Abstract
Immune thrombocytopenia （ITP） is an acquired hemorrhagic disease characterized by isolated idiopathic thrombocytopenia. However, it can also develop after infection. Herein, we report the case of an infant who developed ITP after receiving multiple simultaneous vaccinations. The patient was a 2-month-old boy with no significant perinatal, past, or family history. He received his first vaccinations for Haemophilus influenzae type b, pneumococcus, hepatitis B, and rotavirus at a primary care clinic. After 15 days, he was referred to our hospital because of purpura on his face and upper limbs. On admission, wet purpura was observed on his palate, along with scattered purpura on his face and upper limbs. Hematological analysis revealed a decreased platelet count level of 5,000/µl and elevated level of platelet-associated immunoglobulin G at 65.0ng/107cells. No abnormalities were observed in blood coagulation, chemical values, or complement levels. Therefore, the patient was diagnosed with ITP. Thrombocytopenia improved after intravenous immunoglobulin therapy, and the patient was discharged 6 days after admission. Upon his parents’ request, the next doses of the 4 vaccines were administered separately at 1-month intervals starting at the age of 3 months; the ITP did not recur thereafter. Although the causative vaccine was not identified in this case, ITP was likely associated with administration of simultaneous vaccinations. Including this case, at least 16 pediatric ITP cases followed by vaccination have been reported in Japan. No cases of intracranial hemorrhage or serious neurological sequelae have been reported. There are no clear standards on the resumption or avoidance of simultaneous vaccinations after ITP treatment are lacking. Therefore, individual management of each case is required, with consideration of the parents’ concerns.
