How to manage dysphagia in a patient with a medical history of myasthenia gravis (Myasthenia Gravis, MG)?

From the Guidelines

Managing dysphagia in patients with myasthenia gravis requires a multidisciplinary approach, focusing on optimizing the patient's myasthenia gravis treatment and addressing the swallowing difficulties, as recommended by the most recent guidelines 1.

Key Considerations

• Optimize the patient's myasthenia gravis treatment with acetylcholinesterase inhibitors like pyridostigmine and immunosuppressants such as prednisone, azathioprine, or mycophenolate mofetil as prescribed by their neurologist.
• Ensure medication timing is coordinated 30-45 minutes before meals to maximize muscle strength during eating.
• Dietary modifications are essential—recommend soft, moist foods and thickened liquids based on a speech-language pathologist's assessment, as supported by the ESPEN guideline on clinical nutrition in neurology 1.
• Patients should eat in an upright position, take small bites, and avoid fatigue by having multiple smaller meals throughout the day rather than three large ones.
• Swallowing techniques such as the chin tuck or head turn may help, as directed by a speech therapist.

Multidisciplinary Approach

• A multidisciplinary team approach, including a physician, nurse, speech-language pathologist, dietitian, and physical and occupational therapists, is crucial for managing dysphagia in patients with myasthenia gravis, as emphasized by the ACCP evidence-based clinical practice guidelines 1.
• The team should work together to assess the patient's nutritional needs, develop a personalized care plan, and provide education on dysphagia management.

Monitoring and Intervention

• Monitor for signs of aspiration pneumonia, including fever, cough, or respiratory distress.
• During myasthenic crisis, temporary nasogastric or percutaneous endoscopic gastrostomy (PEG) feeding may be necessary, as highlighted in the care of patients with acute ischemic stroke update 1.
• These interventions address the fundamental issue in MG dysphagia—weakness of bulbar and pharyngeal muscles due to antibody-mediated blockage of acetylcholine receptors at the neuromuscular junction, which impairs the coordinated muscle contractions needed for safe swallowing.

From the FDA Drug Label

Although failure of patients to show clinical improvement may reflect underdosage, it can also be indicative of overdosage. As is true of all cholinergic drugs, overdosage of pyridostigmine bromide may result in cholinergic crisis, a state characterized by increasing muscle weakness which, through involvement of the muscles of respiration, may lead to death Myasthenic crisis due to an increase in the severity of the disease is also accompanied by extreme muscle weakness, and thus may be difficult to distinguish from cholinergic crisis on a symptomatic basis For detailed information on the management of patients with myasthenia gravis, the physician is referred to one of the excellent reviews such as those by Osserman and Genkins2, Grob3 or Schwab4,5.

The management of dysphagia in a patient with a medical history of myasthenia gravis (MG) is not directly addressed in the provided drug label.

• The label discusses the warnings and usage of pyridostigmine bromide in patients with myasthenia gravis, but does not provide specific guidance on managing dysphagia.
• It recommends referring to external reviews for detailed information on managing patients with myasthenia gravis 2.

From the Research

Management of Dysphagia in Myasthenia Gravis

• Dysphagia is a common symptom in patients with myasthenia gravis (MG), caused by muscle weakness or fatigability in the pharynx, swallowing, and respiration discoordination 3.
• The current treatment for MG includes symptomatic and immunosuppressive/immunomodulatory treatment, with options such as corticosteroids, azathioprine, mycophenolate mofetil, and pyridostigmine 4, 5, 6.

Treatment Options for Dysphagia in MG

• Pyridostigmine is the most commonly used drug in the symptomatic treatment of MG, with a reported median effectiveness of 60 and net benefit of 65 6.
• However, pyridostigmine can cause side effects such as flatulence, urinary urgency, muscle cramps, blurred vision, and hyperhidrosis, with 91% of patients reporting side effects 6.
• Azathioprine and mycophenolate mofetil are also used as immunosuppressants in MG, with comparable effectiveness and adverse event profiles 7.

Quantitative Assessment of Dysphagia in MG

• A novel method for evaluating swallowing difficulty in patients with MG has been established, using ventilation patterns and submental surface electromyography (sEMG) activity of the swallowing reflex 3.
• This method can quantify the severity of pharyngeal muscle weakness/fatigability and can be used to assess the effectiveness of treatment for dysphagia in MG 3.

Considerations for Treatment

• The choice of treatment for dysphagia in MG should be guided by the severity of symptoms, patient co-morbidities, and the potential for adverse events 4, 5, 6.
• A comprehensive treatment plan should include a combination of symptomatic and immunosuppressive/immunomodulatory treatments, as well as regular monitoring of symptoms and adverse events 4, 5, 6.