The 5 P's of Pyoderma Gangrenosum

December 2019 | Volume 18 | Issue 12 | Features | 1282 | Copyright © December 2019

Brett C. Neill MD,ª Edward W. Seger MS,ª Tyler A. Hooton BS,ª Gabrielle Bailey BS,ª Anand Rajpara MD,ªWilliam V. Stoecker MD MSb

ªDivision of Dermatology, University of Kansas Medical Center, Kansas City, KS 

BDepartment of Dermatology, University of Missouri, Columbia, MO 

*This work won First Place in the 9th Annual ARTE Poster Competition at ODAC.

Due to the complex nature of PG diagnosis, we postulate that this simple mnemonic will have the most utility with nondermatology clinicians encountering a lesion suspicious for PG. By assisting in differential diagnosis formation, this mnemonic may lead to timelier biopsies and treatment initiation. At that time, the utilization of the more precise criteria set forth by Jockenhöfer et al will allow for the dermatologist to more definitively establish a diagnosis of PG.4 The limitations of this concept mirror those of other studies and include lower sensitivities in patients with an atypical PG presentation. In addition, by omitting some histopathologic and treatment response criteria in the proposed mnemonic, the specificity, inadvertently, will be reduced. However, most of the omitted criteria are not available on initial evaluation. Despite these limitations, we believe this is a useful approach with simplicity that facilitates adoption into clinical practice.


The 5 P’s of PG offers a useful mnemonic for the diagnosis of PG, particularly in the initial clinical diagnosis prior to skin biopsy and treatment.


No author has conflicts of interest relevant to the manuscript. There are no funding sources to disclose.



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Brett C. Neill MD