Exacerbation of immune thrombocytopenia following COVID‐19 vaccination

Kuter, David J.

There is concern that COVID‐19 vaccination may adversely affect immune thrombocytopenia (ITP) patients. Fifty‐two consecutive chronic ITP patients were prospectively followed after COVID‐19 vaccination. Fifteen percent had no worsening of clinical symptoms but no post‐vaccination platelet count; 73% had no new symptoms and no significant platelet count decline. However, 12% had a median platelet count drop of 96% within 2–5 days post vaccination with new bleeding symptoms; after rescue therapy with corticosteroids +/− intravenous immunoglobulin (IVIG), platelets recovered to >30 × 10(9)/l a median three days later. ITP exacerbation occurred independently of remission status, concurrent ITP treatment, or vaccine type. Safety of a second vaccine dose needs careful assessment.