Patient selection: therapy with an immune checkpoint inhibitor
Clinical features:
(1) The new onset or worsening of arthralgias or an inflammatory arthritis after starting the ICI.
(2) The exclusion of other causes of an arthritis, including paraneoplastic disease.
(3) Variable resolution of the joint symptoms after discontinuation of the ICI. In some patients the arthritis may persist for some time.
(4) Variable presence of tenosynovitis and synovitis.
(5) Low rates of seropositivity for autoimmune markers and for elevation of inflammatory markers (ESR or CRP).
Risk factors for persistent arthritis after discontinuation of the ICU:
(1) longer duration of ICI therapy
(2) therapy with combinations of ICI drugs
(3) presence of other immune-related adverse effects
The patient may also develop a rheumatologic autoimmune disorder with inflammatory arthritis as one component of a systemic disorder.
