Figure 1. Right foot at initial presentation in the emergency department.
Figure 2. Image of left foot 2 days after admission.
A 66-year-old woman presents to the emergency department (ED) with a 5-day history of spontaneous wounds appearing on both of her feet and ankles. The wounds are increasingly painful and are ulcerating rapidly. The ulceration on the left foot is the largest and most painful. She is admitted to the hospital where she develops fever and skin necrosis on the left foot despite being given broad-spectrum intravenous antibiotics. A photograph of the right foot at initial presentation in the ED and an image of the left foot 2 days after admission are shown in Figures 1 and 2. The medical team suspects pyoderma gangrenosum.
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Pyoderma gangrenosum (PG) is a rare noninfectious painful inflammatory skin disease characterized by an initial area of erythema or pustule followed by progressive wound ulceration. The ulceration can progress rapidly with a raised inflammatory border, necrotic base, and purulent discharge. The most common location of PG is the lower extremity but any part of the body can be affected. The ulceration may become malodorous due to secondary infection.1-3
The cause of PG is thought to be autoimmune. In 50% of patients, PG is associated with an underlying disease such as inflammatory bowel disease, paraproteinemia, arthritis, and myeloproliferative disorders; the other 50% of cases are idiopathic.1 The diagnosis of PG is primarily made by clinical features and supported by biopsy; histopathology is often not specific.3 Neutrophilic proliferation is often seen in tissue samples. Skin biopsy should be performed to rule out other causes of ulceration including infection, vasculitis, and malignancy.1-3
The clinical course of PG varies greatly, is unpredictable, and can be mild or malignant. Lesions can heal and not reoccur, last for years, or heal and return months to years later. Severe cases can progress to where surgical debridement, skin grafts, and even limb amputation may be necessary.2,3
Systemic corticosteroids are the initial treatment of choice to halt progression of ulceration. Other immunosuppressive agents may be used along with antibiotics to treat secondary infection. Wound management is a critical part of treatment with wet to dry dressings and frequent wound checks.2,3
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor in chief of the Journal of Orthopaedics for Physician Assistants.
1. Besure SV, Tadakamalla A, Talluri SK. Pyoderma gangrenosum. QJM. 2012;105(12):1219-20. doi:10.1093/qjmed/hcr198
2. Callen JP. Pyoderma gangrenosum. Lancet. 1998;351(9102):581-585. doi:10.1016/S0140-6736(97)10187-8
3. Wollina U. Pyoderma gangrenosum — a review. Orphanet J Rare Dis. 2007;2:19. doi:10.1186/1750-1172-2-19