ABSTRACT
Myasthenia gravis (MG) is an acquired autoimmune disorder characterized by fatigable and fluctuating muscle weakness preferentially affecting certain muscle groups. In most cases, it results from serum antibodies targeting the acetylcholine receptors on the postsynaptic membrane of the neuromuscular junction. Treatment of MG consists of symptomatic control with cholinesterase inhibitors and immunotherapies. Myasthenic crisis is respiratory failure as a result of severe respiratory muscle weakness requiring intubation and mechanical ventilation. Chest computed tomography or magnetic resonance imaging should be done in every MG patient to evaluate for the presence of thymoma. Plasma exchange is mainly used in patients who are in crisis, prior to thymectomy or in combination with high-dose corticosteroids to prevent a steroid-induced exacerbation. Congenital myasthenic syndrome is a heterogeneous group of disorders caused by various genetic mutations resulting in failed neuromuscular transmission. Botulism is caused by neurotoxins released by Clostridium botulinum, a gram-positive, spore-forming anaerobic bacterium.
