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      Anonymous
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      Varicella-zoster virus (VZV) causes chickenpox and herpes zoster (shingles). Chickenpox follows initial exposure to the virus and is typically a relatively mild, self-limited childhood illness with a characteristic exanthem, but can become disseminated in immunocompromised children. Reactivation of the dormant virus results in the characteristic painful dermatomal rash of herpes zoster, which is often followed by pain in the distribution of the rash (postherpetic neuralgia).

      Essential update: New CDC guidelines for varicella-zoster virus immune globulin use
      In July 2013, the CDC issued updated recommendations for the use of varicella-zoster immune globulin (VariZIG) to reduce the severity of VZV infection, extending the window for postexposure prophylaxis for those at high risk for severe varicella.[1, 2] The FDA’s original approval of VariZIG recommended use within 4 days, but subsequent studies have shown that the treatment is effective for up to 10 days after exposure.

      Other recommendations include the use of VariZIG in the following patients:

      Immunocompromised patients without evidence of immunity
      Newborn infants whose mothers have varicella symptoms between 5 days before and 2 days after delivery
      Hospitalized premature infants born at 28 weeks of gestation or later whose mothers do not have evidence of immunity to varicella
      Hospitalized premature infants born at less than 28 weeks of gestation or who weigh less than 1000 g at birth, regardless of their mothers’ evidence of immunity to varicella
      Pregnant women without evidence of immunity
      Signs and symptoms
      Pain and paresthesia are typically the first symptoms of VZV infection. Until the characteristic vesicular rash erupts, diagnosis may be difficult. A prodromal period during which symptoms may vary is common. Pain occurs in 41% of patients, itching in 27%, and paresthesias in 12%.

      During the acute illness, patients may experience the following:

      Pain (90%)
      Helplessness and depression (20%)
      Flulike symptoms (12%)
      Herpes zoster (shingles)

      The most common presentation is the shingles vesicular rash, which most commonly affects a thoracic dermatome
      After a prodromal illness of pain and paresthesias, erythematous macules and papules develop and progress to vesicles within 24 hours
      The vesicles eventually crust and resolve
      Pain and sensory loss are the usual symptoms
      Motor weakness also occurs and is frequently missed on examination
      Cases of actual monoplegia due to VZV brachial plexus neuritis have been reported
      Zoster multiplex

      Shingles may appear in multiple dermatomes, both contiguous and noncontiguous, on either side of the body
      Immunocompromised individuals are more susceptible
      Terminology depends on the number of involved dermatomes and on whether the condition is unilateral or bilateral (eg, zoster duplex unilateralis refers to the involvement of 2 unilateral dermatomes)
      Cases of zoster simultaneously occurring in 7 noncontiguous dermatomes have been reported
      Zoster sine herpete

      VZV infection may reactivate without causing cutaneous vesicles. These patients have severe dermatomal pain, possible motor weakness and possible hypesthesia, but no visible rash or vesicles.

      VZV infection may present as acute peripheral facial palsy in 8-25% of patients who have no cutaneous vesicles. This is more common in immunosuppressed patients who use acyclovir (or other agents) as zoster prophylaxis.[3]

      Central nervous system deficits

      More common in immunocompromised individuals, but do occur in the general population
      CNS involvement may become apparent 3 weeks after the onset of the initial rash
      The manifestations are usually bilateral
      The physical findings may progress
      The underlying pathology typically progresses for 3 or more weeks
      Progression for 6 months in immunocompromised individuals has been reported
      Recurrence is rare but has been reported
      Zoster encephalitis is also rare but is reported in otherwise healthy individuals
      Ramsay-Hunt syndrome

      This syndrome occurs when the geniculate ganglion is involved. The clinical presentation includes the following:

      A peripheral facial palsy
      Pain in the ear and face
      Vesicles in the external ear canal (not always present)
      Additional auditory and vestibular symptoms in some cases
      Keratitis (herpes ophthalmicus)

      Caused by reactivation of VZV infection in the ophthalmic division of the trigeminal nerve.
      The presentation may include conjunctivitis or corneal ulcers
      Complications include blindness
      Vesicles do not have to be present
      Rarely, the virus migrates along the intracranial branches of the trigeminal nerve, causing thrombotic cerebrovasculopathy with severe headache and hemiplegia
      See Clinical Presentation for more detail.

      Diagnosis
      When the presentation includes the typical dermatomal rash, additional studies are not required. Studies to consider in specific situations include the following:

      If the diagnosis is in doubt, a Tzanck smear or culture of vesicular fluid can be performed
      In cases of zoster sine herpete, DNA analysis via PCR can be used
      In cases of acyclovir-resistant VZV, detections of mutations in thymidine kinase can be determined by PCR and sequence analysis
      MRI may be useful if myelitis or encephalitis is suspected
      Lumbar puncture may be helpful if signs suggest myelitis or encephalitis

      Management
      Treatment options are based on the following:

      Patient age
      Patient immune state
      Duration of symptoms
      Presentation
      Antiviral medications decrease the duration of symptoms and the likelihood of postherpetic neuralgia, especially when initiated within 2 days of the onset of rash. Oral acyclovir may be prescribed in otherwise healthy patients who have typical cases. Compared with oral acyclovir, other medications (eg, valacyclovir, penciclovir, famciclovir) may decrease the duration of the patient’s pain.

      Varicella zoster immune globulin (VariZIG) is indicated for administration to high-risk individuals within 10 days (ideally within 4 days) of chickenpox (VZV) exposure.[4] High- risk groups include the following:

      Immunocompromised children and adults
      Newborns of mothers with varicella shortly before or after delivery
      Premature infants
      Infants less than younger than 1 year of age
      Adults without evidence of immunity
      Pregnant women
      See Treatment and Medication for more detail.

      I

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