Immune reactivity in Bell's palsy

Bell's palsy: a summary of current evidence and referral algorithm

Spontaneous idiopathic facial nerve (Bell's) palsy leaves residual hemifacial weakness in 29% which is severe and disfiguring in over half of these cases. Acute medical management remains the best way to improve outcomes. Reconstructive surgery can improve long term disfigurement. However, acute and surgical options are time-dependent. As family practitioners see, on average, one case every 2 years, a summary of this condition based on common clinical questions may improve acute management and guide referral for those who need specialist input. We formulated a series of clinical questions likely to be of use to family practitioners on encountering this condition and sought evidence from the literature to answer them. The lifetime risk is 1 in 60, and is more common in pregnancy and diabetes mellitus. Patients often present with facial pain or paraesthesia, altered taste and intolerance to loud noise in addition to facial droop. It is probably caused by ischaemic compression of the facial nerve within the meatal segment of the facial canal probably as a result of viral inflammation. When given early, high dose corticosteroids can improve outcomes. Neither antiviral therapy nor other adjuvant therapies are supported by evidence. As the facial muscles remain viable re-innervation targets for up to 2 years, late referrals require more complex reconstructions. Early recognition, steroid therapy and early referral for facial reanimation (when the diagnosis is secure) are important features of good management when encountering these complex cases.

Autoimmune recurrent facial palsy and bilateral sudden sensorineural hearing loss following Ramsay Hunt-like syndrome

OBJECTIVE

To describe the first published case of recurrent facial nerve palsy associated with bilateral sudden sensorineural hearing loss of autoimmune origin.

CASE REPORT

A 33-year-old male presented with acute facial palsy on the left following a vesicular herpetic eruption in the external ear canal on the same side. Serologic measurements demonstrated an elevation of IgM antibodies against herpes simplex virus but not for varicella-zoster virus, confirming a Ramsay Hunt-like syndrome due to herpes simplex virus. The following four months, the patient exhibited other three episodes of facial palsy, well responded to steroid treatment. During the clinical course, a sudden sensorineural hearing loss was also diagnosed, initially on the left side and then on both sides. The autoimmune markers such as the antinuclear antibody and the anti-gangliosides antibodies (anti-GM1, anti-GQ1b) were found positive. Despite steroid treatment, hearing did not show any improvement, remaining moderate on the right and severe on the left.

CONCLUSION

Recurrent facial nerve palsy and bilateral sudden sensorineural hearing loss could be the expression of autoimmune disturbances. The initial triggered factor could be the herpes simplex virus infection, such as a Ramsay Hunt-like syndrome.

Increased seroprevalence of Toxoplasma gondii in a population of patients with Bell's palsy: a sceptical interpretation of the results regarding the pathogenesis of facial nerve palsy

Facial nerve oedema and anatomical predisposition to compression within the fallopian tube seem to be the only generally accepted facts in the pathophysiology of Bell's palsy. Several infectious causes have been suggested as possible triggers of this oedema. Most of the suggested pathogens have been associated with facial nerve lesions during latent infections, reinfections or endogenous reactivations. The aim of this study was to investigate the seroprevalence of three such pathogens Toxoplasma gondii, Epstein-Barr virus (EBV) and cytomegalovirus (CMV) in a population of patients with facial nerve palsy. Fifty-six patients with Bell's palsy were included in the study. A group of 25 individuals with similar age and gender distribution was used as control. Seropositivity for T. gondii, EBV viral capsid antigen (VCA) and CMV-specific IgM and IgG antibodies was investigated 2-5 days after the onset of the palsy. Comparisons for both IgM and IgG antibodies against T. gondii attributed significantly higher seroprevalence in the patients' group than in the control group (p = 0.024 and 0.013, respectively). The respective examinations for EBV and CMV attributed no significant results. The roles of EBV and CMV in the pathogenesis of Bell's palsy were not confirmed by this study. However, a significantly higher seroprevalence of IgM- and IgG-specific T. gondii antibodies was detected in patients with Bell's palsy when compared to healthy controls. The possibility that facial nerve palsy might be a late complication of acquired toxoplasmosis may need to be addressed in further studies.

Practical management of Bell's palsy

Bell's palsy is an acute unilateral weakness or paralysis of the face resulting from peripheral facial nerve dysfunction. While there is no readily identifiable cause, there is some recovery of function within 6 months. This article offers practical guidelines for diagnosing and treating Bell's palsy. These guidelines are based on the author's experience with 63 patients over the last 8 years. Physical examination should reveal diffuse nerve involvement, normal otoscopic findings, and no skin blebs or blisters and parotid masses. Other cranial nerve palsies may be present. Diagnostic testing should include basic audiometry if available, and computed tomography or magnetic resonance imaging scanning if paralysis is present. Facial photography is recommended. Topognostic testing is not helpful because it no longer guides the surgical approach, and prognostic tests are not necessary if the face is not paralyzed. The only sufficiently sensitive test to determine the need for possible surgery is electroneurography. Eye care is critical in all but the mildest cases, and steroids may also be helpful. Surgery is rarely needed and should consist only of middle fossa total decompression; simple decompression of the tympanic and mastoid segments is seldom helpful. The natural history of the disease and the limited role of surgery provide new guidelines for practical management of Bell's palsy.