Damage in hidradenitis suppurativa: a narrative review emphasizing the need for a novel outcome measure.

Cutaneous damage caused by hidradenitis suppurativa (HS) is an important contributor to disease burden, independent of active lesions. Outcome measures used to specifically assess damage are becoming commonplace in the assessment of inflammatory diseases. However, no standardized method for assessing HS damage currently exists. The purpose of this study was to review outcome measures in HS that include constructs of both active disease and damage, review damage-specific instruments used in other inflammatory and destructive diseases, and review instruments used to assess scars of various aetiologies. This ultimately provides insight into how attributes of different tools can be applied to develop an outcome measure specific to HS damage. What is already known about this topic? Hidradenitis suppurativa (HS) is a chronic, relapsing, inflammatory skin condition, which causes consequent cutaneous damage and scarring. Damage caused by HS is highly prevalent and an important contributor to its morbidity. Damage is an important component of inflammatory diseases that has proven its utility in a number of outcome measures; however, no standardized method for assessing HS damage currently exists. What does this study add? This narrative review assesses outcome measures used to measure damage in other inflammatory and destructive diseases. Instruments used to assess damage in other diseases can provide a starting point for the development of a damage outcome measure for HS.