Illuminating Myasthenia Gravis

By Dr Nicola Davies

Myasthenia Gravis (MG) is a rare long-term chronic autoimmune condition that affects the body’s voluntary muscles.1 It occurs when antibodies such as Immunoglobulin G (IgG) attack receptors that receive nerve impulses for the muscles, eventually leading to muscle weakness and fatigue. The cause of this autoimmune reaction is currently unknown, as MG is not hereditary and appears to develop spontaneously in individuals.

Muscles controlling leg and arm movements, the eyes and eyelids, speaking, facial expressions, chewing and swallowing are affected. As a result, individuals affected by MG can display symptoms such as drooping eyelids, double vision, impaired speech, dysphagia, weakness in upper arm and leg muscles, and excessive fatigue after physical activity.2 In some severe cases, life-threatening complications may arise due to autoimmune attacks on muscles involved in breathing. It is also believed the thymus gland plays a role in this condition, as over 75% of patients have distinct abnormalities in their thymus. 1