Neuroradiologic findings of brain lesions related to exanthema subitum

HHV-6-Associated Neurological Disease in Children: Epidemiologic, Clinical, Diagnostic, and Treatment Considerations

Human herpesviruses 6A and 6B, often referred to collectively as human herpesvirus 6, are a pair of beta-herpesviruses known to cause a variety of clinical syndromes in both immunocompetent and immunocompromised individuals. Most humans are infected with human herpesvirus 6B, and many with human herpesvirus 6A. Primary infection typically occurs in early childhood, although large-scale reviews on the topic are limited. Herein, the authors explore the clinical manifestations of human herpesvirus 6-associated disease in both immunocompetent and immunocompromised pediatric patients, the risk factors for development of human herpesvirus 6-associated neurological disease, the risk of autoimmunity associated with development of active or latent infection, the relevance of human herpesvirus 6-specific diagnostic tests, and the medications used to treat human herpesvirus 6. The goal of this review is to improve the current understanding of human herpesvirus 6 in pediatric populations and to examine the most effective diagnostic and therapeutic interventions in this disease state.

HHV-6 and seizure: A systematic review and meta-analysis

Human herpesvirus-6 (HHV-6) is a common infection in childhood. This systematic review aims to assess the relationship between HHV-6 infection and seizure disorders based on available literature. MEDLINE database was searched using a search strategy. We included studies that were published after 1993 in English, and described patients with HHV-6 infection and accompanying seizure or status epilepticus. We identified 503 articles, and included 147 studies. Meta-analysis results showed a 0.21 detection rate of HHV-6 in febrile seizure patients. In the febrile seizure group (110 cases), 76 patients had simple and 34 had complex febrile seizures. Patients with "HHV-6 infection and status epilepticus" had a mean age of 16.24 months. In children with febrile illnesses, a higher index of clinical suspicion for HHV-6 infection may be required. Further studies including CSF and brain tissue may be needed to validate relationships between HHV6 infection and epilepsy. J. Med. Virol. 89:161-169, 2017. © 2016 Wiley Periodicals, Inc.

Human herpesvirus 6 encephalopathy predominantly affecting the frontal lobes

Isolated cases of human herpesvirus 6 encephalopathy have recently been reported, although the pathophysiology remains largely unknown. To elucidate the changes specific to human herpesvirus 6 encephalopathy on diagnostic images, this study investigated magnetic resonance imaging findings in 10 patients with a diagnosis of human herpesvirus 6 encephalopathy including diffusion-weighted imaging in 6 of 10, and findings of cerebral blood flow imaging by single-photon emission computed tomography in 9 of 10 patients. No abnormalities were evident on T(1)-weighted, T(2)-weighted, or fluid-attenuated inversion-recovery magnetic resonance imaging during acute phases; however, diffusion-weighted imaging indicated abnormal hyperintensity in the subcortical white matter of the frontal lobes in all six patients during the acute phase. Cerebral blood flow single-photon emission computed tomography revealed decreased perfusion, predominantly in the frontal region of all nine patients during their clinical course. Disturbances predominantly affecting the frontal lobes (region) on magnetic resonance imaging and cerebral blood flow single-photon emission computed tomography were common in all patients, suggesting that the findings may be characteristic of human herpesvirus 6 encephalopathy.