[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.