Diagnosis: Pyoderma gangrenosum
Pyoderma gangrenosum is a rare, ulcerative, neutrophilic dermatosis of uncertain etiology. It occurs in 1 in 100,000 people in the US per year.1 Fifty percent of patients with pyoderma gangrenosum have an underlying disorder such as inflammatory bowel disease, arthritis, hematological malignancy, infections, sarcoidosis, hypogammaglobulinemia, or HIV.2 Pyoderma gangrenosum occurs in 2% of patients with Crohn’s disease.9
Variants of pyoderma gangrenosum
The 2 primary variants are classical and atypical. Four types of lesions are seen.2
Ulcerative. Ulcerative pyoderma gangrenosum a classical form of disease and occurs usually in lower limb and trunk. Lesions begin as pustules or as a pathergic phenomenon (development of ulcer at site of minimal trauma). This progresses to a large violaceous ulcer with undermined borders and surrounding halo of erythema. The lesions are distinctively painful.
Pyoderma gangrenosum may occur on the genitalia and would need to be differentiated from sexually transmitted disease. Extracutaneous sterile neutrophilic abscesses have been reported in lungs, eyes, liver, spleen, bones, heart, central nervous system, and gastrointestinal tract.
Pustular. Present as painful postulations on extensor surfaces of the limbs. Pyostomatitis vegetans is a variant of this form and occurs in the oral cavity.
Bullous/atypical. Bullae most often occur on hands, forearm, or face. Most commonly associated with hematological malignancy.
Vegetative. Chronic, nonpainful superficial ulcer.
Treatment: Topical vs systemic
To date there are no established guidelines for treatment of pyoderma gangrenosum. Treatment of underlying disease often results in improvement of pyoderma gangrenosum.
Treat localized cases topically
Localized pyoderma gangrenosum may initially be treated with corticosteroids (topical or intralesional) or tacrolimus (SOR: B),7 reserving systemic treatment for refractory cases.
Topical care of the lesions along with systemic therapy should be limited to antiseptic or occlusive wound dressing in an effort to minimize secondary bacterial infection.
Surgery not recommended in active disease
Adjuvant surgery such as excision of ulcer, skin grafting, etc, has not been shown to reduce morbidity even when done in conjunction with systemic immunosuppressive therapy. Re-epithelialization procedures like debridements or allografts may be done during disease remission (SOR: C).7