Features of varicella zoster virus myelitis and dependence on immune status

Bacterial and Viral Infectious Disease of the Spine

Spinal infections are a diverse group of diseases affecting different compartments of the spine with variable clinical and imaging presentations. Diagnosis of spinal infections is based on a combination of clinical features, laboratory markers, and imaging studies. Imaging plays a pivotal role in the diagnosis and management of spinal infections. The characteristic imaging manifestations of bacterial and viral infections in the spine are discussed with key teaching points emphasized.

Global Immunization Crisis Amid the COVID-19 Pandemic: Implications for Pediatric Oncology

Declining herd immunity and severe manifestation of vaccine preventable infections underscores the need for vaccinations campaigns to urgently vaccinate children who missed their routine immunizations.

Varicella-Zoster Meningitis and Myelitis After Herpes Zoster Dermatitis Treatment With Amenamevir: A Case Series and Literature Review

Varicella-zoster virus (VZV), known for causing chickenpox, establishes latent infections in neural tissues. Reactivation of VZV can lead to herpes zoster (HZ) and various neurological complications. In this report, we present four cases of VZV meningitis and myelitis following amenamevir treatment for HZ dermatitis with positive VZV DNA in cerebrospinal fluid (CSF) revealed by polymerase chain reaction (PCR). Three of them were considered immunocompromised hosts given the fact that two of these patients were taking immunosuppressive drugs for rheumatoid arthritis, and one patient had a history of sigmoid colon cancer (four months after resection). After HZ onset, amenamevir, which has poor CSF transfer, was prescribed for all the patients, and all of them developed central nervous complications by VZV (meningitis in three cases and myelitis in one case) confirmed by PCR. All the patients were treated with acyclovir, which has a higher CSF transfer, and fully recovered. We speculate that amenamevir might have failed to prevent VZV infection in the central nervous system (CNS) and think that consideration should be given to administering acyclovir in preference to amenamevir for ΗΖ patients at high risk of CNS VZV infection, such as immunocompromised hosts.

[Transverse myelitis and cauda equina syndrome followed by varicella in a patient with varicella-zoster virus infection]

A 74-year-old man was admitted to our hospital with complaints of weakness in the lower extremities, urinary retention for 10 days, and generalized vesicular rash for 7 days. Spinal magnetic resonance imaging showed contrast enhancement at the Th12-L1 level of the spinal cord and cauda equina. Serum and cerebrospinal fluid varicella-zoster virus (VZV)-immunoglobulin (Ig) G antibody titers were markedly elevated, and VZV-IgM was detected in cerebrospinal fluid. The patient was diagnosed with VZV transverse myelitis and cauda equina syndrome with subsequent varicella and was treated with acyclovir and prednisolone. Two months later, muscle weakness, and dysuria had almost completely resolved. We hypothesize that latent VZV in the ganglia reactivated and caused transverse myelitis, which subsequently spread to the body via the bloodstream, resulting in the development of varicella.

Clinical features of varicella-zoster virus caused neurological diseases detected by metagenomic next-generation sequencing

Clinical presentation of central nervous system (CNS) infections caused by varicella-zoster virus (VZV) is highly sophisticated, making identification challenging. We retrospectively reported 18 cases of VZV neurologic disease confirmed by metagenomic next-generation sequencing (mNGS). The detection rate of mNGS was higher than that of PCR assay (100 vs 66.7%, p < 0.05) and serum IgM antibody (100 vs 68.8%, p < 0.05) measurement. Of the 18 cases, five patients were diagnosed with acute meningitis, three with acute meningitis combined with facial neuritis, three with acute meningitis combined with polycranial neuritis, and the remaining seven with various clinical diagnoses. Typical clinical symptoms included headache (15), fever (9), and rash (11). Cranial or spinal MRI showed abnormalities in 12 patients, and 17 patients had obvious neurological symptoms. The predominant genotype of VZV in this study was genotype J (100%, 10/10). All patients were treated with acyclovir/penciclovir and dexamethasone, 16 recovered and 2 died. Our study highlights the good performance of mNGS in diagnosing CNS infection caused by VZV. It could provide additional diagnostic evidence in patients with diverse clinical spectrum and variable manifestations.

Transverse myelitis caused by herpes zoster following COVID-19 vaccination: A case report

BACKGROUND

Transverse myelitis (TM) is characterized by sudden lower extremity progressive weakness and sensory impairment, and most patients have a history of advanced viral infection symptoms. A variety of disorders can cause TM in association with viral or nonviral infection, vascular, neoplasia, collagen vascular, and iatrogenic, such as vaccination. Vaccination has become common through the global implementation against coronavirus disease 2019 (COVID-19) and reported complications like herpes zoster (HZ) activation has increased.

CASE SUMMARY

This is a 68-year-old woman who developed multiple pustules and scabs at the T6-T9 dermatome site 1 wk after vaccination with the COVID-19 vaccine (Oxford/ AstraZeneca ([ChAdOx1S{recombinant}]). The patient had a paraplegia aggravation 3 wk after HZ symptoms started. Spinal magnetic resonance imaging (MRI) showed transverse myelitis at the T6–T9 Level. Treatment was acyclovir with steroids combined with physical therapy. Her neurological function was slowly restored by Day 17.

CONCLUSION

HZ developed after COVID-19 vaccination, which may lead to more severe complications. Therefore, HZ treatment itself should not be delayed. If neurological complications worsen after appropriate management, an immediate diagnostic procedure, such as magnetic resonance imaging and laboratory tests, will start and should treat the neurological complications.

Transverse myelitis in children and adults

Transverse myelitis is a noncompressive myelopathy of inflammatory origin. The causes are broad, ranging from infective or toxic to immuno-mediated etiology. They can be manifestations of systemic diseases, such as sarcoidosis and systemic lupus erythematous, or phenotypes of neuroinflammation; in a portion of cases, the etiology remains unknown, leading to the designation idiopathic. The clinical presentation of transverse myelitis depends on the level of spinal cord damage and may include sensorimotor deficits and autonomic dysfunction. The age of onset of the disorder can impact the symptoms and outcomes of affected patients, with differences in manifestation and prognosis between children and adults. Spinal cord magnetic resonance imaging and cerebrospinal fluid examination are the main diagnostic tools that can guide clinicians in the diagnostic process, even though the search for antibodies that target the structural components of the neural tissue (anti-aquaporin4 antibodies and anti-myelin-oligodendrocyte antibodies) helps in the distinction among the immune-mediated phenotypes. Management and outcomes depend on the underlying cause, with different probabilities of relapse according to the phenotypes. Hence, immunosuppression is often recommended for the immune-mediated diseases that may have a higher risk of recurrence. Age at onset has implications for the choice of treatment.

[Reactivation of latent viruses in Neurology]

After establishing latent infection, some viruses can be reactivated by the alteration of host immunological conditions. First, we reviewed viruses that can cause neuronal damage by reactivation. Then we focused on the herpes simplex virus (HSV). The reactivation leads to neuronal damages through two possible mechanisms; "reactivation of a latent herpes virus" by which viruses can cause direct virus neurotoxicity, and "post-infectious immune inflammatory response" by which a focal reactivation of HSV leads to an inflammatory reaction. The former is radiologically characterized by cortical lesions, the latter is characterized by subcortical white matter lesions. We experienced a female, who underwent the right posterior quadrantectomy and then developed recurrent herpes encephalitis caused by herpes simplex reactivation, which pathologically demonstrated inflammation in the white matter, suggesting a post-infectious immune inflammatory response. The patient was successfully treated with immunosuppressants. The reactivation of the HSV is extremely rare in Japan. Neurologists should recognize this condition because this disorder will increase as epilepsy surgery gains more popularity.

A Case of Varicella-Zoster Virus Meningomyelitis in an HIV-1-Infected Patient: Facing the Challenges Related to Its Management and Prognosis

Varicella-zoster virus (VZV) myelitis is a rare complication of herpes zoster. Diagnosing and treating this entity may be challenging. Clinical outcomes vary and neurological sequelae may be seen despite treatment. We report a case of a 43-year-old woman with human immunodeficiency virus type 1 (HIV-1) infection (CD4 cell count 191 cells/µL - 14%; undetectable viral load) who was started on antiretroviral treatment eight months before. She presented with VZV meningitis and transverse myelitis and concomitant thoracic vesicular rash at the dermatomal level T6. Neurological examination revealed neck stiffness, paraplegia, sensory level below T4, and autonomic dysfunction. Magnetic resonance imaging (MRI) revealed signs of myelitis from C4 to T10 and VZV DNA by polymerase chain reaction (PCR) was positive (20,00,000 cp/mL) in the cerebrospinal fluid (CSF). The patient completed four weeks of intravenous acyclovir and systemic corticosteroids. Repeat lumbar puncture returned negative for VZV PCR and MRI showed spinal cord improvement. However, only partial neurological improvement was observed after six months. Some features of the present case may be associated with an unfavorable outcome, including high VZV viral load in the CSF and rapid progression of neurological deficits to paraplegia and sphincter dysfunction. Moreover, the recovery of CD4+ cells from 4% to 14% after starting antiretroviral treatment might also have contributed to the extension of myelopathy. Further studies are needed to improve the understanding of VZV myelitis course and optimize its treatment.

A Possible Case of Varicella Zoster Virus (VZV) Meningoencephalitis in an Immunocompetent Host

The herpes zoster infection occurs in the United States, particularly targeting those who are immunocompromised, and can present with many manifestations including encephalitis. Instances of varicella zoster virus (VZV) encephalitis in immunocompetent patients have been rarely reported, but such diagnoses are becoming more frequent as detection of VZV has improved with the adoption of molecular diagnostic panels such as the BioFire Film Array meningitis panel (Salt Lake City, USA). Here, we present an interesting case of acute meningoencephalitis in an immunocompetent adult female without dermatomal neuralgia or cutaneous lesions attributable to VZV. Given many inconsistencies between the patient’s presentation and the positive polymerase chain reaction (PCR) result for VZV, we suspected our patient was infected with an undetected organism while possibly simultaneously shedding previously acquired VZV. As molecular diagnostic panels are increasingly used and have greatly improved detection of rarer etiologies of disease, we encourage clinicians to interpret results with caution.

Acute myelitis with multicranial neuritis caused by Varicella zoster virus: a case report

Background

Varicella zoster virus (VZV) can remain lifelong in the latent state in ganglionic neurons and adrenal glands after the initial infection. However, it can be reactivated anytime and can trigger several severe neurological manifestations such as encephalitis, meningitis, Ramsay-Hunt syndrome, cerebellitis, myelitis, and stroke. In addition, due to the diversity of clinical manifestations, clinical diagnosis of VZV can be difficult, especially in the absence of varicella. Here, we describe the case of a 52-year-old male who presented with symptoms of acute myelitis as well as polycranial neuritis, and was finally diagnosed with VZV infection through metagenomic next-generation sequencing (mNGS).

Case presentation

A 52-year-old male came to our hospital with complaint of headache, fever, weakness of right lower limb, abdominal distension, and hearing loss. T2-weighted MRI revealed a hyperintense lesion in the spinal cord extending from T8 to T11. In addition, enhanced MRI showed small patches and strips hyperintensities in both the spinal cord and meninges. Plain abdominal radiographs and abdominal computed tomography (CT) scan displayed air-fluid levels and incomplete bowel obstruction. Moreover, electrophysiological evaluation of the peripheral neuropathy in the extremities was found to be normal. Finally, by using metagenomic next-generation sequencing (mNGS) we found that the copy number of VZV DNA in cerebrospinal fluid (CSF) was significantly increased and IgG antibody against VZV in CSF was also noted to be positive. Hence, VZV infection was identified in patient’s central neuron system. Finally, after a few days of low dose steroid treatment, the patient's symptoms were found to be significantly improved.

Conclusions

The findings indicate that we should pay proper attention to the various symptoms caused by VZV infection due to the clinical heterogeneity, especially in the absence of cutaneous lesions.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease and Varicella Zoster Virus Infection - Frequency of an Association

To determine whether there is a correlation between myelin oligodendrocyte glycoprotein (MOG) antibody-associated diseases and varicella zoster virus (VZV) infection. We provide a case report and performed a study to determine the frequency of MOG antibodies (MOG-IgG) in neurological VZV infections. Patients admitted to the Medical University of Innsbruck from 2008-2020 with a diagnosis of a neurological manifestation of VZV infection (n=59) were included in this study; patients with neuroborreliosis (n=34) served as control group. MOG-IgG was detected using live cell-based assays. In addition, we performed a literature review focusing on MOG and aquaporin-4 (AQP4) antibodies and their association with VZV infection. Our case presented with VZV-associated longitudinally extensive transverse myelitis and had MOG-IgG at a titer of 1:1280. In the study, we did not detect MOG-IgG in any other patient neither in the VZV group (including 15 with VZV encephalitis/myelitis) nor in the neuroborreliosis group. In the review of the literature, 3 cases with MOG-IgG and additional 9 cases with AQP4 IgG associated disorders in association with a VZV infection were identified. MOG-IgG are rarely detected in patients with VZV infections associated with neurological diseases.

Transverse myelitis caused by varicella-zoster

Transverse myelitis is a rare neurological complication seen with varicella-zoster virus (VZV) infection, which is common among immunocompromised hosts. It can occur during the primary VZV infection or reactivation of latent infection. It is a complication that requires prompt diagnosis and treatment. The present case is that of a 28-year-old immunocompetent man, who presented with fever, rash and acute-onset spastic paraparesis with bladder involvement. Causes such as herpes simplex 1 and 2, cytomegalovirus, enterovirus and Epstein-Barr virus infection were ruled out. On evaluation, he was diagnosed with acute primary disseminated VZV infection with parainfectious transverse myelitis, based on positive cerebrospinal fluid multiplex PCR (PCR) and serum VZV IgM antibodies. He was treated with intravenous acyclovir and steroids, with which he improved significantly.

Central nervous system infections produced by varicella zoster virus

PURPOSE OF REVIEW

Varicella zoster virus (VZV) causes varicella, establishes latency, then reactivates to produce herpes zoster. VZV reactivation can also cause central nervous system (CNS) disease with or without rash. Herein, we review these CNS diseases, pathogenesis, diagnosis, and treatment.

RECENT FINDINGS

The most common CNS manifestation of VZV infection is vasculopathy that presents as headache, cognitive decline, and/or focal neurological deficits. VZV vasculopathy has also been associated with cerebral amyloid angiopathy and moyamoya syndrome. Rarely, VZV will produce a meningitis, encephalitis, cerebellitis, and myelopathy. Pathogenic mechanisms include direct VZV infection of affected tissue, persistent inflammation, and/or virus-induced hypercoagulability. Diagnosis is confirmed by the temporal association of rash to disease onset, intrathecal synthesis of anti-VZV antibodies, and/or the presence of VZV DNA in CSF. Most cases respond to intravenous acyclovir with corticosteroids.

SUMMARY

VZV produces a wide spectrum of CNS disorders that may be missed as some cases do not have an associated rash or a CSF pleocytosis. Clinicians must be vigilant in including VZV in their differential diagnosis of CNS infections as VZV is a ubiquitous pathogen; importantly, VZV CNS infections are treatable with intravenous acyclovir therapy and corticosteroids.

Herpes Zoster Radiculomyelitis With Aquaporin-4 Antibodies: A Case Report and Literature Review

Background: The relationship between varicella-zoster virus (VZV)-associated myelitis and aquaporin-4 immunoglobulin-G (AQP4-IgG) remains unknown.

Case Report: We report a case of acute radiculomyelitis with longitudinal extensive hyperintensity signals traversing the brainstem until the upper thoracic cord in a 55-year-old healthy woman following herpes zoster infection in the left C4-T3 dermatome. VZV-specific IgG in the cerebrospinal fluid (CSF) and AQP4-IgG positivity on enzyme-linked immunosorbent assay (ELISA) were undetectable. Thus, she was diagnosed with immune-competent VZV radiculomyelitis. Forty-two months later, she experienced a relapse, and AQP4-IgG positivity was detected on ELISA. A cell-based assay (CBA) showed AQP4-IgG positivity not only at the time of recurrence but also retrospectively at 1 month after the initial symptoms. We concluded that AQP4-IgG-positive neuromyelitis optica spectrum disorder (NMOSD) was concurrent with VZV myelitis. After the second attack, she was treated with azathioprine and has had no relapse since then.

Conclusion: We reported a case of VZV radiculomyelitis with confirmed concurrent AQP4-IgG positivity. NMOSD induced by herpes zoster has been recently identified, but distinguishing it from VZV myelitis can be difficult and whether these two diseases aggravate each other is unknown. Awareness of the potentially varied presentation of VZV myelitis can enable earlier recognition and proper treatment.

Long-segment transverse myelitis in an immunocompetent patient due to varicella zoster virus reactivation

Transverse myelitis is a segmental, full-thickness inflammation of the spinal cord with various etiologies including varicella zoster virus infection. Symptoms can manifest as sensory deficits, severe lower back pain radiating down the legs, bowel/bladder incontinence, and extremity weakness. This case report is unique in that it highlights a patient who developed long-segment transverse myelitis after a varicella zoster virus infection which has not been previously reported in the literature.

Chronic myelitis associated with zoster sine herpete: A case report

RATIONALE

Neurological complications of varicella-zoster virus (VZV) infection include cerebral infarction, meningoencephalitis, segmental sensory disturbance, facial nerve palsy, and myelitis. Chronic myelitis is rarely reported. Diagnosis of VZV infection can be confirmed by elevated anti-VZV immunoglobulin G (IgG) antibody or detection of VZV DNA in the cerebrospinal fluid (CSF), the former reported to be superior. The detection rate of VZV DNA is generally thought to decrease with time after the onset of the condition. The utility of VZV DNA polymerase chain reaction (PCR) is thus thought to be limited to the acute phase of the disease. The presence of skin lesions also helps to render a diagnosis; however, cases of zoster sine herpete (ZSH), the occurrence of segmental symptoms without skin lesions, renders the diagnosis of VZV infection more difficult. Antiviral drugs, such as acyclovir, are the treatment of choice to resolve VZV infections.

PATIENT CONCERNS

A 65-year-old Japanese man felt heaviness and a throbbing pain on the ulnar side of the right forearm. He was previously diagnosed with cervical spondylosis, and received nonsteroidal anti-inflammatory drugs with little improvement. Contrast cervical magnetic resonance imaging showed a swelling and an increased signal intensity of the spinal cord, and an enhancing lesion, all of which were suggestive of myelitis.

DIAGNOSIS

We found no evidence for diagnoses of sarcoidosis, Behçet disease, multiple sclerosis, or neuromyelitis optica spectrum disorder. The CSF analysis revealed an elevation of the total protein concentration and that the patient was positive for VZV DNA, while anti-VZV IgG was not elevated. The patient was therefore diagnosed with ZSH myelitis.

INTERVENTIONS

We administered acyclovir and valaciclovir as the first therapy. At the time of recurrence, we used high-dose acyclovir, vidarabine, and high-dose methylprednisolone pulse therapy.

OUTCOMES

The patient's dysesthetic pain in the right upper limb improved following the first antiviral therapy. Two months later, he suffered a recurrence, but the second therapy significantly relieved his symptoms.

LESSONS

VZV infection should be regarded as an important differential diagnosis of chronic myelitis. VZV DNA PCR should be performed even in the chronic phase of the condition to introduce the possibility of antiviral therapy as a treatment option.

Longitudinal Extensive Transverse Myelitis in an Immunocompetent Older Individual-A Rare Complication of Varicella-Zoster Virus Reactivation

Varicella-zoster virus (VZV) is a human neurotropic herpes virus that causes chickenpox in children. After becoming latent in dorsal root ganglia, it can reactivate to cause dermatological manifestations, the most common one being shingles or herpes zoster. Severe neurologic dysfunctions can occur in immunocompromised patients such as encephalitis, meningitis, myelitis and neuropathy. Longitudinal extensive transverse myelitis (LETM) is an unusual neurological complication mainly described in immunocompromised patients, with very few cases described in immunocompetent ones. We hereby report a case of VZV-induced LETM in an immunocompetent older adult—a situation rarely described in the literature. LETM is a rare complication of VZV and its pathogenesis; therapeutic interventions and prognosis are far from being fully clarified. However, a prompt diagnosis is needed to allow a rapid initialization of treatment and ensure a better outcome. Although the therapeutic lines are not clear, immunosuppressive agents may have their place in cases of unsuccessful results and/or relapses following acyclovir coupled with a well conducted methylprednisolone therapy. Further studies are highly needed to improve the current understanding of the disease course and mechanisms, and to optimize therapeutic strategies.

Long-term outcomes of varicella zoster virus infection-related myelitis in 10 immunocompetent patients

OBJECTIVE

To describe the clinical presentation and long-term disease outcomes of varicella zoster virus (VZV) infection-related myelitis (VZVM) in immunocompetent patients.

METHOD

A series of 10 immunocompetent patients with VZVM were retrospectively observed and followed (3-96 months).

RESULTS

The onset of myelitis was timed in relation to the appearance of VZV-associated rash (-3 to 50 days). Rash locations included the cervical (5), thoracic (2), and lumbar (3) dermatomes, whereas myelitis localized to the cervical (6) and thoracic (9) spinal cord and the medulla (1). Spinal MRI revealed extensive longitudinal transverse myelitis in nine patients, with multiple segmental lesions (≥2 segments) evident in five patients. Aquaporin-4, myelin oligodendrocyte glycoprotein, ganglioside Q1b, and ganglioside T1b antibodies were detected in some patients. Three patients fulfilled the 2015 diagnostic criteria for neuromyelitis optica spectrum disease, of whom two relapsed. Seven patients were treated with intravenous antivirals and methylprednisolone, with the remaining three patients receiving methylprednisolone only. Ongoing immunosuppressive therapy was provided for two patients who experienced relapses. To date, no patients have reported VZV reactivation. Over the course of follow-up, the Expanded Disability Status Scale (EDSS) score deceased from 4.9 to 2.6 on average.

CONCLUSIONS

VZVM runs a relatively benign course in immunocompetent patients, although relapses can occur depending on patient immune status. A comprehensive evaluation of patient's autoimmune condition is recommended.

A Case of Transverse Myelitis Caused by Varicella Zoster Virus in an Immunocompetent Older Patient

Varicella zoster virus (VZV) is a human neurotropic alphaherpesvirus that causes chickenpox (varicella) in children. VZV reactivation may lead to neurological complications, including transverse myelitis. However, transverse myelitis caused by VZV reactivation is rare in immunocompetent patients. Herein, we report a case of transverse myelitis caused by VZV in an immunocompetent older patient, and confirmed this case by polymerase chain reaction. A 79-year-old woman visited our service with complaints of weakness in the right lower leg, generalized vesicular eruptions, and throbbing pain in the right flank for ten days. Spine MRI showed transverse myelitis in the thoracic spine at level T4-T11. The patient was treated with acyclovir and her neurological functions improved, except for sensory impairment below level T10. For older patients, early and aggressive antiviral treatment against VZV may be necessary even though these patients are immunocompetent.

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.

Varicella-zoster virus encephalomyelitis with a prominent demyelinating component

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

Extensive VZV Encephalomyelitis without Rash in an Elderly Man

Introduction. Varicella zoster virus (VZV) encephalomyelitis with cranial nerve involvement is rare. Characteristically it is preceded by a rash and primarily presents in the immunocompromised. The spectrum of VZV neurologic disease is extensive and it is not uncommon to present without rash. We report the case of an elderly otherwise immunocompetent patient who presented with diverse manifestations of VZV CNS infection all occurring without rash. Case Report. A 78-year-old man presented with 1 week of progressive paraparesis and sensory loss, malaise, and fevers. MRI of the neuraxis demonstrated numerous enhancing lesions: intramedullary, leptomeningeal, pachymeningeal, and cranial nerves. Cerebrospinal fluid (CSF) showed a white blood cell count of 420/μL with elevated protein (385 mg/dL). CSF VZV qualitative PCR was positive and CSF VZV immunofluorescence assay detected IgM antibody, confirming the diagnosis of VZV encephalomyelitis. Clinical and radiological improvement was observed after intravenous acyclovir treatment. Conclusion. This is a rare report of an immunocompetent patient with extensive VZV encephalomyelitis. We highlight the importance of considering this diagnosis even in the absence of the characteristic rash, and the potential risk of premature discontinuation of antiviral therapy once HSV has been excluded. Prompt recognition and treatment can dramatically reduce morbidity and mortality in patients.

Basics of virology

Viruses are important pathogens of the nervous system. Here we describe the basic properties of viruses and the principles of virus classification, evolution, structure, and replication, with a focus on neurotropic viruses that are important neuropathogens of humans. These properties then provide the background for introductions to pathogenesis of viral diseases of the nervous system, host immune responses to virus infection, and the diagnosis and treatment of virus infections of the nervous system.

Herpes myelitis after thoracic spine surgery

Herpes simplex or herpes zoster reactivation after spinal surgery is rarely reported. This case report and review of the literature describes patients in whom this reactivation occurs to clarify the diagnosis and management. In addition to reporting their case, the authors reviewed case reports and series published between 1980 and 2012 found through a PubMed search. Herpes reactivation is generally confined to a vesicular rash that can be treated with acyclovir. However, occasional dissemination has occurred and has led to myelitis or encephalitis. Atypical presentations led to delays in diagnosis, delayed treatment, and poor neurological outcome. While rare, herpes simplex or herpes zoster reactivation is a complication of spine surgery that must be considered in the face of new-onset focal neurological symptoms in a dermatome pattern without a structural cause, even without a rash.