Abstract
Drug induced hypersensitivity syndrome (DIHS) is one of severe adverse reactions of some aromatic antiepileptic drugs (AEDs). High rate of cross-reactivity among these drugs is an obstacle to select alternative AEDs. We report a 1-year-old boy with DIHS due to phenobarbital (PB) followed by complicated adverse effects of multiple alternatives. He had been receiving sodium valproate (VPA) after his epilepsy had developed at 3 months of age, and PB was added at the age of 1 year 2 months because of seizure relapse. 4 weeks later, he had pyrexia, systemic erythematous rash and thrombocytopenia. Serological examinations revealed the reactivation of human herpes virus 6, and the diagnosis of DIHS was made. The above symptoms improved after cessation of PB and VPA, and administration of prednisolone. However DIHS recurred by ZNS, which was administered instead of PB and VPA. Hence VPA was started again to withdraw ZNS, but that induced severe immune thrombocytopenia (IT). VPA is one of the recommended alternatives after DIHS, however it seems that the state of immune-hyperfunction associated with DIHS accelerated VPA-induced IT. We should pay attention to the administration of alternative AEDs including VPA in DIHS patients.
