Acute Necrotizing Encephalopathy – A Rare Complication of H1N1 Infection

  • Andreia Alves Martins Department of Pediatric, Hospital Pedro Hispano. Unidade Local de Saúde de Matosinhos
  • Inês Dias Department of Pediatric, Hospital Santo André, Centro Hospitalar de Leiria
  • Andrea Dias Department of Pediatric Intensive Care, Hospital Pediátrico de Coimbra, Centro Hospitalar Universitário de Coimbra
  • Rita Moinho Department of Pediatric Intensive Care, Hospital Pediátrico de Coimbra, Centro Hospitalar Universitário de Coimbra
  • Carla Pinto Department of Pediatric Intensive Care, Hospital Pediátrico de Coimbra, Centro Hospitalar Universitário de Coimbra
  • Leonor Carvalho Department of Pediatric Intensive Care, Hospital Pediátrico de Coimbra, Centro Hospitalar Universitário de Coimbra
Keywords: Encephalopathy, Influenza A Virus H1N1 Subtype, Preschool children

Abstract

Acute necrotizing encephalopathy is a rare complication of H1N1 influenza infection, more prevalent in preschool children. It is characterized by a rapid neurological deterioration with progressive decline on the level of consciousness in the context of a febrile disease, associated with multifocal symmetric brain lesions.
The cases of two children (two and four years old) admitted due to an altered level of conscience in the context of febrile respiratory infection are described. The laboratory studies disclosed high aminotransferases with normal ammonia, and the presence of H1N1 virus in the nasopharyngeal swab. The brain computed tomography showed bilateral thalamic hypodensities. The clinical evolution was very distinctive in the two cases, with brain death in one and survival with good neurological outcome in the other.
The association of febrile respiratory infection and a rapid decline on the level of consciousness should be an alert to this entity, which has high morbidity and mortality. For the diagnosis, it is recommended to search for the virus in the nasopharyngeal swab. In addition to supportive treatment, oseltamivir and immunomodulators, although controversial, are the most commonly used therapies.

References

Martin A, Reade EP. Acute Necrotizing Encephalopathy Progressing to Brain Death in a Pediatric Patient with Novel Influenza A (H1N1) Infection. Clin Infect Dis. 2010; 50:50-2.

Gulati P, Saini L, Jawa A, Das CJ. MRI in H1N1 Encephalitis. Indian J Pediatr. 2013; 80:157-9.

Wilking AN, Elliott E, Garcia MN, Murray KO, Munoz FM. Central Nervous System Manifestations in Pediatric Patients With Influenza A H1N1 Infection During the 2009 Pandemic. Pediatr Neurol. 2014; 51:370-6.

Amin R, Ford-Jones E, Richardson SE, MacGregor D, Tellier R, Heurter H, et al. Acute Childhood Encephalitis and Encephalopathy Associated With Influenza - A Prospective 11-Year Review. Pediatr Infect Dis J. 2008; 27:390-5.

Zeng H, Quinet S, Huang W, Gan Y, Han C, He Y, et al. Clinical and MRI features of neurological complications after influenza A (H1N1) infection in critically ill children. Pediatr Radiol. 2013; 43:1182-9.

Lyon JB, Remigio C, Milligan T, Deline C. Acute necrotizing encephalopathy in a child with H1N1 influenza infection. Pediatr Radiol. 2010; 40:200-5.

Bustos BR, Andrade YF. Acute encephalopathy and brain death in a child with influenza A (H1N1) during the 2009 pandemic. Rev Chilena Infectol. 2010; 27:413-6.

Kim KJ, Park ES, Chang HJ, Suh M, Rha DW. Novel Influenza A (H1N1)-Associated Acute Necrotizing Encephalopathy: A Case Report. Ann Rehabil Med. 2013; 37:286-90.

Akins PT, Belko J, Uyeki TM, Axelrod Y, Lee KK, Silverthorn J. H1N1 Encephalitis with Malignant Edema and Review of Neurologic Complications from Influenza. Neurocrit Care. 2010; 13:396-406.

Saab S, Torres JB, Serrano S, Rodriguez N. Encefalopatía necrotizante aguda de la infancia. diagnóstico por imágenes: presentación de caso. Rev. Colomb. Radiol. 2015; 26:4223-7.

Wu X, Wu W, Pan W, Wu L, Liu K, Zhang HL. Acute Necrotizing Encephalopathy: An Underrecognized Clinicoradiologic Disorder. Mediators Inflamm. 2015; 2015:792578.

Vargas WS, Merchant S, Solomon G. Favorable outcomes in acute necrotizing encephalopathy in a child treated with hypothermia. Pediatr Neurol. 2012; 46:387-9.

Published
2018-07-13
Section
Case Reports