Neuroinvasion by human herpesvirus type 7 in a case of exanthem subitum with severe neurologic manifestations

Abstract

A 19-month-old girl presented with severe neurologic symptoms associated with exanthem subitum. Human herpesvirus type 7 (HHV-7) DNA was detected in the CSF and serum, and supported by serologic studies. The patient was diagnosed with encephalopathy due to an acute HHV-7 infection. Neuron-specific enolase in the CSF was strongly elevated during the acute stage of infection, suggesting that the encephalopathy was due to viral invasion of the brain.

Human herpesvirus-7 infection of the CNS with acute myelitis in an adult bone marrow recipient

“…As regards the role of the HHV-7 infection in the aetiology of the patient's acute myelitis, it has recently been shown that delayed primary infection in an adult can cause neurological disease 8 as has been known to occur in children. 4,5 Therefore, although there has been no previous report of HHV-7 infection specifically associated with acute myelitis in individuals of any age whether immunocompromised or immunocompetent, it seems that the reactivated HHV-7 infection in the present adult case may indeed have caused the patient's illness.…”

“…The two viruses in the Roseolovirus genus of ␤-herpesviruses, ie human herpesviruses-6 and -7 (HHV-6 and -7), are obvious candidates since primary infection with either virus has been associated with childhood neurological illness and neuroinvasion. [3][4][5] In adults, HHV-6 infection has already been associated with encephalitis in both the immunocompetent 6 and immunocompromised including after stem cell transplant. 7 As regards HHV-7 and adults, a unique case of delayed primary infection with neuroinvasion, encephalitis and flaccid paralysis has recently been described 8 but there have been no reports of HHV-7 infection accompanied by disease of the central nervous system after stem cell transplant or in any other immunocompromised adults.…”

Polirradiculoneuritis aguda asociada a infección por Virus Herpes Humano 7 en un paciente adulto inmunocompetente

“…El rol patogénico de este virus fue reconocido en la década de los 90s, cuando se describió el primer caso de crisis febril y exantema súbito, asociado a compromiso neurológico severo 6 . Desde entonces, pequeñas series y reportes de casos, han presentado un amplio rango de manifestaciones neurológicas, incluyendo casos de meningitis leves autolimitadas, casos de encefalitis severas y mielitis con polirradiculoneuritis [3][4][5]7,8 .…”

Immune Reactivity of Human Sera to the Glycoprotein B of Human Herpesvirus 7

“…The natural history of HHV-7 infection in the human host is not well known. Primary infection has not yet been consistently associated with a given disease, and the potential association of HHV-7 reactivation with diseases in adults remains to be confirmed (11,22,32,33,40,43,45).These pending questions point out the need for relevant diagnostic tools targeted to HHV-7 infection. So far, the serological diagnosis of HHV-7 infection has raised concerns about its specificity (3, 14, 38) because HHV-7 has marked homologies with the two other human betaherpesviruses, HHV-6 and, to a lesser extent, human cytomegalovirus (HCMV).…”

“…The natural history of HHV-7 infection in the human host is not well known. Primary infection has not yet been consistently associated with a given disease, and the potential association of HHV-7 reactivation with diseases in adults remains to be confirmed (11,22,32,33,40,43,45).…”