Dual-Site Postsurgical Pyoderma Gangrenosum of the Breast and Back With Delayed Diagnosis: A Case Report

BACKGROUND Postsurgical pyoderma gangrenosum is a rare neutrophilic dermatosis that can mimic infection, wound dehiscence, malignancy, foreign-body reaction, or impaired surgical healing. Diagnostic delay is common and may lead to repeated debridement, which can worsen ulceration through pathergy. This case highlights the diagnostic challenge of multifocal postsurgical pyoderma gangrenosum involving anatomically distinct sites after procedures initially performed for presumed benign lesions. CASE REPORT A 70-year-old woman with celiac disease and prior left breast cancer treated with lumpectomy, chemotherapy, radiation, and implant reconstruction developed nonhealing ulcers of the left superior breast and left lower back after surgical treatment of benign lesions. Initial evaluation favored retained cyst lining, foreign-body reaction, infection, impaired wound healing, and possible implant-related complications. Despite advanced wound therapies, antimicrobials, and biologic wound products, both lesions progressively enlarged. Biopsies demonstrated abscess formation, multinucleated giant cells, and sinus tract formation without malignancy. Wound cultures and pulmonary findings complicated the diagnostic course, but neither targeted antimicrobial nor prolonged antifungal therapy produced sustained improvement. The diagnosis was clinically supported by worsening after procedural intervention, exclusion of malignancy and persistent infection, multifocal involvement, and rapid response after initiation of topical and intralesional corticosteroid therapy. CONCLUSIONS This case supports considering postsurgical pyoderma gangrenosum in refractory postsurgical wounds that worsen despite local wound-directed interventions, particularly when lesions involve multiple anatomically distinct surgical sites. The complete resolution of both lesions after topical and intralesional corticosteroid therapy further supports the importance of recognizing an inflammatory, pathergy-driven process once infection, malignancy, and other local causes have been reasonably excluded. Earlier recognition may help avoid repeated procedural trauma, unnecessary treatment escalation, and prolonged morbidity.