Understanding the etiology and pathogenesis of hidradenitis suppurativa

The “hidradenitis” in hidradenitis suppurativa means inflammation of apocrine glands, but it took more than 100 years to realize that was a misnomer and that it is actually a disease of hair follicles, Porter explains. Understanding of the pathogenesis has largely followed clinical trial development, she said. Interleukin-17 is now thought to be a key driver. Follicular occlusion from hyperkeratosis and immune dysregulation are central to pathogenesis, with some signaling pathways more involved in early nodules and others in later tunneling, Porter notes. Recent large genome-wide association studies have identified genes, such as SOX9 and KLF5, that might be involved in the causation.