Encephaloradiculomyelitis associated to HHV-7 and CMV co-infection in immunocompetent host

Abstract

An active co-infection with CMV and HHV-7 has been never described in immunocompetent patients. The authors describe a case of encephaloradiculomyelitis in an immunocompetent man. Polymerase chain reaction (PCR) performed on cerebrospinal fluid (CSF) showed positivity for DNA of Cytomegalovirus (CMV) and Herpes-virus type 7 (HHV-7), whereas the same test applied on peripheral blood mononuclear cells gave negative result. These results are highly supportive of an infection of the central and peripheral nervous systems, caused by CMV and HHV7. Such viral co-infection has only been described in immune-depressed patients with CMV disease, in which HHV-7 was supposed to act as a cofactor, enhancing clinical manifestations. The same mechanism is presumably responsible for the development of encephaloradiculomyelitis clinical signs in the present case. This is the second case in which DNA of HHV-7 has been found in the CSF of an adult immunocompetent patient. This novel observation suggests that the search for viral DNA in the CSF should be performed also in immunocompetent patients.