AbstractAutoimmune disorders affecting the vestibular end organs, vestibular pathways, vestibular nuclei, and vestibulocerebellum are often underrecognized as a cause of chronic dizziness and ataxia. Autoantibodies specific for cell-surface, synaptic, and intracellular neural antigens serve as biomarkers of these disorders. This article describes the epidemiology, clinical presentation, diagnostic considerations, imaging findings, treatment, and prognosis of autoimmune disorders, in which the vestibulocerebellar syndrome is the main or presenting clinical presentation. Antibodies specific for intracellular antigenic targets described in the article are PCA-1 (Purkinje cell cytoplasmic antibody type 1, also known as anti-Yo), ANNA-1 (antinuclear neuronal antibody type 1, also known as anti-Hu), ANNA-2 (antinuclear neuronal antibody type 2, also known as anti-Ri), Ma1/2 (anti-Kelch-like 11/12 antibody), Kelch-like 11, amphiphysin, CV2 (collapsin response 2, also known as collapsin response mediator protein-5 [CRMP5]), VGCC (voltage-gated calcium channel), GAD65 (glutamic acid decarboxylase 65-kDa isoform), AP3B2 (adaptor protein 3B2, also known as anti-Nb), MAP1B (microtubule-associated protein 1B antibody, also known as anti-PCA-2), and neurochondrin antibodies. Antibodies targeting cell-surface or synaptic antigenic targets described in the article include DNER (delta/notchlike epidermal growth factor related receptor; antigen to anti-Tr), CASPR2 (contactin-associated proteinlike 2), septin-5, Homer-3, and mGluR1 (metabotropic glutamate receptor 1). The vestibulocerebellar presentation is largely indistinguishable among these conditions and is characterized by subacute onset of cerebellar symptoms over weeks to months. The diagnosis of autoimmune vestibulocerebellar syndromes is based on a combination of clinical and serological features, with a limited role for neuroimaging. Subtle eye movement abnormalities can be an early feature in many of these disorders, and therefore a meticulous vestibulo-ocular examination is essential for early and correct identification. Cancer occurrence and its type are variable and depend on the autoantibody detected and other cancer risk factors. Treatment comprises immunotherapy and cancer-directed therapy. Acute immunotherapies such as intravenous immunoglobulin, plasma exchange, and steroids are used in the initial phase, and the use of long-term immunosuppression such as rituximab may be necessary in relapsing cases. Outcomes are better if immunotherapy is started early. The neurologic prognosis depends on multiple factors.
Bilateral Vestibular Hypofunction in Neurosarcoidosis: A Case Report
We describe the case of a 59-year-old woman who presented with progressive bilateral vestibidar hypofunction and who was found to have bilateral granulomatous mass lesions of the mesial temporal lobe. Initially, her condition stabilized neurologically with corticosteroids, but a diagnosis of neurosarcoidosis was delayed because of the unusual presentation and persistently normal chest imaging results and serum angiotensin-converting enzyme (ACE) levels. Approximately 1 year after her initial presentation, the patient died of complications of a myocardial infarction and pulmonary embolism. Sarcoidosis should be considered in the differential diagnosis of idiopathic bilateral vestibular hypofunction even if the chest imaging and serum ACE levels are normal, particularly when there is evidence of a multisystem process.
Objective Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence‐based recommendations for the diagnosis, management, and follow‐up of patients who present with SHL. The guideline primarily focuses on sudden sensorineural hearing loss (SSNHL) in adult patients (aged 18 and older). Prompt recognition and management of SSNHL may improve hearing recovery and patient quality of life (QOL). Sudden sensorineural hearing loss affects 5 to 20 per 100,000 population, with about 4000 new cases per year in the United States. This guideline is intended for all clinicians who diagnose or manage adult patients who present with SHL. Purpose The purpose of this guideline is to provide clinicians with evidence‐based recommendations in evaluating patients with SHL, with particular emphasis on managing SSNHL. The panel recognized that patients enter the health care system with SHL as a nonspecific, primary complaint. Therefore, the initial recommendations of the guideline deal with efficiently distinguishing SSNHL from other causes of SHL at the time of presentation. By focusing on opportunities for quality improvement, the guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients. Results The panel made strong recommendations that clinicians should (1) distinguish sensorineural hearing loss from conductive hearing loss in a patient presenting with SHL; (2) educate patients with idiopathic sudden sensorineural hearing loss (ISSNHL) about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy; and (3) counsel patients with incomplete recovery of hearing about the possible benefits of amplification and hearing‐assistive technology and other supportive measures. The panel made recommendations that clinicians should (1) assess patients with presumptive SSNHL for bilateral SHL, recurrent episodes of SHL, or focal neurologic findings; (2) diagnose presumptive ISSNHL if audiometry confirms a 30‐dB hearing loss at 3 consecutive frequencies and an underlying condition cannot be identified by history and physical examination; (3) evaluate patients with ISSNHL for retrocochlear pathology by obtaining magnetic resonance imaging, auditory brainstem response, or audiometric follow‐up; (4) offer intratympanic steroid perfusion when patients have incomplete recovery from ISSNHL after failure of initial management; and (5) obtain follow‐up audiometric evaluation within 6 months of diagnosis for patients with ISSNHL. The panel offered as options that clinicians may offer (1) corticosteroids as initial therapy to patients with ISSNHL and (2) hyperbaric oxygen therapy within 3 months of diagnosis of ISSNHL. The panel made a recommendation against clinicians routinely prescribing antivirals, thrombolytics, vasodilators, vasoactive substances, or antioxidants to patients with ISSNHL. The panel made strong recommendations against clinicians (1) ordering computerized tomography of the head/brain in the initial evaluation of a patient with presumptive SSNHL and (2) obtaining routine laboratory tests in patients with ISSNHL.
Clinical Practice Guideline: Benign Paroxysmal Positional Vertigo
Objectives:This guideline provides evidence‐based recommendations on managing benign paroxysmal positional vertigo (BPPV), which is the most common vestibular disorder in adults, with a lifetime prevalence of 2.4 percent. The guideline targets patients aged 18 years or older with a potential diagnosis of BPPV, evaluated in any setting in which an adult with BPPV would be identified, monitored, or managed. This guideline is intended for all clinicians who are likely to diagnose and manage adults with BPPV.Purpose:The primary purposes of this guideline are to improve quality of care and outcomes for BPPV by improving the accurate and efficient diagnosis of BPPV, reducing the inappropriate use of vestibular suppressant medications, decreasing the inappropriate use of ancillary tests such as radiographic imaging and vestibular testing, and to promote the use of effective repositioning maneuvers for treatment. In creating this guideline, the American Academy of Otolaryngology—Head and Neck Surgery Foundation selected a panel representing the fields of audiology, chiropractic medicine, emergency medicine, family medicine, geriatric medicine, internal medicine, neurology, nursing, otolaryngology–head and neck surgery, physical therapy, and physical medicine and rehabilitation.ResultsThe panel made strong recommendations that 1) clinicians should diagnose posterior semicircular canal BPPV when vertigo associated with nystagmus is provoked by the Dix‐Hallpike maneuver.The panel made recommendations against 1) radiographic imaging, vestibular testing, or both in patients diagnosed with BPPV, unless the diagnosis is uncertain or there are additional symptoms or signs unrelated to BPPV that warrant testing; and 2) routinely treating BPPV with vestibular suppressant medications such as antihistamines or benzodiazepines.The panel made recommendations that 1) if the patient has a history compatible with BPPV and the Dix‐Hallpike test is negative, clinicians should perform a supine roll test to assess for lateral semicircular canal BPPV; 2) clinicians should differentiate BPPV from other causes of imbalance, dizziness, and vertigo; 3) clinicians should question patients with BPPV for factors that modify management including impaired mobility or balance, CNS disorders, lack of home support, and increased risk for falling; 4) clinicians should treat patients with posterior canal BPPV with a particle repositioning maneuver (PRM); 5) clinicians should reassess patients within 1 month after an initial period of observation or treatment to confirm symptom resolution; 6) clinicians should evaluate patients with BPPV who are initial treatment failures for persistent BPPV or underlying peripheral vestibular or CNS disorders; and 7) clinicians should counsel patients regarding the impact of BPPV on their safety, the potential for disease recurrence, and the importance of follow‐up.The panel offered as options that 1) clinicians may offer vestibular rehabilitation, either self‐administered or with a clinician, for the initial treatment of BPPV and 2) clinicians may offer observation as initial management for patients with BPPV and with assurance of follow‐up.The panel made no recommendation concerning audiometric testing in patients diagnosed with BPPV.Disclaimer:This clinical practice guideline is not intended as a sole source of guidance in managing benign paroxysmal positional vertigo. Rather, it is designed to assist clinicians by providing an evidence‐based framework for decision‐making strategies. The guideline is not intended to replace clinical judgement or establish a protocol for all individuals with this condition, and may not provide the only appropriate approach to diagnosing and managing this problem. ® 2008 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved.