Rapid diagnosis of varicella zoster virus infection in acute facial palsy

Quantitation of varicella-zoster virus DNA in patients with Ramsay Hunt syndrome and zoster sine herpete

Varicella-zoster virus (VZV) reactivation causes facial nerve palsy in Ramsay Hunt syndrome (RHS) and zoster sine herpete (ZSH) with and without zoster rash, respectively. In the present study, we analyzed the VZV DNA copy number in saliva samples from 25 patients with RHS and 31 patients with ZSH using a TaqMan PCR assay to determine differences in the viral load between the two diseases. VZV copy number in saliva peaked near the day of the appearance of zoster in patients with RHS. Consequently, VZV DNA was less frequently detected in patients with RHS who exhibited facial palsy several days after the appearance of zoster. These findings suggest that the VZV load in saliva samples reflects the kinetics of viral reactivation in patients with RHS. In addition, VZV DNA was equally detected in saliva from patients with RHS and ZSH, and there was no significant difference in the highest viral copy number between patients with RHS and those with ZSH. The VZV load does not appear to reflect a major difference between RHS and ZSH.

Ramsay Hunt syndrome

The strict definition of the Ramsay Hunt syndrome is peripheral facial nerve palsy accompanied by an erythematous vesicular rash on the ear (zoster oticus) or in the mouth. J Ramsay Hunt, who described various clinical presentations of facial paralysis and rash, also recognised other frequent symptoms and signs such as tinnitus, hearing loss, nausea, vomiting, vertigo, and nystagmus. He explained these eighth nerve features by the close proximity of the geniculate ganglion to the vestibulocochlear nerve within the bony facial canal. Hunt's analysis of clinical variations of the syndrome now bearing his name led to his recognition of the general somatic sensory function of the facial nerve and his defining of the geniculate zone of the ear. It is now known that varicella zoster virus (VZV) causes Ramsay Hunt syndrome. Compared with Bell's palsy (facial paralysis without rash), patients with Ramsay Hunt syndrome often have more severe paralysis at onset and are less likely to recover completely. Studies suggest that treatment with prednisone and acyclovir may improve outcome, although a prospective randomised treatment trial remains to be undertaken. In the only prospective study of patients with Ramsay Hunt syndrome, 14% developed vesicles after the onset of facial weakness. Thus, Ramsay Hunt syndrome may initially be indistinguishable from Bell's palsy. Further, Bell's palsy is significantly associated with herpes simplex virus (HSV) infection. In the light of the known safety and effectiveness of antiviral drugs against VZV or HSV, consideration should be given to early treatment of all patients with Ramsay Hunt syndrome or Bell's palsy with a 7-10 day course of famciclovir (500 mg, three times daily) or acyclovir (800 mg, five times daily), as well as oral prednisone (60 mg daily for 3-5 days). Finally, some patients develop peripheral facial paralysis without ear or mouth rash, associated with either a fourfold rise in antibody to VZV or the presence of VZV DNA in auricular skin, blood mononuclear cells, middle ear fluid, or saliva. This indicates that a proportion of patients with "Bell's palsy" have Ramsay Hunt syndrome zoster sine herpete. Treatment of these patients with acyclovir and prednisone within 7 days of onset has been shown to improve the outcome of recovery from facial palsy.

Bell's Palsy and Herpes Zoster Oticus

Normal facial movement is required for chewing, swallowing, speaking, and protecting the eye. Bell's palsy causes most cases of acute, unilateral facial palsy; infection with herpes simplex virus (HSV) type 1 may be its major cause. Varicella zoster virus (VZV) reactivation (Ramsay Hunt syndrome) is less common, but may appear without skin lesions in a form indistinguishable from Bell's palsy. Symptoms improve in nearly all patients with Bell's palsy, and most patients with Ramsay Hunt syndrome, but many are left with functional and cosmetic deficits. Steroids are frequently used to optimize outcomes in Bell's palsy, but proof of their effectiveness is marginal. Oral prednisone has been studied extensively, although some reports have suggested a higher recovery rate with intravenous steroids. Given the existing data, we support the use of oral prednisone in those patients with complete facial palsy, and no contraindications to their use (Fig. 1). In this author's opinion, the greatly increased cost and inconvenience of intravenous steroids cannot be justified by the data available. Antiviral agents may also be effective in treatment of Bell's palsy; HSV is susceptible to acyclovir and related agents. There have been few investigations of acyclovir treatment in Bell's palsy, but one controlled study showed added benefit when the drug was used with prednisone. The risk and cost of acyclovir is low enough that we support its use, with oral steroids, in those patients with complete facial paralysis. Several small studies have implied that oral acyclovir improves the outcome of facial palsy for patients with Ramsay Hunt syndrome. Although these studies do not prove efficacy, evidence for the benefits of antiviral agents in other forms of zoster is strong enough to recommend their use when the facial nerve is involved. VZV is less sensitive to acyclovir than HSV, so higher doses are recommended to treat Ramsay Hunt syndrome. Because some Ramsay Hunt syndrome patients with partial facial palsy do not fully recover, we recommend oral antiviral agents in all patients suspected of having zoster. There is weak evidence to suggest additional benefit of oral steroids in facial zoster, and their use can be supported in immunocompetent individuals. Facial nerve decompression surgery for Bell's palsy and herpes zoster oticus has experienced varying levels of enthusiasm over the years. Recent work implies that early, extensive decompression of the nerve through a middle fossa craniotomy may benefit patients at high risk for persistent deficits. However, until this procedure is subjected to a rigorous, controlled trial comparing it with maximal medical therapy, it is difficult to justify the very high costs and risk.

Bell's palsy and herpes viruses: to (acyclo)vir or not to (acyclo)vir?

The majority of peripheral seventh cranial nerve palsy cases remain without an identified etiology and will eventually be diagnosed as idiopathic or Bell's palsy. Some features of this condition may be characteristic of a viral infection. Indeed, several herpes viruses have been implicated as potential causative pathogens. Besides varicella-zoster virus, shown to cause Bell's palsy under the Ramsay-Hunt syndrome, recent years have seen an increased interest and focus on the possible herpes simplex virus type 1 (HSV-1) etiology in idiopathic facial paralysis. We review the clinical, biological and virological basis for the potential herpetic cause of Bell's palsy and the rational for antiviral therapy in this condition.

Delayed facial palsy after middle-ear surgery due to reactivation of varicella-zoster virus

Viral reactivation is thought to be an important cause of post-operative facial palsy of delayed onset. We present an unusual case of Ramsay-Hunt syndrome that occurred as a consequence of middle-ear surgery by triggering varicella-zoster virus reactivation. As a pathognomonic auricular eruption was not seen, the patient was initially misdiagnosed as iatrogenic facial palsy. Clinical features, diagnosis and management are discussed.