Pesticide Exposure as a Risk Factor for Pemphigus Vulgaris: Findings from a Case-Control Study conducted in Liguria, Italy

Background Pemphigus vulgaris (PV) and bullous pemphigoid (BP) are rare autoimmune bullous diseases (AIBDs) of unknown aetiology. Genetic and environmental factors have been described as triggers of autoimmunity. The latter include exposure to pesticides and industrial pollutants.Objectives To investigate the incidence of AIBDs in Liguria, northern Italy, and to assess the association between exposure to pesticides and working in agriculture and AIBDs.Methods We conducted a retrospective observational study of the incidence of AIBDs in the Liguria region between 2014 and 2024. We also conducted a retrospective case-control study of patients in the province of Imperia, where the highest incidence of AIBDs was found, using a questionnaire to assess exposure to environmental and occupational risk factors.Results The mean annual incidence of AIBDs (PV, 0.026 cases per 1000 inhabitants; BP, 0.102 cases per 1000 inhabitants) in Liguria was higher than the European average. In Imperia, the incidence of BP was significantly higher than the overall Ligurian incidence (P = 0.002). The retrospective case-control study found that exposure to pesticides in domestic settings and having worked in agriculture were associated with a higher risk of developing PV.Conclusions The present study suggests and supports an association between pesticide exposure and the development of PV.Environmental factors, including exposure to pesticides and industrial pollutants, have been described as triggers of autoimmunity. Using a retrospective observational study and a retrospective case-control study, we sought potential associations between exposure to pesticides, working in agriculture and the development of the rare autoimmune bullous diseases pemphigus vulgaris (PV) and bullous pemphigoid in the Liguria region in northern Italy. Our findings suggest and support an association between exposure to pesticides and the development of PV.