Rheumatology

Question 1

Which bottles/tubes should be used for joint arthrocentesis and why?

Answer 1

Plain sterile bottle- For M/C/S and gram stain, lower rate of false positives than blood culture bottles
FBE (EDTA) tube- At least 1ml, used for accurate cell count and differential

Question 2

What is seen in gout arthrocentesis microscopy?

Answer 2

Monosodium urate crystal (negative birefringence, needle shape, blue) these are located inside the phagocytes
High WCC’s
No bacteria

Question 3

What is seen in pseudogout arthrocentesis microscopy?

Answer 3

Calcium pyrophosphate crystals (positive birefringence, rhomboid, yellow)
High WCC’s
No bacteria

Question 4

When should nucleic acid amplication testing(NAAT)/PCR be considered on synovial fluid?

Answer 4

When there is a history suggestive of reactive arthritis ie recent diarrhoeal illness, recent STI

Question 5

What are the 3 most common causes of drug induced SLE

Answer 5

Isoniazid
Procainamide
Hydralazine (most common and highest rate of 5%)

Question 6

How is haemarthrosis generally managed?

Answer 6

• Aspirate for both analysis and symptom relief (if tense effusion)
• RICE
• Simple analgesia +/- opioids
• If using NSAID’s use “coxibs” as they are selective for COX-2 and thus dont inhibit platelet function and worsen bleeding
• Consider reversing coagulation
• Consider joint lavage in patients with recurrent bleeds from a coagulopathy

Question 7

What are the causes of haemarthrosis?

Answer 7

• Trauma
• Post operative
• Anticoagulation
• Bleeding disorder (ie haemophilia)
• Charcots joint (neuropathy)
• secondary to septic arthritis
• Tumours
• AVM

Question 8

What are the differentials for Oligoarthritis?

Answer 8

• Rheumatic fever
• Oligoseptic arthritis (15%)
• Reiters (reactive arthritis)
• Gonococcal arhritis
• Viral poly(aseptic)arhritis
• Autoimmune disorders (ie RA)
• Syphilis
• Melioidosis

Question 9

What are the clinical features and confirmatory test for Behcets disease?

Answer 9

• Oral ulceration
• Asymmetric polyarthritis
• Anterior uveitis
• Pathergy test

Question 10

What are the treatments for Raynauds Phenomenon?

Answer 10

Acute
- Rewarming in warm water
- nifedipine 10mg IR TDS
- If severe heparin infusions, nerve blocks, prostaglandin infusions

Prophylaxis
- Diltiazem, nifedipine, prazosin

Question 11

What are the two best tests for Rheumatoid arthritis?

Answer 11

RF and Anti-CCP
- When combined specificity reaches 100%

Question 12

What is the difference between ertyhema multiforme major and minor?

Answer 12

Major has mucous membrane involvement but minor doesnt

Question 13

How is Peroneal nerve injury differentiated from LF radiculopathy?

Answer 13

pEronEal Nerve
- Weakness on foot “E”version

L5 Radiculopathy
- Weakness on foot Inversion

Question 14

What is the typical cause of Reiters Syndrome?

Answer 14

Reactive Arthritis
- Oligoarthritis, back pain (spondyloarthritis), dactylitis (sausage digitis) and enthesitis
- Most commonly affected joint is the knee
- Caused by enteric bacteria (ie salmonella) and Chlamydia