Transepidermal Water Loss Levels Research Articles

THE FUNCTIONAL STATUS OF THE SKIN BARRIER IN CHILDREN WITH ATOPIC DERMATITIS

Introduction. One of the factors in the pathogenesis of atopic dermatitis is a dysfunction of the skin barrier. Background. To reveal the features of the barrier function of the skin in children with atopic dermatitis by measuring transepidermal water loss (TEWL) and the pH of the skin. Methods. The study included 98 children with atopic dermatitis. All patients measurement was performed by TEWL (Tewameter TM 300, Multi Probe Adapter MPA 5/9, Courage + Khazaka) and the pH of the skin (Skin-pHMeter, Multi Probe Adapter MPA 5/9, Courage + Khazaka). Results. TEWL value was significantly higher in children with severe atopic dermatitis (p=0,00001), in children up to 3 years (p=0,002), in patients with skin colonization of Staphylococcus aureus (p=0,006) and with specific IgE to staphylococcal enterotoxins. Skin pH was significantly higher in children with severe atopic dermatitis (p=0,0001), and in children under the age of 3 years (p=0,04). Conclusion. The determination of the level of TEWL and skin pH to assess the degree of inflammation activity in atopic dermatitis and to justify use of topical therapy, aimed to restoring the epidermal barrier of the skin at children with atopic dermatitis, is substantiated.

PREVENTION OF HAND DERMATOSES IN SMALL CATERING ENTERPRISES

Work in catering and food processing is mostly performed by hands. Mechanical, thermal and chemical agents, as well as damp working conditions and frequent hand washing aggravate skin irritation. The aim of the study was to test the efficacy of hydrophobic skin protection measure at these workplaces. We recommended the prevention of contact skin disorders by using hydrophobic skin protection measure. The study was conducted in a group of 20 food service sector workers, They were interviewed about skin problems and skin protection measures. Tolb assess the effect of the protective preparation on the skin dermatological test procedures, corneometry and sebumetry, were applied, as well as the level of transepidermal water loss (TEWL) was measured. The same survey was performed in the control group composed of 10 workers who used and 10 who did not use barrier preparation. The respondents declared dryness, roughness, peeling, burning, redness, erythema of the skin. All who had applied barrier cream observed a significant improvement of the skin hydration increased by about 30%, and lubrication of the skin - by 11 times on average. Also the level of TEWL decreased by about 25%. The improvement of skin conditions and reduction of skin disorders were observed confirming the effectiveness of the protection of the skin from exposure to harmful factors. Knowledge about prevention of skin diseases should be promoted among employees of catering enterprises.

The use of high frequency ultrasound imaging in skin moisturization measurement

The appropriate skin hydration level enables its normal function and healthy appearance. The purpose of present research was to assess the applicability of high frequency ultrasound (HFU) to the monitoring of skin moisturization treatments. The study sample encompassed 27 women, aged 20-67 y.o. (mean age of 45.48 y.o.) with dry skin. All women applied a strong moisturizing cream on their facial skin for 14days. The course of treatment was monitored using the HFU. The following parameters were subjected to the ultrasound evaluation: epidermal echo thickness, dermis thickness, and separately the thickness of the superior and inferior layer of dermis. The measurements were taken on the participants' chins and cheeks. In addition, skin hydration and transepidermal water loss (TEWL) were determined. Statistically significant differences were obtained between the echogenicity of the superior layer of the dermis on the chin and cheek. After treatment, the statistically significant values of TEWL decrease and hydration increase were obtained on the cheek skin. No statistically significant differences between the TEWL or hydration levels were found on the chin. No statistically significant differences between the epidermal echo and dermis thickness values for the two measurement points were observed. The HFU is a useful method for the monitoring of skin moisturization treatments.

Inhibitory Effect ofNelumbo nucifera(Gaertn.) on the Development of Atopic Dermatitis-Like Skin Lesions in NC/Nga Mice

Atopic dermatitis (AD) is a chronic inflammatory skin disease which has a complex etiology that encompasses immunologic responses. The study was carried out to examine the effect of Nelumbo nucifera (Gaertn.) leaf (NL) on the AD-like skin lesion induced by repeated epicutaneous application of 2,4-dinitrochlorobenzene (DNCB) on the dorsal skin of NC/Nga mice. Three different doses of NL (5, 25, and 50 mg/mice/day) were administered orally from the day of sensitization with DNCB for 4 weeks. The efficacy of NL was judged by histopathological examination, blood IgE level, measurement of transepidermal water loss (TEWL), scratching behavior, and skin severity score. NL resulted in the suppression of clinical severity score, TEWL, scratching behavior, and blood IgE level. Histopathologic analyses revealed that thickening of the epidermis and mast cell degranulation was significantly reduced in NL group. These results suggest that NL may be a useful natural resource for the management of AD.

Anti-inflammatory effects of sacran, a novel polysaccharide from Aphanothece sacrum, on 2,4,6-trinitrochlorobenzene–induced allergic dermatitis in vivo

BackgroundSacran is a newly discovered sulfated polysaccharide extracted from an algae, Aphanothece sacrum, grown in a river of the Kyushu region in Japan. ObjectiveTo evaluate sacran's inhibitory effect in 2,4,6-trinitrochlorobenzene (TNCB)–induced allergic dermatitis in NC/Nga mice. MethodsSacran was extracted by acid and alkaline treatment of A sacrum cyanobacterial biomaterials. To sensitize mice, 150 μL of 5% TNCB was applied epicutaneously on the abdomen of each mouse on day 1 and challenged with 15 μL of 1% TNCB applied on the ear skin of mice on day 8 and then every other day to induce skin lesions. Serum levels of inflammatory markers were measured and histopathologic examination of ear skin specimens performed. On the other hand, sacran's transepidermal water loss was evaluated in 11 volunteer women with dry skin. ResultsEpicutaneous application of sacran in mice has significantly inhibited the development of allergic dermatitis skin lesions and reduced the number of scratching behavior episodes (P < .01). In addition, sacran efficiently inhibited IgE (P < .001), tumor necrosis factor α (P = .02), interleukin 4, interleukin 5, and interferon γ (P < .01; vs buffer in the TNCB group) production and eosinophilic infiltration in the chemical allergen–exposed ear skin. In addition, sacran-treated body regions of human volunteers with dry skin significantly reduced transepidermal water loss levels compared with exogenous hyaluronic acid (P < .01), which is known to improve skin moisture and exert skin barrier repair activity. ConclusionsThis study suggests that sacran exerts anti-inflammatory effects by improving skin barrier function and reducing TH2 cytokine production.

Defective barrier function in melasma skin

Melasma is characterized by increased pigmentation and photodamaged features, which include solar elastosis. Recently, we detected the downregulation of the genes most associated with lipid metabolism using microarray analysis in melasma. These findings suggested that lesional skin may have different biophysical characteristics, and, in particular, an altered skin barrier function. To determine the cutaneous biophysical characteristics of melasma. The melanin index, erythema index, stratum corneum hydration, sebum content and transepidermal water loss (TEWL) were measured for lesional and perilesional normal skin of 16 melasma patients and then compared. In addition, a skin biopsy was performed on 11 of the 16 study subjects to measure stratum corneum thickness and to study the protein expressions of PPAR-α and ALOX15B. Melanin index, erythema index and stratum corneum hydration were significantly higher in lesional skin than in perilesional normal skin. No significant difference was found between lesional and normal skin in terms of basal TEWL level or sebum content. However, the rate of TEWL after barrier perturbation was significantly higher for lesional skin, and the barrier recovery rate was significantly delayed. Furthermore, a trend towards thinned stratum corneum was observed for lesional skin, and this was correlated with barrier recovery rate. The expressions of PPAR-α and ALOX15B were variable in the samples. Melasma skin is characterized by impaired stratum corneum integrity and a delayed barrier recovery rate.

Efficacy of Combined Peroxisome Proliferator-Activated Receptor-α Ligand and Glucocorticoid Therapy in a Murine Model of Atopic Dermatitis

Although topical glucocorticoids (GCs) display potent anti-inflammatory activity in inflamed skin, they also can exert numerous harmful effects on epidermal structure and function. In contrast, topical applications of ligands of peroxisome proliferator-activated receptor-α (PPARα) not only reduce inflammation, and also improve cutaneous barrier homeostasis. Therefore, we examined whether sequential topical GCs followed by topical Wy14643 (a ligand of PPARα) might be more effective than either alone for atopic dermatitis (AD) in a hapten (oxazolone)-induced, murine model with multiple features of AD (Ox-AD). Despite expected anti-inflammatory benefits, topical GC alone induced: i) epidermal thinning; ii) reduced expression of involucrin, loricrin and filaggrin; and iii) allowed outside-to-inside penetration of an epicutaneous tracer. While Wy14643 alone yielded significant therapeutic benefits in mice with mild or moderate Ox-AD, it was less effective in severe Ox-AD. Yet, topical applications of Wy14643 after GC was not only significantly effective comparable to GC alone, but it also prevented GC-induced structural and functional abnormalities in permeability barrier homeostasis. Moreover, rebound flares were largely absent after sequential treatment with GC and Wy14643. Together, these results show that GC and PPARα ligand therapy together is not only effective but also prevents development of GC-induced side effects, including rebound flares, in murine AD.

Intestinal absorption of dietary maize glucosylceramide in lymphatic duct cannulated rats

Sphingolipids are ubiquitous in all eukaryotic organisms. Various physiological functions of dietary sphingolipids, such as preventing colon cancer and improving the skin barrier function, have been recently reported. One of the common sphingolipids used as a foodstuff is glucosylceramide from plant sources, which is composed of sphingoid bases distinct from those of mammals. However, the fate of dietary sphingolipids derived from plants is still not understood. In this study, we investigated the absorption of maize glucosylceramide in the rat intestine using a lipid absorption assay of lymph from the thoracic duct. The free and complex forms of trans-4,cis-8-sphingadienine, the predominant sphingoid base of maize glucosylceramide, were found in the lymph after administration of maize glucosylceramide. This plant type of sphingoid base was detected in the ceramide fraction and N-palmitoyl-4,8-sphingadienine (C16:0-d18:2) and N-tricosanoyl-4,8-sphingadienine (C23:0-d18:2) were identified by LC-MS/MS. The cumulative recovery of 4t,8c-sphingadienine in the lymph was very low. These results indicate that dietary glucosylceramide originating from higher plants is slightly absorbed in the intestine and is incorporated into ceramide structures in the intestinal cells. However, it appears that the intact form of sphingoid bases is not reutilized well in the tissues.

Induction of eosinophil‐ and Th2‐attracting epidermal chemokines and cutaneous late‐phase reaction in tape‐stripped skin

Skin barrier damage induces various harmful or even protective reactions in the skin, as represented by enhancement of keratinocyte cytokine production. To investigate whether acute removal of stratum corneum modulates the production of chemokines by epidermal cells, we treated ears of BALB/c and C57BL/6 mice by tape-stripping, or acetone-rubbing as a control of acute barrier disruption procedure. There was no difference between the tape-stripped and acetone-rubbed skin sites in the increased and recovered levels of transepidermal water loss. The mRNA expression levels of all the chemokines tested, including Th1 chemokines (CXCL10, CXCL9 and CXCL11), Th2 chemokines (CCL17 and CCL22) and eosinophil chemoattractant (CCL5), were higher in the epidermal cells from BALB/c than in those of C57BL/6 mice. In particular, CCL17, CCL22 and CCL5 were remarkably elevated in BALB/c mice and augmented by tape-stripping more markedly than acetone-rubbing, whereas Th1 chemokines were enhanced by acetone-rubbing more remarkably. Tape-stripping induced dermal infiltration of eosinophils in BALB/c but not C57BL/6 mice. In a contact hypersensitivity model, where BALB/c mice were sensitized on the abdomen and challenged on the ears with fluorescein isothiocyanate, mice exhibited higher ear swelling responses at the late-phase as well as delayed-type reactions, when challenged via the tape-stripped skin. The challenge via tape-stripped skin augmented the expression of IL-4 and CCR4 in the skin homogenated samples, indicating infiltration of Th2 cells. These findings suggest that acute barrier removal induces the expression of Th2 and eosinophil chemokines by epidermal cells and easily evokes the late phase reaction upon challenge with antigen.

Skin barrier function recovery after diamond microdermabrasion

Microdermabrasion is a popular method for facial rejuvenation and is performed worldwide. Despite its extensive usage, there are few publications on skin barrier change after microdermabrasion and none concerning diamond microdermabrasion. Our object was to see changes in transepidermal water loss (TEWL), hydration and erythema of the face following diamond microdermabrasion. Twenty-eight patients were included in this spilt face study. TEWL, stratum corneum hydration and the degree of erythema were measured from the right and left sides of the face (forehead and cheek) at baseline. One side of the face was treated with diamond microdermabrasion and the other side was left untreated. Measurements were taken right after the procedure and repeated at set time intervals. Diamond microdermabrasion was associated with a statistically significant increase in TEWL immediately after the procedure and at 24 h. However, on day 2, levels of TEWL were back to baseline. An increase in hydration and erythema was observed right after microdermabrasion, but both returned to baseline on day 1. The results show that skin barrier function of the forehead and cheek recovers within 2 days of diamond microdermabrasion. Diamond microdermabrasion performed on a weekly basis, as presently done, is expected to allow sufficient time for the damaged skin to recover its barrier function in most parts of the face.

Dermonutrition and akin care: the Essensis®case

The skin is an outward sign of inner health and well being. Providing protection is certainly one of the most important function of the skin functions. As a protective barrier, the skin must prevent water loss and protect against pathogen and foreign substances entering the body. One of the primary layers that provide this protection is the stratum corneum (SC). Lifestyle changes such as ageing, and environmental factors, in particular cold weather, can impair the functioning of this barrier through alterations to the composition of the lipids which make up the SC. Under such circumstances, transepidermal water loss levels may be elevated and the natural moisture barrier may be more susceptible to irritation or to the development of dry skin. It is now well established that good skin condition is dependent upon nutrients in the diet. Interestingly some nutritional factors could help to improve skin barrier such as fatty components (fatty acids, vitamin E) that helps to improve the natural moisture barrier of the skin and or keratinocyte cellular differentiation which in vitro improve SC barrier function. Essensis is a fermented dairy product specifically formulated with borage oil, green tea extract and vitamin E to improve skin barrier function as part of a healthy diet. Essensis addresses the healthy population – globally and from a dermatological perspective.

Oral Intake of Glucosylceramide Improves Relatively Higher Level of Transepidermal Water Loss in Mice and Healthy Human Subjects

We examined the effect of oral intake of pure glucosylceramide derived from konjac extract on skin barrier function evaluated by transepidermal water loss (TEWL) in hairless mice with sodium dodecyl sulfate (SDS)induced skin roughness. The difference of TEWL between SDS-treated site and untreated sites in the pure glucosylceramide-fed group was significantly lower than that in control group on day 14 of ingestion. We investigated interleukin-1α (IL-1α )p roduction in the hairless mouse skin, and it was significantly lower in the glucosylceramide-fed group than that of control animals. This reduced IL-1α production should contribute to improvement of skin barrier function. To investigate the effect of oral intake of glucosylceramide in human, we conducted a randomized double-blind placebo-controlle ds tudy including 100 healthy subjects whose TEWL in cheek was relatively high. As a result, cheek TEWL was significantly lower in the test product group as compared with the control group in weeks 8 and 12 of ingestion (p =0 .023 and p =0 .002 respectively).

Effect of Ingested Concentrate and Components of Sake on Epidermal Permeability Barrier Disruption by UVB Irradiation

Daily topical applications of the concentrate of sake (CS) have been shown to reduce epidermal barrier disruption in murine skin caused by ultraviolet B (UVB) radiation, while one of the components of sake, ethyl alpha-D-glucoside (alpha-EG), also reduces barrier disruption. We confirmed the effect of oral ingestion of various doses of CS on epidermal barrier disruption caused by UVB irradiation in hairless mice. Then, to identify the effective components, we quantitatively analyzed alpha-EG, organic acids, and glycerol, the main components of CS, and examined the effect of various concentration of each on barrier disruption. alpha-EG and organic acids showed comparable results to CS itself, and transepidermal water loss levels in murine skin were significantly decreased as compared with the control. Furthermore, an investigation of the dose dependency of these agents was performed and the results showed the significant effectiveness of alpha-EG. In addition, red wine concentrate (WC) and beer concentrate (BC) were examined in order to confirm the unique effects of CS. Similar effects were not found with WC and BC.

FS07.6 Efficacy of UVB radiation versus skin protection in the prevention of hand dermatitis in baker apprentices

In‐vitro and in‐vivo data suggest the efficacy of various skin protection measures in the prevention of hand dermatitis (HD). The aims and objectives of this intervention study was to quantify the efficacy of skin protection (SP) measures and UVB hardening in the prevention of HD. SP measures were compared against UVB hardening in a controlled clinical trial of 94 apprentices. The apprentices were assigned to the intervention arms class‐wise. Baker apprentices involved in a previous follow‐up study served as an additional historic control group representing no intervention. The apprentices were interviewed and examined in a standardised way at the beginning of the vocational training and at four follow‐ups. Transepidermal water loss (TEWL) was measured at the back of the hands. Point prevalence of HD in the groups after 6 months was highest in the controls (C)(29.1%) followed by the UVB‐group (19.4%) and the SP group (13.3%). UVB hardening and SP measures were associated with a reduction in HD prevalence by 9.7%(95%CI −8.5 to 28.1) and 15.8%(95%CI −2.4 to 33.9), respectively. Unadjusted logistic regression analysis showed atopy (OR = 4.74, 95%CI 1.12–20.11, p = 0.035) and skin care (OR 0.39, 95%CI 0.16–0.86, p = 0.023) to be independent risk factors. Application of SP measures reduced the OR for HD 0.8 (95%CI 0.17–3.70) and 0.33 (95%CI 0.09–1.23) fold compared to the UVB and C group, respectively. The trends in the clinical results were confirmed by statistically significant differences in TEWL values. Apprentices in the SP group consistently had a lower prevalence of HD compared to the apprentices in the UVB and C group. These trends were reinforced by statistically significant differences in TEWL levels. A multi‐centre trial is recommended to confirm the efficacy of SP measures in a larger randomised study.

Vehicle-controlled effect of urea on normal and SLS-irritated skin

It is known that, depending on the concentration, treatment with urea could improve skin barrier function, despite its penetration-enhancing properties. This controversial skin effect of urea has been explored systematically in this study in terms of the effect of vehicle on the performance of urea. In the first part, a series of four semi-solid emulsions with 5% (w/w) urea, varying in the type of emulsion, nature of emulsifier and polarity of oil ingredients, have been evaluated with regard to their skin hydrating and transepidermal water loss (TEWL)-modifying properties. Placebo samples were tested alongside the urea-containing ones. Two best performing moisturisers from the above were chosen for the second part of the study, in which sodium lauryl sulphate (SLS)-irritated skin was treated with both placebo and urea-containing samples. In addition to TEWL and skin hydration level, the erythema index (EI) was measured before, during and after the treatment. The results have shown that barrier-improving and hydrating abilities of urea are bi-directional and dependent on both the type of vehicle used for its delivery and the state of skin.

Lasers and Microdermabrasion Enhance and Control Topical Delivery of Vitamin C

The objective of this study was to evaluate the ability of lasers and microdermabrasion, both of which are skin resurfacing modalities, to enhance and control the in vitro skin permeation and deposition of vitamin C. The topical delivery of magnesium ascorbyl phosphate, the pro-drug of vitamin C, was also examined in this study. All resurfacing techniques evaluated produced significant increases in the topical delivery of vitamin C across and/or into the skin. The erbium:yttrium-aluminum-garnet (Er:YAG) laser showed the greatest enhancement of skin permeation of vitamin C among the modalities tested. The laser fluence and spot size were found to play important parts in controlling drug absorption. An excellent correlation was observed in the Er:YAG laser fluence and transepidermal water loss, which is an estimation of skin disruption. Permeation of magnesium ascorbyl phosphate was not enhanced by the Er:YAG laser. The CO2 laser at a lower fluence promoted vitamin C permeation with no ablation of the stratum corneum or epidermal layers. Further enhancement was observed with the CO2 laser at higher fluences, which was accompanied by a prominent ablation effect. Microdermabrasion ablated the stratum corneum layers with minimal disruption of the skin barrier properties according to transepidermal water loss levels. The flux and skin deposition of vitamin C across microdermabrasion-treated skin was approximately 20-fold higher than that across intact skin. The techniques used in this study may be useful for basic and clinical investigations of enhancement of topical vitamin C delivery.

Allergy and irritation: an adverse association in patients with atopic eczema.

The pathomechanism of atopic eczema is complex. Two of the most important exogenous factors for atopic eczema are allergenic and irritant substances. In this study we investigate the combined effect of topical aeroallergens and irritation on the skin of atopic individuals. We performed patch testing with several aeroallergens (atopy patch test) and with an irritant, sodium lauryl sulphate, on clinically unaffected skin of 30 sensitized patients with atopic eczema. Application was conducted alone and as a consecutive application. Healthy volunteers served as controls. Evaluation was made by measurement of transepidermal water loss 2 h after removal of the patches. In atopic patients, we found increased levels of transepidermal water loss induced by the aeroallergens as well as by sodium lauryl sulphate. The most impressive barrier disruption was seen after application of house dust mite, followed by cat dander and grass pollen. However, the consecutive application of aeroallergens and sodium lauryl sulphate led to a highly pronounced increase in transepidermal water loss. Hence, in sensitized atopic subjects the combined effect of aeroallergens and detergents may cause severe skin problems, and this may be relevant in daily practice.

Tape stripping and sodium dodecyl sulfate treatment increase the molecular weight cutoff of polyethylene glycol penetration across murine skin.

Prior studies in hairless mice have demonstrated that acute barrier disruption by acetone treatment increases the molecular weight (MW) cutoff of polyethylene glycol (PEG) penetration through the skin. The objective of the present study was to further investigate the dependence of permeability on MW with different forms of barrier disruption. A series of PEGs ranging in MW from near 300 to over 1000 Da were used to study the effects of tape stripping and sodium dodecyl sulfate (SDS) treatment on the MW permeability profiles of mouse skin in vitro. The 12-h percutaneous penetration of all the PEG 300, 600, and 1000 oligomers generally increased as a function of transepidermal water loss (TEWL) of the skin, either tape-stripped or SDS-treated. In addition, the total penetration of PEG oligomers across control skin, and skin tape-stripped and SDS-treated to different degrees of barrier disruption progressively decreased with increasing MW. There were no significant differences in the percutaneous penetration of the PEG oligomers between skin tape-stripped and SDS-treated to the same degree of barrier disruption. The penetration enhancement relative to control skin was more prominent with larger molecules. The MW cutoff for skin penetration increased with the degree of barrier disruption irrespective of the treatment applied, and was 986 Da (tape stripping) and 766 Da (SDS treatment) at TEWL levels in the range 10-20 g/m(2) per h in comparison with 414 Da for control skin. In accordance with previous findings in acetone-treated mouse skin, the results strongly suggest that, irrespective of the form of barrier disruption applied, not only higher amounts but also more varieties of chemicals (larger molecules) may penetrate skin with a compromised barrier than normal skin.

Emollients and the response of facial skin to a cold environment.

It is debated whether the use of emollients, in cold weather, constitutes a protective factor or a risk factor for frostbite. To compare the effects of two emollients [oil in water (O/W) and petrolatum] on facial skin in response to cold exposure. Fifteen volunteers participated in the experiment, consisting of 60 min in a cold room (-5 degrees C), preceded and followed by 30 min of acclimatization at room temperature. In the cold room, O/W was applied on one cheek and petrolatum on the other. The cheeks were exposed to wind, produced by a fan, to cool further the skin by the wind chill index. Skin temperature, redness, and transepidermal water loss (TEWL) were measured on both cheeks. Facial skin treated with O/W was significantly colder (up to 1.3 degrees C) than facial skin treated with petrolatum, but the difference disappeared within 20 min. Agreement between temperature measurements and subjective thermal sensations was poor (Cohen's kappa = -0.13). At no point did the paired skin redness and the paired TEWL values vary significantly. The TEWL levels were significantly lower 30 min after the cold exposure than before, but had reached pre-exposure levels the following day. This study demonstrates that for a duration exposure of 20 min, facial skin treated with O/W achieves a lower temperature than facial skin treated with petrolatum. The two emollients had in all other aspects the same effect on the response of facial skin to cold.

Measurement of Electrical Current Perception Threshold of Sensory Nerves for Pruritus in Atopic Dermatitis Patients and Normal Individuals with Various Degrees of Mild Damage to the Stratum corneum

Background: Patients with atopic dermatitis (AD) are well known to be sensitive to irritation from the environment due to the impaired function of the stratum corneum (SC). Electrical current perception threshold (CPT) evaluation quantifies the sensory threshold to transcutaneous electrical stimulation of the sensory nerves. Objective: To study the CPT in a noninvasive fashion using Neurometer^® CPT/C, together with measurements of various functions of the SC. Methods: We measured the CPT on the flexor forearm and cheek of AD patients and normal individuals. Subsequently, we evaluated the CPT and skin sensitivity to a 30% aqueous solution of lactic acid after the infliction of various mildly disruptive measures on the SC on the flexor forearm of healthy individuals by the following three methods: (1) removal of the superficial sebum with acetone/ether, (2) scarification with a needle and (3) tape stripping of the SC. Finally, we examined the effect of topical applications of emollients such as petrolatum or a moisturizing cream to the scratched skin. Results: AD patients showed a lower barrier function and lower CPT than normal individuals. In subsequent studies conducted in normal individuals, the CPT was found to be inversely correlated with transepidermal water loss (TEWL) levels after tape stripping. However, most of all, the partial superficial scarification with a needle decreased the CPT and increased the lactic acid stinging response. Prolonged removal of lipids from the SC with acetone/ether for 30 min that increased the TEWL levels for only 1 day decreased the high-frequency conductance value for 2 days and the CPT only on the 2nd day after treatment. Topical applications of emollients were effective to prevent the increased sensitivity caused by scratching. Conclusions: AD patients showed functional abnormalities of the SC and tended to have more sensitive skin on the cheek and flexor forearm than healthy controls. Even focal SC damage caused by superficial cracking may lead to further disruption of the already damaged SC in AD patients, by eliciting scratching and facilitating the permeation of various environmental allergens and also the induction of hypersensitive skin.