Pyoderma Gangrenosum

Presentation :

• Rare
• Most commonly presents w/ inflammatory papule or pustule that progresses to a painful ulcer with a violaceous undermined border and a purulent base.
  • Lesion development is often rapid and the level of pain is often greater than expected based upon the appearance of the ulcer
  • 
• Often associated with an underlying autoimmune disease (IBD, RA, Ankylosing Spondylitis), heme malignancies, and heme diseases (MGUS, MDS, Polycythemia vera), post-surgical

Pathophysiology :

• Inflammatory neutrophilic dermatosis

Diagnostic Testing:

• Diagnosis of exclusion
• Biopsy is required, will require derm consultation
  • Optimal is an elliptical incisional biopsy w/ inflamed lesion border + ulcer edge extending vertically into SubQ fat
• 1 major and 4 minor criteria for diagnosis:

Treatment :

• Limited disease = single or few small (<3 cm), superficial ulcers:
  • High potency corticosteroid cream
  • If insufficient can switch to topical tacro OR add oral minocycline/dapsone
  • Proceed to treatment for extensive disease
• Extensive disease:
  • Start w/ Oral Prednisone
  • Oral cyclosporine if prednisone is contraindicated
  • Add infliximab, adalimumab, or mycophenolate mofetil if treatment failure; some derm will use this at time of oral therapy initiation for a few weeks as well

Prognosis:

• 50% achieve wound healing within one year, and almost all patients achieve remission with more prolonged treatment.

• Relapses can occur after long periods of disease remission

References:

• https://dermnetnz.org/topics/pyoderma-gangrenosum
• https://www.uptodate.com/contents/pyoderma-gangrenosum-pathogenesis-clinical-features-and-diagnosis
• https://www.uptodate.com/contents/pyoderma-gangrenosum-treatment-and-prognosis