1. Pyoderma gangrenosum

2. Primary Pyoderma gangrenosum

3. Diagnosis Criteria ? ? ? Patient still awaiting
biopsy results
Abela C.B., et.al. Pyoderma gangrenosum. British Journal of Oral and Maxillofacial Surgery. SW17 0QT, UK. Department of Plastic and Reconstructive Surgery, St George’s Hospital, Blackshaw Road, Tooting, London SW17 0QT, UK. 3 November 2005

4. Pyoderma gangrenosum
Inflammatory condition of skin characterized histologically by necrosis, ulceration and vasculitis
30-50 years old- most commonly affected
lesions most commonly found on the lower extremities and trunk
Its character is non infectious
No identifiable infective pathogen, unknown cause
Abela C.B., et.al. Pyoderma gangrenosum. British Journal of Oral and Maxillofacial Surgery. SW17 0QT, UK. Department of Plastic and Reconstructive Surgery, St George’s Hospital, Blackshaw Road, Tooting, London SW17 0QT, UK. 3 November 2005
Pyoderma gangrenosum: a review. A. Neil Crowson, Martin C. Mihm Jr., and Cynthia Magro, pp 98

5. *Mainly involves lower extremities
Pyoderma gangrenosum: Classification and management. Frank C. Powell, FRCPI, W. P. Daniel Su, MD, Harold O. Perry, MD . Dublin, Ireland, and Rochester, Minnesota

6. Pathophysiology poorly understood
In 50 to 70% of the patients, PG is associated with underlying systemic diseases such as inflammatory bowel disease, myeloproliferative disorders, hematological or malignancies
Involves dysregulation of immune system
there may be a neutrophil dysfunction causing metabolic oscillation and abnormal transit of neutrophils
Altered eosinophil chemotaxis may be involved
Pyoderma gangrenosum: a challenge to the rheumatologist. Luciano Ferreira Coelho, Francine Guilherme Correia, Fernanda Assis Ottoni, Flávia Patrícia Sena Teixeira Santos, Luciana Baptista Pereira, Cristina Costa Duarte Lanna

7. Pathophysiology
Direct immunofluorescence testing supports a vasculopathy as playing a role in lesional propagation in some patients by virtue of perivascular deposition of immunoreactants, mainly IgM, C3 and fibrin ;
CrowsonAN,Magro C, MihmMCJr.Py odermagangrenosum: a review. JCutan Pathol 2003; 30: 97^107.#BlackwellMunksgaard 2003. ;

8. Polypoid or bullous forms may rarely occur.
nodes or painful sterile pustules occur
central ulceration develops
Are deep and reach dermis and the subcutaneous tissue
classic ulcer is extensive, with infiltrated borders, erythematous-violaceous, undermined, with necrotic background and granulation tissue
Picture taken from medscape.com
NB:
Ulcers may be single or multiple, are more frequent in lower limbs and may be found in any other part of the body.
Almost 30% of the patients present previous trauma caused by a wound(pathergy).
Polypoid or bullous forms may rarely occur.
Pyoderma gangrenosum: a challenge to the rheumatologist. Luciano Ferreira Coelho, Francine Guilherme Correia, Fernanda Assis Ottoni, Flávia Patrícia Sena Teixeira Santos, Luciana Baptista Pereira, Cristina Costa Duarte Lanna

9. Histopathology
Skin biopsies of all forms of PG show a central zone of necrotizing suppurative inflammation. ;

10. Histopathology
And also a “Sweet-like” vascular reaction defined by peripheral neutrophilic component, usually without concomitant fibrinoid necrosis. ;