Immune thrombocytopenia (ITP) is an isolated autoimmune condition, often preceded by a viral infection. Vaccines, mainly the measles-mumps-rubella vaccine, have also been associated with an increased risk of developing the disease. Although some case reports of ITP after influenza immunization in adults have been published, epidemiologic studies examining the role of the influenza vaccine as a trigger of ITP have not conclusively proven causality. We report a child with 3 occurrences of ITP, each within 1 week of receiving the influenza trivalent inactivated vaccine. He recovered fully in-between the episodes, and no further episodes have occurred since discontinuation of seasonal influenza vaccination. To the best of our knowledge, this report is the first showing, with high probability, the influenza vaccine as a cause for ITP in a pediatric patient.
