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Clinically Mild Encephalopathy With a Reversible Splenial Lesion Type 2 Caused by Human Herpesvirus 6 Infection
Fumikazu Sano1, Toshimichi Fukao1, Kei Tamaru1
1Faculty of Medicine, Department of Pediatrics, University of Yamanashi, Yamanashi, Japan.
Background:
Clinically mild encephalopathy with a reversible splenial lesion (MERS) is the second commonest cause of encephalopathy. Several pathogens have been detected in patients with MERS type 2, such as influenza A and B, but little is known about the proportion of cases of MERS type 2 with this pathogenesis. Human herpesvirus 6 (HHV6) is the second commonest pathogen causing acute encephalopathy. However, HHV6 has not been previously reported in patients with MERS type 2.
Patient Description:
In this report, we describe a five-year-old boy with MERS type 2 caused by HHV6 infection. The present case was diagnosed with MERS type 2 caused by HHV6 infection based on the characteristic clinical course, the results of the virus testing, and imaging findings.
Discussion:
This is the first description of MERS type 2 caused by HHV6 infection. Although there is a report of MERS type 1 caused by HHV6 infection, there are no detailed reports in the literature about MERS type 2 associated with HHV6 infection. Thus the clinical findings associated with MERS type 2 caused by HHV6 infection are poorly understood. This report indicates that HHV6 can cause MERS type 2.
Insights
Human herpesvirus 6 (HHV6) can cause mild encephalopathy with a reversible splenial lesion type 2 (MERS-2). This case report details the first instance of HHV6-induced MERS-2, expanding understanding of MERS-2 pathogenesis.
Area of Science:
- Neurology
- Virology
- Pediatrics
Background:
- Mild encephalopathy with reversible splenial lesion (MERS) is a common neurological condition.
- MERS type 2 has been linked to various pathogens, but the causative agents are not fully understood.
- Human herpesvirus 6 (HHV6) is a known cause of acute encephalopathy, but its role in MERS type 2 was previously unreported.
Observation:
- A five-year-old boy presented with symptoms consistent with MERS type 2.
- Diagnostic investigations, including viral testing and neuroimaging, confirmed HHV6 infection as the cause.
- The patient's clinical course and findings were characteristic of MERS type 2.
Findings:
- This report provides the first documented case of MERS type 2 caused by Human herpesvirus 6 (HHV6) infection.
- The study establishes a link between HHV6 and MERS type 2, a connection not previously detailed in medical literature.
- Clinical findings associated with HHV6-induced MERS type 2 are now better understood.
Implications:
- HHV6 should be considered as a potential cause of MERS type 2.
- This finding contributes to the etiological understanding of MERS type 2.
- Further research is warranted to explore the prevalence and clinical spectrum of HHV6-related MERS type 2.
