Serum and cerebrospinal fluid neurofilament light chain in patients with central nervous system infections caused by varicella-zoster virus.

Varicella-zoster virus (VZV) is a common cause of viral central nervous system (CNS) infection, and patients may suffer from severe neurological sequelae. The biomarker neurofilament light chain (NFL) is used for assessment of neuronal damage and is normally measured in cerebrospinal fluid (CSF). Novel methods have given the possibility to measure NFL in serum instead, which could be a convenient tool to estimate severity of disease and prognosis in VZV CNS infections. Here, we investigate the correlation of serum and CSF NFL in patients with VZV CNS infection and the association of NFL levels in serum and CSF with different VZV CNS entities. NFL in serum and CSF was measured in 61 patients who were retrospectively identified with neurological symptoms and VZV DNA in CSF detected by PCR. Thirty-three herpes zoster patients and 40 healthy blood donors served as control groups. NFL levels in serum and CSF correlated strongly in the patients with VZV CNS infection. Encephalitis was associated with significantly higher levels of NFL in both serum and CSF compared with meningitis and Ramsay Hunt syndrome. Surprisingly, herpes zoster controls had very high serum NFL levels, comparable with those shown in encephalitis patients. We show that analysis of serum NFL can be used instead of CSF NFL for estimation of neuronal injury in patients with VZV CNS infection. However, high levels of serum NFL also in patients with herpes zoster, without signs of CNS involvement, may complicate the interpretation.

[An autopsied case of severe varicella zoster virus-associated encephalomyelitis under immunosuppressant therapy].

The patient was a 40-year-old woman who was previously diagnosed with systemic lupus erythematosus and myasthenia gravis and had received prednisolone and tacrolimus for more than 7 years. In February 2017, she noticed pain in her lower back and weakness of the lower limbs, and was referred to our hospital on day 5. She had shingles in the right lower thoracic dermatomes and Brown-Séquard syndrome with right-sided dominant weakness in her lower limbs and left-sided superficial sensory disturbance below the L1 level. Varicella zoster virus (VZV)-associated myelopathy was suspected because of her symptoms and clinical findings. Despite the immediate administration of intravenous acyclovir after hospitalization, she lost consciousness and experienced a seizure related to cerebral hemorrhage in the left temporal lobe on the night of day 5. MRI showed enhanced lesions along the spinal cord and leptomeninges of the brainstem and temporal lobe. VZV-IgG and VZV-DNA were positive in the cerebrospinal fluid. Based on these clinical features and laboratory findings, she was diagnosed as VZV-associated vasculopathy and myelopathy. She subsequently had multiple cerebral infractions and hemorrhage, and developed sudden cardiopulmonary arrest on day 6, culminating in death on day 17. Autopsy showed that inflammatory mononuclear cells had infiltrated the vascular walls of the spinal cord. Immunohistochemistry revealed that some neurons and macrophages in the white matter of the spinal cord were positive for VZV. In addition, atrophic neurons, satellite cells surrounding these neurons, and infiltrating macrophages were immune-positive for VZV at the L2 dorsal root ganglia. These findings were consistent with VZV-associated vasculopathy and myelitis. Under immunosuppressive conditions, VZV can cause shingles and neuronal complications such as vasculopathy and myelitis, which are sometimes fatal despite the immediate administration of intravenous acyclovir. New treatment drugs or drugs to prevent VZV activation are desired.

Varicella-Zoster Virus in Cerebrospinal Fluid at Relapses of Multiple Sclerosis is Infective in Vitro.

BACKGROUND: We have reported the presence of varicella-zoster virus (VZV) DNA and viral particles in the cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients during exacerbation. It is not known whether these viruses are infective. AIM: To determine whether the VZV found in CSF of MS patients in exacerbation phase are infective. METHODS: VZV found in CSF of MS patients was quantified by qPCR. Vero E6 cell cultures were incubated with CSF of five MS cases positive for VZV DNA, containing herpes-like viral particles. Propagated virus harvested from these cultures were used to infect new VeroE6 cells. Localization of an immediate-early and a late structural VZV proteins was monitored by confocal microscopy after 72 h. CSF from five non-inflammatory neurological (NIN) patients were used as controls. RESULTS: A cytopathic effect was found in cultured cells inoculated with CSF from MS patients. Both, structural VZV glycoprotein (gB) and immediate-early VZV protein (IE62) were detected in Vero E6 cultures inoculated with samples from all five MS cases. CSF from control patients produced no effect on Vero E6 cells. CONCLUSION: When present in the CSF at relapses of MS, VZV is infective under in vitro conditions.

RNA Polymerase III as a Gatekeeper to Prevent Severe VZV Infections.

In most individuals, varicella zoster virus (VZV) causes varicella upon primary infection and zoster during reactivation. However, in a subset of individuals, VZV may cause severe disease, including encephalitis. Host genetics is believed to be the main determinant of exacerbated disease manifestations. Recent studies have demonstrated that defects in the DNA sensor RNA polymerase III (POL III) confer selective increased susceptibility to VZV infection, thus providing fundamental new insight into VZV immunity. Here we describe the roles of POL III in housekeeping and immune surveillance during VZV infection. We present the latest knowledge on the role of POL III in VZV infection and discuss outstanding questions related to the role of POL III in VZV immunity, and how this insight can be translated into clinical medicine.

Slowly progressing varicella zoster brainstem encephalitis complicating Ramsay Hunt syndrome in an immunocompetent patient: case report and review of the literature.

A 56-year-old immunocompetent male developed brainstem encephalitis complicating Ramsay Hunt syndrome. The disease had a slowly progressing course of months after the triggering infection, much longer than previously reported. Furthermore, magnetic resonance imaging, physical-chemical, and cell count analyses on cerebrospinal fluid were normal, whereas polymerase chain reaction for varicella zoster virus DNA was positive. The simultaneous negativity of both imaging and basic CSF exams is very rare, although possible event which confirms the irreplaceable role of viral screening on CSF. A systematic review of similar reports with highlights on the unusual aspects of our case is also presented.

Defensive Perimeter in the Central Nervous System: Predominance of Astrocytes and Astrogliosis during Recovery from Varicella-Zoster Virus Encephalitis.

UNLABELLED: Varicella-zoster virus (VZV) is a highly neurotropic virus that can cause infections in both the peripheral nervous system and the central nervous system. Several studies of VZV reactivation in the peripheral nervous system (herpes zoster) have been published, while exceedingly few investigations have been carried out in a human brain. Notably, there is no animal model for VZV infection of the central nervous system. In this report, we characterized the cellular environment in the temporal lobe of a human subject who recovered from focal VZV encephalitis. The approach included not only VZV DNA/RNA analyses but also a delineation of infected cell types (neurons, microglia, oligodendrocytes, and astrocytes). The average VZV genome copy number per cell was 5. Several VZV regulatory and structural gene transcripts and products were detected. When colocalization studies were performed to determine which cell types harbored the viral proteins, the majority of infected cells were astrocytes, including aggregates of astrocytes. Evidence of syncytium formation within the aggregates included the continuity of cytoplasm positive for the VZV glycoprotein H (gH) fusion-complex protein within a cellular profile with as many as 80 distinct nuclei. As with other causes of brain injury, these results suggested that astrocytes likely formed a defensive perimeter around foci of VZV infection (astrogliosis). Because of the rarity of brain samples from living humans with VZV encephalitis, we compared our VZV results with those found in a rat encephalitis model following infection with the closely related pseudorabies virus and observed similar perimeters of gliosis. IMPORTANCE: Investigations of VZV-infected human brain from living immunocompetent human subjects are exceedingly rare. Therefore, much of our knowledge of VZV neuropathogenesis is gained from studies of VZV-infected brains obtained at autopsy from immunocompromised patients. These are not optimal samples with which to investigate a response by a human host to VZV infection. In this report, we examined both flash-frozen and paraffin-embedded formalin-fixed brain tissue of an otherwise healthy young male with focal VZV encephalitis, most likely acquired from VZV reactivation in the trigeminal ganglion. Of note, the cellular response to VZV infection mimicked the response to other causes of trauma to the brain, namely, an ingress of astrocytes and astrogliosis around an infectious focus. Many of the astrocytes themselves were infected; astrocytes aggregated in clusters. We postulate that astrogliosis represents a successful defense mechanism by an immunocompetent human host to eliminate VZV reactivation within neurons.

Varicella Zoster Virus Meningoencephalitis Presenting with Elsberg Syndrome without a Rash in an Immunocompetent Patient.

Varicella zoster virus (VZV) infection usually manifests with a skin rash. To the best of our knowledge, this is the first report of a case of VZV meningoencephalitis presenting with Elsberg syndrome without a rash in an immunocompetent patient. Clinicians should consider the potential for VZV infection as well as herpes simplex virus infection in cases of aseptic meningitis accompanied by bladder and rectal disturbances, even in patients without any rash symptoms.

Varicella-zoster virus encephalomyelitis with a prominent demyelinating component.

The histopathologic presentation of varicella-zoster virus (VZV) infection of the central nervous system is varied and is not well understood. Here we report a case of VZV encephalomyelitis with prominent demyelinating pathology in a patient with a history of follicular lymphoma treated with allogeneic stem cell transplantation. The patient presented with waxing and waning bilateral limb weakness and mental status changes. MRI showed leptomeningeal, peripheral spinal cord and periventricular cerebral white matter lesions in the brain, and polymerase chain reaction on cerebrospinal fluid detected VZV DNA. The patient expired from developing atrial fibrillation that rapidly progressed to ventricular fibrillation 10 days after admission to our hospital. Autopsy revealed macrophage-rich areas of demyelination in the spinal cord and cerebrum with relative preservation of axons associated with inclusion bodies and positive immunostaining for VZV. This case represents a rare example of VZV encephalomyelitis presenting with a predominantly demyelinating, "multiple sclerosis-like" pathology. The clinical and histopathologic findings and relevant literature are presented and discussed.

Varicella-zoster vasculitis presenting with cerebellar hemorrhage.

BACKGROUND: Varicella zoster virus (VZV) is known as one of the rare, but important, causes of both ischemic and hemorrhagic stroke. Most previously reported VZV-related hemorrhagic stroke and cerebral vasculitis are associated with anterior circulation because VZV spreads from trigeminal ganglia to the anterior circulation of Willis. The present study presents a patient with cerebellar hemorrhage, who was diagnosed with VZV encephalitis and vasculitis of the posterior inferior cerebellar artery. CASE REPORT: A 75-year-old man with stupor was admitted to our hospital. Computed tomography revealed right intracerebellar hemorrhage, and magnetic resonance imaging revealed multiple high-intense signals throughout the brainstem and temporal lobe on fluid attenuation inversion recovery, suggestive of encephalitis. Cerebral angiography revealed stenosis of left posterior inferior cerebellar artery. Based on cerebrospinal fluid analysis, including anti-VZV IgG antibody and VZV DNA polymerase chain reaction, the patient was diagnosed with VZV encephalitis, vasculitis, and cerebellar hemorrhage. CONCLUSIONS: Both cerebral vasculitis and hemorrhagic stroke due to VZV can occur in the vertebrobasilar system. VZV may enter the central nervous system not only from trigeminal ganglia but also from other pathways. We should be aware that a VZV infection could cause cerebral vasculitis and hemorrhagic stroke in the vertebrobasilar system and in anterior circulation.

VZV encephalitis following successful treatment of CMV infection in a patient with kidney transplant.

A 73-year-old woman with a history of deceased donor kidney transplantation and a recent cytomegalovirus (CMV) infection, presented to the emergency department with an altered mental status. She was found to have varicella zoster virus VZV encephalitis based on cerebrospinal fluid analysis and was treated successfully with intravenous valaciclovir with an improvement in her mental status. A review of the literature shows very few case reports on patients with kidney transplantation developing VZV encephalitis. A few case reports and studies report an association between CMV and VZV infection. In these patients, CMV infection can cause a marked decline in immunity and this predisposes them to other infections. Such associations have also been reported between other types of virus infections from the Herpesviridae family. The risk of disseminated VZV infection increases in the presence of CMV infection.

Varicella zoster CNS vascular complications. A report of four cases and literature review.

This study explored the neurologic vascular complications of varicella zoster virus (VZV). We describe four patients presenting at our institution with neurologic involvement by VZV. MR and MRA studies of the intracranial arterial circulation in the head were read by board-certified radiologists using standard clinical procedures. On MRI, three patients had acute infarcts and in two instances irregularities and narrowings of vessels were visible. Many of these complications are recognized to be due to a vasculopathy affecting small or large vessels and resulting in cerebral infarctions and rarely hemorrhages. The pattern of cerebral infarction and vascular abnormalities is not specific and resembles those of vasculitis/vasculopathy from other causes. The central nervous system (CNS) vascular complications of VZV should be considered in the patients with simultaneous primary or prior VZV infection whose imaging studies show cerebral infarction and/or vasculitic appearing intracranial arteries.

Herpes zoster meningoencephalitis complicated with peripheral vascular disease: an uncommon presentation of a common disease.

Herpes zoster is reactivation of the varicella zoster virus that has remained dormant in the dorsal root ganglia since an earlier episode of chickenpox. Herpes zoster has variable clinical presentations, but meningo-encephalitis is not frequently encountered. There is growing evidence of both large and small vessel involvement in immunocompetent and immunocompromised patients, in contrast with the previous opinion that immunocompetent patients have vasculopathy in the large vessels while immunosuppressed patients have vasculopathy in the small vessels. We present the case of a patient in whom herpes zoster meningoencephalitis was complicated with multifocal vasculopathy with peripheral vascular disease; this is an unusual co-occurrence.

Association between viral load of varicella zoster virus in cerebrospinal fluid and the clinical course of central nervous system infection.

Varicella zoster virus (VZV) like other alphaherpes viruses stays latent after its primary infection. During its reactivation, it can infect the central nervous system (CNS) causing a variety of clinical presentations. Using polymerase chain reaction (PCR) for detection of VZV DNA in cerebrospinal fluid (CSF), it is now recognized in some series as the most common causative agent of viral CNS infection. We aimed to investigate in our study the correlation between VZV viral load in the CSF and the clinical course of its infection, using quantitative real-time PCR. For this purpose, we examined 56 specimens of consecutive patients with positive CSF for VZV DNA in a qualitative test, with a clinical picture of meningitis or encephalitis collected over 10years in Rambam medical center. We found a significant correlation between VZV viral load and the severity and duration of neurological disease. We believe that using quantitative measurement of VZV DNA in the CSF, could serve as a prognostic marker which would influence treatment decisions.

Focal encephalitis following varicella-zoster virus reactivation without rash in a healthy immunized young adult.

Herein we describe an episode of focal varicella-zoster virus (VZV) encephalitis in a healthy young man with neither rash nor radicular pain. The symptoms began with headaches and seizures, after which magnetic resonance imaging detected a single hyperintense lesion in the left temporal lobe. Because of the provisional diagnosis of a brain tumor, the lesion was excised and submitted for pathological examination. No tumor was found. But the tissue immunostained positively for VZV antigens, and wild-type VZV sequences were detected. In short, this case represents VZV reactivation, most likely in the trigeminal ganglion, in the absence of clinical herpes zoster.

Varicella zoster encephalitis mimicking stroke.

Physicians need to consider a broad differential diagnosis when evaluating a patient presenting with a suspected stroke. The rates of overdiagnosis of stroke in studies of consecutive patients vary from 19% to 31%. The two most common stroke mimics are hypoglycemia and seizure, but several etiologies have been reported.We reported the case of a 41-year-old patient presenting to the emergency department with aphasia and right-side hemiparesis, initially suspected to have stroke and finally diagnosed of varicella-zoster encephalitis.