Journal Article

Neurological Manifestations of Influenza Infection in Children and Adults: Results of a National British Surveillance Study

Chow, Gabriel, Absoud, Michael, Lunn, Michael, Lim, Ming, Ledger, Elizabeth, Goenka, Anu, Michael, Benedict D., Lilleker, James, Peake, Deirdre, Carrol, Enitan D., Avula, Shivaram, Hart, Ian J., McKee, David, Kneen, Rachel, Pysden, Karen, Roberts, Mark, Solomon, Tom

2014

Overview

Background. The emergence of influenza A(H1N1) 2009 was met with increased reports of associated neurological manifestations. We aimed to describe neurological manifestations of influenza in adults and children in the United Kingdom that presented at this time. Methods. A 2-year surveillance study was undertaken through the British adult and pediatric neurological surveillance units from February 2011. Patients were included if they met clinical case definitions within 1 month of proven influenza infection. Results. Twenty-five cases were identified: 21 (84%) in children and 4 (16%) in adults. Six (29%) children had preexisting neurological disorders. Polymerase chain reaction of respiratory secretions identified influenza A in 21 (81%; 20 of which [95%] were H1N1) and influenza B in 4 (15%). Twelve children had encephalopathy (1 with movement disorder), 8 had encephalitis, and 1 had meningoencephalitis. Two adults had encephalopathy with movement disorder, 1 had encephalitis, and 1 had Guillain-Barré syndrome. Seven individuals (6 children) had specific acute encephalopathy syndromes (4 acute necrotizing encephalopathy, 1 acute infantile encephalopathy predominantly affecting the frontal lobes, 1 hemorrhagic shock and encephalopathy, 1 acute hemorrhagic leukoencephalopathy). Twenty (80%) required intensive care, 17 (68%) had poor outcome, and 4 (16%) died. Conclusions. This surveillance study described a cohort of adults and children with neurological manifestations of influenza. The majority were due to H1N1. More children than adults were identified; many children had specific encephalopathy syndromes with poor outcomes. None had been vaccinated, although 8 (32%) had indications for this. A modified classification system is proposed based on our data and the increasing spectrum of recognized acute encephalopathy syndromes.

• Publisher: OXFORD UNIVERSITY PRESS,Oxford University Press
• Subject: Adolescent / Adult / Adults / ARTICLES AND COMMENTARIES / Biological and medical sciences / Brain - pathology / Central nervous system / Central Nervous System Diseases - epidemiology / Central Nervous System Diseases - virology / Child / Child, Preschool / Children & youth / Encephalopathies / Female / Frontal lobe / H1N1 subtype influenza A virus / Health surveillance / Human viral diseases / Humans / Immunization / Infant / Infections / Infectious diseases / Influenza A Virus, H1N1 Subtype - isolation & purification / Influenza B virus - isolation & purification / Influenza, Human - epidemiology / Influenza, Human - physiopathology / Male / Medical sciences / Middle Aged / Neurologic manifestations / Neurology / Pediatrics / Polymerase chain reaction / Surveillance / Swine flu / United Kingdom - epidemiology / Viral diseases / Viral diseases of the respiratory system and ent viral diseases