Myasthenia Gravis

Description

Diagnostic criteria

Medicine treatment

Referral

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G70.0

DESCRIPTION

An auto-immune disorder resulting in muscle fatigue. Mild cases involve the eyes alone, i.e. ptosis and ophthalmoplegia, and severe cases involve proximal muscle groups, respiratory and bulbar control.

DIAGNOSTIC CRITERIA

Clinical

• Muscle fatigability with exercise and demonstration of this in the clinic setting:
  • Lid-lag test, i.e. failure to maintain upward gaze for 1 minute.
  • Arm-raising test, i.e. failure to maintain the arms at 90° from the trunk for 1 minute.

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Note:

Myasthenia gravis patients not uncommonly present in a myasthenic crisis, with bulbar and respiratory compromise. Sometimes this may be the first mode of clinical presentation.

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MEDICINE TREATMENT

• Pyridostigmine, oral, 1–5 mg/kg/day in 4–6 divided doses. (Specialist initiated).

REFERRAL

• All for confirmation of diagnosis and initiation of treatment (consideration of steroids, immuno-modulation therapy).
• Myasthenic crisis.

Click here to access the pdf.

Click here to access NEMLC Report.

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Standard Treatment Guidelines and Essential Medicines List for South Africa, Paediatric Hospital Level_Updated May 2025

Chapter 13: The Nervous System_13.7 Neuromuscular Disorders_13.7.2 Myasthenia Gravis

Click here for 13.7.2.1 Myasthenic Crisis (MC)