Immunology 9 - Hypersensitivity disorders (Path Guide)

Question 1

Against what are antibodies directed in HDN?

Answer 1

Rhesus antigens on neonatal erythrocytes

Question 2

Against what are antibodies directed in autoimmune haemolytic anaemia?

Answer 2

Rh blood group antigens

Question 3

Against what are antibodies directed in ITP?

Answer 3

Glycoprotein IIb/IIIa on platelets

Question 4

Against what are antibodies directed in pemphigus vulgaris?

Answer 4

Epidermal cadherin/desmoglein 1 and 3

Question 5

Against what are antibodies directed in acute rheumatic fever?

Answer 5

M proteins on GAS

Question 6

What tests can be used to diagnosis myasthenia gravis?

Answer 6

Anti nAch-R Ab
Abnormal EMG
Tensilon test

Question 7

How is the tensilon test performed?

Answer 7

Injection of reversible acetylcholine esterase inhibitor

Patient with MG will experience increased strength and endurance with repetitive movements

Question 8

Recall some treatments for myasthenia gravis

Answer 8

Neostigmine

Pyridostigmine

Question 9

How should eosinophilic granulomatosis with polyangiitis be treated?

Answer 9

pANCA- anti myeloperoxidase

Corticosteroids
Cyclophosphamide
Azathioprine (Instead of co-trimax which is used in granulomatosis with polyangitis)

Question 10

How should granulomatosis with polyangiitis be treated?

Answer 10

(C)-ANCA: proteinase (3)

3Cs
Corticosteroids
Cyclophosphamide
Co-trimoxazole

Question 11

Livedo reticularis is seen in which of the vasculitides?

Answer 11

Microscopic polyangiitis

Question 12

Against what are antibodies directed in mixed essential cryoglobulinaemia?

Answer 12

IgG +/- HepC antigens

Question 13

Recall the symptoms of mixed essential cryoglobulinaemia

Answer 13

S- Skin changes (maculopapular non blanching lesions)
K- Kidney involvement- Membranous proliferative glomerulonephritis
I- Intra-articular (arthralgia)
N- Nerve involvement

Association with Hep C
C4 titres will be low due to complement activation
Type3 hypersensitivity

Question 14

Recall the symptoms of serum sickness

Answer 14

Rashes, pruritis, arthralgia, lymphadenopathy, fever and malaise, 7-12 days following exposure to penicillin

Question 15

How can serum sickness be diagnosed?

Answer 15

Decreased C3

Blood shows immune complexes or signs of blood vessel inflammation

Question 16

Which antigens are involved in polyarteritis nodosa?

Answer 16

Hep B + C viral antigens

Question 17

In what type III hypersensitivity disorder might the ‘rosary sign’ be seen, and what is this sign?

Answer 17

Polyarteritis nodosa

CT finding showing adenomyosis of the gallbladder - similar to pearl necklace sign

Question 18

Recall the symptoms/signs of SLE

Answer 18

ARMADA SHIPS
Arthritis
Raynaud's/ renal findings
Malar rash
ANA positive
Discoid rash
Apthous ulcers

Serositis
Haematology findings
Immunology (anti-dsDNA, anti-sm)
Photosensitivity
Seizures

C4 reduced, C4 and C3 reduced in severe disease

Question 19

Recall some drugs that can cause drug-induced SLE

Answer 19

Hydralyzine (anti-hypertensive. Class: vasodilators, MOA: inhibits vascular production of Reactive Oxidative Species)
Isoniazid (TB-inhibits formation of mycobacterial cell wall)
Procainamide (anti-arrhythmic drug-inhibits sodium channels)

Question 20

What is the defininitive diagnostic test for MS?

Answer 20

LP –> CSF showing oligoclonal bands of IgG on electrophoresis

Question 21

Recall the uses of different cytokine therapies

IFNa:
IFNb:
IFNgamma:
IL-2L

Answer 21

- IFNa
	o Hairy cell leukaemia
	o CML
	o Multiple myeloma
	o Used as an adjunct for: HBV, HCV, Kaposi sarcoma
- IFNb- Behcet’s, relapsing MS
- IFNgamma- Stimulates phagocytes in patients with Chronic granulomatous disease
- IL-2- Used in Renal cell cancer

Question 22

Recall the antibodies involved in Sjogren’s syndrome

Answer 22

Anti-Ro

Anti-La

Question 23

Recall the antibodies involved in polymyositis/ dermatomyositis

Answer 23

Anti-Jo-1

Question 24

What are the HLA associations of coeliac?

Answer 24

HLA-DQ2 and DQ8 (two eight or not to eat?)

Question 25

Recall the antibodies involved in autoimmune hepatitis

Answer 25

Anti-smooth muscle
Anti-LKM-1
Anti soluble liver antigen (anti-SLA)

Question 26

What is anti-U1RNP (speckled pattern) associated with?

Answer 26

Mixed connective tissue disease (including SLE)

Question 27

What antibody is involved in primary biliary cirrhosis?

Answer 27

Anti-mitochondrial