Background: Hidradenitis suppurativa (HS) and pyoderma gangrenosum (PG) are both rare inflammatory skin conditions that are associated with systemic inflammatory diseases. We performed a retrospective medical chart review of patients with an overlap of HS and PG.
Observations: We identified 11 cases of PG lesions presenting in patients with HS. Ten of the patients were women, and 9 were obese. All the patients developed HS lesions first, a median of 2.5 years (range, 0-15 years) preceding the appearance of PG lesions. All patients required multiple therapeutic agents because their diseases were often poorly responsive to standard therapies. Two patients received tumor necrosis factor inhibitors; 1 responded to treatment. One patient was treated with anakinra (interleukin-1 receptor antagonist) and had a 75% improvement of her lesions.
Conclusions: We have identified a group of patients who have an overlap of PG and HS. Pyoderma gangrenosum can appear at any point after the development of HS and often has a severe, refractory course. We propose that PG and HS may represent variant manifestations of cytokine dysregulation by the innate immune system with common etiology. New therapeutic agents are eagerly sought, and further investigation with regard to interleukin 1 blockade is warranted.