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Notes: Summary Background Frequent bathing leads to a skin barrier damage with various changes in physiological skin parameters. Conversely, ultraviolet (UV) irradiation may improve the impaired skin barrier by reducing inflammatory reactions. Objectives The aim of this study was to investigate the changes of physiological skin parameters during a therapy with 8-methoxypsoralen (8-MOP) bathing and subsequent UVA irradiation. Methods Thirty patients with a skin disease without barrier disruption were treated with daily bathing in a 8-MOP solution (0·0005%) and subsequent UVA irradiation. Multiple physiological skin parameters (transepidermal water loss, skin blood flow, skin colour, sebum content, skin hydration) were measured repeatedly on clinically non-affected skin on the back, forearm and forehead. In addition, patch testing with sodium lauryl sulphate (SLS) (0·5%) was performed on the forearm and on the back. Results We found a moderate but significant disturbance of skin barrier and hydration on the forearm and the back (bathing + irradiation) after increasing dosages of therapy. In addition, SLS testing leads to stronger reactions. Conclusions We conclude that on clinically healthy skin the impairment of skin barrier by frequent bathing cannot be completely compensated by subsequent UVA irradiation. When conducting a treatment with 8-MOP bathing and UVA irradiation a concomitant therapy supporting the recovery of skin barrier, e.g. with moisturizer, should be performed.

Notes: Background  After using cosmetics, Japanese women frequently complain about sensitive, stinging skin. We wondered whether Japanese women's skin is more sensitive than that of Caucasians.Objectives  To examine possible racial differences of skin irritation and subjective sensations.Methods  We performed patch testing on the forearm with sodium lauryl sulphate (SLS) at different concentrations (0·25%, 0·5%) and 24-h exposure time. Skin reaction was evaluated by measurement of transepidermal water loss (TEWL), stratum corneum hydration, sebum secretion, laser Doppler flowmetry (LD), content of melanin and erythema. During a stinging test with 10% lactic acid (applied to one side of the cheeks) the subjects were asked to describe the present intensity of any sensation. We used a Chromameter to measure skin colour before and after application of lactic acid. This study was performed in Marburg, Germany, with healthy Japanese and German women living in Marburg.Results  After SLS testing, we found no significant differences of the barrier function in the stratum corneum, but we found significant subjective sensory differences between Japanese and German women.Conclusions  Japanese women may complain about stronger sensations reflecting a different cultural behaviour rather than measurable differences in skin physiology; however, a faster penetration of SLS in Japanese cannot be excluded.

Notes: Background : Symptoms of irritable bowel syndrome are often cyclical and thus may require repeated rather than continuous therapy. Tegaserod is effective and well-tolerated for irritable bowel syndrome with constipation but data on retreatment are lacking.Aim : To assess whether tegaserod retreatment is as efficacious and well-tolerated as initial treatment in a primary care setting.Methods : This open-label trial was designed to evaluate the effectiveness of tegaserod under real-life conditions. Irritable bowel syndrome with constipation patients received tegaserod 6 mg b.d. for 12 weeks; response was assessed at weeks 4 and 12. Responders (those achieving satisfactory relief for at least 2 of the previous 4 weeks) at weeks 4 and/or 12 entered an 8-week withdrawal period where symptom recurrence was assessed. Patients experiencing recurrence could receive tegaserod 6 mg b.d. for another 4 weeks (retreatment phase) and on completion, could choose to continue tegaserod in a 6-month extension study.Results : A total of 513 patients received initial treatment with tegaserod; 85.0% (436 of 513) responded. 403 responders entered the withdrawal period; symptoms recurred in 83.9% (338 of 403) after a mean of 38 days. Of the 307 patients who subsequently entered retreatment 89.3% (274 of 307) responded. Among patients entering the retreatment period, 269 (87.6%) had responded within the first 4 weeks of initial treatment. Of these, 243 (90.3%) responded to tegaserod retreatment. Adverse events were infrequent and similar during 4 weeks of the initial treatment period (11.1%) and on retreatment (10.4%). The extension study, completed by 188 of 232 (81.0%) patients, demonstrated good long-term tolerability of tegaserod.Conclusions : Irritable bowel syndrome with constipation patients can be successfully treated, and retreated, with tegaserod 6 mg b.d. Tegaserod was well-tolerated during initial and retreatment periods.

Notes: Background  There is evidence that a higher skin susceptibility may induce nonspecific erythematous or weak positive reactions to contact allergens in patch testing.Objectives  To evaluate whether simultaneous application of sodium lauryl sulphate (SLS) along with diagnostic patch tests with contact allergens can provide information regarding skin irritability which may help to discriminate allergic from nonspecific irritant reactions to contact allergens.Methods  Between July 2001 and June 2003, this prospective study collected patch test data of 5971 patients from 19 centres in Germany and Austria in the Information Network of Departments of Dermatology (IVDK). In addition to contact allergens (standard series and eight known ‘problematic’ allergens with a low reaction index and a high positivity ratio: 1,3-diphenylguanidine, amerchol L-101, benzalkonium chloride, benzoyl peroxide, cocamidopropyl betaine, octyl gallate, phenyl mercuric acetate and propylene glycol), patches with SLS 0·5% and 0·25% aq. were applied. Reactions to the allergens and to SLS were analysed at the IVDK data centre. The association between an erythematous or positive reaction to a certain allergen and an irritant reaction to SLS was assessed with logistic regression analysis, at the same time controlling for the influence of age and sex.Results  Of the 29 allergens of the standard series, 23 and 21 gave a higher percentage of nonspecific erythematous reactions in patients with an irritant reaction to 0·25% and 0·5% SLS, respectively, in comparison with SLS-negative patients. All eight ‘problematic’ allergens gave an increased percentage of nonspecific erythematous reactions. Similarly, 22 and 21 allergens of the standard series gave a higher percentage of positive allergic reactions in patients with an irritant reaction to 0·25% and 0·5% SLS, respectively, and seven of the eight ‘problematic’ allergens gave a higher percentage of positive allergic rections (exception: octyl gallate). For most allergens, the markers of skin reaction (reaction index and positivity ratio) were worse in SLS-positive patients. Differences were more pronounced when testing with SLS 0·25% than with SLS 0·5%.Conclusions  Because there is a convincing association between skin irritability (evaluated by SLS test) and the degree of skin reaction to contact allergens, the SLS test may help in deciding whether a doubtful erythematous or weakly ‘positive’ skin reaction should be interpreted as allergic or irritant.

Notes: Background  Tape stripping is a common method for investigating stratum corneum (SC) physiology as well as bioavailability and bioequivalence of topical drugs.Objectives  To investigate the influence of procedures (anatomical site, pressure, pressure duration, tape removal rate) inherent in each stripping protocol on changes in skin physiology.Methods  Tape stripping was performed using tapes on the forearm, forehead and back. On the forearm different pressures (165 and 330 g cm−2), durations of pressure (2 and 10 s), and removal rate (slow and rapid removal) were used. Changes in skin physiology were evaluated by measurement of transepidermal water loss (TEWL) and hydration.Results  A significant influence of all parameters on the TEWL increase as a function of tape strip number was observed. The fastest increase was demonstrated on the forehead, followed by the back and, lastly, the forearm. Rapid removal produced a protracted increase in comparison with slow removal. Pressure for 10 s induced a faster increase in TEWL than 2 s pressure. Likewise, pressure at 330 g cm−2 induced an earlier increase than pressure at 165 g cm−2. Skin hydration was not influenced by the variables tested.Conclusions  Tape stripping results are influenced dramatically by all investigated parameters. A dynamic SC stress test to investigate SC cohesion more closely is proposed based on the present observations.

Notes: Background  Irritant patch testing is often performed as a 24- or 48-h occlusive patch test with low concentrations of sodium lauryl sulphate (SLS).Objectives  The aim of this study was to investigate potential ways to shorten this test procedure and obtain precise test results.Patients and methods  Thirty-six healthy volunteers underwent irritant patch testing with different pretreatments (PT) of the test fields. Occlusive test chambers were applied on the upper back with SLS 0·5%, 1%, 2% and 5% in large Finn Chambers®. The patches were removed after 4 and 24 h, respectively, depending on the concentration used. Test fields were pretreated as follows: PT 0, field without any PT (control); PT 1, prick with lancet; PT 2, prick with test stamp; PT 3, scratch with lancet; PT 4, incision with standardized incision instrument (0·1–0·2 mm depth). Skin reactions were evaluated by transepidermal water loss (TEWL), skin erythema and skin hydration and as well by a visual score (VS) at 4, 24 and 72 h.Results  Our data show an obvious distinction between PT 0–2 and PT 3–4 at all measurement methods. The average TEWL values with PT 3–4 were higher than those with PT 0–2, especially on the 4-h course. This distinction may derive from the shape and size of the skin impairment achieved by PT 3–4, leading to a mechanical barrier disruption. However, SLS may infiltrate directly into deeper skin layers supported by capillarity. Consequently, no or little penetration through the epidermis and interaction with its structures occurs, which is responsible for irritant skin reactions. The SLS dose in the upper skin layers is therefore lower at these PTs. The lower remaining dose of SLS also explains this distinction, especially for the VS. Additionally, there are presumed reactions in deeper layers of the epidermis and dermis at PT 3–4.Conclusions  In summary, all data suggest a different reaction pattern from the classical irritant response. Therefore, application without any PT seems to be best suited for irritancy skin testing, especially for visual assessment. PTs prior to irritant patch testing have been shown to be unjustifiable.

Notes: Background:  The influence of nutrition on the physiological functions of man is well studied. Numerous diseases can be exacerbated by obesity. However, it has not yet been determined whether body weight and body mass index (BMI), as an indicator of a high body fat store, can influence skin sensitivity.Objective:  This study investigates the correlation between body mass index and the epidermal functions, evaluated by bioengineering methods, before and after an irritant patch test with sodium lauryl sulphate (SLS).Methods:  Epidermal functions were evaluated using an evaporimeter, chromameter and laser-Doppler-flowmeter. Patch testing was conducted for 48 h with two different concentrations of SLS (0.25% and 0.5%) on the forearms of healthy volunteers. Measurements were performed 24 h after patch removal.Results:  Obese individuals showed significantly increased transepidermal water loss (TEWL), skin blood flow and skin colour (red) as compared to a control group. However, the degree of skin sensitivity to SLS was not correlated with BMI.Conclusion:  Basal biophysical parameters of the skin are primarily correlated with the BMI. This may be caused by obesity-induced physiological changes, e.g. increased sweat gland activity, high blood pressure and physiological temperature-regulating system. The epidermal barrier function, as evaluated after SLS patch testing is, however, not correlated with a high BMI, indicating a normal skin barrier.