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Background and Purpose: Few large-scale studies examine whether maternal myasthenia gravis (MG) is a risk factor for complications during pregnancy and childbirth. This study evaluated whether maternal MG is associated with an increased risk of adverse pregnancy, delivery, and neonatal outcomes.

Methods: We conducted a nationwide Swedish register-based cohort study of women who gave birth to singleton infants (>= 22 gestational weeks) during 1987-2019. Exposed women were diagnosed with MG before or during the index pregnancy (N = 443). Unexposed women comprised 4249 women without a diagnosis of MG, matched for age, parity, hospital, and year of childbirth. The risks of adverse pregnancy, delivery, and neonatal outcomes for women with MG were estimated using regression modeling and presented as adjusted odds ratios (aOR).

Results :There was no increased risk of pregnancy complications in women with MG. Women with MG had a spontaneous onset of labor less often than women without MG (69.8% vs. 79.5%; aOR 0.59; p < 0.001) as well as higher labor induction rates and elective cesarean section deliveries (16.0% vs. 12.3%, aOR 1.42; p = 0.02 and 12.0% vs. 8.1%, aOR 1.59; p = 0.009). Infants of women with MG were born on average 2 days earlier (p = 0.002); however, these infants did not have a higher risk of having low APGAR, being small for gestational age, or having a congenital malformation.

Conclusion :This first nationwide study of pregnancy in women with MG in Sweden demonstrates reassuring results overall, suggesting generally safe pregnancy outcomes for women with MG and their infants.

There is an unmet need for objective disease-specific biomarkers in the heterogeneous autoimmune neuromuscular disorder myasthenia gravis (MG). This cross-sectional study identified a signature of 23 inflammatory serum proteins with proximity extension assay (PEA) that distinguishes acetylcholine receptor antibody seropositive (AChR+) MG patients from healthy controls (HCs). CCL28, TNFSF14, 4E-BP1, transforming growth factor alpha (TGF-α), and ST1A1 ranked top biomarkers. TGF-β1 and osteoprotegerin (OPG) differed between early- and late-onset MG, whereas CXCL10, TNFSF14, CCL11, interleukin-17C (IL-17C), and TGF-α differed significantly with immunosuppressive treatment. MG patients with moderate to high disease severity had lower uPA. Previously defined MG-associated microRNAs, miR-150-5p, miR-30e-5p, and miR-21-5p, correlated inversely with ST1A1 and TNFSF14. The presented inflammatory proteins that distinguish AChR+ MG are promising serum biomarkers for validation in prospective studies to allow for molecular signatures for patient subgroup stratification and monitoring of treatment response.

Objective. To estimate the 5-year incidence rate of autoimmune encephalitis (AE) and paraneoplastic neurological syndrome (PNS) in Sweden. Methods. All patients who were tested for a neuronal antibody in Sweden between 2015 and 2019 were included. Patients in Healthcare region Mid Sweden (population 2.1 million) were invited to participate in a case ascertainment substudy. AE and PNS cases were defined using established diagnostic criteria. Crude and age-adjusted incidence rates of AE and PNS in Healthcare region Mid Sweden were estimated. Results. The number of tests for neuronal antibodies in Sweden increased between 2015 and 2019 from 1867 to 2505 (serum) and 863 to 1376 (CSF) per annum. The frequencies of positive results were stable over the entire study period, and the mean value was 6.1% for serum (CI95% 5.5-6.7) and 4.8% for CSF (CI95% 4.0-5.6). In total, 125 patients tested positive for neuronal antibodies in Healthcare region Mid Sweden between 2015 and 2019. Of these, 94 were included, and after case ascertainment, thirty-one cases of definite AE or PNS could be identified. The 5-year incidence rate of AE and PNS was 3.0 per million person-years (95% CI 1.9-4.1). The yearly incidence rates increased in the study period, from 1.5 per million person-years in 2015 (95% CI 0.0-3.2) to 4.3 per million person-years in 2019 (95% CI 1.5-7.1). Conclusions. In this first epidemiological study of AE and PNS in Sweden, the number of cases doubled from 2015 to 2019. This likely reflects increased availability of testing and awareness of these conditions.

Although supervised aerobic and resistance training in a hospital setting was proven safe and beneficial for well-controlled myasthenia gravis (MG) patients, implementation of similar programs in the community has not been studied. We conducted a pragmatic open-label study at a large gym in Uppsala, Sweden. Seven patients with generalized MG were recruited to participate in an individualized, tailored exercise program, based on individual baseline status and personal goals, with a personal trainer. All patients completed the entire training period. The individually tailored exercise program was implemented safely and effectively, with all patients improving in aerobic capacity, muscle strength, and balance. Our pragmatic open-label case study suggests that well-controlled patients with generalized MG can extend their physical exercise to personal training in the gym. This is an essential step towards reducing the barriers to implementing exercise procols and increasing the availability of these interventions to MG patients.

Aesthetic use of low doses of Botulinum toxin (BoNT) injections into the facial muscles has become a leading non-surgical aesthetic treatment worldwide to reduce facial wrinkles, including glabellar lines, forehead lines, and periorbital wrinkles. Within these aesthetic applications, BoNT injections intend to reduce and prevent wrinkles, and the recommended usage of 2 years is often exceeded, which may result in atrophy of the injected muscles. The long-term effects of BoNT injections in the facial muscles and the evidence of diffusion of BoNT to surrounding muscles are obvious pitfalls and challenges for clinical neurophysiologists in differential diagnosing neuromuscular transmission failures. Also, this is further complicated by the risk of developing side effects upon permanent chemical denervation of facial muscles, with less possibility for reinnervation.

This review summarizes the known long-term effects of BoNT over time in different facial muscles and the use of objective electrophysiological measures to evaluate these. A better understanding of the longterm effects of BoNT is essential to avoid misdiagnosing other neuromuscular disorders.

Background and purpose Although myasthenia gravis (MG) is recognized as an immunoglobulin G autoantibody-mediated disease, the relationship between autoantibody levels and disease activity in MG is unclear. We sought to evaluate this landscape through systematically assessing the evidence, testing the impact of predefined variables on any relationship, and augmenting with expert opinion. Methods In October 2020, a forum of leading clinicians and researchers in neurology from across Europe (Expert Forum for Rare Autoantibodies in Neurology in Myasthenia Gravis) participated in a series of virtual meetings that took place alongside the conduct of a systematic literature review (SLR). Results Forty-two studies were identified meeting inclusion criteria. Of these, 10 reported some correlation between a patient's autoantibody level and disease severity. Generally, decreased autoantibody levels (acetylcholine receptor, muscle-specific kinase, and titin) were positively and significantly correlated with improvements in disease severity (Quantitative Myasthenia Gravis score, Myasthenia Gravis Composite score, Myasthenia Gravis Activities of Daily Living score, Myasthenia Gravis Foundation of America classification). Given the limited evidence, testing the impact of predefined variables was not feasible. Conclusions This first SLR to assess whether a correlation exists between autoantibody levels and disease activity in patients with MG has indicated a potential positive correlation, which could have clinical implications in guiding treatment decisions. However, in light of the limited and variable evidence, we cannot currently recommend routine clinical use of autoantibody level testing in this context. For now, patient's characteristics, clinical disease course, and laboratory data (e.g., autoantibody status, thymus histology) should inform management, alongside patient-reported outcomes. We highlight the need for future studies to reach more definitive conclusions on this relationship.

IMPORTANCE Rituximab is a third-line option for refractory generalized myasthenia gravis (MG) based on empirical evidence, but its effect in new-onset disease is unknown. OBJECTIVE To investigate the efficacy and safety of rituximab compared with placebo as an add-on to standard of care for MG. DESIGN, SETTING, AND PARTICIPANTS This randomized, double-blind, placebo-controlled study took place throughout 48 weeks at 7 regional clinics in Sweden. Key inclusion criteria were age older than 18 years, onset of generalized symptoms within 12 months or less, and a Quantitative Myasthenia Gravis (QMG) score of 6 or more. Patients were screened from October 20, 2016, to March 2, 2020. Key exclusion criteria included pure ocular MG, suspected thymoma, previous thymectomy, and prior noncorticosteroid immunosuppressants or high doses of corticosteroids. INTERVENTIONS Participants were randomized 1:1 without stratification to a single intravenous infusion of 500 mg of rituximab or matching placebo. MAIN OUTCOMES AND MEASURES Minimal disease manifestations at 16 weeks defined as a QMG score of 4 or less with prednisolone, 10 mg or less daily, and no rescue treatment. RESULTS Of 87 potentially eligible patients, 25 were randomized to rituximab (mean [SD] age, 67.4 [13.4] years; 7 [28%] female) and 22 to placebo (mean [SD] age, 58 [18.6] years; 7 [32%] female). Compared with placebo, a greater proportion with rituximab met the primary end point; 71% (17 of 24) in the rituximab group vs 29% (6 of 21) in the placebo group (Fisher exact test P = .007; probability ratio, 2.48 [95% CI, 1.20-5.11]). Secondary end points, comparing changes in Myasthenia Gravis Activities of Daily Living and Myasthenia Gravis Quality of Life at 16 weeks with QMG at 24 weeks did not differ between groups with censoring for rescue treatment (per-protocol analysis) but were in favor of active treatment when rescue treatment was taken into account by worst rank imputation (post hoc analysis). Rescue treatments were also more frequent in the placebo arm (rituximab: 1 [4%]; placebo, 8 [36%]). One patient in the placebo arm had a myocardial infarction with cardiac arrest and 1 patient in the active arm experienced a fatal cardiac event. CONCLUSIONS AND RELEVANCE A single dose of 500 mg of rituximab was associated with greater probability of minimal MG manifestations and reduced need of rescue medications compared with placebo. Further studies are needed to address long-term benefit-risk balance with this treatment.

Muscle-specific kinase (MuSK) myasthenia gravis (MG) is a neuromuscular autoimmune disease belonging to a growing group of IgG4 autoimmune diseases (IgG4-AIDs), in which the majority of pathogenic autoantibodies are of the IgG4 subclass. The more prevalent form of MG with acetylcholine receptor (AChR) antibodies is caused by IgG1-3 autoantibodies. A dominant role for IgG4 in autoimmune disease is intriguing due to its antiinflammatory characteristics. It is unclear why MuSK autoantibodies are predominantly IgG4. We hypothesized that MuSK MG patients have a general predisposition to generate IgG4 responses, therefore resulting in high levels of circulating IgG4. To investigate this, we quantified serum Ig isotypes and IgG subclasses using nephelometric and turbidimetric assays in MuSK MG and AChR MG patients not under influence of immunosuppressive treatment. Absolute serum IgG1 was increased in both MuSK and AChR MG patients compared to healthy donors. In addition, only MuSK MG patients on average had significantly increased and enriched serum IgG4. Although more MuSK MG patients had elevated serum IgG4, for most the IgG4 serum levels fell within the normal range. Correlation analyses suggest MuSK-specific antibodies do not solely explain the variation in IgG4 levels. In conclusion, although serum IgG4 levels are slightly increased, the levels do not support ubiquitous IgG4 responses in MuSK MG patients as the underlying cause of dominant IgG4 MuSK antibodies.