week 8 gout and msk

Question 1

Allopurinol

Answer 1

Class: Xanthine Oxidase Inhibitor

MoA: Blocks conversion of purines to uric acid

Rare/Serious AEs: Stevens Johnson Syndrome/Toxic Epidermal Necrolysis/DRESS

Pearl: SJS more common in people with HLA-B*5801 Allele

Question 2

Febuxostat

Answer 2

Class: Xanthine Oxidase Inhibitor

MoA: Inhibits xanthine oxidase → ↓ uric acid

Adverse Effects: Rash, N/V, abnormal LFTs; ↑ CV death in CVD

Indications: Gout prophylaxis

Pearl: Black box warning for CV death; flare risk at start

Question 3

Pegloticase

Answer 3

Class: Recombinant Uricase

MoA: Converts uric acid to allantoin (water-soluble)

Adverse Effects: Infusion reactions

Indications: Severe refractory gout

Pearl: IV only; screen for G6PD deficiency

Question 4

Probenecid

Answer 4

Class: Uricosuric

MoA: Inhibits renal uric acid reabsorption → ↑ excretion

Adverse Effects: Rash, uric acid kidney stones

Indications: Gout (not for stone-formers)

Pearl: Avoid in patients with uric acid nephrolithiasis

Question 5

Colchicine

Answer 5

Class: Anti-inflammatory (non-NSAID)

MoA: Inhibits beta-tubulin polymerization → ↓ neutrophil activity

Adverse Effects: Diarrhea, myopathy; Rare: myelosuppression, nephrotoxicity

Indications: Gout flare, pseudogout, pericarditis

Pearl: Use within 36h of flare; many drug interactions

Question 6

Topical Steroids (e.g., Clobetasol, Hydrocortisone)

Answer 6

Class: Topical corticosteroids

MoA: Anti-inflammatory effects

Adverse Effects: Skin atrophy, acne, hypopigmentation

Indications: Dermatitis, psoriasis, vitiligo, lupus rashes

Pearl: Ointments are more potent

Question 7

Prednisone, Methylprednisolone

Answer 7

Class: Glucocorticoids

MoA: ↓ cytokines, prostaglandins, leukotrienes

Adverse Effects: Hyperglycemia, weight gain, osteoporosis, adrenal suppression

Indications: Gout flare, multiple inflammatory diseases

Pearl: Various forms (oral, IV, intra-articular)