Febrile seizures associated with influenza A

• Published in: Brain & development (Tokyo. 1979) 2007, Vol.29 (1), p.30-38
• Main Authors: Hara, Keita, Tanabe, Takuya, Aomatsu, Tomoki, Inoue, Nao, Tamaki, Hirohumi, Okamoto, Nami, Okasora, Keisuke, Morimoto, Takahiro, Tamai, Hiroshi
• Format: Article
• Language: English
• Subjects: Age Distribution; Body Temperature - physiology; Causality; Child, Preschool; Comorbidity; Consciousness Disorders - epidemiology; Consciousness Disorders - physiopathology; Consciousness Disorders - virology; Febrile seizures; Female; Fever - complications; Fever - physiopathology; Humans; Influenza A; Influenza A virus - immunology; Influenza, Human - diagnosis; Influenza, Human - epidemiology; Influenza, Human - virology; Japan - epidemiology; Male; Postictal impaired consciousness; Prospective Studies; Regression Analysis; Seizures, Febrile - epidemiology; Seizures, Febrile - physiopathology; Seizures, Febrile - virology; Serologic Tests
• ISSN: 0387-7604; 1872-7131
• DOI: 10.1016/j.braindev.2006.05.010

To clarify the clinical impact of influenza A on the development of febrile seizures (FS), consecutive FS patients brought to our hospital between October 2003 and September 2004 were prospectively surveyed. Patients infected with influenza A (influenza A patients) and those uninfected with influenza (non-influenza patients) were compared with regard to clinical characteristics of FS. Influenza infection was determined by rapid antigen test and/or serologically. Associations of influenza A with atypical findings of FS, including partial seizures, prolonged seizures, multiple seizures during the same illness, and 30-min or longer prolonged postictal impairment of consciousness (PPIC), were analyzed by multiple logistic regression. A total of 215 patients (47 influenza A and 168 non-influenza patients) were enrolled in the study. Age was significantly higher in the influenza A group (39.85 ± 22.16 months vs. 27.51 ± 17.14 months, P < 0.001). Of 42 patients aged 48 months or older, which corresponded to the 80th percentile for age, 15 (35.7%) were influenza A patients, with a significantly higher incidence of such patients than in the subgroup of patients aged 47 months or younger (32/173, 18.5%) ( P = 0.015). On multiple logistic regression analysis, influenza A was independently associated with PPIC (odds ratio: 4.44, 95% confidence interval: 1.52–12.95, P = 0.006), but not with other atypical findings. The positive association of influenza A with PPIC suggests that influenza may affect state of consciousness at the same time that it induces seizures with fever.