Rheumatology - mx

Question 1

GCA mx

Answer 1

Suspected GCA
• High dose oral prednisolone (treatment should not be delayed while awaiting biopsy)
• Visual/neurological symptoms/signs -Methylprednisolone pulse therapy followed by standard oral prednisolone

Confirmed GCA
• High dose oral prednisolone 40mg (+ PPI)
• Aspirin 75mg
• Osteoporosis prevention (alendronic acid/risedronate sodium + calcium carbonate + ergocalciferol) [bisphosphonates are given with calcium + vitamin D supplements]

Recurrent/relapsing disease or severe glucocorticoid adverse effects
• Tocilizumab (therapeutic + corticosteroid-sparing) • • Methotrexate

Question 2

Polymyalgia rheumatica mx

Answer 2

• Low-dose prednisolone 15mg OD for 1-2 years

• Osteoporosis prevention (alendronic acid/risedronate sodium + calcium carbonate + ergocalciferol) [bisphosphonates are given with calcium + vitamin D supplements]
o If corticosteroids >1m - corticosteroid-induced osteoporosis
o Bisphosphonate if DEXA scan shows a T score of 1.5 or lower

• Methotrexate/Azathioprine (+folic acid)
o Add on to prednisolone to decrease steroid dose needed
o If adverse corticosteroid effects
o Used as a corticosteroid-sparing agent, it should be continued until the corticosteroids can be tapered without the recurrence of PMR symptoms
o The folic acid should be given everyday other than the day methotrexate is taken, given to prevent BM suppression

Question 3

Side effects of methotrexate

Answer 3

• Myelosuppression
Leucopenia, agranulocytosis, thrombocytopenia, anaemia
Pt should report immediately any signs (e.g. sore throat, bruising, SOB, abdominal discomfort, mouth ulcers)
• Oral ulcers
• Hepatotoxicity
• Interstitial lung disease

When methotrexate is prescribed, it should be prescribed ONCE A WEEK ONLY (7.5mg, max dose 20mg)

Question 4

Side effects of steroids

Answer 4

• DM
• HTN
• Hx of peptic ulcer
• Osteoporosis
• Mental health problems
• Avascular necrosis
• Infections
• Hyperlipidaemia
• Cataracts, glaucoma
• Myopathy

Question 5

How do you monitor methotrexate?

Answer 5

• FBC + renal + LFTs before starting treatment and repeated weekly until therapy stabilised
• Thereafter patients should be monitored every 2-3 months

Question 6

What can increase methotrexate toxicity?

Answer 6

NSAIDS (inhibit the synthesis of prostaglandins –> fall in renal perfusion –> rise in serum methotrexate levels –> increased toxicity)
Patients should try paracetamol before using NSAIDs

Impaired renal function

Trimethoprim (folate antagonist)
Concomitant administration of folate antagonists increases the antifolate effect of methotrexate and has been reported to cause an acute megaloblastic pancytopenia in rare instances

Question 7

Which drugs can predispose someone to gout?

Answer 7

Aspirin and other salicylates reduce excretion of uric acid and may precipitate acute gout in predisposed patients
Loop diuretics (furosemide) and thiazide diuretics can cause hyperuricaemia and gout

Question 8

Septic arthritis mx

Answer 8

Aspirate the joint fully + joint lavage
Send fluid for urgent gram stain + culture
Take blood culture
Start empirical IV abx immediately