HS Pathophysiology, Diagnosis, and Classification

Hidradenitis suppurativa (HS) develops through a combination of genetic predisposition and environmental exposures, affecting approximately one-third of patients who have a family history of the condition. The disease involves multiple factors, including immune system dysfunction, metabolic influences, mechanical forces in body folds, and altered wound healing responses. Environmental triggers such as dietary factors, viral exposures, and other pollutants can activate the disease process in genetically susceptible individuals, often beginning during adolescence, when hormonal changes occur.

Diagnosis of HS relies primarily on clinical assessment, with practitioners identifying characteristic recurrent lesions in typical locations including the armpits, groin, under the breasts, and buttocks. The examination focuses on identifying inflammatory nodules, abscesses, and draining tunnels, along with signs like comedones, scarring, and discoloration in affected areas. While Hurley staging remains the standard classification system used in clinical trials to determine disease severity, clinicians also utilize outcome measures based on counting specific lesion types to assess treatment response.

Severity assessment extends beyond physical examination to include the substantial impact on patients’ daily functioning, including pain, drainage, odor, and mental health effects. Practitioners evaluate both the extent of tissue destruction and the disease’s effect on quality of life, recognizing that patients with limited physical disease may experience profound social and emotional consequences. This comprehensive approach considers the number of affected body regions, presence of new lesions in different locations, and the overall burden on the patient’s well-being when developing individualized treatment plans.