Diaphragmatic myasthenia in mother and child

Abstract

Summary:A 28 year old patient with ocular myasthenia for 2y gave birth to a baby with diaphragmatic weakness. Following delivery the mother developed severe weakness of the diaphragm and required assisted ventilation. The baby recovered spontaneously and the mother responded to treatment with plasma exchange and immunosuppression. Neither mother nor baby responded to anticholinergic drugs and in neither serum were acetyl choline receptor antibodies detected.

Caesarean section in a patient with Myasthenia Gravis: A bigger challenge for the anesthesiologist than the obstetrician

“…[8] The worsening of symptoms has been reported to occur in first trimester by some, [8,9] in second trimester by a few, [10] while others have reported it in third trimester. [11,12] Our patient had disease exacerbation in the early postpartum period resembling the observations of Plauche [13] and Mier et al [14] It is recommended that anticholinesterase therapy be continued orally throughout the period of pregnancy. However, erratic gastric absorption during labor may necessitate a shift to equivalent intramuscular dosages.…”

Diagnostic difficulties in myasthenia gravis

“…13 Patients who lack anti-AChR antibodies may have antiAChR antibodies which are nondetectable, or they may have antibodies which bind to non-AChR determinants at the neuromuscular junction. 9,11 It is possible that the absence of anti-AChR antibodies in patients with myasthenia gravis represents a distinct disorder, and perhaps explains the occurrence of muscle weakness largely isolated to respiratory muscles and atypical electrophysiological findings in the 4 cases presented. In support of this view, a series of 8 seronegative patients with myasthenia gravis found a tendency for muscle weakness to primarily affect bulbar and respiratory muscles, with relative sparing of other muscles, and only 3 of the 8 patients had positive decremental responses.…”

AChR phosphorylation and indirect inhibition of AChR function in seronegative MG

“…They respond to plasmapheresis, 5 and babies born to affected mothers can have transient neonatal myasthenia. 6 Moreover, their plasmas injected into mice transfer a myasthenic disorder characterized by reduced miniature endplate potential ampli-tudes but without evidence of antibody bound to the AChRs. 7,8 Some patients with SNMG have a serum IgG antibody that binds to a cell surface protein present on the muscle-like cell line TE671 but not to the AChR itself, 9 and these patients have antibodies to the muscle-specific kinase, MuSK.…”