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Myasthenia gravis (MG) is an autoimmune disease which can impact pregnancy. We describe a transient neonatal myasthenia gravis (TNMG) born to an asymptomatic mother aged 26. The newborn presented cyanosis and generalized muscular weakness quickly after birth. Nasal continuous positive airway pressure (nCPAP) ventilation was performed immediately. On day 3, detailed family history showed that the neonate's 50-year-old maternal grandmother was diagnosed as ocular MG at the age of 40. Ryanodine receptor calcium release channel antibody (RyR-Ab) and acetylcholine receptor antibody (AChR-Ab) tested on day 5 were positive. However, neostigmine tests were negative for the neonate. Intravenous immunoglobulin (IVIG) and oral pyridostigmine were administered. The infant was weaned from the ventilator on day 7. On day 10, the neonate's asymptomatic mother was confirmed to have positive AChR-Ab either. The neonate regained the capability of bottle feeding on day 17 and discharged on day 26. Asymptomatic pregnant women with MG family history can also deliver infants who develop TNMG. Testing AChR antibodies in pregnant women with a family history of MG should be necessary as TNMG was a life-threatening disease. With timely diagnosis and accurate treatment, TNMG can be effectively relieved.

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PURPOSE: Myasthenia gravis (MG) is a rare, potentially life-threatening autoimmune disease with fluctuating muscle weakness frequently affecting women of childbearing age. MG can affect maternal as well as neonatal outcome with risk of worsening of myasthenic symptoms in the mothers and risk of transient neonatal myasthenia gravis (TNMG) and arthrogryposis multiplex congenita (AMC) or foetal acetylcholine receptor antibody-associated disorders (FARAD) in the neonates. METHODS: Retrospective analysis of maternal and neonatal outcome in a cohort of pregnant MG patients treated at a tertiary care centre in Germany. RESULTS: Overall, 66 pregnancies were analysed. During 40 (63%) pregnancies, women experienced a worsening of myasthenic symptoms, of whom 10 patients (15.7%) needed acute therapy with IVIg or plasma exchange. There was no case of myasthenic crisis. Rate of caesarean section was comparable to the overall C-section rate at our centre (38% vs. 40%). However, there was a slightly higher rate for operative vaginal delivery (15% vs. 10%) as potential indicator for fatiguing striated musculature in MG patients during the expulsion stage. Rate of TNMG as well as AMC was 3% (two cases each). CONCLUSIONS: Maternal and neonatal outcome in our cohort was favourable with a low rate of myasthenic exacerbations requiring acute therapies and a low rate of TNMG and AMC/FARAD. Our data might help neurologists and obstetricians to advice MG patients with desire to have children.

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BACKGROUND: There is evidence that gender-specific differences can influence the diagnostics, treatment and long-term disease course of myasthenia gravis (MG). In women the diagnosis is often made during childbearing age. OBJECTIVE: Gender-specific differences in MG and relevant aspects in routine clinical practice are presented. In addition, current studies on family planning, pregnancy and childbirth in MG are highlighted and treatment recommendations are derived. MATERIAL AND METHODS: Narrative literature review. RESULTS: In addition to sociodemographic data, gender-specific differences encompass clinical as well as paraclinical factors, such as disease severity and antibody status. With few exceptions pregnancy is possible with good maternal and neonatal outcome. During pregnancy and peripartum, children of MG patients should be closely monitored for early detection and treatment of potential syndromes caused by diaplacental transfer of maternal antibodies. CONCLUSION: Gender-specific factors can influence the course of MG. Adequate medical counselling and multidisciplinary collaboration are essential for MG patients who wish to have children.

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Transient neonatal myasthenia gravis (TNMG) is a neuromuscular disorder that occurs in infants born from mothers with myasthenia gravis (MG) due to transplacental transfer of antibodies against the acetylcholine receptor. TNMG is a rare form occurring in 10-15% of infants born from mothers with MG. We present a case of a newborn with TNMG with generalized hypotonia and respiratory distress. The newborn shows symptoms of hypotonia, weakened reflexes, poor crying, difficult sucking and potentiated tachydyspnea after 24 hours of birth and needs of assisted mechanical ventilation. Based on the mother's positive history of MG and the high titer of mother's (8.43nmol/l) and newborn's (9.088nmol/l) anti-AChR antibodies, TNMG was diagnosed. The baby was treated with assisted mechanical ventilation and neostig-mine until the anti-AChR antibody titer was negative. Adequate management of the newborn resulted in a positive outcome and evident withdrawal of the symptoms. Although TNMG is one of the rare neuromuscular disorders in newborns that can be treated, a multidisciplinary approach in the management of pregnant women with MG and newborns through timely diagnosis and early appropriate treatment, results in successful resolution of this condition.

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In utero exposure to maternal antibodies targeting the fetal acetylcholine receptor isoform (fAChR) can impair fetal movement, leading to arthrogryposis multiplex congenita (AMC). Fetal AChR antibodies have also been implicated in apparently rare, milder myopathic presentations termed fetal acetylcholine receptor inactivation syndrome (FARIS). The full spectrum associated with fAChR antibodies is still poorly understood. Moreover, since some mothers have no myasthenic symptoms, the condition is likely underreported, resulting in failure to implement effective preventive strategies. Here we report clinical and immunological data from a multicentre cohort (n = 46 cases) associated with maternal fAChR antibodies, including 29 novel and 17 previously reported with novel follow-up data. Remarkably, in 50% of mothers there was no previously established myasthenia gravis (MG) diagnosis. All mothers (n = 30) had AChR antibodies and, when tested, binding to fAChR was often much greater than that to the adult AChR isoform. Offspring death occurred in 11/46 (23.9%) cases, mainly antenatally due to termination of pregnancy prompted by severe AMC (7/46, 15.2%), or during early infancy, mainly from respiratory failure (4/46, 8.7%). Weakness, contractures, bulbar and respiratory involvement were prominent early in life, but improved gradually over time. Facial (25/34; 73.5%) and variable peripheral weakness (14/32; 43.8%), velopharyngeal insufficiency (18/24; 75%) and feeding difficulties (16/36; 44.4%) were the most common sequelae in long-term survivors. Other unexpected features included hearing loss (12/32; 37.5%), diaphragmatic paresis (5/35; 14.3%), CNS involvement (7/40; 17.5%) and pyloric stenosis (3/37; 8.1%). Oral salbutamol used empirically in 16/37 (43.2%) offspring resulted in symptom improvement in 13/16 (81.3%). Combining our series with all previously published cases, we identified 21/85 mothers treated with variable combinations of immunotherapies (corticosteroids/intravenous immunoglobulin/plasmapheresis) during pregnancy either for maternal MG symptom control (12/21 cases) or for fetal protection (9/21 cases). Compared to untreated pregnancies (64/85), maternal treatment resulted in a significant reduction in offspring deaths (P < 0.05) and other complications, with treatment approaches involving intravenous immunoglobulin/ plasmapheresis administered early in pregnancy most effective. We conclude that presentations due to in utero exposure to maternal (fetal) AChR antibodies are more common than currently recognized and may mimic a wide range of neuromuscular disorders. Considering the wide clinical spectrum and likely diversity of underlying mechanisms, we propose 'fetal acetylcholine receptor antibody-related disorders' (FARAD) as the most accurate term for these presentations. FARAD is vitally important to recognize, to institute appropriate management strategies for affected offspring and to improve outcomes in future pregnancies. Oral salbutamol is a symptomatic treatment option in survivors.

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Myasthenia gravis (MG) is an autoimmune condition, that commonly impacts adult women of reproductive age. Myasthenia gravis in pregnancy is rare, but the incidence is higher in different geographical areas. Pregnancies in mothers with MG can have an unfortunate outcome. Acetylcholine receptor antibodies may pass into the fetal circulation and can affect the fetal neuromuscular junction, generating transient MG or even fetal arthrogryposis. The 2016 and 2021 International Consensus Guidance for Management of Myasthenia Gravis issued by Myasthenia Gravis Foundation of America is lacking in recommendation for fetal surveillance for pregnancies in women with MG. The aim of this paper is to highlight fetal and neonatal complications in mothers with MG and to offer antenatal care insights. Close maternal and pregnancy monitoring can improve pregnancy outcome. Patients with MG should be encouraged to conceive, to avoid triggers for exacerbations of the disease during pregnancy and a multidisciplinary team should be established to ensure the optimal support and therapy.

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Myasthenia gravis (MG) in the neonate is usually due to placentally transferred antibodies to the acetylcholine receptor (AChR), resulting in impaired neuromuscular transmission. It occurs in 10%-15% of newborns born to women with MG. We present a male newborn admitted to the neonatal intensive care unit (NICU) 38 hours after birth due to feeding difficulties and choking episodes. He was born to a mother with MG after an uneventful, well-followed pregnancy. Physical examination revealed a weak cry, persistent inability to fully close his eyelids, weak facial mimic, and a mouth that was always held open with swallowing and sucking difficulties. He assumed a frog leg position and showed generalized hypotonia with marked head lag. No respiratory distress was present. Laboratory evaluation showed an elevated anti-acetylcholine receptor antibody concentration (36.30 nmol/L; normal: <0.25 nmol/L). Transient neonatal myasthenia gravis (TNMG) was admitted, and an anticholinesterase agent was initiated. Given that he showed only a mild clinical improvement, two doses of immunoglobulin were administered on the eighth and ninth days of life. Anticholinesterase agents were progressively reduced and suspended on day 31 of life with clinical improvement. He was discharged home at one month of life clinically asymptomatic. He was evaluated one month later and was doing well. A positive history of MG in the mother associated with a suggestive physical examination may be sufficient to make the diagnosis of transient neonatal MG, emphasizing the importance of good medical history. With prompt diagnosis and appropriate management, most newborns experience spontaneous remission after a period of weeks to months.

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A 31-year-old woman presented with a nasal voice, dysarthria, and upper limb weakness during her first pregnancy. Soon after delivery of her first baby, her symptoms disappeared. At the age of 34 years, during her second pregnancy, her nasal voice re-appeared. After delivery of the second baby, her nasal voice worsened, and bilateral eyelid ptosis and easy fatigability were also evident. She was referred to our hospital. Because of her myasthenic symptoms and anti-muscle-specific tyrosine kinase (MuSK) antibody (Ab)-positive status, she was diagnosed as having myasthenia gravis (MG). Her symptoms were worse than those in her first pregnancy. She was treated with oral steroid and double filtration plasmapheresis. After initiation of treatment, her myasthenic symptoms improved completely. In addition, her baby developed transient neonatal MG (TNMG) on the fourth day after birth and then gradually recovered over 30 days. It should be noted that symptoms of patients with anti-MuSK Ab-positive MG (MuSK-MG) can deteriorate during pregnancy, and the babies delivered of patients with MuSK-MG have a high probability of developing TNMG.

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We describe a 27-year-old pregnant female with new onset of conjugate gaze deficit during the third trimester of pregnancy. Repetitive nerve stimulation tests, neostigmine tests, and acetylcholine receptor antibody assays were all negative. The patient delivered a normal healthy baby at a local clinic via cesarean section. The baby became hypotonic and had respiratory failure several minutes after birth. The result of acetylcholine receptor antibody was negative in the neonate. The neonate became healthy spontaneously and was extubated after 21 days of ventilation care. Two months after delivery, the mother developed ptosis and generalized symptoms and subsequent workup revealed she was muscle specific kinase (MuSK) antibody positive. The neonate was presumed to have an anti-MuSK-mediated transient neonatal myasthenia gravis. Although MuSK antibody testing is rarely indicated in ocular myasthenia gravis, MuSK antibody testing is necessary in pregnant women who are presumed ocular myasthenia gravis to warn occurrence of transient neonatal myasthenia gravis.

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Background Myasthenia gravis (MG) is an autoimmune disorder with fluctuating muscle weakness, divided into generalized and localized (ocular) forms. Maternal antibodies to acetylcholine receptors cross the placenta and may cause transient neonatal myasthenia gravis (TNMG). We present a case of seronegative maternal ocular MG and delayed TNMG. Case A 29-year-old G3P1011 underwent cesarean birth of a male infant who developed oxygen desaturation requiring supplemental oxygen on day of life (DOL) 3. Based on the clinical course and after exclusion of other diagnoses, the infant was diagnosed with TNMG. Infant's condition improved spontaneously and he was weaned off supplemental oxygen and discharged home on DOL 12. Conclusion Infants born to mothers with seronegative localized (ocular) MG are also susceptible to TNMG which may be late in onset.

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Myasthenia gravis is a autoimmune neuromuscular disorder characterized by weakness and fatigability of skeletal muscles. The underlying defect is a decrease in the number of available acetylcholine receptors at neuromuscular junction due to an antibody-mediated autoimmune attacks. The course of myasthenia gravis during pregnancy is not predictable. We experienced a patient of myasthenia gravis associated with pregnancy who underwent cesarean section and transient neonatal myasthenia gravis of the newborn. We present this case with brief review of the concerned literatures.

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