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pyoderma gangrenosum

Wednesday 11 February 2004

Definition: Pyoderma gangrenosum (PG) is an uncommon, chronic ulcerative condition of the skin that was first described in 1930. It can occur in any age group, but only 4% of the patients are infants or children. An underlying systemic disease is present in approximately 50% of the patients with PG.

The most common associations include inflammatory bowel disease, arthritis, lymphoproliferative disorders and chronic recurrent multifocal osteomyelitis (CRMO).

Pyoderma gangrenosum (PG) is a rare noninfectious neutrophilic dermatosis. Clinically it starts with sterile pustules that rapidly progress and turn into painful ulcers of variable depth and size with undermined violaceous borders.

The legs are most commonly affected but other parts of the skin and mucous membranes may also be involved. Course can be mild or malignant, chronic or relapsing with remarkable morbidity.




- cutaneous pyoderma gangrenosum
- oral pyoderma gangrenosum


- inflammatory bowel diseases (IBDs)

  • Crohn disease
  • ulcerative colitis

- arthritis
- lymphoproliferative disorders
- chronic recurrent multifocal osteomyelitis (CRMO)


- Wollina U. Pyoderma gangrenosum. Orphanet J Rare Dis. 2007 Apr 15;2:19. PMID: 17433111