PT - JOURNAL ARTICLE AU - Khandaker, Gulam AU - Zurynski, Yvonne AU - Buttery, Jim AU - Marshall, Helen AU - Richmond, Peter C. AU - Dale, Russell C. AU - Royle, Jenny AU - Gold, Michael AU - Snelling, Tom AU - Whitehead, Bruce AU - Jones, Cheryl AU - Heron, Leon AU - McCaskill, Mary AU - Macartney, Kristine AU - Elliott, Elizabeth J. AU - Booy, Robert TI - Neurologic complications of influenza A(H1N1)pdm09 AID - 10.1212/WNL.0b013e31826d5ea7 DP - 2012 Oct 02 TA - Neurology PG - 1474--1481 VI - 79 IP - 14 4099 - http://n.neurology.org/content/79/14/1474.short 4100 - http://n.neurology.org/content/79/14/1474.full SO - Neurology2012 Oct 02; 79 AB - Objective: We sought to determine the range and extent of neurologic complications due to pandemic influenza A (H1N1) 2009 infection (pH1N1′09) in children hospitalized with influenza. Methods: Active hospital-based surveillance in 6 Australian tertiary pediatric referral centers between June 1 and September 30, 2009, for children aged <15 years with laboratory-confirmed pH1N1′09. Results: A total of 506 children with pH1N1′09 were hospitalized, of whom 49 (9.7%) had neurologic complications; median age 4.8 years (range 0.5–12.6 years) compared with 3.7 years (0.01–14.9 years) in those without complications. Approximately one-half (55.1%) of the children with neurologic complications had preexisting medical conditions, and 42.8% had preexisting neurologic conditions. On presentation, only 36.7% had the triad of cough, fever, and coryza/runny nose, whereas 38.7% had only 1 or no respiratory symptoms. Seizure was the most common neurologic complication (7.5%). Others included encephalitis/encephalopathy (1.4%), confusion/disorientation (1.0%), loss of consciousness (1.0%), and paralysis/Guillain-Barré syndrome (0.4%). A total of 30.6% needed intensive care unit (ICU) admission, 24.5% required mechanical ventilation, and 2 (4.1%) died. The mean length of stay in hospital was 6.5 days (median 3 days) and mean ICU stay was 4.4 days (median 1.5 days). Conclusions: Neurologic complications are relatively common among children admitted with influenza, and can be life-threatening. The lack of specific treatment for influenza-related neurologic complications underlines the importance of early diagnosis, use of antivirals, and universal influenza vaccination in children. Clinicians should consider influenza in children with neurologic symptoms even with a paucity of respiratory symptoms. APSU=Australian Pediatric Surveillance Unit; CHW=Children's Hospital at Westmead; CI=confidence interval; EL=encephalitis lethargica; GBS=Guillain-Barré syndrome; HAPS=Hunter Area Pathology Service; ICU=intensive care unit; ILAE=International League Against Epilepsy; ILI=influenza-like illness; JHCH=John Hunter Children's Hospital; LOS=length of stay; NCIRS=National Centre for Immunization Research and Surveillance; PAEDS=Pediatric Active Enhanced Disease Surveillance; PMH=Princes Margaret Hospital Perth; RCH=Royal Children's Hospital Melbourne; SCH=Sydney Children's Hospital; SEALS=South Eastern Area Laboratory Service; VIDRL=Victorian Infectious Diseases Reference Laboratory; WCH=Women's and Children's Hospital Adelaide.