**2. Zoster sine herpete**

If neurological symptoms occur simultaneously or around the same time as the onset of herpes zoster infection, they can be considered complications of VZV infections. However, if lesions such as rashes, shingles, or blisters are not observed, VZV as a causative agent is likely to be missed. In fact, because VZV can cause CNS complications in the absence of skin lesions, such cases are referred to as zoster sine herpete [9]; clinicians have to consider the possibility of VZV as a causative virus in patients with neurological infections, such as meningitis or encephalitis (**Figure 1**).

### **3. Aseptic meningitis**

Meningitis is inflammation of the pia mater and the arachnoid that cover the surface of the brain. Its clinical signs include fever, headache, nausea, vomiting, and meningeal irritation symptoms, such as nuchal rigidity and Kernig's sign. Furthermore, jolt accentuation and neck flexion tests are often positive. However, these are common symptoms and findings of meningitis regardless of the cause. The CSF examination shows monocyte-dominant pleocytosis and elevated protein levels with normal glucose levels. Patients with meningitis wherein bacteria are not detected via the CSF test are generally diagnosed as having aseptic meningitis. Most cases of aseptic meningitis involve viral meningitis. The most common virus that causes viral meningitis is enterovirus. In adults, enterovirus is followed by herpes simplex virus type 2 (HSV-2) and VZV [10], and VZV infection accounts for 8% of the total meningitis cases [11].

VZV meningitis can sometimes cause cranial polyneuropathy or dysuria due to sacral radiculopathy, and dysuria due to sacral radiculopathy is known as Elsberg syndrome. Meningitis caused by VZV is also frequently observed among healthy young individuals. Such a condition generally has a good prognosis and rarely causes any sequelae.

### **4. Elsberg syndrome**

Elsberg syndrome is caused by bilateral sacral radiculopathy, which is characterized by urinary retention, sensory disturbance, and neuralgia of the perineum

**35**

*Neurologic Complications of Varicella-Zoster Virus Infection*

However, this condition resolves as meningitis improves.

and lower limbs. Although Elsberg syndrome was originally characterized by urinary retention due to sacral radiculopathy associated with genital herpes, it is now defined as aseptic meningitis-associated sacral radiculopathy. As the causative virus, HSV, particularly HSV-2, is the most common cause, followed by VZV [12, 13]. When urinary retention occurs, urethral catheterization is required.

A 32-year-old man was admitted to our hospital because of high fever, headache, nausea, acute urinary retention, and dysesthesia in a lumbosacral dermatome distribution. There were no motor symptoms and no rash. CSF analysis showed 249

enhanced MRI revealed the meningeal lesions of the conus medullaris and the swollen radicular fibers in the upper lumbar spinal canal. Treatment of acyclovir and dexamethasone for 2 weeks led to complete resolution of meningitis and urinary retention.

**5. Encephalitis and cerebral infarction associated with granulomatous** 

The symptoms of encephalitis include acute disturbance of consciousness, headache, fever, and convulsions. Neurological findings of encephalitis include meningeal irritation symptoms, such as nuchal rigidity; however, patients with encephalitis sometimes present with motor paralysis and sensory disturbance due to

Among the pathogens that cause viral encephalitis, VZV is the second most common cause following HSV, accounting for 5% of the total encephalitis cases [14]. According to a recent analysis that used PCR, though, the risk of VZV encephalitis increases in elderly individuals, those with herpes zoster ophthalmicus, and those with disseminated herpes zoster, and this result indicates that the incidence of VZV

The clinical manifestations of VZV encephalitis include meningoencephalitis and vasculopathy [16]. The meningoencephalitis form shows no detectable lesions on MRI. In contrast, the vasculopathy form is characterized by non-specific ischemia, hemorrhagic lesions, and multiple white matter lesions on MRI [16]. Pathological studies suggested that VZV encephalitis develops based on vasculopathy in the large and small vessels. Therefore, MRI typically demonstrates ischemic or hemorrhagic infarction in both gray and white matter and particularly at graywhite matter junctions as characteristic imaging findings of VZV encephalitis [16]. In VZV encephalitis, lesions in the temporal lobe and limbic system, which are often observed in patients with herpes simplex encephalitis, are rare. Moreover, hemorrhagic lesions and necrosis, which are characteristics of herpes simplex encephalitis, are not commonly observed. Because VZV DNA is generally detected in the CSF of adult patients with VZV encephalitis, direct viral invasion to the CNS is believed to be the pathology of VZV encephalitis. In contrast, in varicella encephalitis in children who develop acute cerebellar ataxia associated with varicella infection, VZV is not detected in the CSF. Therefore, a secondary immunological allergic mechanism

Cerebral infarction caused by granulomatous vasculitis is a complication of herpes zoster infection [1, 17]. A typical patient presents with herpes zoster ophthalmicus, followed by postherpetic contralateral hemiplegia, and develops cerebral infarction between the eighth day and sixth month after herpes zoster infection

, 70 mg/dl protein, and positive of VZV DNA by PCR. Gadolinium-

*DOI: http://dx.doi.org/10.5772/intechopen.83036*

**4.1 Case 1: Elsberg syndrome**

leukocytes/mm3

**vasculitis**

parenchymal brain damage.

encephalitis might have increased [15].

is considered as the pathology of varicella encephalitis.

and lower limbs. Although Elsberg syndrome was originally characterized by urinary retention due to sacral radiculopathy associated with genital herpes, it is now defined as aseptic meningitis-associated sacral radiculopathy. As the causative virus, HSV, particularly HSV-2, is the most common cause, followed by VZV [12, 13]. When urinary retention occurs, urethral catheterization is required. However, this condition resolves as meningitis improves.

### **4.1 Case 1: Elsberg syndrome**

*Human Herpesvirus Infection - Biological Features, Transmission, Symptoms, Diagnosis...*

If neurological symptoms occur simultaneously or around the same time as the onset of herpes zoster infection, they can be considered complications of VZV infections. However, if lesions such as rashes, shingles, or blisters are not observed, VZV as a causative agent is likely to be missed. In fact, because VZV can cause CNS complications in the absence of skin lesions, such cases are referred to as zoster sine herpete [9]; clinicians have to consider the possibility of VZV as a causative virus in patients with neurological infections, such as meningitis or encephalitis (**Figure 1**).

Meningitis is inflammation of the pia mater and the arachnoid that cover the surface of the brain. Its clinical signs include fever, headache, nausea, vomiting, and meningeal irritation symptoms, such as nuchal rigidity and Kernig's sign. Furthermore, jolt accentuation and neck flexion tests are often positive. However, these are common symptoms and findings of meningitis regardless of the cause. The CSF examination shows monocyte-dominant pleocytosis and elevated protein levels with normal glucose levels. Patients with meningitis wherein bacteria are not detected via the CSF test are generally diagnosed as having aseptic meningitis. Most cases of aseptic meningitis involve viral meningitis. The most common virus that causes viral meningitis is enterovirus. In adults, enterovirus is followed by herpes simplex virus type 2 (HSV-2) and VZV [10], and VZV infection accounts for 8% of the total meningitis cases [11]. VZV meningitis can sometimes cause cranial polyneuropathy or dysuria due to sacral radiculopathy, and dysuria due to sacral radiculopathy is known as Elsberg syndrome. Meningitis caused by VZV is also frequently observed among healthy young individuals. Such a condition generally has a good prognosis and rarely

Elsberg syndrome is caused by bilateral sacral radiculopathy, which is characterized by urinary retention, sensory disturbance, and neuralgia of the perineum

**34**

**2. Zoster sine herpete**

*Neurological complications associated with VZV reactivation.*

**Figure 1.**

**3. Aseptic meningitis**

causes any sequelae.

**4. Elsberg syndrome**

A 32-year-old man was admitted to our hospital because of high fever, headache, nausea, acute urinary retention, and dysesthesia in a lumbosacral dermatome distribution. There were no motor symptoms and no rash. CSF analysis showed 249 leukocytes/mm3 , 70 mg/dl protein, and positive of VZV DNA by PCR. Gadoliniumenhanced MRI revealed the meningeal lesions of the conus medullaris and the swollen radicular fibers in the upper lumbar spinal canal. Treatment of acyclovir and dexamethasone for 2 weeks led to complete resolution of meningitis and urinary retention.
