dermatologic disorders
Pyoderma Gangrenosum
Symptoms and Signs of Pyoderma Gangrenosum
Most often, pyoderma gangrenosum begins as an inflamed erythematous papule, pustule, or nodule. The lesion, which may resemble a furuncle or an arthropod bite at this stage, ulcerates and expands rapidly, developing a swollen necrotic base and a raised dusky to violaceous border. An undermined border (ie, loss of underlying support tissue at the border) is common, if not pathognomonic. Systemic symptoms such as fever and malaise are common. The ulcers can coalesce to form larger ulcers, often with cribriform or sieve-like scarring. Symptoms and signs can vary with the subtype. In this most common subtype, ulcers form as described above, most commonly on the lower extremities or trunk, particularly the buttocks and perineum. This less common subtype often develops in patients with hematologic disorders. Lesions usually begin as bullae that erode, becoming superficial ulcers. The arms and face are most often involved. This subtype tends to develop during exacerbations of inflammatory bowel disease. Painful pustules develop, surrounded by erythema. Arthralgias are common. In this subtype, a single, indolent, mildly painful plaque or superficial ulcer develops, most often on the head or neck. The border is not undermined and the base is not necrotic. Pyoderma gangrenosum can also develop at other sites, such as around a stoma in patients who have inflammatory bowel disease (peristomal pyoderma gangrenosum), on the genitals (genital pyoderma gangrenosum), or in sites other than the skin, such as the bones, cornea, central nervous system, heart, intestine, liver, lungs, or muscle (extracutaneous pyoderma gangrenosum). 