Rheumatology

Question 1

HLA B27 associations

Answer 1

Ankylosing spondylitis
Reactive arthritis
Acute anterior uveitis

Question 2

HLA A3 associations

Answer 2

Haemochromatosis

Question 3

HLA-B51 associations

Answer 3

Behcet’s disease

Question 4

HLA-DQ2/DQ8 Associations

Answer 4

coeliac disease

Question 5

HLA-DR2 associations

Answer 5

narcolepsy

Goodpasture’s

Question 6

HLA-DR3 associations

Answer 6

dermatitis herpetiformis
Sjogren's syndrome
primary biliary cirrhosis
Hashimotos
Early onset Myasthenia

Question 7

HLA-DR4 associations

Answer 7

type 1 diabetes mellitus*

rheumatoid arthritis - in particular the DRB1 gene (DRB104:01 and DRB104:04 hence the association with DR4)

Question 8

Anti -Ro

Answer 8

SLE–> HB

Sjogrens

Question 9

Anti-La

Answer 9

Sjogrens

Question 10

anti Jo

Answer 10

Polymyositis and dermatomyositis

more common by far in polymyositis

Question 11

anti scl-70

Answer 11

diffuse cutaneous systemic sclerosis

scleroderma

Question 12

anti centromere

Answer 12

limited cutaneous systemic sclerosis

Question 13

anti Mi-2

Answer 13

most sensitive for dermatomyositis

Question 14

anti SMA

Answer 14

autoimmune hepatitis

Question 15

anti -histone

Answer 15

drug induced lupus

Question 16

C-ANCA

Answer 16

GPA–>PR3

Question 17

ANA

Answer 17

most common in dermatomyositis
100% of drug induced lupus -dsDNA-ve
SLE

Question 18

anti-CCP

Answer 18

RA- most specific

Question 19

RF

Answer 19

RA most sensitive

Felty's syndrome (around 100%)
Sjogren's syndrome (around 50%)
infective endocarditis (around 50%)
SLE (= 20-30%)
systemic sclerosis (= 30%)
general population (= 5%)
rarely: TB, HBV, EBV, leprosy

Question 20

anti-RNP

Answer 20

mixed connective tissue disease

Question 21

pANCA

Answer 21

eGPA–> myeloperoxidase

Question 22

anti-smith

Answer 22

drug induced lupus

Question 23

Methotrexate MOA

Answer 23

antimetabolite that inhibits dihydrofolate reductase, an enzyme essential for the synthesis of purines and pyrimidines.

Question 24

Methotrexate adverse effects

Answer 24

mucositis
myelosuppression
pneumonitis
pulmonary fibrosis
liver fibrosis

Question 25

methotrexate monitoring

Answer 25

methotrexate is taken weekly, rather than daily FBC, U&E and LFTs need to be regularly monitored. The Committee on Safety of Medicines recommend 'FBC and renal and LFTs before starting treatment and repeated weekly until therapy stabilised, thereafter patients should be monitored every 2-3 months' folic acid 5mg once weekly should be co-prescribed, taken more than 24 hours after methotrexate dose

Question 26

methotrexate interactions

Answer 26

avoid prescribing trimethoprim or co-trimoxazole concurrently - increases risk of marrow aplasia high-dose aspirin increases the risk of methotrexate toxicity secondary to reduced excretion

Question 27

methotrexate toxicity management

Answer 27

folinic acid

Question 28

MOA Denosumab

Answer 28

monoclonal antibody. It prevents the development of osteoclasts by inhibiting RANKL. Osteoclasts break down bone, and therefore by preventing their development, bone loss is reduced.

Question 29

septic arthritis antibiotic

Answer 29

flucloxacillin | clindamycin if penicillin allergic

Question 30

Polyarteritis nodosa features

Answer 30

vasculitis affecting medium-sized arteries with necrotizing inflammation leading to aneurysm formation fever, malaise, arthralgia weight loss hypertension *mononeuritis multiplex* , sensorimotor polyneuropathy testicular pain livedo reticularis haematuria, renal failure perinuclear-antineutrophil cytoplasmic antibodies (ANCA) are found in around 20% of patients with 'classic' PAN hepatitis B serology positive in 30% of patients

Question 31

SLE autoantibodies

Answer 31

99% are ANA positive this high sensitivity makes it a useful rule out test, but it has low specificity 20% are rheumatoid factor positive anti-dsDNA: highly specific (> 99%), but less sensitive (70%) anti-Smith: highly specific (> 99%), sensitivity (30%) also: anti-U1 RNP, SS-A (anti-Ro) and SS-B (anti-La) Anti-Ro antibodies are present in 15% of patients with SLE, but are more frequently associated with Sjörgren's syndrome.

Question 32

dermatomyositis malignancy

Answer 32

(typically ovarian, breast and lung cancer, found in 20-25% - more if patient older). Screening for an underlying malignancy is usually performed following a diagnosis of dermatomyositis

Question 33

antiphospholipid features

Answer 33

venous/arterial thrombosis recurrent fetal loss livedo reticularis thrombocytopenia prolonged APTT (due to an ex-vivo reaction of the lupus anticoagulant autoantibodies with phospholipids involved in the coagulation cascade) other features: pre-eclampsia, pulmonary hypertension