Pyoderma Gangrenosum

1. See Also
   1. Pathergy
2. Epidemiology
   1. Rare
3. Pathophysiology
   1. Neutrophilic dermatosis
      1. Also occurs in Behcet Disease and Sweet Syndrome
      2. Neutrophils release elastase and other enzymes that result in skin breakdown
4. Symptoms
   1. Painful Pustules and ulcers that form on the legs, buttocks, Abdomen and face in response to minor Skin Trauma
5. Signs
   1. Lesion characteristics
      1. Initial
         1. Hemorrhagic, red Pustule or painful, tender Nodule
      2. Next
         1. Lesion ulcerates
         2. Ulcer has irregular, raised, undermined border and advances peripherally
         3. Ulcer base with exudate that is pustular and hemorrhagic
         4. Necrotic eschar may form
      3. Next
         1. Ulcer heals with thin, atrophic scar
   2. Distribution (in order of most common to least common)
      1. Legs
      2. Buttocks
      3. Abdomen
      4. Face
   3. Pathergy
      1. See Pathergy Test
      2. Blistering and ulceration in response to minor Trauma
      3. Also seen with Behcet Disease
6. Associated Conditions
   1. Inflammatory Bowel Disease (e.g. Crohn's Disease, Ulcerative Colitis)
   2. Arthritis
   3. Hematologic Malignancy (e.g. Multiple Myeloma, Leukemia)
   4. Hepatitis
7. Differential Diagnosis
   1. See Skin Ulcer
8. References
   1. Fitzpatrick (1992) Color Atlas and Synopsis of Clinical Dermatology
   2. Jhun and DeClerck in Herbert (2015) EM:Rap 15(8): 19-20
   3. Heiner (2015) Ann Emerg Med 66(2):115-8 [PubMed]