Donatella Donati

Detection of human herpesvirus-6 in mesial temporal lobe epilepsy surgical brain resections

Background: Human herpesvirus-6 (HHV-6), a ubiquitous β-herpesvirus, is the causative agent of roseola infantum and has been associated with a number of neurologic disorders including seizures, encephalitis/meningitis, and multiple sclerosis. Although the role of HHV-6 in human CNS disease remains to be fully defined, a number of studies have suggested that the CNS can be a site for persistent HHV-6 infection. Objective: To characterize the extent and distribution of HHV-6 in human glial cells from surgical brain resections of patients with mesial temporal lobe epilepsy (MTLE). Method: Brain samples from eight patients with MTLE and seven patients with neocortical epilepsy (NE) undergoing surgical resection were quantitatively analyzed for the presence of HHV-6 DNA using a virus-specific real-time PCR assay. HHV-6 expression was also characterized by western blot analysis and in situ immunohistochemistry (IHC). In addition, HHV-6-reactive cells were analyzed for expression of glial fibrillary acidic protein (GFAP) by double immunofluorescence. Results: DNA obtained from four of eight patients with MTLE had significantly elevated levels of HHV-6 as quantified by real-time PCR. HHV-6 was not amplified in any of the seven patients with NE undergoing surgery. The highest levels of HHV-6 were demonstrated in hippocampal sections (up to 23,079 copies/106 cells) and subtyped as HHV-6B. Expression of HHV-6 was confirmed by western blot analysis and IHC. HHV-6 was co-localized to GFAP-positive cells that morphologically appeared to be astrocytes. Conclusions: HHV-6B is present in brain specimens from a subset of patients with MTLE and localized to astrocytes in the absence of inflammation. The amplification of HHV-6 from hippocampal and temporal lobe astrocytes of MTLE warrants further investigation into the possible role of HHV-6 in the development of MTLE.

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

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.

Peripheral neuropathy associated with anti-myelin basic protein antibodies in a woman vaccinated with rubella virus vaccine

Active immunisation with rubella vaccine has not been commonly associated with neurological complications. We report the case of a 23-year-old woman who developed a mild, distal demyelinating neuropathy after immunisation with the live attenuated RA 27/3 rubella strain. Post-immunisation immunologic studies carried over 24 months showed the presence of antibodies to the RV proteins, particularly to the capsid antigen, and to the myelin basic protein (MBP). A similarity between a C antigen motif and a sequence of the MBP was found by computer analysis. The cross-reactivity was confirmed by immunising mice with a synthetic peptide derived from the MBP, which developed a strong humoral response to RV and MBP. This finding raises the possibility that a virus-induced immune response could lead to an autoaggressive reaction responsible for demyelination.

Successful response of non-recovering Ramsay Hunt syndrome to intravenous high dose methylprednisolone

Ramsay Hunt syndrome (RHS) is a frequent cause of facial palsy. It is a consequence of the infection of geniculate ganglion by herpes zoster or herpes simplex virus. In the lack of randomized controlled trials, RHS is empirically treated by a combination therapy of antiviral agents and steroids given orally. However, RHS has, per se, a poorer prognosis than idiopathic facial palsy (Bells palsy). We describe a case series of two patients with RHS unsuccessfully treated with antiviral drugs and oral corticosteroids, showing an almost complete recovery after late administration of intravenous (i.v.) high dose methylprednisolone. Both patients had all recognized negative prognostic factors including age of onset, a high grade facial weakness, absence of R1 and R2 response at blink reflex test, and in the first case, the involvement of greater superficial petrosal nerve. We propose that i.v. high dose methylprednisolone should be considered, even as a late treatment option, in patients with RHS non recovering after standard antiviral and oral steroid therapy as well as presenting clinical features suggestive of a poor prognosis.

Human herpesvirus 6 infection in autologous bone marrow transplant recipients: A prospective study

After primary infection in early life, human herpesvirus 6 (HHV‐6) remains latent in the body and may reactivate in subjects with poor immune status. A 180‐day longitudinal study of HHV‐6 infection was carried out in 23 autologous bone marrow transplant recipients to evaluate reactivation of HHV‐6; two of these patients underwent a double transplant. The patients were monitored prospectively for HHV‐6 DNA in peripheral blood mononuclear cells (PBMC) by hot start nested PCR. Positive samples were typed by the enzymatic restriction protocol. Positive plasma samples were also tested for HHV‐6 DNA. Antibodies against HHV‐6 were measured by immunofluorescence. Five and two out of 23 patients had intermittent and persistent positivity to HHV‐6 DNA in PBMCs, respectively; four patients carried variant B, and the other three patients both A and B. None of the respective plasma samples were positive. Two patients were positive for HHV‐6 antibodies. Since the significance of HHV‐6 DNA in PBMCs is unclear, these findings do not necessarily indicate active infection but may be due to mild immunosuppression in autologous BMT recipients. J. Med. Virol. 60:39–42, 2000.

Cerebral Circulation Time is Prolonged and Not Correlated with EDSS in Multiple Sclerosis Patients: A Study Using Digital Subtracted Angiography

Literature has suggested that changes in brain flow circulation occur in patients with multiple sclerosis. In this study, digital subtraction angiography (DSA) was used to measure the absolute CCT value in MS patients and to correlate its value to age at disease onset and duration, and to expand disability status scale (EDSS). DSA assessment was performed on eighty MS patients and on a control group of forty-four age-matched patients. CCT in MS and control groups was calculated by analyzing the angiographic images. Lesion and brain volumes were calculated in a representative group of MS patients. Statistical correlations among CCT and disease duration, age at disease onset, lesion load, brain volumes and EDSS were considered. A significant difference between CCT in MS patients (mean = 4.9s; sd = 1.27s) and control group (mean = 2.8s; sd = 0.51s) was demonstrated. No significant statistical correlation was found between CCT and the other parameters in all MS patients. Significantly increased CCT value in MS patients suggests the presence of microvascular dysfunctions, which do not depend on clinical and MRI findings. Hemodynamic changes may not be exclusively the result of a late chronic inflammatory process.

Idiopathic bilateral facial palsy: is a causative role of anti-GM1 ganglioside and herpes simplex type 1 possible?

Bilateral facial nerve palsy (FP) is a rare clinical entity often idiopathic or secondary to several diseases [1]. A role of Herpes simplex virus type 1 (HSV-1) in idiopathic FP is under debate [2]. We report here on a case of bilateral FP associated with anti-GM1 ganglioside antibodies and cerebrospinal HSV-1 DNA, who recovered after therapy with intra-venous immunoglobulins (IVIg). A 68-year-old woman presented a sudden complete right sided FP that, despite treatment (methylprednisolone 40 mg/ day i.m.), became bilateral in 1 week. The clinical history was devoid of relevant pathological events. At day 10 from the onset of symptoms, a neurological examination showed bilateral complete lower motor neuron FP (House-Brackmann grading system V on right and IV on left side). Meanwhile, there was no evidence of motor or sensory impairment of other cranial nerves and limbs, and deep tendon reflexes were normal. Neurophysiology, which included nerve conduction studies, motor, somato-sensory and auditory evoked potentials, was normal. Bilateral stapedial muscle and blink reflexes were absent in keeping with the diagnosis of bilateral facial palsy. MRI showed signs compatible with inflammation in both the facial nerves (Fig. 1). Routine blood investigations, including serological tests, paraneoplastic markers, CSF analysis and neuroimaging studies ruled out several known aetiologies. CSF nested PCR was positive for HSV-1 DNA and negative for other neurotropic viruses. To confirm the CSF positivity and the presence of an active infection, an aliquot of residual frozen CSF sample was thawed and used as inoculum on HSV-1 susceptible HEP cell lines. Though the freeze-thawing procedure may impair the viability of viral particles in biological samples, a cytopathic effect was observed after a 10-day culture (Fig. 2). However, no viral DNA was detected in cell lysates by nested PCR analysis from the same culture. Serum analysis revealed a past infection by HSV-1 since anti-HSV-1 IgG titre was 1:9,900 (v.n. \ 1:230) and the research for anti-HSV-1 IgM was negative. As Guillain–Barre’ (GBS) and Miller Fisher syndrome are likely causes, a serum anti-GM1 and anti-GQ1b antibody (Ab) assay was performed by ELISA. Increased level of anti-GM1 IgG Ab was found (0.083 OD at a dilution 1:640) since absorbance was more than three standard deviations above the mean levels found in serum of normal subjects (normal values \0.050 OD). Anti-GQ1b Ab was negative. Anti-GM2 Ab assay was not performed. No Ab for Borrelia burgdoferi and Campylobacter jejuni was detected in the blood. IVIg therapy (400 mg/kg/day for 5 days) was immediately started, with a prompt improvement. Considering the amelioration of symptoms, the lack of evidence of active infection, and the current orientation for the treatment of facial palsy [3], we avoided the use of antiviral. After 6 months the patient showed a marked clinical recovery (House and Brackmann grade II, residual deficit more pronounced on the right side); serum anti-GM1 Ab was not detectable. E. Pretegiani (&) F. Rosini D. Donati A. Rufa A. Morucci P. Annunziata A. Federico Department of Neurological, Neurosurgical and Behavioural Sciences, University of Siena, Viale Bracci, 53100 Siena, Italy e-mail: pretegiani2@unisi.it