Varicella zoster virus vasculopathies: diverse clinical manifestations, laboratory features, pathogenesis, and treatment

Mass-spectrometric profiling of cerebrospinal fluid reveals metabolite biomarkers for CNS involvement in varicella zoster virus reactivation

Background

Varicella zoster virus (VZV) reactivation spans the spectrum from uncomplicated segmental herpes zoster to life-threatening disseminated CNS infection. Moreover, in the absence of a small animal model for this human pathogen, studies of pathogenesis at the organismal level depend on analysis of human biosamples. Changes in cerebrospinal fluid (CSF) metabolites may reflect critical aspects of host responses and end-organ damage in neuroinfection and neuroinflammation. We therefore applied a targeted metabolomics screen of CSF to three clinically distinct forms of VZV reactivation and infectious and non-infectious disease controls in order to identify biomarkers for CNS involvement in VZV reactivation.

Methods

Metabolite profiles were determined by targeted liquid chromatography-mass spectrometry in CSF from patients with segmental zoster (shingles, n = 14), facial nerve zoster (n = 16), VZV meningitis/encephalitis (n = 15), enteroviral meningitis (n = 10), idiopathic Bell’s palsy (n = 11), and normal pressure hydrocephalus (n = 15).

Results

Concentrations of 88 metabolites passing quality assessment clearly separated the three VZV reactivation forms from each other and from the non-infected samples. Internal cross-validation identified four metabolites (SM C16:1, glycine, lysoPC a C26:1, PC ae C34:0) that were particularly associated with VZV meningoencephalitis. SM(OH) C14:1 accurately distinguished facial nerve zoster from Bell’s palsy. Random forest construction revealed even more accurate classifiers (signatures comprising 2–4 metabolites) for most comparisons. Some of the most accurate biomarkers correlated only weakly with CSF leukocyte count, indicating that they do not merely reflect recruitment of inflammatory cells but, rather, specific pathophysiological mechanisms. Across all samples, only the sum of hexoses and the amino acids arginine, serine, and tryptophan correlated negatively with leukocyte count. Increased expression of the metabolites associated with VZV meningoencephalitis could be linked to processes relating to neuroinflammation/immune activation, neuronal signaling, and cell stress, turnover, and death (e.g., autophagy and apoptosis), suggesting that these metabolites might sense processes relating to end-organ damage.

Conclusions

The results provide proof-of-concept for the value of CSF metabolites as (1) disease-associated signatures suggesting pathophysiological mechanisms, (2) degree and nature of neuroinflammation, and (3) biomarkers for diagnosis and risk stratification of VZV reactivation and, likely, neuroinfections due to other pathogens.

Trial registration

Not applicable (non-interventional study).

Electronic supplementary material

The online version of this article (10.1186/s12974-017-1041-0) contains supplementary material, which is available to authorized users.

HIV infection and stroke

The landscape of human immunodeficiency virus (HIV) infection is changing with the increasing coverage of antiretroviral therapy (ART). Patients are living longer but continually exposed to a virologically suppressed HIV infection. This has resulted in a decrease in acquired immune deficiency syndrome (AIDS)-related complications such as opportunistic infections, and an increase in non-AIDS complications such as stroke. In this era, stroke is perhaps the most important neurologic complication of HIV infection. Furthermore, stroke is more of a heterogeneous disease in people living with HIV infection and therefore needs to be approached systematically. Many of the etiologies are treatable. HIV-associated vasculopathy is perhaps the most common etiology in this population and our understanding of this is still evolving. Moreover, the treatment of HIV infection may contribute to an excess risk of stroke and interact with stroke therapies.

Infections of the Nervous System

Microorganisms can affect the entire neuraxis, producing a variety of neurologic complications that frequently entail prolonged hospitalizations and complicated treatment regimens. The spread of pathogens to new regions and the reemergence of opportunistic organisms in immunocompromised patients pose increasing challenges to health care professionals. Because rapid diagnosis and treatment may prevent long-term neurologic sequelae, providers should approach these diseases with a structured, neuroanatomic framework, incorporating a thorough history, examination, laboratory analysis, and neuroimaging in their clinical reasoning and decision-making.

Increased risk of dementia following herpes zoster ophthalmicus

This retrospective cohort study aimed to examine the relationship between herpes zoster ophthalmicus (HZO) and the subsequent risk of dementia using a population-based database. We retrieved the study sample from the Taiwan Longitudinal Health Insurance Database 2005. The study group included 846 patients with HZO, and the comparison group included 2538 patients without HZO. Each patient was individually followed for a 5-year period to identify those patients who subsequently received a diagnosis of dementia. We performed a Cox proportional hazards regression to calculate the hazard ratios (HRs) along with 95% confidence intervals (CIs) for dementia during the follow-up period between patients with HZO and comparison patients. The respective incidence rates of dementia per 1000 person-years were 10.15 (95% CI: 7.22~13.87) and 3.61 (95% CI: 2.61~4.89) for patients with HZO and comparison patients. The Cox proportional analysis showed that the crude HR of dementia during the 5-year follow-up period was 2.83 (95% CI: 1.83–4.37) for patients with HZO than comparison patients. After adjusting for patients’ characteristics and comorbidities, HZO patients were still at a 2.97-fold greater risk than comparison patients for developing dementia. Furthermore, we found that of sampled male patients, the crude HR of dementia for patients with HZO was as high as 3.35 (95% CI = 1.79–6.28) compared to comparison patients. This study demonstrated an association between HZO and dementia. Clinicians must be alert to suspect dementia in patients with cognitive impairment who had prior HZO.

Risk of Stroke/Transient Ischemic Attack or Myocardial Infarction with Herpes Zoster: A Systematic Review and Meta-Analysis

BACKGROUND

Accumulating evidence indicates that herpes zoster (HZ) may increase the risk of stroke/transient ischemic attack (TIA) or myocardial infarction (MI), but the results are inconsistent. We aim to explore the relationship between HZ and risk of stroke/TIA or MI and between herpes zoster ophthalmicus (HZO) and stroke.

METHODS

We estimated the relative risk (RR) and 95% confidence intervals (CIs) with the meta-analysis. Cochran's Q test and Higgins I² statistic were used to check for heterogeneity.

RESULTS

HZ infection was significantly associated with increased risk of stroke/TIA (RR = 1.30, 95% CI: 1.17-1.46) or MI (RR = 1.18, 95% CI: 1.07-1.30). The risk of stroke after HZO was 1.91 (95% CI 1.32-2.76), higher than that after HZ. Subgroup analyses revealed increased risk of ischemic stroke after HZ infection but not hemorrhagic stroke. The risk of stroke was increased more at 1 month after HZ infection than at 1-3 months, with a gradual reduced risk with time. The risk of stroke after HZ infection was greater with age less than 40 years than 40-59 years and more than 60 years. Risk of stroke with HZ infection was greater without treatment than with treatment and was greater in Asia than Europe and America but did not differ by sex.

CONCLUSIONS

Our study indicated that HZ infection was associated with increased risk of stroke/TIA or MI, and HZO infection was the most marked risk factor for stroke. Further studies are needed to explore whether zoster vaccination could reduce the risk of stoke/TIA or MI.

A systematic review and meta-analysis on herpes zoster and the risk of cardiac and cerebrovascular events

Background

Patients who develop herpes zoster or herpes zoster ophthalmicus may be at risk for cerebrovascular and cardiac complications. We systematically reviewed the published literature to determine the association between herpes zoster and its subtypes with the occurrence of cerebrovascular and cardiac events.

Methods/Results

Systematic searches of PubMed (MEDLINE), SCOPUS (Embase) and Google Scholar were performed in December 2016. Eligible studies were cohort, case-control, and self-controlled case-series examining the association between herpes zoster or subtypes of herpes zoster with the occurrence of cerebrovascular and cardiac events including stroke, transient ischemic attack, coronary heart disease, and myocardial infarction. Data on the occurrence of the examined events were abstracted. Odds ratios and their accompanying confidence intervals were estimated using random and fixed effects models with statistical heterogeneity estimated with the I² statistic. Twelve studies examining 7.9 million patients up to 28 years after the onset of herpes zoster met our pre-defined eligibility criteria. Random and fixed effects meta-analyses showed that herpes zoster, type unspecified, and herpes zoster ophthalmicus were associated with a significantly increased risk of cerebrovascular events, without any evidence of statistical heterogeneity. Our meta-analysis also found a significantly increased risk of cardiac events associated with herpes zoster, type unspecified.

Conclusions

Our results are consistent with the accumulating body of evidence that herpes zoster and herpes zoster ophthalmicus are significantly associated with cerebrovascular and cardiovascular events.

A Simplified Approach to Encephalitis and Its Mimics: Key Clinical Decision Points in the Setting of Specific Imaging Abnormalities

RATIONALE AND OBJECTIVES

Infectious encephalitis is a relatively common cause of morbidity and mortality. Treatment of infectious encephalitis with antiviral medication can be highly effective when administered promptly. Clinical mimics of encephalitis arise from a broad range of pathologic processes, including toxic, metabolic, neoplastic, autoimmune, and cardiovascular etiologies. These mimics need to be rapidly differentiated from infectious encephalitis to appropriately manage the correct etiology; however, the many overlapping signs of these various entities present a challenge to accurate diagnosis. A systematic approach that considers both the clinical manifestations and the imaging findings of infectious encephalitis and its mimics can contribute to more accurate and timely diagnosis.

MATERIALS AND METHODS

Following an institutional review board approval, a health insurance portability and accountability act (HIPAA)-compliant search of our institutional imaging database (teaching files) was conducted to generate a list of adult and pediatric patients who presented between January 1, 1995 and October 10, 2013 for imaging to evaluate possible cases of encephalitis. Pertinent medical records, including clinical notes as well as surgical and pathology reports, were reviewed and correlated with imaging findings. Clinical and imaging findings were combined to generate useful flowcharts designed to assist in distinguishing infectious encephalitis from its mimics. Key imaging features were reviewed and were placed in the context of the provided flowcharts.

RESULTS

Four flowcharts were presented based on the primary anatomic site of imaging abnormality: group 1: temporal lobe; group 2: cerebral cortex; group 3: deep gray matter; and group 4: white matter. An approach that combines features on clinical presentation was then detailed. Imaging examples were used to demonstrate similarities and key differences.

CONCLUSIONS

Early recognition of infectious encephalitis is critical, but can be quite complex due to diverse pathologies and overlapping features. Synthesis of both the clinical and imaging features of infectious encephalitis and its mimics is critical to a timely and accurate diagnosis. The use of the flowcharts presented in this article can further enable both clinicians and radiologists to more confidently differentiate encephalitis from its mimics and improve patient care.

Diplopia as isolated presentation of varicella zoster central nervous system reactivation

Here, we report a patient who developed diplopia secondary to a right cranial nerve III and IV palsy, as well as fever and headache. Cerebrospinal fluid analysis (CSF) showed high varicella-zoster virus (VZV)-DNA viral load (>300,000,000 copies/ml). VZV antibodies in CSF was ≥1:16. Diagnosis of neurological reactivation of VZV infection was made without the presence of characteristic vesicular rash. Quantitative real-time PCR for VZV and intrathecal dosage of VZV IgM and IgG should be performed in cases suspected for viral encephalitis and also in all patients with not otherwise attributable cranial nerve lesions.

Management of Viral Central Nervous System Infections: A Primer for Clinicians

Viruses are a common cause of central nervous system (CNS) infections with many host, agent, and environmental factors influencing the expression of viral diseases. Viruses can be responsible for CNS disease through a variety of mechanisms including direct infection and replication within the CNS resulting in encephalitis, infection limited to the meninges, or immune-related processes such as acute disseminated encephalomyelitis. Common pathogens including herpes simplex virus, varicella zoster, and enterovirus are responsible for the greatest number of cases in immunocompetent hosts. Other herpes viruses (eg, cytomegalovirus, John Cunningham virus) are more common in immunocompromised hosts. Arboviruses such as Japanese encephalitis virus and Zika virus are important pathogens globally, but the prevalence varies significantly by geographic region and often season. Early diagnosis from radiographic evidence and molecular (eg, rapid) diagnostics is important for targeted therapy. Antivirals may be used effectively against some pathogens, although several viruses have no effective treatment. This article provides a review of epidemiology, diagnostics, and management of common viral pathogens in CNS disease.

Disarming Cellular Alarm Systems-Manipulation of Stress-Induced NKG2D Ligands by Human Herpesviruses

The coevolution of viruses and their hosts led to the repeated emergence of cellular alert signals and viral strategies to counteract them. The herpesvirus family of viruses displays the most sophisticated repertoire of immune escape mechanisms enabling infected cells to evade immune recognition and thereby maintain infection. The herpesvirus family consists of nine viruses that are capable of infecting humans: herpes simplex virus 1 and 2 (HSV-1, HSV-2), varicella zoster virus (VZV), Epstein–Barr virus (EBV), human cytomegalovirus (HCMV), roseoloviruses (HHV-6A, HHV-6B, and HHV-7), and Kaposi’s-sarcoma-associated herpesvirus (KSHV). Most of these viruses are highly prevalent and infect a vast majority of the human population worldwide. Notably, research over the past 15 years has revealed that cellular ligands for the activating receptor natural-killer group 2, member D (NKG2D)—which is primarily expressed on natural killer (NK) cells—are common targets suppressed during viral infection, i.e., their surface expression is reduced in virtually all lytic herpesvirus infections by diverse mechanisms. Here, we review the viral mechanisms by which all herpesviruses known to date to downmodulate the expression of the NKG2D ligands. Also, in light of recent findings, we speculate about the importance of the emergence of eight different NKG2D ligands in humans and further allelic diversification during host and virus coevolution.

Varicella vasculopathy presenting with thunderclap headache

Our report serves to highlight Varicella vasculopathy as a rarity not to be overlooked in the differential diagnosis of subarachnoid haemorrhage.

Management of adult infectious encephalitis in metropolitan France

Infectious encephalitis is a severe disease leading to a high mortality and morbidity. The most frequent causes include Herpes simplex virus, Varicella Zoster virus, Listeria monocytogenes, and Mycobacterium tuberculosis. Urgent treatment is required (anti-infective therapy and nonspecific supportive care). The aim of this study was to define treatment strategy, empirical and after microbiological documentation at 48hours, through a systematic literature review.

Infectious encephalitis: Management without etiological diagnosis 48hours after onset

Introduction

The etiological diagnosis of infectious encephalitis is often not established 48 hours after onset. We aimed to review existing literature data before providing management guidelines.

Method

We performed a literature search on PubMed using filters such as “since 01/01/2000”, “human”, “adults”, “English or French”, and “clinical trial/review/guidelines”. We also used the Mesh search terms “encephalitis/therapy” and “encephalitis/diagnosis”.

Results

With Mesh search terms “encephalitis/therapy” and “encephalitis/diagnosis”, we retrieved 223 and 258 articles, respectively. With search terms “encephalitis and corticosteroid”, we identified 38 articles, and with “encephalitis and doxycycline” without the above-mentioned filters we identified 85 articles. A total of 210 articles were included in the analysis.

Discussion

Etiological investigations must focus on recent travels, animal exposures, age, immunodeficiency, neurological damage characteristics, and potential extra-neurological signs. The interest of a diagnosis of encephalitis for which there is no specific treatment is also to discontinue any empirical treatments initially prescribed. Physicians must consider and search for autoimmune encephalitis.

MR imaging of adult acute infectious encephalitis

BACKGROUND

Imaging is a key tool for the diagnosis of acute encephalitis. Brain CT scan must be urgently performed to rule out a brain lesion with mass effect that would contraindicate lumbar puncture. Brain MRI is less accessible than CT scan, but can provide crucial information with patients presenting with acute encephalitis.

METHOD

We performed a literature review on PubMed on April 1, 2015 with the search terms "MRI" and "encephalitis".

RESULTS

We first described the various brain MRI abnormalities associated with each pathogen of acute encephalitis (HSV, VZV, other viral agents targeting immunocompromised patients or travelers; tuberculosis, listeriosis, other less frequent bacterial agents). Then, we identified specific patterns of brain MRI abnomalies that may suggest a particular pathogen. Limbic encephalitis is highly suggestive of HSV; it also occurs less frequently in encephalitis due to HHV6, syphillis, Whipple's disease and HIV primary infection. Rhombencephalitis is suggestive of tuberculosis and listeriosis. Acute ischemic lesions can occur in patients presenting with severe bacterial encephalitis, tuberculosis, VZV encephalitis, syphilis, and fungal infections.

CONCLUSION

Brain MRI plays a crucial role in the diagnosis of acute encephalitis. It detects brain signal changes that reinforce the clinical suspicion of encephalitis, especially when the causative agent is not identified by lumbar puncture; it can suggest a particular pathogen based on the pattern of brain abnormalities and it rules out important differential diagnosis (vascular, tumoral or inflammatory causes).

Stroke Associated With Varicella Zoster Vasculopathy: A Clinicoradiological Profile of 3 Patients

INTRODUCTION

Varicella zoster (VZ) vasculopathy is a rare but well recognized cause of stroke. In the absence of zoster rash and infection in remote past, the disease can pose diagnostic challenge. We report 3 cases of anterior circulation stroke occurring in close temporal relation to VZ. Their clinical, radiologic, and angiographic features are discussed.

CASE REPORT

Of the 3 patients, 2 had stroke within a span of 4 to 6 weeks of herpes zoster ophthalmicus while the third patient had zoster of cervical dermatome. Magnetic resonance imaging revealed acute subcortical infarcts in 2, while 1 patient showed acute on chronic infarct in left middle cerebral artery territory. The magnetic resonance angiography was abnormal in 2 patients while it was normal in third. All the patients were treated with acyclovir and antiplatelets with good recovery in 2.

CONCLUSIONS

VZ associated vasculopathy may have diverse clinical profile and neuroimaging features. It should be considered as an important and treatable cause of stroke in appropriate clinical settings.

[Juvenile stroke - what is important?]

Stroke in young adults is a diagnostic and therapeutic challenge for all persons involved. Approximately 15% of ischemic strokes occur in young adults. Lack of awareness of the symptoms in emergency departments often results in delayed diagnosis and access to specific therapeutic options, such as revascularization. The causes are often heterogeneous and necessitate specific investigations. The etiology of juvenile stroke includes drug abuse, vasculitis and arteriopathies, such as reversible vasoconstriction syndrome and posterior reversible encephalopathy syndrome, although the prevalence of classical vascular risk factors is high. The most frequent causes of ischemic stroke in young adults are cardioembolism and microangiopathy; furthermore, dissection of vessels of the neck are more frequent compared to older patients. According to the results of currently available studies reperfusion strategies, such as intravenous fibrinolysis and mechanical thrombectomy are efficacious and safe in young patients.

Herpes zoster and the risk of ischemic and hemorrhagic stroke: A systematic review and meta-analysis

Background

Herpes zoster infection and stroke are highly prevalent in the general population; however, reports have presented inconsistent findings regarding the relationship between herpes zoster infection and stroke. In this meta-analysis, we aimed to clarify this association.

Material and methods

The PubMed and Embase databases were searched for studies published from their inception to January 2016. Two investigators independently extracted the data. The pooled relative risk (RR) was calculated using a random effects model.

Results

A total of 8 studies met the inclusion criteria. During the first 1 month after herpes zoster infection, the pooled RRs for ischemic stroke and hemorrhagic stroke were 1.55 (95% CI, 1.46–1.65) and 1.70 (95% CI, 0.73–3.96), respectively, and within 3 months after infection, the corresponding RRs were 1.17 (95% CI, 1.12–1.23) and 2.05 (95% CI, 1.17–3.60), respectively. At 1 year and more than 1 year after herpes zoster infection, a significant relationship was not observed between herpes zoster infection and the incidence of ischemic and hemorrhagic stroke. Publication bias was not observed.

Conclusion

The accumulated evidence generated from this systematic review indicates that an increased risk for ischemic stroke occurred in the short term after herpes zoster infection, whereas a significant relationship was not observed in the long term after infection. With respect to hemorrhagic stroke, the association was not significant. With respect to hemorrhagic stroke, the association between was not significant except within 3 months after a herpes zoster infection.

Herpes zoster and the search for an effective vaccine

Primary infection with varicella zoster virus (VZV), an exclusively human neurotrophic alphaherpsesvirus, results in varicella, known more commonly as chickenpox. Like other alphaherpesviruses, VZV establishes latency in the sensory ganglia and can reactivate to cause herpes zoster (also known as shingles), a painful and debilitating disease, especially in elderly and immunocompromised individuals. The overall incidence of herpes zoster in Europe and the United States is three per 1000 people, but increases sharply after 60 years of age to 10 per 1000 people. Zostavax® is a vaccine approved by the Federal Drug Administration for the prevention of herpes zoster. Unfortunately, this vaccine reduces the incidence of disease by only 51% and the incidence of post-herpetic neuralgia by 66·5% when administered to those aged 60 and older. Moreover, it is contraindicated for individuals who are immunocompromised or receiving immunosuppressant treatments, although they are at higher risk for herpes zoster compared to immune-competent older individuals. This paper reviews VZV pathogenesis, host responses and current vaccines available to prevent herpes zoster.

Exam 4 Questions

A 73-year-old male with a history of hypertension and hyperlipidemia is currently in the stroke unit after suffering a right middle cerebral artery infarct. His symptoms started 2 h prior to arrival at the hospital, and tPA was administered. The patient is plegic on the left side and with mild dysarthria, but is otherwise neurologically intact. His labwork is within normal limits. Which of the following describes the optimal deep venous thrombosis (DVT) prophylaxis regimen for this patient?A.

Wait 6 h post tPA, then administer unfractionated heparin (UFH) along with intermittent pneumatic compression (IPC)

B.

Wait 24 h post tPA, then administer UFH along with IPC

C.

Wait 6 h post tPA, then administer low molecular weight heparin (LMWH) along with IPC

D.

Wait 24 h post tPA, then administer LMWH along with IPC

E.

IPC only for the first 72 h, then LMWH or UFH after obtaining follow-up imaging

All of the following causes of acute encephalitis have the matching characteristic radiological features except:A.

Autoimmune limbic encephalitis: T2/FLAIR hyperintensity in the mesial temporal lobes

B.

Cytomegalovirus: T2/FLAIR hyperintensity in the subependymal white matter

C.

JC virus: T2/FLAIR hyperintensity in the parieto-occipital lobes and corpus callosum

D.

Herpes simplex virus type 1: restricted diffusion in frontal/temporal lobes and insular cortex

E.

Varicella zoster: T2/FLAIR hyperintensity in the brainstem

Which of the following categorizations is most accurate regarding acute respiratory distress syndrome (ARDS) in the setting of subarachnoid hemorrhage (SAH)?A.

Non-neurogenic, non-cardiogenic

B.

Neurogenic, non-cardiogenic

C.

Neurogenic, cardiogenic

D.

Non-neurogenic, cardiogenic

E.

None of the above accurately reflect ARDS in SAH

A 52-year-old female is admitted to the ICU with a Hunt-Hess 1, modified Fisher 2 subarachnoid hemorrhage. Her past medical history is significant for hypertension, diabetes mellitus, and chronic renal insufficiency. She undergoes craniotomy for surgical clipping of an anterior cerebral artery aneurysm, and does not experience any additional complications. Two weeks later, she begins complaining of left calf pain, and a lower extremity sonogram demonstrated a proximal deep venous thrombosis (DVT). The patient weighs 60 kg. Her laboratory values are as follows: sodium 142 mEq/L, potassium 3.4 mEq/L, carbon dioxide 18 mEq/L, blood urea nitrogen (BUN) 70 mg/dL, and serum creatinine 2.5 mg/dL. What would be the optimal treatment for this patient’s proximal DVT?A.

Unfractionated heparin infusion for at least 5 days concomitantly with warfarin therapy

B.

Low molecular weight heparin 60 mg twice a day for at least 5 days concomitantly with warfarin therapy

C.

Fondaparinux 7.5 mg daily for 5 days followed by warfarin therapy

D.

Apixaban 10 mg twice daily for 7 days followed by 5 mg twice daily

E.

Rivaroxaban 15 mg twice daily for 21 days followed by 20 mg once daily

All of the following are currently implicated in uremic encephalopathy except:A.

Derangements in cerebral metabolism

B.

Alterations in the blood-brain barrier

C.

Accumulation of circulating toxins

D.

Imbalance of endogenous neurotransmitters

E.

Recurrent lobar hemorrhages

A 70-year-old female is hospitalized with a recent ischemic infarct. As part of stroke core measures, you obtain a hemoglobin A1c of 10.0. What is an approximate estimation of this patient’s average blood glucose level over the last several months?A.

70 mg/dL

B.

100 mg/dL

C.

130 mg/dL

D.

190 mg/dL

E.

240 mg/dL

A 28-year-old female with no known past medical history is in the ICU in status epilepticus, with anti-N-methyl D-aspartate (NMDA) receptor antibodies isolated in the cerebrospinal fluid. Which of the following is most likely to identify the root cause of her illness?A.

Transvaginal ultrasound

B.

Contrast-enhanced CT of the chest

C.

Contrast-enhanced CT of the brain

D.

Virtual colonography

E.

Thorough examination of the skin, particularly in sun-exposed areas

A 17-year-old male with no significant past medical history collapses during a high school football game, and goes into cardiac arrest. He did not have any complaints earlier in the day. The patient is brought to a nearby hospital, where is he resuscitated, intubated, and transferred to the ICU for further management. The patient is currently undergoing therapeutic hypothermia, and a work-up is underway to determine the cause of his sudden collapse. Which of the following is the most likely diagnosis?A.

Rupture of a previously undiagnosed cerebral aneurysm

B.

Hypertrophic cardiomyopathy

C.

Commotio cordis

D.

Severe hyponatremia and cerebral edema

E.

Brugada syndrome

A 31-year-old female at 38 weeks gestation is currently hospitalized for the treatment of preeclampsia. Due to her medical condition, her obstetrician is currently considering induced labor. At which point will this patient no longer be at risk for developing frank seizure activity as a result of her condition?A.

48 h postpartum

B.

1 week after delivery

C.

2 weeks after delivery

D.

4 weeks after delivery

E.

6 weeks after delivery

A 38-year-old male with no prior medical history presents to the emergency department with fever and severe headaches for several days. A CT scan of the brain is unremarkable, and the results of a lumbar puncture are pending. What is the most appropriate empiric antimicrobial regimen at this time?A.

Cefazolin and vancomycin

B.

Ceftriaxone and vancomycin

C.

Ceftriaxone, vancomycin and ampicillin

D.

Piperacillin/tazobactam and vancomycin

E.

Meropenem and vancomycin

The majority of intramedullary spinal cord neoplasms are:A.

Astrocytomas

B.

Meningiomas

C.

Metastatic lesions

D.

Ependymomas

E.

Hemangioblastomas

Which of the following derived parameter formulas is correct?A.

Cardiac index = cardiac output x body surface area

B.

Stroke volume = cardiac output/heart rate

C.

Systemic vascular resistance = 80 × (mean arterial pressure/cardiac output)

D.

Pulmonary vascular resistance = 80 × (mean pulmonary artery pressure/cardiac output)

E.

All of the above are correct

A 23-year-old female marathon runner is currently in the ICU after suffering from heat stroke following an outdoor run on a particularly hot summer day. She was initially delirious in the emergency department, but progressed to coma and respiratory failure requiring mechanical ventilation. Her oral temperature is 42.1 °C. Which of the following would be most effective in reducing this patient’s severe hyperthermia?A.

Regularly scheduled alternating acetaminophen and ibuprofen

B.

Spraying room temperature water on the patient, followed by fanning

C.

Ice water immersion

D.

Dantrolene sodium, 2.5 mg/kg

E.

Application of ice packs to the groin and axilla

Hyperinsulinemia-euglycemia (HIE) therapy may be useful for toxicity related to which of the following?A.

Tricyclic antidepressants

B.

Calcium channel blockers

C.

Aspirin

D.

Digoxin

E.

Lithium

A 71-year-old female with a history of alcohol abuse is currently intubated in the ICU following a catastrophic spontaneous left basal ganglia hemorrhage with resultant herniation. You have just declared her brain dead. The patient’s family agrees to make her an organ donor, and the organ donation coordinator requests you initiate levothyroxine therapy. Which of the following benefits would be expected with this treatment?A.

Increase the number of solid organs available for transplant

B.

Eliminate the need for hepatic biopsy prior to liver transplant

C.

Eliminate the need for cardiac catheterization prior to heart transplant

D.

Eliminate the need for bronchoscopy prior to lung transplant

E.

Reduce the need for supplementation of sodium, potassium, calcium, and magnesium

Which of the following is not an element of the Full Outline of Unresponsiveness (FOUR) score?A.

Eye opening

B.

Respiratory function

C.

Brainstem reflexes

D.

Motor response

E.

Verbal response

A 23-year-old female is currently in the ICU with status asthmaticus. She was initially on noninvasive positive pressure ventilation, with an arterial blood gas (ABG) as follows: pH 7.13, pCO₂ 60 mmHg, PaO₂ is 61 mmHg, HCO₃ 24 mmol/L, and oxygen saturation of 90%. She is given continuous inhaled albuterol, intravenous steroids, and magnesium sulfate. She subsequently becomes more lethargic and is intubated, with settings as follows: volume assist-control, rate of 12 breaths/min, tidal volume of 500 cc, PEEP of 5 cm H₂O, and FiO₂ of 50%. Peak airway pressure is 50 cm H₂O and plateau pressure is 15 cm H₂O. A stat portable chest x-ray shows hyperinflation with no pneumothorax. A repeat ABG after 30 min of invasive ventilation shows the following: pH of 7.24, pCO₂ 49 mmHg, PaO₂ 71 mmHg, HCO₃ is 25 mmol/L. Which of the following should be performed next?A.

Increase rate to 16

B.

Increase tidal volume to 600 cc

C.

Initiate bicarbonate infusion

D.

Switch to pressure assist-control

E.

Maintain current settings

Which of the following mechanisms is implicated in super-refractory status epilepticus?A.

Influx of proinflammatory molecules

B.

Upregulation of NMDA receptors

C.

Upregulation of molecular transport molecules

D.

Downregulation of GABA receptors

E.

All of the above

A 85-year-old male with a history nephrolithiasis, mild dementia, and alcohol abuse presented to the emergency department after a fall from standing, and was found to a right holohemispheric subdural hematoma. His clot was evacuated successfully, in spite of his oozing diathesis in the operating room (INR on arrival was 1.4 with a platelet count of 88 × 10³/μL). His serum transaminases are twice the normal value, and he has had refractory chronic hyponatremia. He has had three convulsions during this week of hospitalization, in spite of levetiracetam therapy at 1.5 g twice a day. Over the past 24 h, he has had a marked increase in agitation. He has also just had a 5-s run of non-sustained ventricular tachycardia, and his systolic blood pressure is now 85 mmHg. You are considering discontinuing his levetiracetam and starting a new agent. Which of the following would be the best choice in this scenario?A.

Carbamazepine

B.

Phenytoin

C.

Valproate

D.

Lacosamide

E.

Topiramate

A 65-year-old male with a history of COPD on rescue albuterol and ipratropium is diagnosed with myasthenia gravis, and started on an acetylcholinesterase inhibitor. He returns several days later complaining of increased salivation and worsening bronchial secretions in the absence of fevers, purulent sputum, or increasing dyspnea. These symptoms are not relieved by use of his albuterol. On exam, he has slightly decreased air movement throughout both lung fields without any clear wheezing, no focal rales, and a normal inspiratory to expiratory ratio. Which treatment option is most likely to be beneficial?A.

Increase frequency of short-acting ß₂ agonist use

B.

Add a standing long-acting inhaled ß₂ agonist

C.

Add glycopyrrolate as needed

D.

Add inhaled corticosteroids

E.

Add oral systemic corticosteroids

Regarding states of impaired consciousness, which of the following statements regarding arousal and awareness is correct?A.

Coma: intact arousal, but impaired awareness

B.

Minimally conscious state: impaired arousal and impaired awareness

C.

Persistent vegetative state: intact arousal, but impaired awareness

D.

Locked-in state: intact arousal, but impaired awareness

E.

All of the above are correct

A 62-year-old female is currently in the ICU following craniotomy for clipping of a cerebral aneurysm. Postoperatively, she is noted to have an oxygen saturation of 92% on 50% non-rebreather face mask, and her respiratory rate is 32 breaths/min. She denies chest pain. Her blood pressure is 96/72 mmHg and heart rate is 120 beats/min. Nimodipine has been held according to blood pressure parameters. A portable chest x-ray shows hazy opacities bilaterally, and bedside echocardiogram shows decreased left ventricular systolic function with apical, septal, lateral, anterior, anteroseptal and inferolateral wall akinesis, along with apical ballooning. Which of the following should be performed next?A.

Intubate the patient and begin mechanical ventilation

B.

Call urgent cardiology consult for cardiac catheterization

C.

Start noninvasive positive airway pressure ventilation

D.

Administer broad spectrum antibiotics

E.

Administer albuterol and systemic corticosteroids

Which of the following is the most common etiology of acute spinal cord ischemia and infarction?A.

Atherosclerotic disease

B.

Rupture of an abdominal aortic aneurysm

C.

Degenerative spine disease

D.

Cardioembolic events

E.

Systemic hypotension in the setting of other disease processes

A 62-year-old female with a history of coronary artery disease has just been admitted to the ICU with a left-sided spontaneous basal ganglia hemorrhage. The patient takes 325 mg of aspirin daily at home, and you are considering platelet transfusion. Which of the following has been demonstrated regarding platelet transfusion in this setting?A.

Improved chances of survival to hospital discharge

B.

Decreased hospital length-of-stay

C.

Improved chances of survival at 3 months

D.

Improved modified Rankin scale at 3 months

E.

None of the above

Which of the following therapies has been shown to decrease the incidence of delayed cerebral ischemia (DCI) in the setting of subarachnoid hemorrhage (SAH)?A.

Atorvastatin

B.

Magnesium

C.

Methylprednisolone

D.

Nicardipine

E.

None of the above

A 70-year-old male with a history of diabetes, hypertension, and cigarette smoking (one pack per day for the last 40 years) is currently in the ICU with a COPD exacerbation. This is his third exacerbation this year, and was discharged from the hospital only 3 weeks prior. On your examination, he is alert, his breathing is labored, and he has rales at the right lung base. His vital signs are as follows: blood pressure 90/60 mmHg, heart rate 120 beats per minute, respirations 28 per minute, and temperature 38.3 °C. His oxygen saturation on 50% face mask is 93%, and his most recent PCO₂ is 55 mmHg. Labs are notable for the following: white blood cell count 14.4 × 10⁹/L with 90% neutrophils, blood urea nitrogen (BUN) 30 mg/dL, serum creatinine 1.2 mg/dL, and glucose 240 mg/dL. Ketones are negative. He is currently on noninvasive positive pressure ventilation at 10/5 cm H₂O and 50% FiO₂, and broad spectrum antibiotics have been administered. An hour later, the nurse pages you because his heart rate is now 140 beats per minute and irregular, blood pressure is 85 systolic, oxygen saturation is 85%, and he is minimally responsive. You now hear bilateral rales, most prominently in the right lung base, and scattered wheezes. Which of the following should be performed next?A.

Increase inspiratory pressure to 15 and FiO₂ to 100%

B.

Start a continuous diltiazem infusion and give intravenous furosemide

C.

Start a continuous phenylephrine infusion targeting a mean arterial pressure (MAP) > 65

D.

Give 125 mg of solumedrol and administer albuterol via nebulizer

E.

Intubate the patient and initiate mechanical ventilation

A 57-year-old male with a history of epilepsy is currently in the stroke unit following a large right middle cerebral artery infarction. A nasogastric tube has been inserted, and 24 h continuous enteral feeds have been initiated. The patient is currently on 100 mg of phenytoin every 8 h for seizure prophylaxis. Which of the following measures should be taken to prevent the patient from developing subtherapeutic phenytoin levels?A.

Change to 18 h tube feeds, and only administer phenytoin at night

B.

Change to 18 h tube feeds, and only administer phenytoin twice daily

C.

Switch from standard to hydrolyzed tube feeds

D.

Switch from standard to glycemic control tube feeds

E.

Hold tube feeds for 2 h before and after phenytoin administration

A 37-year-old female presents to the emergency department with approximately 2 weeks of progressively worsening clumsiness and drastic mood swings. Her past medical history is significant only for Crohn’s disease, for which she takes both natalizumab and infliximab. A contrast-enhanced CT scan of her head is performed, revealing hypodense, non-enhancing lesions in the cortical white matter of the frontal and parietal lobes. Despite treatment, the patient expires 1 month later. Which of the following is true regarding the most likely diagnosis?A.

The diagnosis may be confirmed via CSF analysis

B.

The pathologic process spares oligodendrocytes

C.

It is a prion-based disease

D.

The condition is universally fatal despite treatment

E.

All of the above

A 58-year-old female presents to the emergency department with dry cough, fever and rapidly progressive dyspnea over 1 week. She has a history of rheumatoid arthritis (RA) and is maintained on weekly methotrexate and daily prednisone (which was increased to 30 mg starting 1 month ago for an acute flare). She takes no other medications. Her vital signs are as follows: blood pressure 100/70 mmHg, heart rate 110 beats/min, respiratory rate 20 breaths/min, and temperature 38.0 °C. In the ED she develops progressive hypoxemia with oxygen saturation 92% on 100% nonrebreather, and is increasingly diaphoretic. She is emergently intubated, and a chest x-ray post intubation shows extensive bilateral lung opacities. Which of the following should be administered at this time?A.

Ceftriaxone and azithromycin

B.

Vancomycin and piperacillin-tazobactam

C.

Vancomycin, cefepime, and fluconzole

D.

Ceftriaxone, levofloxacin, and trimethoprim-sulfamethoxazole

E.

Tigecycline only

A 45-year-old woman undergoes uncomplicated transsphenoidal resection of a pituitary macroadenoma. She appears well hydrated and is not complaining of excessive thirst. Post-operatively, she is noted to have increased urine output. Serum sodium is 137 mEq/L, and serum osmolarity is 275 mOsm/kg. What is the most likely cause of her polyuria?A.

Syndrome of inappropriate antidiuretic hormone

B.

Diabetes insipidus

C.

Cerebral salt wasting

D.

Fluid mobilization

E.

All of the above are equally likely

A 36-year-old female with a recent lumbar puncture to rule out subarachnoid hemorrhage is now complaining of a severe headache unlike anything she has experienced previously. She reports her headache is worse when standing, and better upon lying flat. She is otherwise neurologically intact. All of the following medications may be beneficial in this scenario except:A.

Acetaminophen

B.

Ibuprofen

C.

Caffeine

D.

Aminophylline

E.

Methylprednisolone

Which of the following is the most common overall cause of acute myocardial infarction?A.

Coronary dissection

B.

Plaque rupture

C.

Imbalance between oxygen demand and supply across a fixed obstruction

D.

Coronary vasospasm

E.

Ischemia related to hypotension and decreased perfusion

A 78-year-old male is in the ICU recovering from sepsis and pneumonia. He was just recently extubated after 2 days of mechanical ventilation and sedation with a fentanyl infusion. Over the ensuing days, he develops worsening abdominal distention, poor bowel sounds, and no stool output. CT scan reveals significant colonic distention, but no mass or obstruction. Records demonstrate a normal routine colonoscopy performed 6 weeks ago. You have appropriately hydrated the patient, corrected any electrolyte abnormalities, placed a rectal tube, withheld all opiates, and given intravenous erythromycin, but to no avail. Abdominal x-rays continue to demonstrate marked cecal dilatation greater than 12 cm in diameter. What is the next best appropriate therapy for this patient?A.

Neostigmine

B.

Naloxone

C.

Metoclopromide

D.

Surgical consultation for hemicolectomy

E.

Endoscopic percutaneous cecostomy tube placement

Which of the following is the most common cerebral vascular malformation in the general population?A.

AV malformation

B.

Dural AV fistula

C.

Developmental venous anomaly

D.

Cavernous malformation

E.

Vein of Galen malformation

A 49-year-old female with a history of acute lymphoblastic leukemia and recent subcutaneous cerebrospinal fluid (CSF) reservoir placement presents to the emergency department with fever, chills, and increased confusion for the past 3 days. Her CSF reservoir was last accessed 1 week ago. A thorough work-up reveals no other obvious infectious source, and there is concern for CSF reservoir-associated meningitis. Which of the following is the most likely causative organism?A.

Coagulase-negative staphylococci

B.

Propionobacterium acnes

C.

Methicillin-resistant Staphylococcus aureus

D.

Klebsiella pneumoniae

E.

Neisseria meningitidis

A 47-year-old woman presents to the emergency department with headache, nausea, and vomiting. Non-contrast head CT is performed, revealing subarachnoid blood in the right Sylvian fissure, and conventional angiography reveals the presents of a large right-sided MCA aneurysm. The patient undergoes successful surgical clipping of her aneurysm, and is being observed in the ICU. On admission, the patient’s serum sodium was 142 mEq/L and the hematocrit was 37%; by the seventh post-operative day, the serum sodium is 127 mEq/L and the hematocrit is 44%. Bedside ultrasonography demonstrates an IVC diameter of approximately 0.9 cm. Which of the following interventions would be least reasonable at this time?A.

Fludrocortisone, 0.2 mg twice a day

B.

2% hypertonic saline, infused peripherally

C.

3% hypertonic saline, infused centrally

D.

Sodium chloride oral tablets

E.

1500 mL daily fluid restriction

Which of the following is true regarding central (non-infectious) fever?A.

Less common in subarachnoid hemorrhage

B.

More common versus infectious fever

C.

Earlier onset versus infectious fever

D.

Easier to confirm versus infectious fever

E.

All of the above

Flaccid paralysis is most commonly associated with which of the following forms of encephalitis?A.

West Nile

B.

Varicella zoster

C.

Rabies

D.

Herpes simplex

E.

Epstein-Barr

Which of the following would not be considered appropriate therapy for heparin-induced thrombocytopenia (HIT)?A.

Discontinuation of heparin products alone

B.

Danaparoid

C.

Fondaparinux

D.

Argatroban

E.

All of the above are acceptable treatment options

A 45-year-old male with severe blunt traumatic brain injury (TBI) from a motor vehicle collision suffered a ventricular fibrillation cardiac arrest at the time of injury with return of spontaneous circulation (ROSC) in the field after endotracheal intubation and one dose of epinephrine. On arrival to the emergency department, no regional wall motion abnormalities were noted on surface echocardiography and no ST segment changes were seen on the presenting EKG. Head CT revealed cerebral contusions but no extra-axial mass lesions. The patient is now in the ICU and found to be comatose without sedation. Mild therapeutic hypothermia to 33° is being considered in the management of this post-arrest patient. Which of the following statements is true?A.

Mild therapeutic hypothermia is contraindicated due to the risk of induced epilepsy

B.

Mild therapeutic hypothermia is contraindicated with any intracranial pathology on CT imaging

C.

Mild therapeutic hypothermia does not induce a clinically significant coagulopathy

D.

Patients who have sustained ROSC after an arrest associated with TBI do not benefit from therapeutic hypothermia

E.

Endovascular cooling is superior to surface cooling in young patients with ROSC

A 35-year-old male is in the intensive care unit following resection of a large right-sided meningioma. He is currently intubated and sedated on a continuous fentanyl infusion. The nurse calls you to the bedside due to concerns over “unusual ventilator waveforms”. Upon arrival, you note the following (see Image 1). What is the best way to describe this phenomenon?A.

Reverse triggering

B.

Double triggering

C.

Breath stacking

D.

Missed triggering

E.

None of the above; normal ventilator waveforms are present

Dysregulated Glycoprotein B-Mediated Cell-Cell Fusion Disrupts Varicella-Zoster Virus and Host Gene Transcription during Infection

The highly conserved herpesvirus glycoprotein complex gB/gH-gL mediates membrane fusion during virion entry and cell-cell fusion. Varicella-zoster virus (VZV) characteristically forms multinucleated cells, or syncytia, during the infection of human tissues, but little is known about this process. The cytoplasmic domain of VZV gB (gBcyt) has been implicated in cell-cell fusion regulation because a gB[Y881F] substitution causes hyperfusion. gBcyt regulation is necessary for VZV pathogenesis, as the hyperfusogenic mutant gB[Y881F] is severely attenuated in human skin xenografts. In this study, gBcyt-regulated fusion was investigated by comparing melanoma cells infected with wild-type-like VZV or hyperfusogenic mutants. The gB[Y881F] mutant exhibited dramatically accelerated syncytium formation in melanoma cells caused by fusion of infected cells with many uninfected cells, increased cytoskeleton reorganization, and rapid displacement of nuclei to dense central structures compared to pOka using live-cell confocal microscopy. VZV and human transcriptomes were concurrently investigated using whole transcriptome sequencing (RNA-seq) to identify viral and cellular responses induced when gBcyt regulation was disrupted by the gB[Y881F] substitution. The expression of four vital VZV genes, ORF61 and the genes for glycoproteins gC, gE, and gI, was significantly reduced at 36 h postinfection for the hyperfusogenic mutants. Importantly, hierarchical clustering demonstrated an association of differential gene expression with dysregulated gBcyt-mediated fusion. A subset of Ras GTPase genes linked to membrane remodeling were upregulated in cells infected with the hyperfusogenic mutants. These data implicate gBcyt in the regulation of gB fusion function that, if unmodulated, triggers cellular processes leading to hyperfusion that attenuates VZV infection.

IMPORTANCE

The highly infectious, human-restricted pathogen varicella-zoster virus (VZV) causes chickenpox and shingles. Postherpetic neuralgia (PHN) is a common complication of shingles that manifests as prolonged excruciating pain, which has proven difficult to treat. The formation of fused multinucleated cells in ganglia might be associated with this condition. An effective vaccine against VZV is available but not recommended for immunocompromised individuals, highlighting the need for new therapies. This study investigated the viral and cellular responses to hyperfusion, a condition where the usual constraints of cell membranes are overcome and cells form multinucleated cells. This process hinders VZV and is regulated by a viral glycoprotein, gB. A combination of live-cell imaging and next-generation genomics revealed an alteration in viral and cellular responses during hyperfusion that was caused by the loss of gB regulation. These studies reveal mechanisms central to VZV pathogenesis, potentially leading to improved therapies.

Intracranial vessel wall imaging for evaluation of steno-occlusive diseases and intracranial aneurysms

Cerebrovascular diseases have traditionally been classified, diagnosed and managed based on their luminal characteristics. However, over the past several years, several advancements in MRI techniques have ushered in high-resolution vessel wall imaging (HR-VWI), enabling evaluation of intracranial vessel wall pathology. These advancements now allow us to differentiate diseases which have a common angiographic appearance but vastly different natural histories (i.e. moyamoya versus atherosclerosis, reversible cerebral vasoconstriction syndrome versus vasculitis, stable versus unstable intracranial aneurysms). In this review, we detail the anatomical, histopathological and imaging characteristics of various intracranial steno-occlusive diseases and types of intracranial aneurysms and describe the role that HR-VWI can play in diagnosis, risk stratification and treatment.

The Short- and Long-Term Risk of Stroke after Herpes Zoster: A Meta-Analysis

Background

Accumulating evidence indicates that stroke risk may be increased following herpes zoster. The aim of this study is to perform a meta-analysis of current literature to systematically analyze and quantitatively estimate the short and long-term effects of herpes zoster on the risk of stroke.

Methods

Embase, PubMed and Cochrane library databases were searched for relevant studies up to March 2016. Studies were selected for analysis based on certain inclusion and exclusion criteria. Relative risks with 95% confidence interval (CI) were extracted to assess the association between herpes zoster and stroke.

Results

A total of 8 articles were included in our analysis. The present meta-analysis showed that the risks of stroke after herpes zoster were 2.36 (95% CI: 2.17–2.56) for first 2 weeks, 1.56 (95% CI: 1.46–1.66) for first month, 1.17 (95% CI: 1.13–1.22) for first year, and 1.09 (95% CI: 1.02–1.16) for more than 1 year, respectively.

Conclusion

The results of our study demonstrated that herpes zoster was associated with a higher risk of stroke, but the risks decreased along with the time after herpes zoster.

Meningitis with polymerase chain reaction for varicella zoster positivity in cerebrospinal flid of a young immunocompetent adult

Meningitis caused by varicella zoster virus (VZV) is quite rare among young immunocompetent adults though immunocompromised patients are often seen to be affected by reactivation of VZV presenting with primary clinical features of dermatomal rashes and neurological sequelae. Here, we report the clinical scenario of a young, healthy male who had presented with fever, headache, and onset of dermatomal rashes later than the fever and was eventually diagnosed to be a case of VZV meningitis. We would like to highlight the fact that even young immunocompetent patients though rarely, might contract VZV meningitis and clinicians should have a high index of suspicion and keen eyes to catch the more obvious features of VZV infection on complete physical examination and must not harbor any reservations in ordering polymerase chain reaction for VZV DNA or initiating aggressive antiviral therapy.

Cerebrospinal fluid viral load and biomarkers of neuronal and glial cells in Ramsay Hunt syndrome

Reactivation of varicella zoster virus (VZV) can manifest with facial palsy diagnosed as Ramsay Hunt Syndrome (RHS) or Ramsay Hunt Syndrome zoster sine herpete (RHS-ZSH). These syndromes are associated with poor prognosis despite treatment with antivirals and corticosteroids. Concentrations of biomarkers such as neurofilament protein (NFL), S-100β protein and glial fibrillary acidic protein (GFAp) have previously been measured in cerebrospinal fluid (CSF) to assess neuronal damage and glial pathology. We employed immunochemical methods to measure concentrations of NFL, S-100β protein and GFAp in CSF from patients with RHS (n = 15) and RHS-ZSH (n = 13) diagnosed by detection of VZV DNA in the CSF by quantitative PCR, and compared with a control group (n = 52). The biomarker concentrations were correlated with CSF viral load and outcome measured by House-Brackmann score. NFL and GFAp concentrations were increased compared with controls (P = 0.008 and P = 0.04), while S-100β levels were decreased. This pattern was more pronounced in patients with RHS compared to the patients with RHS-ZSH (NS and P = 0.028). The amount of viral DNA in CSF correlated with increased GFAp (P = 0.003) and NFL (P = 0.006). No correlations were found between biomarker concentrations and patient outcome. Patients with facial palsy caused by VZV had biochemical signs of neuronal damage and astrogliosis. High amounts of viral DNA may be associated with the degree of damage on neuronal and astroglial cells. Prospective studies are warranted to elucidate the association of elevated biomarkers in the CSF and outcome assessed by more sensitive tests.

Laboratory Diagnosis of Central Nervous System Infection

Central nervous system (CNS) infections are potentially life threatening if not diagnosed and treated early. The initial clinical presentations of many CNS infections are non-specific, making a definitive etiologic diagnosis challenging. Nucleic acid in vitro amplification-based molecular methods are increasingly being applied for routine microbial detection. These methods are a vast improvement over conventional techniques with the advantage of rapid turnaround and higher sensitivity and specificity. Additionally, molecular methods performed on cerebrospinal fluid samples are considered the new gold standard for diagnosis of CNS infection caused by pathogens, which are otherwise difficult to detect. Commercial diagnostic platforms offer various monoplex and multiplex PCR assays for convenient testing of targets that cause similar clinical illness. Pan-omic molecular platforms possess potential for use in this area. Although molecular methods are predicted to be widely used in diagnosing and monitoring CNS infections, results generated by these methods need to be carefully interpreted in combination with clinical findings. This review summarizes the currently available armamentarium of molecular assays for diagnosis of central nervous system infections, their application, and future approaches.

The Clinical Approach to Encephalitis

Encephalitis has various etiologies, but viral infections and autoimmune disorders are the most commonly identified. Clinical signs, geographical clues, and diagnostic testing-including cerebrospinal fluid abnormalities and magnetic resonance imaging abnormalities-can be helpful in identifying the cause. Certain forms of encephalitis have specific treatments; hence, establishing a diagnosis rapidly and accurately is crucial. Here, we describe the clinical approach to diagnosing several common etiologies of encephalitis as well as treatment strategies.

Clinical interpretation of high-resolution vessel wall MRI of intracranial arterial diseases

Intracranial arterial pathology has traditionally been evaluated with luminal imaging. Recently, high-resolution vessel wall imaging (HR-VWI) with MRI has facilitated submillimetre evaluation of the arterial walls. This technique can help differentiate various causes of intracranial steno-occlusive disease, identify culprit atherosclerotic plaques with a recent cerebral infarct, locate vessel wall pathology in areas with minimal or no narrowing on luminal imaging, predict aneurysm stability and identify a ruptured aneurysm when multiple aneurysms are present. Interpretation of HR-VWI examinations requires a solid understanding of the pathophysiology, clinical features, serum and cerebrospinal fluid laboratory findings, treatment administered and fundamental patterns of VWI abnormalities that may be encountered with the intracranial vasculopathies. This pictorial essay aimed to illustrate the essential findings of common conditions encountered with HR-VWI including intracranial atherosclerosis, moyamoya disease, intracranial vasculitis, varicella zoster vasculopathy, reversible cerebral vasoconstriction syndrome and aneurysms.

Identification of an indol-based derivative as potent and selective varicella zoster virus (VZV) inhibitor

We report the synthesis and antiviral activity of a new family of non-nucleoside antivirals, derived from the indole nucleus. Modifications of this template through Mannich and Friedel-Crafts reactions, coupled with nucleophilic displacement and reductive aminations led to 23 final derivatives, which were pharmacologically tested. Tryptamine derivative 17a was found to have a selective inhibitory activity against human varicella zoster virus (VZV) replication in vitro, being inactive against a variety of other DNA and RNA viruses. A structure-activity relationship (SAR) study showed that the presence of a biphenyl ethyl moiety and the acetylation at the amino group of tryptamine are a prerequisite for anti-VZV activity. The novel compound shows the same activity against thymidine kinase (TK)-competent (TK⁺) and TK-deficient (TK⁻) VZV strains, pointing to a novel mechanism of antiviral action.

•

A library of indole-based derivatives has been designed and synthesized as potential antiviral agents.

•

Friedel-Crafts and Mannich reactions were used for the synthesis of different indole derivatives.

•

Tryptamine derivative 17a displays significant inhibitory activity against VZV replication.

•

A mechanism of action independent from the virus-encoded thymidine kinase is suggested.

ADULT WITH CHICKENPOX COMPLICATED BY SYSTEMIC VASCULITIS AND BILATERAL RETINAL VASCULITIS WITH RETINAL VASCULAR OCCLUSIONS

PURPOSE

To describe an adult with chickenpox resulting in systemic vasculitis and bilateral retinal vascular occlusions.

METHODS

Single case report.

RESULTS

A 58-year-old man with chickenpox complicated by disseminated varicella-zoster systemic and retinal vasculitis resulting in a combined arterial and venous occlusion in one eye with multiple branch retinal vein occlusions in the other eye. There was no evidence of retinitis. The patient systemically improved after treatment with acyclovir and steroids; however, his vision remained poor.

CONCLUSION

Chickenpox can be associated with systemic vasculopathy and may rarely result in multiple systemic and ocular infarcts, including severe retinal vascular occlusions.

Herpes zoster of gingiva in an older woman: a rare case report

OBJECTIVE

The aim of the article is to highlight the distinguishing features of secondary varicella gingival infection in an older women.

BACKGROUND

Herpes zoster is an acute sporadic, painful viral infection in older people caused by the reactivation of the latent varicella zoster virus. Herpes zoster affecting the gingiva without any dermal lesions is a rare pathological condition that mimics many intraoral vesiculobullous lesions. The ambiguous nature of this condition creates a diagnostic dilemma.

MATERIALS AND METHODS

A 58-year-old woman presented with an acute, unilateral and persistent burning sensation and pain in the gingiva with desqaumating vesicullobulous lesion.

RESULTS

The women was diagnosed with secondary varicella zoster infection.

CONCLUSION

Herpes zoster of the gingiva could manifest as painful desquamative vesicular lesions, pulpal or other painful neuralgic condition in older individuals which need careful diagnosis before formulating appropiate treatment plan.

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.

Relapsing CD8+ encephalitis-looking for a solution

CD8+ encephalitis (CD8+E) is an emerging and incompletely understood HIV-associated neurological syndrome, typically presenting as a steroid-responsive subacute encephalopathy with prominent white matter changes in patients with apparently well-controlled HIV infection. Some cases can be associated with the phenomenon of 'viral escape' (disproportionate replication within the cerebrospinal fluid), but the most important pathophysiology of CD8+E is thought to involve an attack on HIV-infected CD4+ lymphocytes by autoreactive CD8+ cells. We report a case of CD8+E where the initial positive response to steroid treatment was followed by several relapses on withdrawal. This led to the use of mycophenolate mofetil (MMF) as a long-term steroid-sparing agent, which is the first time this approach has been reported in the literature. The patient has now been on treatment with MMF for 10 months and it has been possible to taper the steroids down to a minimal maintenance dose without further relapse.

Varicella-zoster virus (VZV) DNA in serum of patients with VZV central nervous system infections

OBJECTIVES

Varicella-zoster virus (VZV) is a common viral agent causing central nervous system (CNS) infections, normally diagnosed by detection of VZV DNA in cerebrospinal fluid (CSF). Our aim was to investigate trends in VZV DNAemia in VZV CNS infections, which could potentially contribute to diagnosis and secondly, correlate the amount of VZV DNA in serum to severity of disease.

METHODS

Seventy-two patients with VZV CNS infections diagnosed by detection of VZV DNA in CSF and concomitant neurological symptoms were included. The amount of VZV DNA was measured by real-time PCR in paired serum and CSF samples and compared to a control group of herpes zoster (n = 36).

RESULTS

An increased amount of VZV DNA was detected in serum in patients with encephalitis compared to patients with meningitis or Ramsay-Hunt syndrome, respectively (p = 0.003 and p = 0.024). A greater proportion of patients with VZV CNS infections and detectable VZV DNA in serum had ongoing rash compared to those without detectable VZV DNA in serum (p ≤ 0.001). The viral load in serum of patients with neurological symptoms was lower compared to in patients with herpes zoster without neurological symptoms (p ≤ 0.001) and only 32/72 of the patients with VZV CNS disease had VZV DNA detected in serum.

CONCLUSION

Increased amount of VZV DNA in serum of patients with VZV CNS infections seems associated with encephalitis and ongoing rash. Additionally, viral DNA analysis by PCR in serum may be a helpful diagnostic tool although viral DNA analysis by PCR in CSF is the method of choice for diagnosis.

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.

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.

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.

Risk of stroke and transient ischaemic attack after herpes zoster

We assessed the association of herpes zoster (HZ) with stroke/transient ischaemic attack (TIA) in the general population according to age with controlling risk factors for stroke, using a nationwide representative cohort. The study was based on a prospective dynamic cohort consisting of 1 million Koreans representing all age groups, genders and geographical areas in the Korea Health Insurance Database. New events of stroke/TIA and HZ were identified using the diagnostic codes in the International Classification of Diseases, tenth revision. The risk for stroke/TIA after HZ was compared with HZ-free stroke/TIA individuals according to age group. A total of 766 179 adults were followed up for 11 years from 2003. The incidence of the first-diagnosed HZ cases was 9.40 per 1000 person-years, and that of the first-diagnosed stroke/TIA cases was 9.77 per 1000 person-years. The risk for stroke/TIA was higher in patients who had previous HZ episodes than in those who had never experienced HZ (incidence rate ratio 1.90; 95% CI 1.85-1.95). In addition, this risk persisted for several years after HZ. The risk of stroke/TIA after HZ gradually decreased with age; adjusted hazard ratio (HR) 2.04 in 18- to 30-year-olds, HR 1.74 in 30- to 40-year-olds, HR 1.43 in 40- to 50-year-olds, HR 1.23 in 50- to 60-year-olds, HR 1.24 in 60- to 70-year-olds, and HR 1.29 in those >70 years old, after controlling risk factors for stroke/TIA. Our findings provide evidence that HZ carries an increased risk of stroke or TIA and that the effect of HZ on stroke decreases with increasing age.

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.

Decreased risk of intracerebral hemorrhage among patients with milder allergic rhinitis

BACKGROUND

This study investigated whether allergic rhinitis (AR) increases the risk of intracerebral hemorrhage (ICH).

METHODS

Using Taiwanese insurance outpatient claims data, 52,870 patients with new diagnoses of AR between 2000 and 2010 were identified, and 105,680 age- and sex-frequency matched people without AR were chosen randomly as controls. Risks of ICH were correlated with AR and comorbidities, such as diabetes, hypertension, coronary artery disease, hyperlipidemia, disease and chronic kidney disease, and were estimated by the end of 2011.

RESULTS

The risk of ICH was lower in the AR cohort than in the comparison cohort, with an adjusted hazard ratio (aHR) of 0.58 (95% confidence interval [CI] = 0.50-0.66), assessed using the multivariable Cox model. Age-specific analysis demonstrated that the aHR for ICH in the AR patients increased with age, with an aHR of 0.53 (95% CI = 0.39-0.71) in the ≤49-year age group, which increased to 0.72 (95% CI = 0.59-0.89) in the elderly age group. The risk of ICH increased with the severity of AR, from an aHR of 0.47 (95% CI = 0.40-0.56) in mild AR patients to 2.55 (95% CI = 1.88-3.47) in severe ones. For patients without comorbidities, the risk of ICH was 0.46 times (95% CI = 0.34-0.63) lower in the AR cohort than in the comparison cohort.

CONCLUSION

This study showed for the first time that milder AR is correlated with a reduction in the risk of ICH, particularly for elderly patients.

Association Between Reduced Risk of Intracerebral Hemorrhage and Pelvic Inflammatory Disease

This study examines whether pelvic inflammatory disease (PID) facilitates the development of intracerebral hemorrhage (ICH).By using outpatient claims data from the National Health Insurance Research Database (NHIRD) of Taiwan, we included the data of 25,508 patients who were newly diagnosed with PID between 1999 and 2004, and also from the Taiwan NHIRD, we randomly selected 102,032 women without PID, who were frequency-matched by age and entry-year and with 4 times the number of the PID patients, as the control cohort. We measured ICH risks associated with PID and comorbidities, including hyperlipidemia, diabetes, hypertension, ischemic heart disease, and atrial fibrillation, by the end of 2011.In comparison with the controls, the ICH hazard was less in the PID group with an adjusted hazard ratio (aHR) of 0.67 (95% confidence interval [CI]:0.50-0.90), which was noted by calculation with the Cox proportional regression model. The ICH risk in the PID patients reduced progressively with the advance of age, with aHRs of 0.75 (95% CI:0.41-1.39) and 0.50 (95% CI:0.29-0.88), respectively, in the age <35-year and age ≥50-year groups. ICH risk lowered gradually with the progress of PID severity, from mild PID with an aHR of 0.72 (95% CI:0.53-0.98) to severe PID with that of 0.30 (95% CI:0.10-0.92). PID patients without any comorbidites had lower ICH risk (aHR = 0.63, 95% CI:0.42-0.94) than the controls without any comorbidites did.Our findings revealed that PID is associated with reduced ICH development, especially for older patients.