What is the diagnosis and treatment for a patient with bilateral sensorineural deafness, progressive neuromuscular weakness, and swallowing difficulties?

Diagnosis: Brown-Vialetto-Van Laere Syndrome (BVVL)

This clinical triad of bilateral sensorineural deafness, progressive neuromuscular weakness, and swallowing difficulties in a young patient is pathognomonic for Brown-Vialetto-Van Laere syndrome, a rare progressive pontobulbar palsy with deafness. 1

Clinical Presentation and Diagnostic Features

The constellation of symptoms described represents a classic presentation of BVVL syndrome, characterized by:

• Bilateral sensorineural hearing loss occurring early in disease course (typically adolescence) 1
• Progressive bulbar palsy manifesting as dysphagia and dysarthria 1, 2
• Progressive limb weakness and atrophy affecting both proximal and distal muscles 1
• Multiple cranial nerve involvement (particularly cranial nerves III, VII, X, XI, XII) 1

Key Distinguishing Features

The bilateral nature of the hearing loss with concurrent progressive neuromuscular symptoms immediately excludes idiopathic sudden sensorineural hearing loss. 3 Bilateral sudden hearing loss is rare and demands investigation for serious underlying systemic, autoimmune, metabolic, infectious, neoplastic, toxic, traumatic, or inflammatory causes. 3

The presence of focal neurologic findings (weakness, dysarthria, dysphagia) alongside bilateral sensorineural hearing loss indicates this is NOT idiopathic SSNHL but rather a defined neurological syndrome. 3

Essential Diagnostic Workup

Immediate Audiological Assessment

• Comprehensive audiometry to confirm bilateral sensorineural hearing loss (≥30 dB loss at 3 consecutive frequencies) 4, 5
• Auditory brainstem response (ABR) typically shows no response in BVVL syndrome 1

Neurological Evaluation

• MRI brain with internal auditory canal sequences (with gadolinium) to exclude retrocochlear pathology such as vestibular schwannoma or brainstem lesions 4, 5
  • In BVVL, MRI typically shows no high signal in pyramidal tracts on FLAIR imaging 1
• Complete neurologic examination documenting cranial nerve palsies, limb weakness patterns, deep tendon reflexes, and bulbar function 1, 2

Electrophysiological Studies

• Electromyography (EMG) reveals neurogenic changes in BVVL 1
• Nerve conduction studies are typically normal 1
• Visual evoked potentials (VEP) may show P100 delay 1

Respiratory Assessment

• Pulmonary function testing including vital capacity measurement, as respiratory compromise is a critical complication 1
• Arterial blood gas analysis to detect CO2 retention and respiratory failure 1

Additional Testing

• Cerebrospinal fluid examination if infectious or inflammatory causes suspected 2
• Muscle enzymes, thyroid screening, vitamin B12, anti-acetylcholine receptor antibodies to exclude myopathy, myasthenia gravis, and metabolic causes 2
• Muscle biopsy in select cases if diagnosis remains uncertain 2

Treatment Approach

Respiratory Management (Priority for Mortality)

Respiratory failure is the primary cause of mortality in BVVL syndrome and requires aggressive monitoring and intervention. 1

• Non-invasive ventilation (BiPAP) initially, particularly during sleep when apnea and CO2 retention occur 1
• Mechanical ventilation via tracheostomy for progressive respiratory failure 1
• Serial monitoring of vital capacity and blood gases 1

Dysphagia Management (Priority for Morbidity)

Untreated neurogenic dysphagia leads to dehydration, malnutrition, aspiration pneumonia, and respiratory complications. 2

• Videofluoroscopy of swallowing to assess oropharyngeal motor performance and laryngeal protection 2
• Modified diet consistency and swallowing therapy if oral feeding is reasonably safe 2, 3
• Gastrostomy tube placement when oral feeding becomes unsafe or inadequate to prevent aspiration and maintain nutrition 2

Hearing Rehabilitation

• Hearing aids for residual hearing 6
• Cochlear implantation consideration, though limited benefit given progressive neurological nature 6
• Communication strategies and assistive listening devices 3

Supportive Care

• Physical therapy to maintain mobility and prevent contractures 1
• Speech therapy for dysarthria and communication strategies 3, 2
• Nutritional support via enteral feeding when necessary 2

Critical Pitfalls to Avoid

Do not mistake this for idiopathic sudden sensorineural hearing loss and treat with corticosteroids alone. 3, 5 While steroids may be appropriate for autoimmune causes of bilateral hearing loss 3, BVVL syndrome requires comprehensive neurological management focused on preventing respiratory failure.

Do not delay respiratory assessment. 1 Patients may develop CO2 narcosis and require urgent ventilatory support. Serial pulmonary function testing is essential.

Do not assume dysphagia is compensated. 2 The laryngeal cough reflex may be diminished, masking aspiration risk. Videofluoroscopy is mandatory before continuing oral feeding.

Prognosis and Long-term Management

BVVL syndrome is progressive and ultimately fatal without aggressive supportive care. 1 The disease slowly progresses over years to decades, with patients eventually requiring:

• Full-time mechanical ventilation 1
• Complete enteral nutrition 2
• Total communication assistance 1

Quality of life depends entirely on early recognition, proactive respiratory support, safe feeding strategies, and comprehensive multidisciplinary care. 1, 2