[Predictive factors of polysensitization to contact allergens: study conducted at the Dermato-Allergology Unit of the Farhat Hached University Hospital in Sousse, Tunisia]

Introduction

polysensitization is often defined as sensitization to three or more contact allergens. The objectives of our study were to determine the prevalence of polysensitization to allergens patch test and to analyze the factors associated with allergen polysensitization of the European Standard Battery in comparison with cases of oligosensitization.

Methods

this is a retrospective descriptive cross-sectional study that included all patients who had undergone patch tests at the Department of Dermato-Allergology of the Department of Occupational Medicine of University Hospital Center Farhat Hached in Sousse spread over 10 years from January 1, 2009 to December 31, 2018.

Results

in total, we collected 464 cases of contact dermatitis during the study period. The average age of patients was 38.93 ± 12.52 years with a slight female predominance (52.8% of cases). Among all the patients who consulted during the study period (832 patients), 133 patients had positive reactions to 3 or more allergens 16% of patients. Concerning, the associations of the most frequently noted allergens were those of triplet (chromium, cobalt, and nickel) in 15 patients and triplet (mercaptobenzothiazole, thiuram mix, and IPPD) in 7 cases. The predictive factors of polysensitivity were the personal history of leg ulcers; the site of the lesions in the thorax and the erythematous squamous and dyshidrotic appearance of the lesions.

Conclusion

this phenomenon is frequent polysensitization, and close collaboration between dermatologists and occupational physicians to prevent this type of multiple allergies through better management of personal and also professional risk factors.

Patterns of positive patch test reactions to formaldehyde and formaldehyde releasers at the Finnish Institute of Occupational Health from 2007 to 2020

BACKGROUND

Formaldehyde is an important contact sensitizer. Formaldehyde releasing substances induce positive reactions in formaldehyde-allergic patients, but there are also reactions independent of formaldehyde allergy. In an earlier study, stronger formaldehyde reactions led to more positive reactions to quaternium-15.

OBJECTIVES

To analyze patterns of positive patch test reactions to formaldehyde and different formaldehyde releasers.

METHODS

Patch test files of 1497 patients investigated during the period November 2007-August 2020 were retrospectively reviewed for positive reactions to formaldehyde and its releasers. During the study period, almost all (≥99.3%) patients were tested with a formaldehyde dilution series and six formaldehyde releasers.

RESULTS

Ninety-three patients tested positive to formaldehyde; 80% of these had positive reactions to at least one formaldehyde releaser, most often benzylhemiformal. There were only nine independent contact allergies to formaldehyde releasers. There were only two reactions to 2-bromo-2-nitropropane-1,3-diol and they occurred in formaldehyde-negative patients. In patients with extreme (+++) reactions to formaldehyde, concomitant positive reactions to any of the other 11 investigated formaldehyde releasers were more common than in patients with milder formaldehyde reactions.

CONCLUSIONS

Strong formaldehyde reactions were associated with positive reactions to formaldehyde releasers.

Cytotoxicity, haemolymphatic parameters, and oxidative stress following exposure to sub-lethal concentrations of quaternium-15 in Mytilus galloprovincialis

The presence of a xenobiotic in the environment can often represent a risk for living organisms. Quaternium-15, a preservative, is one of the most used substances and is added to several cosmetics and other industrial products. For this reason,kwowing the bio-indicator of the marine environment, the toxicological effects potentially elicited by this preservative on the marine invertebrate Mytilus galloprovincialis were studied. The results of this work confirm that quaternium-15, used at 0.1 and 1mg/l concentrations, while metabolized in M. galloprovincialis, causes a decrease in cellular viability, and remarkable changes to the defense and antioxidant system. In fact, haemocyte viability is dramatically reduced, and haemolymphatic parameter measurements indicate a stress on the animal. Moreover, an increase in radical species production, in Thiobarbituric Acid Reactive Species (TBARS) concentration, and in the Heat Shock Protein 70 amount, were observed in hepatopancreas. These changes suggest that the antioxidant systems are activated to overwhelm the oxidative damage induced by quaternium-15. Quaternium-15 jeopardizes both the defense and antioxidant systems. These results provide essential information with the biological fate of quaternium-15 in aquatic organisms, and confirm that biomarkers represent an important tool for modern environmental assessments as they can help with the prediction of pollutants involved in the monitoring program.

Evaluation of Functionality and Biological Responses of Mytilus galloprovincialis after Exposure to Quaternium-15 (Methenamine 3-Chloroallylochloride)

Although the irritant effects of quaternium-15 have been established, little is known about the toxicological consequences induced by this xenobiotic on aquatic invertebrates. The present article reports toxicological, histological and physiological effects of quaternium-15 following the exposure of Mytilus galloprovincialis for 18 days at three different concentrations (0.1, 1.0 and 2.0 mg/L). The results demonstrate that at higher concentrations histological damages to M. galloprovincialis gills occur, like melanosis, light exfoliations, increase of mucus production and infiltrative inflammation. In addition digestive gland cells of M. galloprovincialis, were not able to perform the regulation volume decrease (RVD) owing to osmotic stress following the exposure to the preservative. Overall, this first study on quaternium-15 highlights that it can jeopardize both the morphology and vital physiological processes in marine invertebrates, depending on the duration of exposure and the concentration of the preservative, indicating that further studies are necessary to increase our knowledge about the effects of this substance, commonly added to our products of daily use.

Patch test results in patients with allergic contact dermatitis in the Podlasie region

INTRODUCTION

The aim of the study was to provide current data on the incidence of allergy to various contact allergens in patients with allergic contact eczema and the analysis of selected socio-demographic data of the patients.

MATERIAL AND METHODS

The study included 1532 patients (1010 women and 522 men) treated for allergic contact dermatitis at the Department of Dermatology and Venereology and at the Dermatology Outpatient Clinic in Bialystok in 2007-2011. The assessment of selected demographic data and skin lesions was based on the MOAHFLA index, while the results of patch tests were analyzed with modified Baseline European Series consisting of 31 allergens.

RESULTS

In the group of patients with eczema, 34.1% were men, and 55% of all respondents were people over 40 years of age. The occupational character of skin lesions was found in 22.5%. Most frequently (38.9%) skin lesions were localized on the hands, rarely involved legs (3.98%). Atopic dermatitis was diagnosed in 4.5% of patients. The ten most frequent allergens were: nickel sulfate (24%), cobalt chloride (15.3%), fragrance mix (8.25%), potassium dichromate (6.8%), balsam of Peru (5.5%), neomycin (4.42%), paraphenylenediamine (3.85%), Quatermium-15 (2.1%), detreomycin (1.83%) and budesonide (1.44% of tested patients).

CONCLUSIONS

Frequent allergy to detreomycin indicates the need of patch testing for this allergen of all examined patients with allergic contact dermatitis. The increased frequency of the nickel allergy is a worrying problem and indicates the need for education about the risk factors for nickel allergy development and the implementation of appropriate legal regulations.