The relation between the localization of foot dermatitis and the causative allergens in shoes: a 13-year retrospective study.

The purpose of this retrospective study was to test whether the initial pattern of clinical presentation of shoe dermatitis could indicate the causative allergen(s) and to estimate the odds on foot dermatitis in patients with a positive patch test versus those with a negative patch-test result. Between 1990 and 2002, 8543 patients were patch tested with the standard series (and additional allergens, if appropriate). Of them, 1168 (14%) had been referred because of foot dermatitis and 474 of these patients (5.5% of the total group) presented a positive reaction to one or more substances related to shoes. We found that 6 standard allergens in the male group and 8 standard allergens in the female group were statistically significant for the shoe dermatitis group. The data showed a relationship between the distribution pattern of the foot lesions and most of the allergens. These results have clinical applications since the gender of the patients and the localization of the foot eruptions can, indeed, indicate what allergen is involved.

Case-control study to identify melanoma risk factors in the Belgian population: the significance of clinical examination.

BACKGROUND: Although numerous studies have evaluated risk factors associated with cutaneous malignant melanoma (CMM), no such study has been carried out in Belgium. OBJECTIVES: To identify individuals who are at high risk of developing malignant melanoma in Belgium, which could enhance the efficacy of screening interventions and avoid unnecessary skin inspections. STUDY DESIGN/SETTING/SUBJECTS: We prospectively included patients who were diagnosed with invasive malignant melanoma between 1998 and 2001 at the Department of Dermatology in a case-control study. Controls were selected from the outpatient dermatology clinic. Participants were interviewed and clinically examined by a dermatologist. We asked questions concerning most known risk factors associated with malignant melanoma such as phenotypical and skin characteristics, and environmental and lifestyle exposures. To adjust for confounding variables and to estimate odds ratios (ORs) and 95% confidence intervals (CIs), a multivariate model was used. RESULTS: Although sunburn in childhood and substantial occupational solar exposure were modestly, but significantly, associated with malignant melanoma risk, clinical examination yielded several stronger risk factors. In a multivariate model, which adjusted for age, gender and skin phototype, phenotypical characteristics such as skin, hair and eye colour were significantly associated with the development of malignant melanoma. In the multivariate model, people with three or more atypical naevi were at more than 10-fold risk of developing a malignant melanoma (> or = 3 atypical naevi; adjusted OR = 11.40, 95% CI = 4.79-17.53) compared to those without an atypical naevus. The presence of one or more palpable naevi on the upper extremities or having solar lentigines increased the odds of developing malignant melanoma at least twofold. CONCLUSIONS: In Belgium, risk factors associated with malignant melanoma appear to be in accordance with previous studies. To assess peoples' risk profile, clinical skin examination is likely to yield the most important sporadic malignant melanoma risk factors. Therefore, focusing screening campaigns on individuals with predefined findings on skin self-examination may increase its efficacy.

Contact allergy to imidazoles used as antimycotic agents.

The present article reviews the literature (up to 1994) on contact sensitivity to imidazoles and presents the results obtained from 15 patients observed at the Contact Allergy Unit in Leuven. The frequency as well as the cross-reaction patterns described are analyzed. Although allergic contact reactions may have been missed in the past (mainly because of problems with the correct choice of vehicle for patch testing), they seem to be relatively infrequent in view of their widespread use. The imidazole derivatives most frequently reported to be allergens are miconazole, econazole, tioconazole, and isoconazole. As far as cross-reactivity is concerned, statistically significant associations were found in the patient data between miconazole, econazole, and isoconazole; between sulconazole, miconazole, and econazole; and also between isoconazole and tioconazole. Patients sensitive to phenylethyl imidazoles (except ketoconazole) needing antimycotic therapy should be advised to use ketoconazole, clotrimazole, bifonazole, or, perhaps, the new flutrimazole. Clearly, non-imidazole antifungals can also be used.

Studies in patients with corticosteroid contact allergy. Understanding cross-reactivity among different steroids.

BACKGROUND AND DESIGN: Most corticosteroid-allergic patients react to several corticosteroids. Irrefutable proof for the existence of cross-reactions is provided by reactions to substances to which the patient has never been exposed. Four groups of cross-reactions have been proposed, and our own observations support this. However, we have found that budesonide, in particular, tends to be involved not only in cross-reactions with corticosteroids of its own group (group B) but also with those of the ester group (group D). To test clinical observations on patients sensitive to corticosteroids and to establish a molecular basis for cross-reactivity patterns, a statistical analysis of our cases and a conformational study of major corticosteroids were performed. RESULTS: Statistically highly significant positive or negative correlations were found for the combination of tixocortol pivalate plus hydrocortisone and hydrocortisone plus budesonide, respectively. This indicates that budesonide and hydrocortisone or tixocortol pivalate detect different groups of corticosteroid-sensitive patients. Moreover, significant positive correlations were found between budesonide and amcinonide, both molecules belonging to the acetonide group C, and also between budesonide and some esters of group D such as hydrocortisone-17 butyrate and alclometasone dipropionate. These clinical observations were fully supported by a conformational analysis of the electronic shape of corticosteroids involved in this study. Groups A, B, and D were found to be highly homogeneous within each group in terms of molecular structures, while significant differences were observed among the groups. The special behavior of budesonide can be fully explained on the base of its unique molecular structure. Finally, molecular characteristics have been defined for each group. This could be useful for the prediction of potential cross-reactions to new corticosteroid molecules. CONCLUSIONS: The statistical analysis confirms that tixocortol pivalate and hydrocortisone contact allergies are definitely associated, while reactions to budesonide are strongly correlated with the reactions to both the acetonide group and the ester group. These clinical observations are fully supported by the conformational analysis of the molecules involved in this study. Tixocortol pivalate and budesonide should certainly be added to the standard series for the detection of patients sensitized to corticosteroids.

A computer system for contact dermatitis: graphical representation of data.

An overview is given of the computer applications we have developed over the last twelve years in the field of contact dermatitis. The dissemination of exposure lists to sensitised individuals and the development of a knowledge-based system are mentioned only briefly. Priority here is given to the explanation of the graphical representation of the patient data collected since 1978 on 12,000 patients referred to three contact dermatitis units. More than a hundred parameters of each patient have been collected in a database. Several graphs are given of these data and are discussed in detail.

Computer assisted monitoring of contact dermatitis patients.

All contact dermatitis patients are told to avoid their specific allergens. As regards topical pharmaceutical agents, however, it is almost impossible for these patients to identify the products that contain their allergens. In order to provide reliable information for these patients, we have designed a computer assisted data system. The CODEX (COntact DErmatitis indeX) system consists of three computer readable files: a Product File containing the complete composition of the pharmaceutical products on the Belgian market that are applied on the skin and the mucous membranes, a Patient File with the patient's anamnesis, and a Literature File with cross-referenced material on contact dermatitis. Each patient is given a list of the products that contain his/her allergen(s). The data bases are analyzed statistically and updated periodically. Cosmetics in general are excluded.