Clinically Mild Encephalopathy With a Reversible Splenial Lesion Type 2 Caused by Human Herpesvirus 6 Infection.

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.