A40-45 A Hole Lot More Than Skin: Cavitary Lung Lesions in Pyoderma Gangrenosum

Abstract Introduction The following abstract will summarize a case of pulmonary manifestations of pyoderma gangrenosum (PG) in a patient with hidradenitis suppurativa and ongoing tobacco use, integrating clinical history, infectious work-up, and imaging findings. The evidence highlights that pulmonary involvement in PG is rare but well-documented, often presenting as sterile neutrophilic infiltrates, nodules, or cavitary lesions, and is frequently misdiagnosed as infection or malignancy. Treatment typically involves immunosuppression with corticosteroids, cyclosporine, and/or TNF-α inhibitors. Case Report: A 50-year-old female patient with a history of hidradenitis suppurativa and ongoing tobacco use was diagnosed with pyoderma gangrenosum (PG) in 2015 via biopsy of a chronic lower extremity ulcer. Initial management included infliximab every 8 weeks with clinical improvement, and her dermatologic disease was ultimately controlled on a stable dose of infliximab every 6 weeks until she was lost to follow-up. After 3 months off systemic immunosuppression, the patient developed new pulmonary symptoms in addition to worsening skin ulceration. Chest imaging revealed a left upper lobe pulmonary cavitary lesion with surrounding patchy infiltrates. Infectious work-up, including bronchoalveolar lavage (BAL) and cultures for bacteria, fungi, and mycobacteria, was negative. Cell count and differential of BAL fluid was neutrophil-predominant. She was treated empirically with a prolonged course of amoxicillin/clavulanate in addition to re-initiation of her infliximab. Serial imaging of the cavitary lesion and regular dermatologic examinations demonstrated improvement of both the pulmonary and skin lesions. She was maintained on infliximab for about three years until an attempted taper was trialed. After 3 months off therapy, she had recrudescence of both the pulmonary cavitation and lower extremity ulceration, prompting re-initiation of infliximab with subsequent clinical and radiographic improvement (Figure 1). Discussion Pulmonary involvement in PG is rare, with fewer than 30 cases reported, and may present as nodules, cavitary lesions, or tracheobronchial disease. The pathogenesis is thought to involve dysregulated neutrophilic inflammation, with extracutaneous manifestations most commonly affecting the lung. Immunosuppressive therapy remains the mainstay of treatment, with biologics increasingly used in refractory cases. In this case, resumption of immunosuppression led to improvement in both cutaneous and pulmonary manifestations. This case underscores the importance of considering PG in the differential diagnosis of sterile pulmonary nodules or cavitary lesions, especially in patients with known neutrophilic dermatoses. Early recognition and appropriate immunosuppressive therapy are critical for optimal outcomes. This abstract is funded by: None