[Clinical analysis of seven cases of H1N1 influenza-associated encephalopathy in children]

Objective: To investigate the clinical manifestations, diagnosis, and treatment of H1N1 influenza A-associated encephalopathy (IAE) in children. Methods: The clinical manifestations, laboratory tests, cranial magnetic resonance imaging (MRI), electroencephalography (EEG) examinations and treatments of seven children with H1N1 IAE hospitalized in Guangzhou Women and Children's Medical Center from December 2018 to January 2019 were retrospectively analyzed. Results: Five of the seven children with H1N1 IAE were female. The age at admission was 4 years and 5 months (range 7 months-9 years). Neurological symptoms occurred simultaneously or early (0-3 days) after the flu-like symptom appeared. The main clinical manifestations of neurological symptoms were seizures (repeated seizures in five cases and status convulsion in two cases, including one case of unexpected fever and repeated seizures in a nine-year old girl) accompanied with altered consciousness (drowsiness in five cases and coma in two cases). Cranial MRI in three cases displayed multifocal lesions, mainly in the bilateral thalamus, brainstem and cerebellar hemisphere. MRI also showed reversible splenial lesion in the corpus callusumin in three cases. EEG tracings were characterized by diffuse slow wave activity in four cases, and status epilepticus was monitored in one case. All the 7 cases were treated with oral oseltamivir. Three cases were treated with pulsed methylprednisolone and intravenous immunoglobulin. One case was treated with intravenous immunoglobulin alone and all the patients received oral oseltamivir. All the patients survived, with three patients had minor neurological sequelae at discharge. Conclusions: The main clinical manifestations of H1N1 IAE are seizures and altered consciousness. Cranial MRI combined with EEG is helpful for early diagnosis. Intravenous immunoglobulin and (or) methylprednisolone should be considered for severe cases.