOSE The aim of study was to determine usefulness of the method of continuous TEWL measurement in the evaluation of skin barrier function in physiological conditions and in allergic contact dermatitis (ACD) and atopic dermatitis (AD). MATERIAL AND METHODS Study was conducted on a group of 86 persons: 48 patients with allergic contact dermatitis, 18 with atopic dermatitis and 20 healthy individuals. Measurements of transepidermal water loss were made using custom-constructed device for continuous TEWL measurement. In each person the measurements of TEWL were made 4 times: measurement 0 (baseline)--before occlusion with 1% lauryl sulphate for 24 h, measurement 1-15 minutes after SLS patch removal, measurement 2-30 minutes after measurement 1 and measurement 3-30 minutes after measurement 2. Obtained data were statistically analyzed. RESULTS TEWL ratio values obtained in measurement 0 were as follows in individual groups of patients: 13.20 +/- 8.25 in the AD patients, 10.09 +/- 8.29 in ACD patients and 9.02 +/- 5.99 in control group. Analogous TEWL values in the subsequent measurements were: in measurement 1--16.08 +/- 11.17; 11.63 +/- 6.43; 17.39 +/- 12.41, in measurement 2--23.72 +/- 14.58; 14.71 +/- 6.46; 17.55 +/- 8.25, measurement 3--24.09 +/- 14.93; 16.34 +/- 6.32; 18.44 +/- 8.26. TEWL ratio values were higher in both groups of patients as compared to control group but not statistically significant (p = 0.1778). After 24 h exposition to SLS, TEWL ratio values increased in all examined groups as compared to baseline (0) measurement. All measurements, except for measurement No 1 in AD group of patients, showed statistically significant differences. The highest increase of TEWL values were observed in group of AD patients. CONCLUSIONS Delay in skin reaction to SLS in patients with atopic dermatitis provides evidence for different properties of water barrier of the skin in this group as compared to healthy individuals. Increasing tendency in TEWL values 1 hour after SLS removal might reflect persistent damage to water barrier of the skin by detergent. Method of continuous assessment of water barrier of epidermis, through the possibility of multiple measurement by TEWL in examined periods of time, decreased the risk of mistake and increased accuracy of measurement. Measurement of TEWL values allows for assessment of otherwise unnoticed damage to water barrier of the skin.