Asymmetric pattern in generalized myasthenia gravis: A case report

Myasthenia gravis (MG) is an uncommon autoimmune disease mediated by antibodies that attack the postsynaptic acetylcholine receptors (AchRs) at the neuromuscular junction, causing fluctuating muscle weakness, aggravated with use, and relieved with rest. A 32-year-old woman with a diagnosis of MG based on clinical findings, eletroneuromyography, and brain magnetic resonance imaging (MRI) was admitted to our hospital with dysphagia, dysphonia, diplopia, and intense weakness, associated with a 2-day viral gastroenteritis. Physical examination revealed globally reduced deep tendon reflexes, and tetraparesis, with muscle strength grade 4 in the left limbs and grade 2 in the right limbs. Autoantibody dosing against AchR was elevated and computed tomography scan of the thorax revealed a thymic remnant. Pyridostigmine and human immunoglobulin were infused. After 7 days of the reintroduction of pyridostigmine and human immunoglobulin infusion, the patient developed complete resolution of symptoms, being discharged from the hospital. Her symptoms are still well controlled 6 months later. The patient was evaluated by a thoracic surgeon and is awaiting elective thymectomy. Although our patient presented all the diagnostic criteria of MG, the markedly asymmetric limb weakness presented in previous history and clinical examination of admission was an unusual and unexpected presentation, especially considering the pathophysiology of the disease. MRI of brain without abnormalities was fundamental to rule out another associated etiology. Our review of the literature revealed just 1 case report of MG with similar presentation. This clinical manifestation becomes valuable because it contributes to the list of unexpected presentation that should motivate its suspicion.