Immune Toxicity with Checkpoint Inhibition for Metastatic Melanoma: Case Series and Clinical Management

Table 5

Suggested algorithm arthralgia and arthritis.

Rheumatological irAE	Investigations	Management
Grade 1/mild
Arthralgia and arthritis (minimal symptoms or signs)		Continue checkpoint inhibitor therapy; Simple analgesia as required
Grade 2/moderate
Arthralgia and arthritis (moderate pain, inflammation, and impacting on daily function)	Exclude: Sepsis, crystal-induced arthritis, and coincidental inflammatory arthritis; Perform: Synovial fluid cell count, polarised microscopy for crystals, gram stain and culture, blood culture; RF, CCP, ANA, HLA-B27 (if positive, consider coincidental disease)	Consider delay of checkpoint inhibitor therapy; Consider rheumatology referral; Monoarthritis or oligoarthritis: Consider intra-articular corticosteroid; Moderate inflammatory arthritis: Consider low dose prednisolone 5–10 mg daily; For more significant symptoms, higher doses may be required, for example, prednisolone 25 mg daily; If response is not rapid, consider addition of sulphasalazine (immunomodulator without immunosuppressive effect)
Grade 3-4/severe/life-threatening
Arthralgia and arthritis (severe pain or inflammation, disabling, and impacting on self-care)	Exclude: Sepsis, crystal-induced arthritis, and coincidental inflammatory arthritis; Perform: Synovial fluid cell count, polarised microscopy for crystals, gram stain and culture, blood culture; RF, CCP, ANA, HLA-B27 (if positive, consider coincidental disease)	Discontinue immunotherapy; Rheumatology referral; Moderate-severe inflammatory arthritis: Prednisolone 25 mg–40 mg daily; If response is not rapid, consider addition of sulphasalazine; Severe: Pulse with methylprednisolone 1-2 mg/kg/day for 3 days

Switch to oral prednisolone 1 mg/kg/day with slow taper over 1 month or longer. PJP (e.g., bactrim DS 1/2 tablet daily) and GIT ulcer prophylaxis therapy when patients are on prolonged steroid taper. Monitor blood glucose.