The diagnosis of pyoderma gangrenosum (PG) can be exceedingly difficult, and misdiagnosis can potentially yield serious consequences. Clinical criteria for establishing a reliable diagnosis have been previously proposed, but a consensus in their application has yet to be reached.

We sought to review recent trends in diagnosing PG and compare them with previously suggested diagnostic criteria.

Data for this article were obtained by searching the PubMed database using the key words “pyoderma gangrenosum.” Our search was limited to adult case reports that appeared in the English-language literature and received a final diagnosis of PG. The full text of the latest published 30 case reports that fulfilled these search criteria was reviewed. The articles spanned the years 2008 and 2009. Clinical features that appeared in the case descriptions were summarized and compared with the diagnostic criteria for the disease that were previously proposed.

Of the 30 case reports, 16 described ulcers involving one or both legs, whereas only one case had peristomal involvement. Although 8 cases were associated with inflammatory bowel disease, 11 of the 30 patients did not have a systemic comorbidity. Fifteen lesions were noted to manifest at sites of trauma, which ranged from surgical incision sites to prolonged seatbelt compression. Nine case reports mentioned an undermined border in their clinical description, whereas only 5 authors commented on pustules and 6 described a purulent discharge. Only two authors commented on cribriform scarring.

We only reviewed the latest published 30 case reports. Case series, which may have shown more typical cases, were excluded.

Currently, there is an underemphasis of clinical features in the diagnosis of PG, which can potentially lead to overdiagnosis. Establishing firm clinical criteria for diagnosing PG will ensure that case reports describe the same disease. This has implications in optimizing treatment strategies and improving patient outcomes.