Age: 4.0
Sex: F
Vaccine: DTAP, IPV, MMR, DTAP, IPV, MMR
Symptoms: Haematochezia, Haematuria, Packed red blood cell transfusion, Thrombocytopenic purpura
Clinical narrative: This case was reported in a literature article and described the occurrence of thrombocytopenic purpura in a 4-year-old female subject who was vaccinated with MMR (manufacturer unspecified), IPV and DTaP. On an unspecified date, the subject received unspecified dose of MMR (unknown route of administration, unknown site of injection, batch number not provided), unspecified dose of IPV (unknown route of administration, unknown site of injection, batch number not provided) and unspecified dose of DTaP (unknown route of administration, unknown site of injection, batch number not provided). 4 weeks after vaccination with DTaP, MMR and IPV, the subject experienced thrombocytopenic purpura complicated by hematochezia and hematuria. This case was assessed as medically serious by GSK. The subject was treated with a packed red blood cell transfusion. At the time of reporting, the outcome of the events was unspecified. Summary of the literature article: Immune thrombocytopenic purpura (ITP) was first described after a wild-type measles virus infection in 1952. In 1966, it was reported thrombocytopenia after a live attenuated measles vaccine. Since then, the association of MMR and IPOL has been well established. Immune thrombocytopenia purpura (ITP) is known to occur after many types of infections, including numerous vaccine-preventable diseases. In approximately two-thirds of ITP cases, there is a history of a preceding infectious illness in the days to weeks before ITP onset. Because vaccines are designed to induce an immune response that mimics natural infection to produce immunologic protection, it is theoretically possible that vaccines besides MMR could trigger ITP. In addition, there have been case reports of ITP after other childhood vaccines, including HBV, DTP, and Hep A. The risk of ITP after childhood vaccines other than MMR is unknown. In the literature, known rare severe complications of ITP include intracranial hemorrhage and severe bleeding. Case reports and case series have described severe adverse events after MMR-associated ITP. The risk of severe outcomes of ITP after MMR vaccination is thought to be quite low, but few studies have examined severe complications as an outcome. Using a large population from five managed care organizations, the writers sought to ascertain (1) the risk of ITP in children 6 weeks to 18 years of age after all vaccines routinely administered during childhood and (2) the risk of serious complications of ITP after vaccination in children. Using data from 5 managed care organizations for 2000 to 2009, the writers identified a cohort of 1.8 million children ages 6 weeks to 17 years. Potential ITP cases were identified by using diagnostic codes and platelet counts. All cases were verified by chart review. Incidence rate ratios were calculated comparing the risk of ITP in risk (1 to 42 days after vaccination) and control periods. There were 197 chart-confirmed ITP cases out of 1.8 million children in the cohort. None of the routine childhood vaccines given in the first year of life was significantly associated with an increased risk of ITP. There was no elevated risk of ITP after any vaccine in early childhood other than MMR in the 12- to 19-month age group. There was a significantly elevated risk of ITP after hepatitis A vaccine at 7 to 17 years of age, and for varicella vaccine and Tdap at 11 to 17 years of age. For hepatitis A, varicella, and Tdap, elevated risks were based on one to two vaccine-exposed cases. Most cases were acute and mild with no long-term sequelae. Six of the 197 chart-reviewed cases of ITP had serious adverse events. All of the subjects with serious adverse events developed bleeding requiring hospitalization and/or transfusion, and none had any known long-term complications. There were no deaths. Of the 6 cases of serious adverse events, only one was a vaccine-exposed case, a 4-year-old girl who developed ITP complicated by hematochezia and hematuria requiring a packed red blood cell transfusion 4 weeks after receiving DTaP, MMR, and IPV. ITP is unlikely after early childhood vaccines other than MMR. Because of the small number of exposed cases and potential confounding, the possible association of ITP with hepatitis A, varicella, and Tdap in older children requires further investigation.