Managing Tunneling HS and Screening for Comorbid Crohn's Disease

The next episode in this series, "Managing Tunneling HS and Screening for Comorbid Crohn's Disease," has the panel weighing biologic mechanism against this patient's extensive tunneling disease.

With two additional biologics now available for patients who fail first-line therapy, Dr. Tjahjono differentiates an IL-17A inhibitor from an IL-17A/F inhibitor, noting more IL-17-targeted agents are still in development. For patients with extensive tunneling like this one, he favors the dual A/F inhibitor, citing data showing tunnels express more IL-17F, though he stresses the A-only option remains a reasonable choice with flexibility to intensify dosing if response is inadequate. Panelists agree neither should be used as monotherapy; adjuncts like spironolactone or metformin for insulin resistance, and occasionally an off-label JAK inhibitor for especially high inflammatory burden, round out the regimen.

A panelist highlights that recent trial data on this dual inhibitor tracked not just lesion clearance but inhibition of new draining tunnel formation, framing that as direct evidence against anatomic spread, which she describes as inflammation either reaching new body regions or creating new fistulas within existing ones. That distinction prompts a detailed discussion of groin exams, since this patient has tunnels there. One panelist, passionate about comorbid inflammatory bowel disease, stresses examining the full perineal area for skin tags, deep fissures, and non-healing erosions that can signal metastatic Crohn's disease, which can mimic HS. She asks about bowel symptoms and, when suspicious, orders a fecal calprotectin test; an elevated result, while not diagnostic alone, warrants gastroenterology referral before starting an IL-17 inhibitor given its relationship to inflammatory bowel disease.

The panel closes on language, urging clinicians to use direct anatomic terms, scrotum, vulva, perianal, rather than euphemisms, arguing that normalized vocabulary reduces patient shame and reflects clinician confidence.

In "Building Clinician Confidence to Treat HS Early and Aggressively," the panel discusses what gives dermatologists and advanced practice providers the confidence to treat HS aggressively.