Laryngeal stridor in myasthenia gravis

Dysphonia as a primary manifestation in myasthenia gravis (MG): a retrospective review of 7 cases among 1520 MG patients

Myasthenia gravis (MG) is an autoimmune disorder of neuromuscular transmission, usually recognized with ocular complaints or generalized muscle weakness. However, among the 1520 MG cases that had been diagnosed and treated in our hospital in the last 15 years (1990-2005), we have identified 7 MG patients whose initial and prominent complaint was dysphonia and all had been misdiagnosed elsewhere. The diagnoses were confirmed with fibrolaryngoscope and voice analysis employed before and after a positive neostigmine (anticholinesterase) test. Electromyography with repetitive stimulations, single-fiber electromyography, and laboratory and radiographic evaluations were also conducted for diagnosis. A surprisingly low seropositivity rate of anti-acetylcholine-receptor antibodies (1/7) and anti-MuSK (Muscle Specific Kinase) antibodies (0/6) were found in these dysphonia MG patients. A cholinesterase inhibitor (ChEI) and immunosuppressive therapy were applied for treatment. Extended thymectomy was applied to MG patients with thymus hyperplasia or thymic tumor. Significant improvement was found in all 7 cases after these treatments. We have developed a sere of diagnostic protocol for this rare type of laryngeal MG, and discussed the clinical implication of our data. In summary, dysphonia or laryngeal disorder can be the only prominent manifestation of MG in rare cases, which should be taken into consideration during the diagnosis to patients with exclusive laryngeal complaints.

Laryngeal Myasthenia Gravis: Report of 40 Cases

Myasthenia gravis, an autoimmune disorder of the neuromuscular junction, is usually recognized because of ocular complaints or generalized weakness. We report a series of 40 patients who presented with dysphonia as their initial and primary complaint. Diagnostic testing included strobovideolaryngoscopy, electromyography (EMG) with repetitive stimulation and Tensilon testing, and laboratory and radiographic evaluation. Strobovideolaryngoscopy most commonly revealed fluctuating impairment of vocal fold mobility, either unilateral or bilateral. EMG detected evidence of neuromuscular junction abnormalities in all patients. Only one patient had evidence of antiacetylcholine receptor (ACh-R) antibodies, but many other abnormalities suggestive of autoimmune dysfunction were present. Pyridostigmine therapy was initiated in 34 patients but was not tolerated in 4. Of the remaining 30 patients, 23 reported improvement of symptoms. We conclude that myasthenia gravis can present with symptoms confined primarily to the larynx and should be included in the differential diagnosis of dysphonia.

Posterior glottic stenosis and bilateral vocal fold immobility: diagnosis and treatment

Posterior glottic stenosis and bilateral vocal fold immobility cause obstruction of the airway at the glottis. Presentation of this problem may vary according to the cause. Full evaluation of the status of the larynx is crucial with regard to the mobility of the arytenoid cartilage and innervation of the laryngeal musculature. There are many techniques for surgically treating this condition, each with advantages and disadvantages. The surgeon should be familiar with a variety of these procedures and be able to adapt to each patient's situation.

Acute inspiratory stridor: a presentation of myasthenia gravis

We present a rare presentation of myasthenia gravis as acute inspiratory stridor in a 16-year-old girl. Prompt diagnosis and medical treatment avoided the need for tracheostomy. Although an uncommon cause, myasthenia gravis should be included in the differential diagnosis of stridor.

Bilateral abductor vocal fold paralysis due to myasthenia gravis

We report a case of bilateral abductor vocal fold paralysis due to myasthenia gravis in a 61-year-old man who presented with stridor requiring tracheostomy. The stridor had been preceded by several weeks' history of diplopia.

Idiopathic bilateral vocal fold weakness

OBJECTIVE

To describe an unrecognized clinical entity, idiopathic bilateral vocal fold weakness, and propose recommendations regarding the diagnosis and management of these cases.

STUDY DESIGN

Retrospective, nonrandomized case study.

METHODS

All cases of bilateral vocal fold weakness evaluated at the University of Washington Voice Disorders Clinic between 1991 to 1998 were reviewed.

RESULTS

Four patients with bilateral laryngeal weakness were determined to have idiopathic bilateral vocal fold paresis following exhaustive workups, including videostroboscopy, bilateral laryngeal electromyography (EMG), neurological consultation, and other pertinent studies.

CONCLUSIONS

Performing bilateral laryngeal EMG is an essential aspect of the workup of any laryngeal weakness case, particularly if the etiology is unknown on presentation. Idiopathic bilateral vocal fold weakness is an underrecognized but real clinical diagnosis that will become more familiar with the increasing utilization of laryngeal EMG in clinical situations.

Preoperative preparation and anesthetic management of patients with myasthenia gravis

Patients with myasthenia gravis have specific clinical problems that must be addressed by the anesthesiologist when surgery is contemplated. Optimal perioperative management of myasthenia gravis patients undergoing thymectomy requires careful preoperative assessment and preparation. This assessment and preparation includes evaluation for concomitant autoimmune, respiratory, and cardiac disorders as well as optimization of medical management for myasthenia. There are important intraoperative concerns to be addressed including appropriate monitoring, premedication, and other agents used during surgery including muscle relaxants and anesthetic agents. Postoperatively, attention must be directed specifically to pain relief, ventilatory management, and the appropriate titration of reversal agents and anticholinesterase inhibitors. Optimal management of all these factors maximizes the chance for successful and uncomplicated hospitalization.

Myasthenia gravis presenting with stridor

The case is described of a 72 year old woman who presented with a two year history of exertional stridor in whom the diagnosis of myasthenia gravis was delayed. Although an uncommon cause, myasthenia gravis should be included in the differential diagnosis of stridor.