2019 Volume 33 Issue 3 Pages 288-294
Drug-induced hypersensitivity syndrome is one of the severe drug eruptions triggered by oral administration of drugs such as antiepileptics and antibiotics. One of the diagnostic criteria for this syndrome is an increase in peripheral blood eosinophil count (>1,500/μL). We report the case of a 15-year-old boy with no previous history of allergy who was apparently healthy until he had an afebrile convulsion twice, for which oral administration of carbamazepine was started. Fever and erythema appeared 3 weeks after the treatment initiation ; furthermore, hepatic dysfunction, as well as a marked increase in white blood cell (36,440/μL) and eosinophil (21,499/μL) counts was observed. Treatment with a steroid was started, and carbamazepine was discontinued, following which the symptoms became mild and eosinophil count decreased. Drug-induced lymphocyte stimulation test result for carbamazepine was positive ; reactivation of human herpesvirus 6 was confirmed, and the criteria for drug-induced hypersensitivity syndrome was satisfied. Eosinophilia was remarkable, and additional examinations revealed abnormally high thymus and activation-regulated chemokine and interleukin-5 levels as well as aberrant T cell, which are some of the characteristics of lymphocytic hypereosinophilic syndrome ; this possibly explains some of the pathological conditions observed in drug-induced hypersensitivity syndrome.
