Myasthenia Gravis Crisis

Abstract

Myasthenia gravis (MG) is an autoimmune disorder resulting from the production of antibodies against acetylcholine receptors leading to the destruction of the postsynaptic membrane at the neuromuscular junction. In the US there are about 18,000 people with MG. Myasthenia gravis crisis (MGC) is defined as any MG exacerbation necessitating mechanical ventilation. Most patients presenting with MGC have an identifiable risk factor. The diagnosis of MGC should be suspected in all patients with respiratory failure, particularly those with unclear etiology. Acute management of MGC requires supportive general and ventilatory therapy and institution of measures to improve the neuromuscular blockade. The latter includes plasma exchange or i.v. immunoglobulin, and removal of the offending trigger. The outcome of patients with MGC has improved significantly and the current mortality rate is about 4 to 8%.

The myasthenic patient in crisis: an update of the management in Neurointensive Care Unit

“…Patients who develop MC in their great majority have a precipitating factor, although, in 30-40% of cases, none is found 2,[5][6][7][9][10][11][12]19,21 . Respiratory infection (40%), emotional stresses, microaspirations (10%), changes in medication regimen (8%), surgery, or trauma are among the most common predisposing factors 2,[5][6][7][9][10][11][12]16,18 .…”

“…should be considered in MC 2,[4][5][6][7][8][9][10][11][12]18 . Although there is no universally accepted definition, MC should be considered a true neurological emergency characterized by "Severe weakness of the bulbar (innervated by cranial nerves) and/or respiratory muscles, enough to cause inability to maintain adequate ventilation and/or permeability of upper airways, causing respiratory failure that requires artificial airway or ventilatory support" 2,6 .…”

Myasthenia Gravis Presenting Initially as Acute Respiratory Failure

“…The weakness typically worsens with prolonged activity and improves with rest. 7 Isolated ocular muscle involvement is the most common presentation of MG, but weakness can also arise in bulbar or other muscles. There are few reports of acute respiratory failure as an initial presentation of MG. 10,11 The progression of respiratory failure in this case was much more acute than that of previous reports.…”

“…[2][3][4][5] The clinical courses of patients with MG are quite diverse, from complete remission to MGrelated death. 6 MG crisis, defined as an exacerbation of MG requiring ventilatory assistance, is a potentially fatal complication of MG. 7 MG crisis occurs in ϳ20% of patients with MG and usually during the first 2 y of illness. 8,9 Weakness in certain skeletal muscles, including ocular, bulbar, and limb muscles, is typically the initial symptom of MG.…”

A diagnosis of late-onset Myasthenia gravis unmasked by topical antibiotics

“…Antibiotics commonly associated to exacerbating myasthenia symptoms include fluroqinolones, aminoglycosides, macrolides, and beta-lactams. [2,3] We present a case of an elderly female with newly diagnosed MG following the use of tobramycin eye drops for 3 days.…”