Summary about Disease
Zoster myelitis is a rare neurological complication of varicella-zoster virus (VZV) reactivation, the same virus that causes chickenpox and shingles. It involves inflammation of the spinal cord (myelitis) following VZV reactivation. It typically occurs after a shingles rash, but in some cases, it may occur without a rash (zoster sine herpete). It can lead to significant neurological deficits.
Symptoms
Symptoms can vary, but commonly include:
Weakness in the legs or arms
Numbness, tingling, or burning sensations
Bowel and bladder dysfunction (difficulty urinating or controlling bowel movements)
Pain (may be localized or radiating)
Sensory loss
Headache
Fever
Causes
Zoster myelitis is caused by the varicella-zoster virus (VZV). After a person has chickenpox, VZV remains dormant in nerve cells. When the virus reactivates, it typically causes shingles (herpes zoster), a painful rash. In some cases, the reactivated virus can spread to the spinal cord, leading to inflammation and damage, resulting in zoster myelitis. The exact reasons why VZV reactivates and targets the spinal cord in some individuals are not fully understood, but it often involves a weakened immune system.
Medicine Used
Treatment primarily focuses on antiviral medications and supportive care. Common medications include:
Antiviral medications: Acyclovir, valacyclovir, or famciclovir are used to inhibit the replication of the varicella-zoster virus. High doses are usually required.
Corticosteroids: Prednisone or other corticosteroids may be used to reduce inflammation in the spinal cord.
Pain medications: Analgesics, including opioids, may be prescribed to manage pain.
Medications for bladder/bowel dysfunction: Medications to manage urinary retention or incontinence.
Muscle relaxants: To help alleviate muscle spasms.
Is Communicable
Zoster myelitis itself is not communicable. It's a complication arising from the reactivation of a virus already present in the body. However, someone with reactivated VZV (shingles) can transmit the virus to someone who has never had chickenpox or the chickenpox vaccine. In that case, the susceptible person would develop chickenpox, not zoster myelitis.
Precautions
Vaccination: The shingles vaccine (Zostavax or Shingrix) is highly recommended for adults over 50 to prevent VZV reactivation and reduce the risk of shingles and its complications.
Avoid contact: If someone has an active shingles rash, avoid direct contact with the rash, especially if you have never had chickenpox or the chickenpox vaccine.
Hygiene: Frequent handwashing can help prevent the spread of VZV.
Prompt treatment of shingles: Early treatment of shingles with antiviral medications can reduce the risk of complications like postherpetic neuralgia and possibly, though rarely, zoster myelitis.
How long does an outbreak last?
The acute phase of zoster myelitis, characterized by inflammation and symptom onset, typically lasts several weeks to a few months. However, the long-term effects and recovery period can vary significantly depending on the severity of the damage to the spinal cord and the individual's response to treatment. Some individuals may experience residual neurological deficits that persist for months or even years, while others may have a more complete recovery. The duration of symptoms and recovery can range from a few months to years.
How is it diagnosed?
Diagnosis typically involves:
Neurological examination: Assessing motor strength, sensation, reflexes, and bowel/bladder function.
MRI of the spinal cord: To visualize inflammation or lesions in the spinal cord.
Lumbar puncture (spinal tap): To analyze cerebrospinal fluid (CSF) for evidence of VZV infection, inflammation, and to rule out other causes. PCR testing of the CSF for VZV DNA is crucial.
Blood tests: To assess for VZV antibodies.
EMG/Nerve conduction studies: To assess nerve function if needed.
Timeline of Symptoms
The timeline of symptoms can vary, but a general progression may look like this:
Prodrome (days to weeks before rash/neurological symptoms): Some individuals may experience vague symptoms like fatigue, fever, or headache.
Shingles Rash (may be absent in zoster sine herpete): Painful, blistering rash that follows a dermatomal distribution (along a nerve pathway). This may or may not precede the myelitis.
Onset of Neurological Symptoms (days to weeks after rash): Weakness, numbness, tingling, pain, and bowel/bladder dysfunction develop. The onset can be gradual or rapid.
Plateau (weeks to months): Symptoms stabilize, but significant deficits may remain.
Recovery (months to years): Gradual improvement in motor strength, sensation, and bowel/bladder function may occur. The extent of recovery varies.
Important Considerations
Early diagnosis and treatment are crucial: Prompt initiation of antiviral therapy and corticosteroids may improve outcomes.
Long-term rehabilitation: Physical therapy, occupational therapy, and other rehabilitation services may be necessary to maximize functional recovery.
Pain management: Chronic pain is a common complication, and effective pain management strategies are essential.
Bowel and bladder management: Ongoing management of bowel and bladder dysfunction may be required.
Monitoring for complications: Regular neurological follow-up is important to monitor for complications and adjust treatment as needed.
Immunocompromised individuals: Individuals with weakened immune systems are at higher risk for zoster myelitis and may have more severe outcomes.