Risk of Developing Pyoderma Gangrenosum after Procedures in Patients with a Known History of Pyoderma Gangrenosum – A Retrospective Analysis

Background The risk of postoperative pyoderma gangrenosum (PG) in patients with a known history of PG is unknown. Objective To quantify risk and identify patient- and/or procedure-related risk factors for postsurgical recurrence or exacerbation of PG in patients with a known history of PG. Methods We retrospectively evaluated the likelihood of postsurgical recurrence or exacerbation of PG for all patients with a confirmed diagnosis of PG at Brigham and Women's Hospital and Massachusetts General Hospital from 2000 to 2015. Results In all, 5.5% of procedures (n = 33) led to recurrence of PG in 15.1% of patients (n = 25). Compared with skin biopsy, small open surgical procedures had an adjusted odds ratio (aOR) of 8.65 (95% confidence interval [CI], 1.55-48.33) for PG recurrence or exacerbation; large open surgical procedures had an aOR of 5.97 (95% CI, 1.70-21.00); and Mohs micrographic surgery/skin excision had an aOR of 6.47 (95% CI, 1.77-23.61). PG chronically present at the time of the procedure had an aOR of 4.58 (95% CI, 1.72-12.22). Immunosuppression, time elapsed since the original PG diagnosis, and procedure location did not significantly influence risk. Limitations Our study is limited by its retrospective nature and relatively small sample size. Conclusion There is a small but clinically meaningful risk for postsurgical recurrence or exacerbation of PG in patients with a known history of PG; higher risks occur with more invasive procedures and chronically present PG.