Clinical Characteristics of H1N1 Influenza A-Associated Mild Encephalopathy with Reversible Splenial Lesion: 4 Pediatric Cases

Abstract

Objective

Mild encephalopathy with reversible splenial lesion (MERS) is associated with a variety of infections and anti-epileptic drug withdrawal. Here we report the clinical characteristics of H1N1 influenza A-associated MERS based on our experience of four pediatric cases.

Methods

A detailed retrospective analysis of four patients with H1N1 influenza A-associated MERS was performed at Guangzhou Women and Children’s Medical Center.

Results

All patients exhibited mild influenza-like illness and seizures. Three patients presented with a new-onset seizure with fever after 5 years of age. 75% patients had altered mental status. For all four patients, influenza A (H1N1) viral RNA was detected in throat swab specimens at least twice. Brain magnetic resonance images revealed similar ovoid lesions in the corpus callosum, mainly in the splenium and for one patient in the splenium and genu of the corpus callosum. Only one patient had an abnormal electroencephalogram tracing. Cells and protein in the cerebrospinal fluid were normal in all patients. All patients received oseltamivir and one patient received intravenous immunoglobulin. As a result, all patients fully recovered after 2 months and showed no neurologic sequelae at discharge.

Conclusion

This case series provides insight towards clinical features of H1N1 influenza A-associated MERS.

Keywords

mild encephalopathy with reversible splenial lesion / H1N1 / influenza A / children / corpus callosum / encephalopathy

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