Patient: [Patient Name]
MRN: [Medical Record Number]
Date: [Date of Encounter]
Chief Complaint:
New diagnosis of myasthenia gravis (MG) OR follow-up for established MG
(Specify) Symptoms vary depending on the affected muscle groups. Common complaints include:
Ptosis (drooping eyelids)
Diplopia (double vision)
Dysarthria (slurred speech)
Dysphagia (difficulty swallowing)
Facial weakness
Proximal muscle weakness (weakness in shoulders, hips, and thighs)
Respiratory weakness (severe cases)
History of Present Illness:
Onset, duration, and severity of symptoms. Progression of weakness is a hallmark feature of MG.
For established MG:
Date of diagnosis and prior treatment history.
Response to previous treatments (improvement or worsening of symptoms).
Any new or worsening symptoms.
Exacerbating or relieving factors (e.g., infections, medications, stress).
Past Medical History:
Underlying medical conditions (e.g., thymus hyperplasia or thymoma).
History of autoimmune diseases (may suggest increased risk of MG).
Surgical history (prior thymectomy may have been performed).
Family History:
Family history of MG (uncommon).
Medications:
List all current medications, including:
Acetylcholinesterase inhibitors (e.g., pyridostigmine) – mainstay of treatment for MG.
Immunosuppressive medications (e.g., azathioprine, mycophenolate) – used to suppress antibody production.
Corticosteroids (prednisone) – may be used in severe cases or for short-term management.
Social History:
Assess impact of MG on daily activities, work, and quality of life.
Social support system (important for managing chronic illness).
Physical Exam:
General examination: Look for signs of ptosis, diplopia, facial weakness, and respiratory distress.
Neurological examination: Evaluate muscle strength in different muscle groups, assess for reflexes, and perform cranial nerve testing (focus on ptosis, diplopia, and dysarthria).
Laboratory Tests:
Anti-acetylcholine receptor antibody (AchR Ab) testing: Positivetest in approximately 80% of generalized MG cases. Negative test does not rule out MG.
Muscle-specific tyrosine kinase antibody (MuSK Ab) testing: Positive test suggests ocular myasthenia gravis (limited to eye muscles).
Imaging Studies:
Chest X-ray: May be used to assess for signs of lung involvement (rare in MG).
CT scan or MRI of the chest: May be used to evaluate the thymus gland for enlargement (thymoma).
Electrodiagnostic Testing:
Repetitive nerve stimulation (RNS) test: Measures the electrical response of muscles after repeated nerve stimulation. Decreased response suggests impaired neuromuscular transmission characteristic of MG.
Assessment:
Myasthenia gravis: Based on clinical presentation (characteristic weakness, ptosis, diplopia) and supportive laboratory or electrodiagnostic testing.
Disease severity: Classified based on the affected muscle groups and severity of symptoms. Generalized MG involves multiple muscle groups, while ocular MG is limited to the eye muscles.
Differential Diagnoses:
Consider other conditions that can cause similar symptoms:
Congenital myopathies
Lambert-Eaton syndrome (paraneoplastic syndrome associated with certain cancers)
Stroke
Brain tumors
Plan:
Treatment:
Acetylcholinesterase inhibitors: The mainstay of treatment, medications like pyridostigmine increase the availability of acetylcholine at the neuromuscular junction, improving muscle strength.
Immunosuppressive medications: Used to suppress the immune response that produces antibodies against the acetylcholine receptor. May take weeks or months to show benefit.
Plasma exchange or intravenous immune globulin (IVIG): Used in severe cases or for rapidly worsening symptoms to remove harmful antibodies from the circulation.
Thymectomy: Surgical removal of the thymus gland may be recommended, especially in younger patients with generalized MG and evidence of thymus hyperplasia or thymoma.