Rheumatology

Question 1

What is the most specific autoantibody for lupus nephritis?

Answer 1

• dsDNA.

- Nearly 100% of children with SLE are ANA positive, but 30% of children who are ANA positive are otherwise well.

Question 2

What autoantibody is associated with HSP?

Answer 2

• pANCA.

Question 3

In what illnesses is pANCA positive?

Answer 3

• Polyarteritis nodosa.
• Kawasaki disease.
• Churg-Strauss syndrome.
• SLE.
• IBD.
• CF.
• PSC.

Question 4

What illness is associated with positive cANCA?

Answer 4

• Granulomatosis and polyangiitis (Wegners)

Question 5

What test increases the specificity of ANCA antibodies in granulomatosis and polyangiitis?

Answer 5

• Anti-PR3 - present in the majority.

Question 6

What are symptoms of polyarteritis nodosa?

Answer 6

• Fever of unknown origin.
• Weight loss and severe abdominal pain.
• Skin purpura, oedema, linear erythema with painful palpable nodules along course of affected arteries.

Question 7

What is acute haemorrhagic oedema of infancy?

Answer 7

• Leukocytoclastic vasculitis.
• Children 4m-2y.
• Fever, oedema and large bruise like lesions.
• Combination of ecchymosis, purpura and petechiae with urticarial wheals.
• Trunk and mucous membranes spared.
• Ears can be involved with bleeding causing cauliflower ear.
• May be spectrum with HSP.