Rheumatology

Question 1

DDx monoarthritis

Answer 1

Articular - gout, pseudogout, septic arthritis (rule out gonorrhoea), synovitis, trauma
Peri articular - ligament injury, tendonitis, bursitis, cellulitis
Non-articular - cellulitis, osteomyelitis

Question 2

Precipitants of pseudogout (diseases)

Answer 2

Osteoarthritis

Haemachromatosis

Question 3

Precipitants of gout

Answer 3

Surgery
dehydration
fasting 
binge eating
heavy alcohol ingestion
trauma
cold weather

Question 4

Reactive arthritis symptoms

Answer 4

Reiter’s syndrome - iritis, urethritis, arthritis

Question 5

Secondary causes of gout

Answer 5

1. Decreased urate clearance e.g. CKD
2. Increased cell turnover (malignancy, myeloproliferative e.g. Polycythemia vera, primary myelofibrosis, essential thrombocytosis)

Question 6

Gout crystal on synovial aspirate

Answer 6

needle-shape crystals

negatively birefringents

Question 7

Target uric acid levels

Answer 7

360umol/L and 300umol/L for tophaceous gout

Question 8

Indications for chronic urate lowering therapy

Answer 8

Tophaceous gout
Recurrent attacks ≥2/year
Stage 2 ckd or worse
Hx of renal stones

Question 9

Haemolytic screen

Answer 9

FBC - reduced haemoglobin
Blood film - assessing for schistocytes, keratocytes, or other poikilocytes
LFT - unconjugated hyperbilirubinaemia
LDH - elevated
Haptoglobin 0 reduced, particularly in intravascular haemolysis
Reticulocytes - elevated in haemolysis
Direct antiglobulin test (DAT) - positive in immune haemolysis

Question 10

Differentials for febrile acute transfusion reaction

Answer 10

Febrile non-haemolytic transfusion reaction (FNHTR) (mild/severe) (more common with plasma-rich blood products FFP or CSP/pooled platelets)

Transfusion transmitted bacterial infection (TTBI) (more common after transfusion of platelets than red cells)

Acute haemolytic transfusion reaction (AHTR)

• transfusion of ABO-incompatible red cells
• react with patient’s anti-A or anti-B antibodies
• Complement activation –> destruction of transfusion RBC –> release of cytokines –> shock –> AKI
• chills, rigors, hypotension/shock, tachycardia, dyspnoea, DIC, haemoglobinuria