“Steroid Flare” Following Intraarticular Injection of Corticosteroid

 

Clinical features:

(1) onset > 2 hours after the injection

(2) associated with a transient (< 24 hour) and self-limited inflammatory reaction of the injected joint

(3) increase in synovial fluid white blood cells (arthrocentesis often not performed)

(4) more often seen when hydrocortisone acetate is used

(5) exclusion of other causes

 

Differential diagnosis includes:

(1) allergic reaction to the corticosteroid or other component of the injection mixture

(2) crystal-induced arthropathy associated with drug crystals (leukocytosis, negative cultures, crystals seen within macrophages, self-limited)

(3) infection (tends to be progressive, with positive cultures)

(4) hemarthroses