Myasthenic crisis

Abstract

Myasthenic crisis (MC) is a life‐threatening manifestation of myasthenia gravis (MG) defined by respiratory insufficiency that requires the use of invasive or non‐invasive ventilation. This is often the result of respiratory muscle weakness but can also be due to bulbar weakness with upper airway collapse. MC occurs in approximately 15%–20% of patients with MG usually within the first 2 to 3 y of the disease course. Many crises have a specific trigger with respiratory infections being most common; however, no specific trigger is found in 30%–40% of patients. MG patients with a history of MC, severe disease, oropharyngeal weakness, muscle‐specific kinase (MuSK) antibodies and thymoma appear to be at higher risk. Most episodes of MC do not occur suddenly, providing a window of opportunity for prevention. Immediate treatment is directed toward airway management and removing any identified triggers. Plasmapheresis is preferred over intravenous immune globulin as the treatments of choice for MC. The majority of patients are able to be weaned from mechanical ventilation within 1 mo and the outcomes of MC are generally favorable. The mortality rate in United States cohorts is less than 5% and mortality in MC seems to be driven by age and other medical co‐morbidities. MC does not appear to affect long‐term prognosis as many patients are able to eventually achieve good MG control.

Rescue treatment with add-on efgartigimod in a patient with impending myasthenic crisis: a case report

“…However, our patient received oral prednisone treatment for nearly 1 month before admission, which failed to prevent disease progression and she worsened again 10 days after infusion of IVIg and methylprednisolone in our center. Therefore, considering that most patients gain benefits from IVIg within 4–5 days and glucocorticoid often has an effect within 2–4 weeks in 75% of patient, 10 , 11 we believe that the rapid therapeutic effect of efgartigimod was an important reason for the significant improvement in this case.…”

Serum amyloid A facilitates expansion of CD4+ T cell and CD19+ B cell subsets implicated in the severity of myasthenia gravis patients

“…Myasthenic crisis (MC) represents a life‐threatening state with high mortality in MG, around 15%–20% of the patients may develop MC within the first 2–3 years of the disease course (Claytor et al., 2023). The prognostic factors for patients at risk of MC remain incompletely understood, but thymoma‐associated MG (TAMG) are believed to develop MC easily (Huan et al., 2023; Xue et al., 2017).…”

Case report: Recovery from refractory myasthenic crisis to minimal symptom expression after add-on treatment with efgartigimod

“…Improvement can typically be observed within the first 1 to 2 weeks after injection. Because of this relatively immediate effect, it is thought that efgartigimod may be effective against MC ( 1 ). Improvement in our patient’s MC was noted about 12 days after the first intravenous efgartigimod administration, suggesting the effectiveness of this therapy for MC.…”

“…Myasthenic crisis (MC) is the most severe, life-threatening manifestation of myasthenia gravis (MG), often requiring noninvasive and/or mechanical ventilation, supportive enteral feeding, and intensive care unit management ( 1 ). Disease-modifying treatments such as plasmapheresis and intravenous immunoglobulins (IVIG) can be administered in the management of MC, but these treatments are not effective in all patients.…”