Johan P. Nater

Evaluation of a self‐administered questionnaire on hand dermatitis

The purpose of the study was to evaluate a sell‐administered questionnaire on hand dermatitis than was developed to identify persons with hand dermatitis in epidemiological studies. A total of 109 nurses were subject to dermatological examination of the hands within 1 month of returning the questionnaire. 2 types of questionnaire diagnoses were made: a ‘symptom‐bused’ diagnosis and a ‘self‐reported diagnosis’. These were compared to the medical diagnosis of hand dermatitis. The prevalence of hand dermatitis in the 12 months before the study, based on the medical diagnosis, was 18.3%. The prevalence according to the symptom‐based diagnosis and the self‐reported diagnosis was 47.7% and 17.4%. respectively. The sensitivity and specificity of the symptom‐based diagnosis were 100% and 64%, respectively. It is concluded that the symptom‐based diagnosis can be used as screening instrument for the detection of cases in large study populations, if followed by dermatological examination of persons with a positive diagnosis. The sensitivity and specificity of the self‐reported diagnosis were 65% and 93%, respectively. It is concluded that the self‐reported diagnosis can be used to obtain a rough estimate of the prevalence, although comparison of prevalence figures between study populations may be distorted due to a difference in reporting of hand dermatitis. The results of the study illustrate the size of the differences in prevalence estimates that may arise as a result of differences in the definition and method of diagnosing hand dermatitis.

Patch tests with fragrance materials and preservatives

179 patients suspected of cosmetic allergy were patch tested with a series of 16 fragrance materials and 9 preservatives. In 67 patients (37.4%), for more of these substances gave positive reactions. In the group of fragrance materials, the largest numbers of positive patch test reactions were seen to isocugenol, oak moss, geraniol, α‐amylcinnamic alcohol, and a mixture of α‐amylcinnamic aldehyde and α‐hexylcinnamic aldehyde.

Reactions in selected patients to 22 fragrance materials

182 patients on the basis of 6 criteria were suspected of suffering from contact sensitization to cosmetics. 77 (42%) gave a positive reaction to one or more of a series of 22 fragrance and flavor raw materials. The hands were most often involved. Cinnamic alcohol, hydroxycitronellal, eugentol, coumarin, and abitol gave the most common positive reactions; less frequent were cinnamic aldehyde, dihydrocoumarin and dimethylcitraconate. Their relevance could not be traced. However, the first 4 substances were the most frequently identified in 79 suspected cosmetics sent in for analysis by the patients or their physicians. The stability of room‐stored petrolatum‐fragrance mixtures should be checked.

Prediction of susceptibility to an irritant response by transepidermal water loss

The roles of the natural permeability of the stratum corneum to water, and the changes in that permeability effected by a single patch test, were investigated as parameters to predict the susceptibility of the skin to repeated exposures of an irritant. One site on the forearm skin of 27 non‐atopic healthy subjects was exposed to a 0.5% concentration of sodium lauryl sulphate by a single occlusive 24‐h patch. Another site was exposed to a twice daily 4‐day repeated occlusive patch with the same irritant solution. The effects were evaluated by transepidermal water loss measurements made prior to the applications (baseline) on day 1 (BASE), following the single 24‐h patch on day 2 (SINGL), and following the 4‐day repeated applications on day 5 (REPET). Individuals with higher BASE had higher SINGL (R= 0.80, P < 0.001) and higher REPET (R= 0.76, P < 0.001). There was also a significant linear correlation between SINGL and REPET (R= 0.63, P < 0.001). Multiple linear regression analysis of results, however, indicated that a high baseline TEWL is a better indication of an individuals increased susceptibility (high REPET) to weak irritants than a high TEWL value following a single 24‐h patch test. Baseline TEWL may therefore be used as a reasonably accurate preliminary “predictive” screening test for susceptibility to irritants.

The influence of repeated exposure to surfactants on the human skin as determined by transepidermal water loss and visual scoring

The purpose of this study was to develop a new model for the induction of chronic irritant contact dermatitis, which would reflect well the conditions of daily practice. Various weak irritant agents were tested for irritating potency on the skin and the sensitivity of transepidermal water loss (TEWL) measurements in the detection of early skin changes was also studied. 10 widely used surfactants and 1 solubilizer were applied to the skin of the forearms of healthy volunteers in aqueous solutions of 12.5 millimoles/1 for 45 min twice daily for 3 weeks. The effect on the skin was evaluated daily by means of TEWL measurements and by a visual scoring system. Each solution caused an increase in TEWL value over time due to the cumulative irritating action on the epidermal barrier. This increase in TEWL was different for the various solutions, resulting in different mean TEWL values on the last day of the experiment. Thus, it was possible to rank the agents according to irritating potency. This ranking order was the same in almost every individual and remained constant during the 3 weeks. In comparison with the visual scoring system, the TEWL measurements were more sensitive in the detection of early changes in the skin.

Baseline transepidermal water loss (TEWL) as a prediction of susceptibility to sodium lauryl sulphate

The rôle of different factors in the susceptibility of the skin to weak irritants was studied by means of multiple linear regression models. The skin of 37 healthy subjects was exposed to a solution of sodium lauryl sulphate of low molarity 2 × daily for 4 days. The condition of the skin was evaluated by transepidermal water loss (TEWL) measurements on the 1st day (before exposure, TEWL1) and on the 5th day of exposure (TEWL5), and by a visual scoring system. The TEWL5 value was strongly related to the TEWL1 value (R = 0.71). The influence of such factors as history of mucosal atopy, history of sensitivity to soap, dry skin, skin type, sex and age on the TEWL5 value was negligible. The baseline TEWL level (TEWL1) might be a reliable indication of an individuals susceptibility to weak irritants.

THE ROLE OF CONTACT ALLERGY IN THE SPECTRUM OF ADVERSE-EFFECTS CAUSED BY COSMETICS AND TOILETRIES

Of 982 female clients of beauticians interviewed, 254 (25.9%) thinned to have experienced adverse reactions to cosmetics and toiletries in the preceding 5 years. Most reactions were caused by skincare products (36.6%), followed by personal cleanliness products (29.5%), eye cosmetics (24.0%), deodorants and antiperspirants (12.6%), and facial make‐up products (8.3%), 150 women were patch tested. In the European standard series, only a few positive reactions were seen to possible cosmetic allergens; fragrance mix (n=3), wool alcohols (n=3), formaldehyde (n = 2), balsam of Peru (n=1), and colophony (n=1). In the cosmetic series, only Kathon CG elicited positive patch test reactions (n = 3), Cosmetic allergy was considered to be “proven” in 3 patients (2.0%), and “possible” in 7 (4.7%). It is concluded that contact allergy is, responsible for a minority (<10%) of all reactions to cosmetics and toiletries, The majority of reactions are due to irritation from personal cleanliness products such as soups, shampoos, bath foams and from deodorants, or worsening of pre‐existing dermatoses such as seborrhoeic dermatitis and acne.

COMPARABILITY AND REPRODUCIBILITY OF THE RESULTS OF WATER-LOSS MEASUREMENTS - A STUDY OF 4 EVAPORIMETERS

A study was made of the comparability and reproducibility of the results of measurements of water loss, both in vitro and in vivo, using 4 Servo Med Evaporimeters (3 single–probe and 1 double–probe instrument). The optimum time for recording transepidermal water loss (TEWL) after the initial application of the probe to the skin (in vivo), and the best technique for optimizing the accuracy of measuring TEWL were determined. An evaporation device with a constant level of water loss was constructed for in vitro studies. The volar aspect of the right forearm skin of one subject was used in vivo. Both in vitro and in vivo measurements showed that there were some differences between the results of 4 of the 5 probes. The other probe was distinctly out of range. For all probes, the reproducibility of results of successive measurements was high. Stabilization of TEWL values was reached for all probes from 30–45 s after their initial application to the skin. It is recommended that TEWL be recorded for a further 30–s period, after the initial stabilization (45 s), and that this be taken as the true value. The manufacturers recommended calibration procedure is based only on adjustments for the standard specified humidities and zero water loss. The importance of incorporating an additional calibration procedure which includes adjustments for an actual standard constant water loss is thus strongly stressed.

The intra‐ and inter‐individual variability and reliability of transepidermal water loss measurements

An analysis of variance wad conducted to estimate the intra‐ and inter‐individual variations in TEWL on the forearms, by sites (8 measurement sites) and by days (10 different days), in 30 non‐exposed healthy individuals. The estimated intra‐ and inter‐individual variations, by sites, were 15.5% and 84.5′V respectively, the sum of the 2 components always being 100%. Was the exclusion of the 2 most distal sites near the wrist, which had significantly higher baseline TEWL values and fluctuations in TEWL, an improvement in the intra‐individual variation was obtained. Thus, of the 6 sites, the estimated, intra‐ and inter‐individual variations were 8.4% and 91.6%, respectively. This finding supports the exclusion of these most distal sites for future investigations. The estimated intra‐ and inlet‐individual variations, by days, were 20.6% and 79.4%, respectively. The low site‐to‐site (8.4%) and day‐to‐day (20,6%) intra‐individual variations, as compared to the large inter‐individual variations of l he same (91.6% and 79.4%), indicate that baseline TEWL is a stable personal characteristic Thus, individuals susceptible to irritant contact dermatitis (ICD). due to occupational exposure, may be reliably characterized by utilizing their baseline TEWL values, for “prediction” of risk in epidemiological field studies.

Transepidermal water loss with and without sweat gland inactivation

The influence of eccrine sweating on transepidermal water loss (TEWL) was investigated. TEWL was simultaneously measured on both forearms, with and without topical inactivation of the eccrine sweat glands by 0.3 ml of 0.5% aqueous scopolamine hydrobromide (HBr), applied under 1 h occlusive patches. The degree of sweat inhibition, after exercise, was measured at 2, 3 and 4 h after patch removal. In 42 out of 44 subjects, complete sweat inhibition (on exercise) was achieved only at 4 h after removal. After a 15‐min rest in a room at 20°C, the pre‐exercise TEWL values (at 4 h) on the treated and untreated sites were not different (P>0.05), in 38 out of 44 subjects. By this rest period, sweating due to slight physical, thermal or even emotional stimuli may be prevented in most subjects. In the other 6 subjects, the pre‐exercise TEWL values (at 4 h) on the untreated site were 1–1.8 g/m2h higher than (P < 0.001) on the treated site, due to emotional sweating Thus, accurate baseline TEWL measurements may only be made after anticholinergic suppression of the sweat glands. In this way, accurate TEWL measurements may be made even outside favourable laboratory conditions, all industrial sites etc., where circumstances are far from ideal. The effect of this agent applied to a skin site previously irritated artificially by a 24‐h occlusive sodium lauryl sulphate (SLS, 0.3 ml, 0.5% aq.) patch, was also investigated in 17 subjects. In all subjects, 4h after removal, sweating (on exercise) was completely inhibited on the scopolamine‐treated site, pre‐irritated with SLS. Systemic side‐effects were not reported from any test subject, under any condition of exposure.