The varicella zoster virus vasculopathies: clinical, CSF, imaging, and virologic features

Perspectives in neonatal and childhood arterial ischemic stroke

INTRODUCTION

Over the last decade considerable advances have been made in the identification, understanding and management of pediatric arterial ischemic stroke. Such increasing knowledge has also brought new perspectives and interrogations in the current acute and rehabilitative care of these patients. Areas covered: In developed countries, focal cerebral arteriopathy is one of the most common causes of arterial ischemic stroke in childhood and imaging features are well characterized. However, there are ongoing debates regarding its underlying mechanisms, natural evolution and proper management. The implementation of thrombolytic therapy in acute pediatric stroke has been shown to be efficient in anecdotal cases but is still limited by a number of caveats, even in large tertiary centers. Finally, neonatal stroke represents a unique circumstance of possible early intervention before the onset of any neurological disability but this appears meaningful only in a selective group of neonates. Expert commentary: While perinatal stroke, a leading cause of cerebral palsy, appears to be multifactorial, a large number of childhood ischemic stroke are probably essentially triggered by infectious factors leading to vessel wall damage. Current research is aiming at better identifying risk factors in both conditions, and to define optimal acute and preventive therapeutic strategies in order to reduce significant long-term morbidity.

The Role of Catheter Angiography in the Diagnosis of Central Nervous System Vasculitis

BACKGROUND

Central nervous system vasculitis (CNSV) is a rare disorder, the pathophysiology of which is not fully understood. It involves a combination of inflammation and thrombosis. CNSV is most commonly associated with headache, gradual changes in mental status, and focal neurological symptoms. Diagnosis requires the effective use of history, laboratory testing, imaging, and biopsy. Catheter angiography can be a powerful tool in the diagnosis when common and low-frequency angiographic manifestations of CNSV are considered. We review these manifestations and their place in the diagnostic algorithm of CNSV.

SUMMARY

We reviewed the PubMed database for case series of CNSV that included 5 or more patients. Demographic and angiographic findings were collected. Angiographic findings were dichotomized between common and low-frequency findings. A system for incorporating these findings into clinical decision-making is proposed.

KEY MESSAGE

CNSV is a diagnostic challenge due to the absence of a true gold standard test. In the absence of such a test, catheter angiography remains a central piece of the diagnostic puzzle when appropriately employed and interpreted.

Successful antiviral treatment after 6years of chronic progressive neurological disease attributed to VZV brain infection

We describe an extraordinary case of an immunocompetent patient who developed sacral-distribution zoster, followed 3months later by neurological disease that progressed for 6years and was attributed to varicella zoster virus (VZV) infection of the brain. Despite the prolonged infection, neurologic symptoms and signs resolved rapidly and completely after treatment with intravenous acyclovir.

A Young Woman with Ischemic Stroke: Should We Pay More Attention to Varicella Zoster Infection?

Ischemic and hemorrhagic stroke are recognized complications of Varicella zoster virus (VZV) infections, although uncommon and poorly documented. The authors report the case of a 31-year-old woman admitted with acute ischemic stroke of the right posterior cerebral artery and a history of a thoracic rash 1 month before. Aspirin and simvastatin were prescribed, but the patient suffered a stepwise deterioration the following days, with new areas of infarction on brain imaging. Despite no evidence of cardiac or large vessel embolic sources, anticoagulation was started empirically 6 days after stroke onset. One week later, symptomatic hemorrhagic transformation occurred. The diagnosis of VZV vasculopathy was then considered, and treatment with acyclovir and prednisolone was started with no further vascular events. Cerebrospinal fluid analysis and digital subtraction angiography findings corroborated the diagnosis. The patient was discharged to the rehabilitation center with a modified Rankin scale (mRS) score of 4. On the 6-month follow-up, she presented only a slight disability (mRS score 2). In conclusion, VZV vasculopathy needs to be considered in young adults with stroke. A high index of suspicion and early treatment seem to be important to minimize morbidity and mortality. Anticoagulation should probably be avoided in stroke associated with VZV vasculopathy.

Arterial ischemic stroke in HIV: Defining and classifying etiology for research studies

HIV infection, and potentially its treatment, increases the risk of an arterial ischemic stroke. Multiple etiologies and lack of clear case definitions inhibit progress in this field. Several etiologies, many treatable, are relevant to HIV-related stroke. To fully understand the mechanisms and the terminology used, a robust classification algorithm to help ascribe the various etiologies is needed. This consensus paper considers the strengths and limitations of current case definitions in the context of HIV infection. The case definitions for the major etiologies in HIV-related strokes were refined (e.g., varicella zoster vasculopathy and antiphospholipid syndrome) and in some instances new case definitions were described (e.g., HIV-associated vasculopathy). These case definitions provided a framework for an algorithm to help assign a final diagnosis, and help classify the subtypes of HIV etiology in ischemic stroke.

Transcranial Color-Coded Duplex in Acute Encephalitis: Current Status and Future Prospects

BACKGROUP AND PURPOSE

There are limited data regarding the diagnostic yield of transcranial color-coded Doppler (TCCD) in acute encephalitis. We present our preliminary observations of consecutive ultrasound evaluations in 2 patients with acute encephalitis and we review the possible diagnostic role of TCCD in such cases.

METHODS

We describe two cases of acute encephalitis that presented with aphasia and confusion and underwent repeat TCCD evaluation at baseline and after 48 hours in both patients. We also critically review the current literature regarding potential TCCD applications in acute central nervous system infections.

RESULTS

Serial TCCD evaluations revealed the following triad of abnormal findings in both patients: (i) elevated pulsatility index (PI) in the left middle cerebral artery (M1 MCA) at baseline (>1.2), (ii) increased PI in left M1 MCA by >25% in comparison to right M1 MCA, and (iii) decrease in PI in left M1 MCA by >25% at the follow-up evaluation at 48 hours. The decrease in PI in left M1 MCA coincided with symptom improvement in both patients.

DISCUSSION

The focal transient increase in left M1 MCA PI may be attributed to focally increased intracranial pressure or peripheral vasospasm of distal left MCA branches. Since there are limited reports in the literature concerning TCCD evaluation of patients with central nervous system infections, our preliminary findings require independent confirmation in a larger series of patients.

A study on viral CNS inflammation beyond herpes encephalitis

The early diagnosis of herpes simplex virus encephalitis (HSVE) enables induction of antiviral therapy in this potentially life-threatening disease. The study aimed to determine clinical findings including cerebrospinal fluid (CSF) data and MRI imaging in HSVE patients and to identify features distinguishing HSVE from encephalitis of other viral etiologies. We retrospectively reviewed consecutive patients who were diagnosed with viral encephalitis between 2000 and 2014 at the University Hospital Halle. Forty-nine patients with viral encephalitis were identified. A viral etiology could be confirmed by PCR or antibody testing in 22/49 (44.9 %) of patients (15 (30.6 %) HSV, 5 (10.2 %) VZV, 2 (4.1 %) EBV). In HSVE, typical findings were focal slowing in electroencephalophy (EEG) (80 %, p = 0.021) and presence of cortical (86.7 %, p = 0.030) lesions in MRI. Restricted diffusion was particularly helpful in detection of early signal abnormalities in HSVE (p = 0.014). In 27/49 (55.1 %) of patients, no causative agent could be elucidated. In these patients, 15/27 (55.6 %) experienced a rather "benign" disease course with no MRI pathology despite initially HSVE mimicking clinical picture. However, CSF was significantly different showing a higher amount of granulocytes and activated lymphocytes. The remaining 12/27 (44.4 %) patients developed MRI changes consistent with encephalitis, in 4 of these patients, disease course was fatal. Beside PCR-based serology as standard procedure, MRI including diffusion-weighted images and EEG represent additional tools in early HSVE diagnosis. CSF cytology might be particularly supportive in differentiating likely benign forms of encephalitis.

Varicella Zoster Virus: A Common Cause of Stroke in Children and Adults

BACKGROUND

Varicella zoster virus (VZV) is a neurotropic, exclusively human herpesvirus. Primary infection causes varicella (chickenpox), after which the virus becomes latent in ganglionic neurons along the entire neuraxis. As cell-mediated immunity to VZV declines with advancing age and immunosuppression, VZV reactivates to produce zoster (shingles). One of the most serious complications of zoster is VZV vasculopathy.

METHODS

We reviewed recent studies of stroke associated with varicella and zoster, how VZV vasculopathy is verified virologically, vaccination to prevent varicella and immunization to prevent zoster, and VZV in giant cell arteritis (GCA).

FINDINGS

We report recent epidemiological studies revealing an increased risk of stroke after zoster; the clinical, laboratory, and imaging features of VZV vasculopathy; that VZV vasculopathy is confirmed by the presence of either VZV DNA or anti-VZV IgG antibody in cerebrospinal fluid; special features of VZV vasculopathy in children; vaccination to prevent varicella and immunization to prevent zoster; and the latest evidence linking VZV to GCA.

CONCLUSION

In children and adults, VZV is a common cause of stroke.

Ramsay Hunt Syndrome Associated with Central Nervous System Involvement in an Adult

Ramsay Hunt syndrome associated with varicella zoster virus reactivation affecting the central nervous system is rare. We describe a 55-year-old diabetic female who presented with gait ataxia, right peripheral facial palsy, and painful vesicular lesions involving her right ear. Later, she developed dysmetria, fluctuating diplopia, and dysarthria. Varicella zoster virus was detected in the cerebrospinal fluid by polymerase chain reaction. She was diagnosed with Ramsay Hunt syndrome associated with spread to the central nervous system. Her facial palsy completely resolved within 48 hours of treatment with intravenous acyclovir 10 mg/kg every 8 hours. However, cerebellar symptoms did not improve until a tapering course of steroid therapy was initiated.

High-Resolution Vessel Wall Magnetic Resonance Imaging in Varicella-Zoster Virus Vasculitis

Varicella-zoster virus vasculopathy is a rare but potentially treatable condition. Diagnosis has been based on angiography, brain magnetic resonance imaging (MRI), and cerebrospinal fluid analysis. High-resolution vessel wall MRI may aid to the diagnosis by differentiating inflammation from other vessel wall pathologies. We present the characteristic MRI findings of this condition in a young patient presenting with ischemic stroke.

CNS infections in patients with hematological disorders (including allogeneic stem-cell transplantation)-Guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

Diagnosis of CNS infections remains a great challenge in patients with hematological disorders since symptoms might both be masked and be mimicked by other conditions such as metabolic disturbances or consequences from antineoplastic treatment. Thus, awareness of this complication is crucial and any suspicion of a CNS infection should lead to timely and adequate diagnostics and treatment to improve the outcome in this population.

Infections of the central nervous system (CNS) are infrequently diagnosed in immunocompetent patients, but they do occur in a significant proportion of patients with hematological disorders. In particular, patients undergoing allogeneic hematopoietic stem-cell transplantation carry a high risk for CNS infections of up to 15%. Fungi and Toxoplasma gondii are the predominant causative agents. The diagnosis of CNS infections is based on neuroimaging, cerebrospinal fluid examination and biopsy of suspicious lesions in selected patients. However, identification of CNS infections in immunocompromised patients could represent a major challenge since metabolic disturbances, side-effects of antineoplastic or immunosuppressive drugs and CNS involvement of the underlying hematological disorder may mimic symptoms of a CNS infection. The prognosis of CNS infections is generally poor in these patients, albeit the introduction of novel substances (e.g. voriconazole) has improved the outcome in distinct patient subgroups. This guideline has been developed by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) with the contribution of a panel of 14 experts certified in internal medicine, hematology/oncology, infectious diseases, intensive care, neurology and neuroradiology. Grades of recommendation and levels of evidence were categorized by using novel criteria, as recently published by the European Society of Clinical Microbiology and Infectious Diseases.

Varicella Zoster Virus Infection in Granulomatous Arteritis of the Aorta

Granulomatous arteritis characterizes the pathology of giant cell arteritis, granulomatous aortitis, and intracerebral varicella zoster virus (VZV) vasculopathy. Because intracerebral VZV vasculopathy and giant cell arteritis are strongly associated with productive VZV infection in cerebral and temporal arteries, respectively, we evaluated human aortas for VZV antigen and VZV DNA. Using 3 different anti-VZV antibodies, we identified VZV antigen in 11 of 11 aortas with pathologically verified granulomatous arteritis, in 1 of 1 cases of nongranulomatous arteritis, and in 5 of 18 control aortas (28%) obtained at autopsy. The presence of VZV antigen in granulomatous aortitis was highly significant (P = .0001) as compared to control aortas, in which VZV antigen was never associated with pathology, indicating subclinical reactivation. VZV DNA was found in most aortas containing VZV antigen. The frequent clinical, radiological, and pathological aortic involvement in patients with giant cell arteritis correlates with the significant detection of VZV in granulomatous aortitis.

Embolic Strokes of Unknown Source and Cryptogenic Stroke: Implications in Clinical Practice

Up to a third of strokes are rendered cryptogenic or of undetermined etiology. This number is specifically higher in younger patients. At times, inadequate diagnostic workups, multiple causes, or an under-recognized etiology contributes to this statistic. Embolic stroke of undetermined source, a new clinical entity particularly refers to patients with embolic stroke for whom the etiology of embolism remains unidentified despite through investigations ruling out established cardiac and vascular sources. In this article, we review current classification and discuss important clinical considerations in these patients; highlighting cardiac arrhythmias and structural abnormalities, patent foramen ovale, paradoxical sources, and potentially under-recognized, vascular, inflammatory, autoimmune, and hematologic sources in relation to clinical practice.

Acute encephalitis in the immunocompromised individual

PURPOSE OF REVIEW

This article describes recent advances in the diagnosis and management of encephalitis in immunocompromised individuals.

RECENT FINDINGS

Herpes simplex virus (HSV) and varicella zoster virus (VZV) are common causes of encephalitis in immunocompromised individuals, although clinical manifestations may be atypical, and thus challenging to recognize. Recently, an increased incidence of HSV and VZV central nervous system infections has been reported in association with novel immunosuppressive and immunomodulatory treatments. The free-living ameba Balamuthia mandrillaris causes granulomatous encephalitis predominantly in immunocompromised individuals and is associated with nearly uniform fatality. In the setting of organ transplantation, the recipient's immunocompromised state along with the potential for donor-transmitted infections can result in a unique epidemiology of encephalitis, including infection by human herpes virus-6 and BK virus. Recent studies utilizing next-generation sequencing techniques have identified several pathogens, including Leptospira santarosai and a neurotropic astrovirus, as causes of encephalitis in immunocompromised individuals.

SUMMARY

Diagnosis and management of encephalitis is challenging in immunocompromised individuals, in part because of atypical clinical presentations and the presence of uncommon or novel infectious agents. Unbiased techniques for pathogen discovery are likely to play an increasing role in the diagnosis of central nervous system infections in immunocompromised individuals.

Genotyping of clinical varicella-zoster virus isolates collected from Yunnan in Southwestern China

Varicella-zoster virus (VZV) belongs to the α-herpesvirus family. Genetically, it is stable and is divided into several genotypes based upon the genetic variations. The genotypes of VZV are rarely studied in the Southwestern region of China. In the present study, the common genetic variations in the VZV genes were examined in 42 VZV isolates collected from the patients with herpes zoster in the Yunnan province (Southwestern China). The restriction fragment length polymorphism analysis of open reading frames (ORFs) 38, 54 and 62 in the VZV genes showed that all the collected VZV isolates were PstI, BglI and SmaI positive. The R5 variable-repeat region in these isolates was variable (R5A: 46.4%; R5B: 53.6%). The sequencing data of ORFs 1, 21, 22 and 54 indicated that 41 of the 42 collected VZV isolates could be grouped into genotype J or J1. Only one VZV isolate was identified as genotype A1 or M2. No new substitutions in the sequenced fragments were found in the collected VZV isolates. The results of the present study provided a preliminary genetic characterization of the VZV strains in the Yunnan province of Southwestern China.

Developments in Varicella Zoster Virus Vasculopathy

Varicella zoster virus (VZV) is a highly neurotropic human herpesvirus. Primary infection usually causes varicella (chicken pox), after which virus becomes latent in ganglionic neurons along the entire neuraxis. VZV reactivation results in zoster (shingles) which is frequently complicated by chronic pain (postherpetic neuralgia). VZV reactivation also causes meningoencephalitis, myelitis, ocular disorders, and vasculopathy, all of which can occur in the absence of rash. This review focuses on the association of VZV and stroke, and on the widening spectrum of disorders produced by VZV vasculopathy in immunocompetent and immunocompromised individuals, including recipients of varicella vaccine. Aside from ischemic stroke, VZV infection of cerebral arteries may lead to development of intracerebral aneurysms, with or without hemorrhage. Moreover, recent clinical-virological case reports and retrospective pathological-virological analyses of temporal arteries positive or negative for giant cell arteritis (GCA) indicate that extracranial VZV vasculopathy triggers the immunopathology of GCA. While many patients with GCA improve after corticosteroid treatment, prolonged corticosteroid use may potentiate VZV infection, leading to fatal vasculopathy in the brain and other organs.

Herpesvirus Infections and Childhood Arterial Ischemic Stroke: Results of the VIPS Study

BACKGROUND

Epidemiological studies demonstrate that childhood infections, including varicella zoster virus, are associated with an increased risk of arterial ischemic stroke (AIS). Other herpesviruses have been linked to childhood AIS in case reports. We sought to determine whether herpesvirus infections, which are potentially treatable, increase the risk of childhood AIS.

METHODS AND RESULTS

We enrolled 326 centrally confirmed cases of AIS and 115 stroke-free controls with trauma (29 days to 18 years of age) with acute blood samples (≤3 weeks after stroke/trauma); cases had convalescent samples (7-28 days later) when feasible. Samples were tested by commercial enzyme-linked immunosorbent assay kits for immunoglobulin M/immunoglobulin G antibodies to herpes simplex virus 1 and 2, cytomegalovirus, Epstein-Barr virus, and varicella zoster virus. An algorithm developed a priori classified serological evidence of past and acute herpesvirus infection as dichotomous variables. The median (quartiles) age was 7.7 (3.1-14.3) years for cases and 10.7 (6.9-13.2) years for controls (P=0.03). Serological evidence of past infection did not differ between cases and controls. However, serological evidence of acute herpesvirus infection doubled the odds of childhood AIS, even after adjusting for age, race, and socioeconomic status (odds ratio, 2.2; 95% confidence interval, 1.2-4.0; P=0.007). Among 187 cases with acute and convalescent blood samples, 85 (45%) showed evidence of acute herpesvirus infection; herpes simplex virus 1 was found most often. Most infections were asymptomatic.

CONCLUSIONS

Herpesviruses may act as a trigger for childhood AIS, even if the infection is subclinical. Antivirals like acyclovir might have a role in the prevention of recurrent stroke if further studies confirm a causal relationship.

Acute longitudinal and hemorrhagic myelitis caused by varicella-zoster virus in an immunocompetent adolescent

OBJECTIVES

In immunocompetent person, varicella-zoster virus (VZV)-induced myelitis is rare and the lesion usually comprise focal spinal cord segment. VZV-induced hemorrhagic myelitis with lesions comprising longitudinal spinal cord has never been reported.

METHODS

We report a 15-year-old male patient who developed acute flaccid quadriplegia, days after a common cold. One week after the quadriplegia developed, he presented a typical herpes zoster on the lateral side of his left waist.

RESULTS

IgG antibody for VZV was detected in cerebrospinal fluid and the spinal cord magnetic resonance imaging findings were consistent with that of small vessel vasculitis. Treatment with acyclovir and corticosteroids resulted in no significant clinical improvement.

CONCLUSIONS

In this report, we wanted to emphasize the hemorrhage, the extensiveness of inflammatory changes induced by VZV in spinal cord. It is suggested that VZV should be considered as a possible cause of a severe hemorrhagic myelitis even in immunocompetent adolescent.

Varicella-Zoster Virus Vasculopathy: A Case Report Demonstrating Vasculitis using Black-Blood MRI

Infections are rare but important causes of stroke. Among these, varicella zoster virus has been known to cause ischemic stroke. During an attack of herpes zoster ophthalmicus, it has been hypothesized that the virus replicates in the trigeminal ganglion and travels via the trigeminal nerve centrally to cause cerebral vasculopathy. Here we present a case of a 69 year-old Caucasian immunocompromised woman who suffered recurrent ischemic infarcts within the same vascular distribution following an episode of zoster ophthalmicus three months prior. An imaging technique termed black-blood magnetic resonance imaging was utilized to aid in the diagnosis of cerebral vasculitis. The case is used to provide a literature review of the pathogenesis, diagnosis, and treatment of cerebral varicella zoster vasculopathy. In situations where an isolated unilateral cerebral vasculopathy is identified, neurologists are urged to consider varicella zoster as a treatable etiologic agent, as untreated vasculopathy can lead to further strokes.

Varicella Zoster Virus in the Nervous System

Varicella zoster virus (VZV) is a ubiquitous, exclusively human alphaherpesvirus. Primary infection usually results in varicella (chickenpox), after which VZV becomes latent in ganglionic neurons along the entire neuraxis. As VZV-specific cell-mediated immunity declines in elderly and immunocompromised individuals, VZV reactivates and causes herpes zoster (shingles), frequently complicated by postherpetic neuralgia. VZV reactivation also produces multiple serious neurological and ocular diseases, such as cranial nerve palsies, meningoencephalitis, myelopathy, and VZV vasculopathy, including giant cell arteritis, with or without associated rash. Herein, we review the clinical, laboratory, imaging, and pathological features of neurological complications of VZV reactivation as well as diagnostic tests to verify VZV infection of the nervous system. Updates on the physical state of VZV DNA and viral gene expression in latently infected ganglia, neuronal, and primate models to study varicella pathogenesis and immunity are presented along with innovations in the immunization of elderly individuals to prevent VZV reactivation.

Zeroing in on zoster: A tale of many disorders produced by one virus

While herpes zoster infection has been recognized since antiquity, chickenpox (varicella) was confused with smallpox until the 1800s, when both illnesses became better understood. In the 20th century, varicella zoster virus (VZV) was shown to cause varicella upon primary (first-time) infection and herpes zoster (shingles) after reactivation of latent VZV. Scientific progress over the past 50 years has rapidly advanced the understanding and prevention of disease produced by VZV. Combined imaging and virological studies continue to reveal the protean neurological, ocular and visceral disorders produced by VZV.

Varicella zoster virus rhombencephalomyelitis following radiation therapy for oropharyngeal carcinoma

We report a 64-year-old man with a history of stage IV oropharyngeal squamous cell carcinoma treated with cisplatin and cetuximab followed by radiation therapy who developed a rapidly advancing rhombencephalomyelitis 11 months after the completion of radiation to the base of his tongue. His initial symptoms were left ear paresthesias, dysphagia, and progressive descending weakness. Routine cerebrospinal fluid (CSF) analysis was unremarkable. Initial MRI of the brain and cervical spinal cord revealed a demarcated symmetrical heterogeneously enhancing intramedullary lesion involving the cervicomedullary spinal cord. Progressive neurological worsening included increasing weakness of his limbs, facial weakness and ocular motility disorders and MRI revealed that the lesion was advancing into his pons and cervical spinal cord. Empiric treatment for radiation myelitis was initiated. Although CSF polymerase chain reaction was negative for varicella zoster virus (VZV), antibody studies revealed intrathecal synthesis of antibody to VZV and treatment for VZV was started as well. Improvement was slow and incomplete with subsequent worsening resulting in death in 5.5 weeks. The diagnosis of rhombencephalitis and myelitis following radiation therapy may be exquisitely challenging. The possibility of VZV, a treatable disorder, should be included in the differential diagnosis.

Multiple strokes associated with herpes simplex virus type-2 infection: case report

Herpes simplex virus (HSV) type-2 is known to cause meningitis and usually runs a benign course. Association of such infection with vasculitis of the central nervous system is not well known. Presented here is a case initially diagnosed as aseptic meningitis that subsequently evolved as stroke and exhibited angiographic evidence of widespread vasculitis of the intracranial vessels in association with a positive polymerase chain reaction (PCR) for HSV-2 in the cerebrospinal fluid (CSF).

Infection, vaccination, and childhood arterial ischemic stroke: Results of the VIPS study

OBJECTIVES

Minor infection can trigger adult arterial ischemic stroke (AIS) and is common in childhood. We tested the hypotheses that infection transiently increases risk of AIS in children, regardless of stroke subtype, while vaccination against infection is protective.

METHODS

The Vascular Effects of Infection in Pediatric Stroke study is an international case-control study that prospectively enrolled 355 centrally confirmed cases of AIS (29 days-18 years old) and 354 stroke-free controls. To determine prior exposure to infections and vaccines, we conducted parental interviews and chart review.

RESULTS

Median (interquartile range) age was 7.6 years for cases and 9.3 for controls (p = 0.44). Infection in the week prior to stroke, or interview date for controls, was reported in 18% of cases, vs 3% of controls, conferring a 6.3-fold increased risk of AIS (p < 0.0001); upper respiratory infections were most common. Prevalence of preceding infection was similar across stroke subtypes: arteriopathic, cardioembolic, and idiopathic. Use of vasoactive cold medications was similarly low in both groups. Children with some/few/no routine vaccinations were at higher stroke risk than those receiving all or most (odds ratio [OR] 7.3, p = 0.0002). In an age-adjusted multivariate logistic regression model, independent risk factors for AIS included infection in the prior week (OR 6.3, p < 0.0001), undervaccination (OR 8.2, p = 0.0004), black race (compared to white; OR 1.9, p = 0.009), and rural residence (compared to urban; OR 3.0, p = 0.0003).

CONCLUSIONS

Infection may act as a trigger for childhood AIS, while routine vaccinations appear protective. Hence, efforts to reduce the spread of common infections might help prevent stroke in children.

Varicella zoster virus infection

Infection with varicella zoster virus (VZV) causes varicella (chickenpox), which can be severe in immunocompromised individuals, infants and adults. Primary infection is followed by latency in ganglionic neurons. During this period, no virus particles are produced and no obvious neuronal damage occurs. Reactivation of the virus leads to virus replication, which causes zoster (shingles) in tissues innervated by the involved neurons, inflammation and cell death - a process that can lead to persistent radicular pain (postherpetic neuralgia). The pathogenesis of postherpetic neuralgia is unknown and it is difficult to treat. Furthermore, other zoster complications can develop, including myelitis, cranial nerve palsies, meningitis, stroke (vasculopathy), retinitis, and gastroenterological infections such as ulcers, pancreatitis and hepatitis. VZV is the only human herpesvirus for which highly effective vaccines are available. After varicella or vaccination, both wild-type and vaccine-type VZV establish latency, and long-term immunity to varicella develops. However, immunity does not protect against reactivation. Thus, two vaccines are used: one to prevent varicella and one to prevent zoster. In this Primer we discuss the pathogenesis, diagnosis, treatment, and prevention of VZV infections, with an emphasis on the molecular events that regulate these diseases. For an illustrated summary of this Primer, visit: http://go.nature.com/14xVI1.

[A long-term follow up of right ophthalmoplegia and severe right middle cerebral artery stenosis with right herpes zoster ophthalmics: a case report]

Here we report a case of a 68-year-old man with severe stenosis of the right middle cerebral artery (MCA) following herpes zoster ophthalmicus. He presented with right-sided ptosis and ophthalmoplegia 2 months after herpes zoster ophthalmicus. Cerebrospinal fluid (CSF) analysis revealed monocytosis, increased protein levels, and positivity for herpes zoster virus immunoglobulin M (IgM). Brain magnetic resonance imaging (MRI) revealed a small asymptomatic infarct in the right basal ganglia and severe stenosis of the right MCA (M1 segment). One month later, he presented with muscle weakness of the fingers of the left hand. Repeat CSF analysis revealed similar abnormalities to the previous analysis, and MRI showed a new small infarct in the right-sided motor area corresponding to the left fingers. He was treated with acyclovir (750 mg/day), prednisolone (1 mg/kg/day), and aspirin (100 mg/day). O2-gas positron emission tomography (PET) revealed decreased cerebral blood flow (CBF) after acetazolamide injection and normal cerebral vascular reactivity (CVR). He was on continuous treatment with prednisolone and aspirin for 1 year. The muscle weakness of the fingers of the left hand and right-sided ophthalmoplegia improved, and magnetic resonance angiography revealed considerable decrease in the stenosis of the right middle cerebral artery. CBF before and after acetazolamide injection and CVR on O2-gas PET also normalized. These results suggested that long-term treatment may prevent subsequent infarcts following herpes zoster ophthalmics.

Advances in primary angiitis of the central nervous system

Primary angiitis of the central nervous system (PACNS) is a rare idiopathic inflammatory syndrome targeting the vessels of the brain and spinal cord. Clinical presentation is variable, insidious, and non-specific; headache and encephalopathy are the most common symptoms. Multiple strokes affecting numerous vascular territories may be seen, and both focal and diffuse neurologic dysfunction may be present. Cerebrospinal fluid (CSF) analysis is crucial; a normal CSF along with normal brain parenchymal imaging carries a high negative predictive value in excluding PACNS. The role of imaging continues to evolve, and most patients have abnormal vascular imaging; however, the specificity of imaging for PACNS has historically been poor. Cerebral and meningeal biopsy is a valuable tool in confirming the diagnosis and excluding mimics. PACNS generally responds to immunosuppressive therapy. Failure to respond should prompt evaluation for an alternative diagnosis. Given the rarity of this disorder, exclusion of mimics such as the reversible cerebral vasoconstriction syndromes (RCVS) and infectious processes is essential.

Frosted branch angiitis caused by Varicella Zoster virus in an immunocompetent patient

INTRODUCTION

Frosted branch angiitis(FBA) is a panuveitis with sheating of all retinal vesssels.

CASE PRESENTATION

Herein we report an immunocompetent person who presented with fever, headache, atypical rash, and hazy vision. Ophthalmoscopy of both eyes revealed perivascular sheathing with frosted branch angiitis pattern in veins, patchy retinal hemorrhages. Aqueous PCR analysis turned positive for VZV.

DISCUSSION

This case illustrates that VZV should be considered in the differential diagnosis of retinal perivasculitis. Since a rapid and accurate diagnosis is crucial for prompt administration of antiviral therapy, PCR-based analysis of aqueous humor is a valuable tool for detecting viruses.

The relationship between herpes zoster and stroke

Varicella zoster virus (VZV) infects >95 % of the world population. Typically, varicella (chickenpox) results from primary infection. The virus then becomes latent in ganglionic neurons along the entire neuraxis. In immunocompromised individuals, VZV reactivates and causes herpes zoster (shingles), pain, and rash in 1-2 dermatomes. Multiple case reports showed a link between stroke and zoster, and recent studies have emerged which reveal that VZV infection of the cerebral arteries directly causes pathological vascular remodeling and stroke (VZV vasculopathy). In the past few years, several large epidemiological studies in Taiwan, Denmark, and the U.K. demonstrated that zoster is a risk factor for stroke and that antiviral therapy may reduce this risk. Herein, the history, clinical features, and putative mechanisms of VZV vasculopathy, as well as recent epidemiological studies demonstrating that zoster increases the risk of stroke, are discussed.

High-resolution MRI vessel wall imaging in varicella zoster virus vasculopathy

Contrast-enhanced vessel wall imaging high-resolution MRI (HRMR) has revealed vessel wall thickening and enhancement in multiple intracranial vasculopathies, including varicella zoster virus (VZV) vasculopathy. We retrospectively reviewed a database of patients with virologically-verified VZV vasculopathy, who underwent initial and follow-up HRMR between April 2011 and May 2014. Six patients were identified. Baseline demographic and clinical characteristics were collected, including stroke risk factors, history of VZV-related disorders, neurological presentation, course and antiviral treatment. Initial HRMR in patients with VZV vasculopathy demonstrated various patterns of stenosis, vessel wall thickening and enhancement, predominantly in terminal internal carotid artery segments and the M1 segment of the middle cerebral arteries. Follow-up HRMR showed improvement of stenosis, with reduced vessel wall thickening and enhancement at multiple times after treatment. HRMR has the potential to assist in diagnosis and treatment of VZV vasculopathy.

Clinical benefits of routine varicella vaccination for adults

Varicella is a highly contagious disease caused by varicella zoster virus. In children, it is generally a mild to moderate illness while it is often more severe in adults, with serious complications as dehydration, pneumonia, bleeding problems, infection or inflammation of the brain, secondary bacterial infections, sepsis, toxic shock syndrome, bone infections, joint infections and deaths. Some groups of adults are at major risk of complications, in particular immunocompromised persons as subjects with impaired humoral immunity and who is receiving systemic steroids, persons who live or work in environments in which transmission of varicella is likely, health-care personnel and pregnant women. After the introduction of Universal Mass Vaccination (UMV), the first mathematical models suggested that vaccination will lead to a shift in the average age at infection from children to adults with an increasing numbers of complicated forms, nevertheless new models predicted that, although an upward shift in the age at infection may occur, the overall morbidity due to varicella is likely to decrease. Current literature seems to suggest that for public health authorities the key action to prevent an increase of varicella incidence among adults is to achieve high vaccination coverage among babies and adolescents in countries who adopted UMV.