Ramsay Hunt syndrome type II

Ramsay Hunt syndrome (RHS) type 2 also known as herpes zoster oticus is a disorder that is caused by the reactivation of pre-existing Varicella zoster virus in the geniculate ganglion, a nerve cell bundle, of the facial nerve.

Ramsay Hunt syndrome type 2 typically presents with inability to move many facial muscles, pain in the ear, taste loss on the front of the tongue, dry eyes and mouth, and the eruption of an erythematous rash.

Signs and symptoms



The symptoms and signs include acute facial nerve paralysis, pain in the ear, taste loss in the front two-thirds of the tongue, dry mouth and eyes, and eruption of an erythematous vesicular rash in the ear canal, the tongue, and/or hard palate.

Since the vestibulocochlear nerve is in proximity to the geniculate ganglion, it may also be affected, and patients may also suffer from tinnitus, hearing loss, and vertigo.

Possible involvement of the trigeminal nerve can cause anaesthesia of the face.

Pathophysiology



RHS type 2 refers to shingles of the geniculate ganglion. After initial infection, varicella zoster virus lies dormant in various nerve cells in the body, where it is kept in check by the patient's immune system. Given the opportunity, for example during an illness that suppresses the immune system, the virus is reactivated and travels to the end of the nerve cell, where it causes the symptoms described above.

In RHS type 2, the affected ganglion is responsible for the movements of facial muscles, the touch sensation of a part of ear and ear canal, the taste function of the frontal two-thirds of the tongue, and the moisturization of the eyes and the mouth. The syndrome specifically refers to the combination of this entity with weakness of the muscles activated by the facial nerve. In isolation the latter entity would be called Bell's Palsy.

Like shingles, however, lack of lesions does not definitely exclude the existence of a herpes infection. The virus can be detected, even before the eruption of vesicles, from the skin of the ear.

Prevention



This disease is prevented by immunizing against the causal virus, varicella zoster, for example through Zostavax, a stronger version of chickenpox vaccine.

Treatment with the corticosteroid Prednisone and acyclovir has been shown to achieve complete recovery in a majority of patients if started within the first three days of facial paralysis, with chances of recovery decreasing as treatment was delayed. Delay of treatment may result in permanent facial nerve paralysis.

Treatment apparently has no effect on the recovery of hearing loss.

Diazepam is sometimes used to treat the vertigo.

History



It is named after James Ramsay Hunt.

References



External links



  • Ramsay Hunt syndrome at GPnotebook
  • NINDS Herpes Zoster Oticus Information Page National Institute of Neurological Disorders and Stroke
  • Ramsay-Hunt Syndrome. Support site.
  • drtbalu otolaryngology on line
  • Ramsay Hunt Syndrome Causes, Symptoms, Diagnoses
  • Vaccine at Centers for Disease Control and Prevention
  • MR scans Imaging Zoster Oticus


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