Thrombocytopenic purpura following varicella-zoster vaccination.

Acute thrombocytopenia developed 3 weeks after the vaccination of a child with leukemia with V-Z vaccine. This is the first case of postvaccinal thrombocytopenia to be reported following V-Z vaccine. The risk to leukemic children of postvaccinal thrombocytopenia would appear to be less than 1%. Note added in proof: The patient remained seronegative until the eighth month following vaccination. Her FAMA titer then rose to 1:32, probably as a result of exogenous reinfection with V-Z virus.