Peter Špalek
Myasthenia gravis (MG) is an autoimmune disorder caused by autoantibodies against antigens at postsynaptic
motor end-plate of neuromuscular junction causing failure of neuromuscular transmission. MG presents clinically by
muscle weakness and fatiguability, and respiratory and bulbar insuficiency may threaten patient’s life. Intravenous
immunoglobulin (IVIg) has a rapid and intensive immunosupressive effect and good safety profil with minimum side
effects.
Therefore IVIG as intervention immunotherapy is a first-line treatment in patients with myasthenic crises and acute
severe generalised MG with bulbar and/or respiratory insufficiency. IVIG in these indication has to be applied at
a dosage of 0,4 g/day/kg body weight on 5 consecutive days. To secure long-term improvement, IVIG is combined
with standard immunosuppressive drugs (usually prednisone and azathioprine) in higher doses. Comparing to plasma
exchange IVIG is more convient because of its direct influence on autoantibodies production, lower risk of severe
side-effects and IVIG can be safely used during pregnancy. Plasma exchange has high risk of side-effects
in myasthenics with inflammatory complications and in myasthenic crisis with sepsis plasma-exchange is absolutely
contraindicated. IVIG can also be used also as chronic-intermittent maintenance therapy in single patients
with therapy (corticosteroids, azathioprin) resistent myasthenic symptoms. Chronic-intermittent IVIG maintenance
treatment may also be used in rare MG patients with contraindications against other immunosuppressive agents.