pyoderma gangrenosum

Question 1

pyoderma gangrenosum is classified as ?

Answer 1

neutrophilic dermatosis - characterised by dense infiltration of neutrophils in the affected tissue and this is often seen on biopsy

Question 2

x

Question 3

cause of pyoderma gangrenosum?

Answer 3

Causes :
idiopathic in 50%

inflammatory bowel disease :
ulcerative colitis
Crohn’s

rheumatological :
rheumatoid arthritis
SLE

haematological :
myeloproliferative disorders
lymphoma
myeloid leukaemias
monoclonal gammopathy (IgA)

granulomatosis with polyangiitis

primary biliary cirrhosis

Question 4

features of pyoderma gangrenosum ?

Answer 4

=location
typically on the lower limb
soften at the site of a minor injury as in this patient’s case and this is known as pathergy

initially features:
usually starts quite suddenly
small pustule, red bump or blood-blister

=later features:
the skin then breaks down resulting in an ulcer which is often painful
the edge of the ulcer is often described as purple, violaceous and undermined.

the ulcer itself may be deep and necrotic
may be accompanied by systemic symptoms

fever
myalgia

Question 5

pyoderma gangrenosum ?

Answer 5

histology results and when other diseases have been ruled out

histology is not specific and can vary depending on the time and site of the specimen but may be helpful in ruling out other causes of an ulcer.

Question 6

Mx pyoderma gangrenosum ?

Answer 6

oral steroids as first-line treatment

other immunosuppressive therapy - ciclosporin and infliximab,

any surgery should be postponed until the disease process is controlled on immunosuppression to risk worsening of the disease (pathergy)