From the Guidelines
Pyoderma gangrenosum is a rare, ulcerative skin condition characterized by painful, necrotic lesions, typically treated with a combination of topical and systemic therapies [ 1 ].
Key Characteristics
- The condition often occurs on the shins and adjacent to stomas [ 1 ]
- Lesions are typically preceded by trauma through a phenomenon known as pathergy [ 1 ]
- Initially, pyoderma gangrenosum takes the form of single or multiple erythematous papules or pustules, but subsequent necrosis of the dermis leads to the development of deep excavating ulcerations [ 1 ]
Treatment Options
- Initial management often involves high-dose corticosteroids, such as prednisone 1-2 mg/kg/day, tapered over 6-12 weeks [ 1 ]
- Additional therapies may include cyclosporine 2-3 mg/kg/day, or infliximab 5 mg/kg at weeks 0,2, and 6, to modulate the immune response and promote wound healing [ 1 ]
- Topical agents like clobetasol 0.05% ointment applied twice daily may also be used [ 1 ]
Diagnosis
- Pyoderma gangrenosum is usually diagnosed clinically, based on the characteristic appearance of the lesions following exclusion of other possible skin diseases [ 1 ]
- A biopsy from the periphery of the lesion can help exclude other skin disorders, although findings in pyoderma gangrenosum are non-specific [ 1 ]
From the Research
Definition and Characteristics of Pyoderma Gangrenosum
- Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis characterized by painful, necrotic ulceration 2.
- It typically affects patients in the third to sixth decades of life, with almost equal incidence in men and women 2.
- PG occurs most frequently on the lower extremities, but can also occur on other parts of the body, including the head and neck 2, 3.
- Five clinical variants are currently recognized: classic, bullous, pustular, vegetative, and peristomal types 2.
Pathophysiology and Associated Conditions
- The pathophysiology of PG is not fully understood, but it is most commonly considered a disease in the spectrum of neutrophilic dermatoses 4.
- PG is often associated with underlying systemic diseases, including inflammatory bowel disease (IBD), such as ulcerative colitis and Crohn's disease 2, 5.
- Approximately 50% of patients with PG also have another disease associated with PG, with IBD being one of the most common associated conditions 2, 5.
Diagnosis and Differential Diagnosis
- PG is often a diagnosis of exclusion, as there are no specific laboratory or histopathologic findings to confirm the diagnosis 2.
- The diagnosis of PG is based on clinical signs and patient history, and is supported by biopsy 5.
- Mimickers of PG include infection, vascular insufficiency ulcers, systemic vasculitides, autoimmune disease, cancer, and exogenous tissue injury, among others 2.
Treatment and Management
- Successful management of PG typically requires multiple modalities to reduce inflammation and optimize wound healing, in addition to treatment of any underlying diseases 2.
- Systemic corticosteroids, such as prednisone, have been mainstays of systemic treatment for PG, although increasing evidence supports the use of biologic therapies, such as tumor necrosis factor-α inhibitors, for refractory cases of PG 2, 5.
- Other treatment options include immunosuppressive and immunomodulatory therapies, as well as wound care and topical treatments 5, 4.