Prevalence of hidradenitis suppurativa in a Turkish population: validation of a screening questionnaire in Istanbul, Turkey Dear Editor, Hidradenitis suppurativa (HS) is a chronic inflammatory condition involving abscesses, sinus tracts, and scarring, primarily in intertriginous areas. Emerging typically in the third and fourth decades, HS often leads to significant emotional distress due to stigmatization, reducing the quality of life. The prevalence of HS varies across populations and study designs (0.00033-4.1%). 1 However, epidemiologic HS studies from Turkey are lacking.This study investigates the prevalence of HS in Istanbul, Turkey, validates the HS screening questionnaire, and contributes to the Global Hidradenitis Suppurativa Atlas (GHiSA).