Acute Necrotizing Encephalopathy of Childhood due to Influenza Type A Virus

A 1 year and 11 month-old boy developed convulsions and disturbance of consciousness after an antipyretic was administered. Influenza type A virus reaction was positive on rapid antigen test of nasal discharge. Although no significant abnormality was found by brain CT on admission, abnormal densities were observed in the bilateral thalami, brain stem and tegmentum on brain CT performed 12 hours later, so the patient was diagnosed with acute necrotizing encephalopathy (ANE) of childhood due to influenza type A virus. In spite of we diagnosed and performed methylprednisolone pulse and antithrombin III therapy in the early stage of this encephalopathy, which resulted in serious neurologic sequelae remaining. The clinical course of our case suggests that the early diagnosis and these treatments for ANE may not be effective. At present, we have no established therapy for this encephalopathy, so the vaccination is only a method for prevention of ANE due to influenza type A virus