Pyoderma gangrenosum misdiagnosis resulting in amputation: A review

Pyoderma Gangrenosum (PG) is a rare, ulcerative cutaneous disorder typically affecting the lower extremities. The clinical appearance of PG can mimic various cutaneous infections and neoplasms, leading to misdiagnosis and mistreatment including unnecessary surgical interventions such as debridements and even amputations. Diagnostic criteria exist, including characteristic clinical appearance and the exclusion of other diagnoses, however no definitive test exists to confirm the diagnosis of PG. We have sought to differentiate between the clinical characteristics of patients with PG and diseases that mimic PG resulting in amputation or were considered for amputation. We evaluated published cases where patients with PG were mistaken for other conditions resulting in impending (near miss) amputation or complete amputation. Fourteen cases of PG were found in which amputation was considered for treatment or erroneously underwent amputation. In six cases a total or partial amputation was erroneously performed, while in other eight patients, amputation was considered before the correct diagnosis of PG was made. PG was most commonly misdiagnosed as soft tissue infection (e.g. necrotizing fasciitis) in patients who were considered for or underwent amputation. Lesions appearing in atypical sites such as the hands and the genitalia were major predisposing factors for misdiagnosis. The identification of inflammatory comorbid conditions and the absence of positive microbiological cultures favor the diagnosis of PG. Finally, consulting dermatology in patients with ulcers that are refractory to treatment with antibiotics and/or debridement is indicated to confirm the diagnosis of PG, as a dermatology consult resulted in avoidance of amputation in all of cases reviewed. STUDY TYPE: Review Article LEVEL OF EVIDENCE: V - A review article of relevant published case reports as it relates to the diagnosis and management of pyoderma gangrenosum.