Defining Fistular Patterns in Hidradenitis Suppurativa: Impact on the Management

BACKGROUND Recent studies suggest that there are different fistular subtypes in hidradenitis suppurative (HS) patients who are associated with variable therapeutic outcomes. OBJECTIVE To describe clinical and ultrasound features that characterize the different fistular patterns in HS and to evaluate the response to medical therapies. METHODS A retrospective study developed by a well-recognized center specialized in HS analyzing both clinical and ultrasound (US) aspects of fistular structures in HS patients was performed. Medical therapy response was evaluated through follow-up visits at Week 24. RESULTS A total of 117 fistulas detected in the skin of 40 patients were evaluated. Four different types of fistulas were described: dermal fistula (Type A), dermoepidermal fistula (Type B), complex fistula (Type C), and subcutaneous fistula (Type D). Fistulas Type A and B showed a complete resolution after 6 months of different medical therapies in up to 95% and 65% of cases, respectively. Contrary to this, fistulas Type C and D showed no significant response after a medical intervention. CONCLUSION The US evaluation seems to play an important role to define these important structures that will help the clinician in elaborating a personalized combined medical and surgical management of the HS patient.