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 PGin 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.