Thrombocytopenic purpura related to rubella infection.

Serologic studies for rubella (hemagglutination inhibition and complement fixation changes) were carried out at two-week intervals in 15 patients with acute idiopathic thrombocytopenic purpura and in age-matched controls in the same season during a small rubella epidemic. Hemagglutination inhibition, sucrose density gradient for hemagglutination inhibition, and complement fixation titer changes implicated recent rubella infection as an etiologic factor in five of the 15 patients.