Pregnancy outcomes in anti-NMDA receptor encephalitis: Case series

Predicting the future of autoimmune encephalitides

The concept that many neurologic and psychiatric disorders of unknown cause are immune-mediated has evolved fast during the past 20 years. The main contribution to the expansion of this field has been the discovery of antibodies that attack neuronal or glial cell-surface proteins or receptors, directly modifying their structure and function. These antibodies facilitate the diagnosis and prompt treatment of patients who often improve with immunotherapy. The identification of this group of diseases, collectively named "autoimmune encephalitides", was preceded by many years of investigations on other autoimmune CNS disorders in which the antibodies are against intracellular proteins, occur more frequently with cancer, and associate with cytotoxic T-cell responses that are less responsive to immunotherapy. Here, we first trace the recent history of the autoimmune encephalitides and address how to assess the clinical value and implement in our practice the rapid pace of autoantibody discovery. In addition, we review recent developments in the post-acute stage of the two main autoimmune encephalitides (NMDAR and LGI1) focusing on symptoms that are frequently overlooked or missed, and therefore undertreated. Because a better understanding of the pathophysiology of these diseases relies on animal models, we examine currently available studies, recognizing the existing needs for better and all-inclusive neuro-immunobiological models. Finally, we assess the status of biomarkers of disease outcome, clinical scales, current treatment strategies, and emerging therapies including CAR T-cell technology. Altogether, this overview is intended to identify gaps of knowledge and provide suggestions for improvement and insights for future research.

Perinatal outcome in anti-NMDAr encephalitis during pregnancy-a systematic review with individual patients' data analysis

INTRODUCTION

Anti-N-methyl-D-aspartate receptor (NMDAr) antibody encephalitis is an autoimmune disorder characterized by synaptic NMDAr current disruption and receptor hypofunction, often affecting women during pregnancy. Clinical manifestations associated with anti-NMDAr encephalitis can occur both in the mother and fetus.

METHODS

We generated a systematic search of the literature to identify epidemiological, clinical, and serological data related to pregnant women with anti-NMDAr encephalitis and their children, analyzing the fetal outcomes. We examined the age and neurologic symptoms of the mothers, the presence of an underlying tumor, immunotherapies used during pregnancy, duration of the pregnancy, and type of delivery.

RESULTS

Data from 41 patients were extrapolated from the included studies. Spontaneous interruption of pregnancy, premature birth, and cesarean section were reported in pregnant women with NMDAr encephalitis. Several fetal and neonatal symptoms (e.g., movement disorders, spina bifida, poor sucking, respiratory distress, cardiac arrhythmias, infections, icterus, hypoglycemia, and low birth weight) depending on the mother's serum anti-NR1 concentration were also reported.

CONCLUSIONS

We characterized the outcomes of children born from mothers with anti-NMDAr encephalitis, analyzing the pivotal risk factors related to pregnancy and maternal disorder. Neuropsychiatric involvement seems strictly related to pathogenic NMDAr antibodies detected in maternal and/or neonatal serum. These findings clarify a complex condition to manage, outlining the risks associated with pregnant women with anti-NMDAr encephalitis and also providing a concrete guide for therapeutic strategies to prevent potential harm to the fetus and the child's neurodevelopment.

Anti-NMDAR encephalitis in a child with long impaired consciousness and persistent antibodies: a case report and mini review

We described a challenging case of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis in a young girl. Despite enduring months of reduced consciousness with ongoing antibody presence, she ultimately exhibited remarkable improvement within a 5-year follow-up period. Additionally, we conducted a concise review of relevant literature on anti-NMDAR encephalitis, with a specific focus on anti-NMDAR antibodies. Our findings enhance the clinical comprehension of anti-NMDAR encephalitis and offer valuable insights to clinicians for its management.

Autoimmune encephalitis during pregnancy: A diagnostic and therapeutic challenge-A systematic review with individual patients' analysis and clinical recommendations

Several reports have described the autoimmune encephalitis' (AE) possible onset during pregnancy. In this systematic review, we summarize the available data on the diagnostic and therapeutic approach to AE during pregnancy, highlighting the associated maternal and fetal clinical outcomes. A systematic search of the literature was performed. The following databases were used: PubMed, Google Scholar, EMBASE, and CrossRef. The revision was registered on the PROSPERO platform (CRD42022336357). Forty-nine patients were included. AE onset was mainly observed during the first and the second trimester of pregnancy with psychiatric manifestations and seizures as main onset symptoms. CSF analysis showed AE-specific autoantibody positivity in 33 patients (anti-NMDA receptor as the most frequent). EEG generally showed normal findings. MRI revealed pathological findings in less than half of patients. Tumor screening was positive in 14 cases. First-line immunotherapy (single or combined) was generally employed while second line was administered in a minority of patients. Levetiracetam was the most used antiseizure medication. Cesarean section was performed in 18 women. Most of the women had an excellent early outcome after delivery but 22 showed persistent neurological deficits in long-term follow-up. Fetal outcome was positive in 33 cases, whereas 12 cases of fetal death were reported. A logistic regression showed that no variable significantly influenced the odds of good/bad maternal and fetal clinical outcome. Diagnosis and treatment of AE during pregnancy is challenging. The rate of miscarriage in women with AE seems to be higher than the general population. In addition, mothers may show long-term neurological deficits.

The Management and Diagnosis of Anti-NMDA Receptor Autoimmune Encephalitis in Pregnant Women: A Case Report and Literature Review

Rationale: Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is a form of autoimmune synaptic encephalitis, often mediated by neuronal surface antibodies. Clinically, it manifests through a diverse range of neurological and psychiatric symptoms, primarily affecting young women with ovarian teratoma, which is rare in pregnant women. Patient concerns: We report a case of a 35-year-old multiparous pregnant patient at 38 weeks of gestation presented to the emergency room with seizure, psychiatric symptoms like delirious speech with mystical visual and auditory hallucinations, bradylalia, and retrograde amnesia. Diagnosis: The diagnosis of autoimmune encephalitis with anti-NMDA antibodies was concluded by considering the lumbar puncture results, brain imaging, and the patient's persistent symptoms. Outcomes: This case is noteworthy for its rarity and the symptoms' breadth. At 38 weeks of gestation, the patient underwent a cesarean section, resulting in excellent maternal recovery observed during the 6-month follow-up and good neonatal adaptation. Lessons: Our goals include raising awareness about this condition and emphasizing the significance of early diagnosis. This encephalitis is treatable and potentially reversible, underscoring the importance of prompt identification.

An update on malignant tumor-related stiff person syndrome spectrum disorders: clinical mechanism, treatment, and outcomes

Stiff person syndrome (SPS) is a rare central nervous system disorder associated with malignancies. In this review, we retrieved information from PubMed, up until August 2023, using various search terms and their combinations, including SPS, stiff person syndrome spectrum disorders (SPSSDs), paraneoplastic, cancer, and malignant tumor. Data from peer-reviewed journals printed in English were organized to explain the possible relationships between different carcinomas and SPSSD subtypes, as well as related autoantigens. From literature searching, it was revealed that breast cancer was the most prevalent carcinoma linked to SPSSDs, followed by lung cancer and lymphoma. Furthermore, classic SPS was the most common SPSSD subtype, followed by stiff limb syndrome and progressive encephalomyelitis with rigidity and myoclonus. GAD65 was the most common autoantigen in patients with cancer and SPSSDs, followed by amphiphysin and GlyR. Patients with cancer subtypes might have multiple SPSSD subtypes, and conversely, patients with SPSSD subtypes might have multiple carcinoma subtypes. The first aim of this review was to highlight the complex nature of the relationships among cancers, autoantigens, and SPSSDs as new information in this field continues to be generated globally. The adoption of an open-minded approach to updating information on new cancer subtypes, autoantigens, and SPSSDs is recommended to renew our database. The second aim of this review was to discuss SPS animal models, which will help us to understand the mechanisms underlying the pathogenesis of SPS. In future, elucidating the relationship among cancers, autoantigens, and SPSSDs is critical for the early prediction of cancer and discovery of new therapeutic modalities.

Epstein-Barr virus reactivation-related meningoencephalitis with transverse myelitis in pregnancy

Key Clinical Message

Consider the differential of Epstein-Barr virus (EBV) reactivation in pregnant women who develop progressive meningoencephalitis and transverse myelitis. EBV nucleic acid amplification should be considered in immunosuppressed patients.

Abstract

A 32-year-old G10P6M3K22 pregnant female presented to a regional hospital with progressive severe neurological and behavioral deficits. Magnetic resonance revealed cervical transverse myelitis. Lumbar puncture confirmed Epstein-Barr virus (EBV) DNA on a background of IgG-positive EBV serology. A diagnosis of EBV reactivation-related meningoencephalitis with transverse myelitis in pregnancy was concluded.

Concurrent NMDAR and GFAP Antibody Encephalitis During Pregnancy

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune antibody encephalitis, commonly affecting young women with comorbid ovarian teratoma. It typically presents with alteration of consciousness, psychosis, movement disorders eventually deteriorating with seizures, dysautonomia and central hypoventilation requiring critical level of care that may last weeks to months. Removal of teratoma and immunosuppressant therapy support can led to a dramatic recovery.To our knowledge, this is the first illustrated case in the literature of a pregnant woman presenting with concurrent autoimmune NMDAR and anti-glial gibrillary acidic protein(GFAP) antibody encephalitis in the setting of an ovarian teratoma. Despite the teratoma removal and receiving various forms of immunosuppressant therapy, a meaningful neurological improvement was observed following the delivery. After a prolonged hospitalisation and recovery period, the patient and her offspring made an excellent recovery highlighting the significance of early diagnosis and management.

Delta brush on EEG: a characteristic EEG finding in autoimmune encephalitis

A woman in her late 20s was admitted via the emergency department in the psychiatric ward with acute-onset behavioural changes and suicidal thoughts in the past 2 weeks. Workup revealed positive N-methyl-D-aspartate (NMDA) receptor antibodies in cerebrospinal fluid and electroencephalogram (EEG) showing a specific pattern of delta brush on bilateral frontal regions. Other investigations were unremarkable. The patient was started on intravenous methylprednisolone 1000 mg for 5 days with oral steroids. She responded on steroids. She has been recommended for workup for teratoma/mediastinal tumours with NMDA receptor encephalitis is an autoimmune disorder predominantly affecting women of childbearing age. Delta brush pattern on EEG is specific for NMDA receptor encephalitis hence can be used as a diagnostic tool. It is advisable to investigate any patient with the presentation of mental deterioration for pathological causes. However, treatment with immunotherapy increases the chance of survival and may prevent cognitive impairment.

Anti-CD20 therapies in pregnancy and breast feeding: a review and ABN guidelines

Neurologists increasingly use anti-CD20 therapies, including for women of childbearing age, despite these medications being unlicensed for use in pregnancy. Current evidence suggests that women can safely conceive while taking anti-CD20 therapy. Women should not be denied treatment during pregnancy when it is clinically indicated, although they should be counselled regarding live vaccinations for their infant. Women receiving regular ocrelizumab for multiple sclerosis should preferably wait 3 months before trying to conceive. There are few data around ofatumumab in pregnancy, and while there is probably a class effect across all anti-CD20 therapies, ofatumumab may need to be continued during pregnancy to maintain efficacy. We recommend that anti-CD20 therapies can be safely given while breast feeding. It is important to make time to discuss treatments with women of childbearing age to help them choose their most suitable treatment. Outcomes should be monitored in pregnancy registries.

Pregnancy and antibody-mediated CNS disorders: What do we know and what should we know?

Antibody-mediated central nervous system (CNS) disorders including those associated with aquaporin-4 or myelin oligodendrocyte glycoprotein IgG and autoimmune encephalitis often affect women of childbearing age. Pathogenic antibodies of these diseases can potentially alter reproductive functions and influence fetal development. Hormonal changes occurring during pregnancy may modify the course of autoimmune diseases by influencing relapse risk, attack severity, and affect the delivery and postpartum period. Moreover, balancing treatment related safety issues with the risk of potentially disabling relapses during pregnancy and breastfeeding are major challenges. Intentional prenatal, gestational, and post-partum counseling is paramount to address these issues and mitigate these risks. Fortunately, new insights on risk factors for adverse pregnancy outcomes and possible preventive strategies are emerging. This review aims to summarize the interplay between antibody-mediated CNS disorders and pregnancy during the prenatal, gestational, and postpartum periods, highlight current treatment recommendations, and discuss future areas of research.

Refractory Anti-NMDA Receptor Encephalitis in Early Pregnancy

Background and Objectives

Anti-N-methyl d-aspartate receptor (NMDAR) encephalitis classically affects women of childbearing age, producing a disproportionate number of pregnant women with anti-NMDAR encephalitis. The typical presentation includes progressive neuropsychiatric symptoms, seizures, and alterations in consciousness, all of which present potential risks to the fetus. First-line and second-line treatments similarly pose teratogenic potential; therefore, randomized studies with supportive data on pregnancy and fetal outcomes are lacking.

Methods

We present a case of refractory anti-NMDAR encephalitis during the first and second trimesters of pregnancy with the successful use of rituximab and cyclophosphamide and resultant healthy pregnancy.

Results

The patient was treated with an escalating immunotherapy regimen from 11 to 15 weeks of gestation, including steroids, plasma exchange, IV immunoglobulins, and rituximab, with no clinical response. At 16 weeks of gestation, she received cyclophosphamide with clinical improvement after 4 weeks. She subsequently gave birth to a healthy, term baby boy, who continued to do well at the follow-up.

Discussion

This case illustrates the effective use of cyclophosphamide in the second trimester of pregnancy for anti-NMDAR encephalitis. The use of second-line therapies remains an individualized decision because the relative risk-to-benefit ratio in pregnant women is incompletely understood.

Psychiatric manifestations of autoimmune encephalitis

Autoimmune encephalitis is increasingly recognized as a cause of psychiatric symptoms. A wide spectrum of psychiatric manifestations have been described which may precede, follow or occur independently of neurologic features. Patients typically respond to immunotherapy, however diagnosis is challenging due to phenotypic heterogeneity. The aim of this review is to provide an overview of the psychiatric features associated with encephalitis mediated by autoantibodies targeting neuronal cell-surface antigens and describe indicators of potential immunopathology underlying psychiatric manifestations.

NMDA Autoimmune Encephalitis and Severe Persistent Hypokalemia in a Pregnant Woman

Introduction: For more than a decade, NMDAR autoimmune encephalitis has been studied and treated as a neurological condition, and good results have been achieve through immune therapies. Apart from being well represented in the CNS, NMDA receptors are currently known of and being studied in multiple non-neuronal cells with potential clinical significance. The association of NMDAR autoimmune encephalitis with pregnancy is rare, and hypokalemia is not mentioned. Methods: We present the case of a 30-year-old woman with NMDAR autoimmune encephalitis in her 17th week of pregnancy associated with persistent hypokalemia that had no apparent cause and resisted Kalium chloride supplementation. A diagnostic work-up including clinical, laboratory, and imagistic examinations, was performed. The case was monitored between May and September 2016 at Neurology, SCJUT. Results: Severe hypokalemia with normal serum sodium levels persisted throughout the course of clinical manifestation of anti-NMDAR autoimmune encephalitis. Conclusions: NMDAR autoimmune encephalitis is under-diagnosed in its atypical clinical variants, and this disease’s association with hypokalemia is not mentioned in the literature. Still, it is of clinical importance because it attests to the implications of other organs/systems in the general autoimmune process of NMDAR encephalitis, and it might change the way we address certain psychiatric disorders by searching underlying organic conditions.

Impairment of early neuronal maturation in anti-NMDA-receptor encephalitis

RATIONALE

Adequate immunotherapies for anti-NMDAR encephalitis during pregnancy produce a relatively good clinical outcome for pregnant mothers and their infants, but there are no reports about the future growth of their babies. The damage of anti-NMDAR antibodies to early neuronal development is still unknown.

OBJECTIVES

Serum or cerebrospinal fluid from one patient with anti-NMDAR encephalitis (the index patient) and one patient with schizophrenia (the control patient) was administered to primary cultures of dissociated rat cortical neurons, and dendritic outgrowth, centrosome elimination, and branching of dendrites were investigated. For rescue experiments, serum of the index patient was replaced with normal culture media after 3 days' administration of the index patient.

RESULTS

Serum and cerebrospinal fluid of the index patient statistically significantly impaired dendritic outgrowth of cultured rat cortical primary neurons. Serum of the index patient also statistically significantly delayed centrosome elimination. Impaired dendritic outgrowth and delayed centrosome elimination were not perfectly rescued by changing to normal culture media. Serum of the index patient also statistically significantly reduced the branching of dendrites.

CONCLUSIONS

This is the first demonstration of the damage by anti-NMDAR antibodies on early dendritic development in vitro. As a strategy to protect embryonic neurons, our findings may support the efficacy of early immunotherapy for anti-NMDAR encephalitis in pregnancy.

Anti N-methyl-D-aspartate receptor (NMDAr) encephalitis during pregnancy: A case report

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Focal motor status epilepticus can be a presenting sign of anti-NMDA rencephalitis during pregnancy.

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After the immunomodulatory treatment, the patient showed only attention deficits with normal global cognition.

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The newborn presented normal birth weight kg with APGAR 10 with no sign of fetal distress nor major or minor malformations.

Anti-N-methyl-D-aspartate receptor (NMDAr) antibody encephalitis is an autoimmune disorder characterized by reduced synaptic activity of the NMDAr due to circulating antibodies that target the NR1 subunit. Few cases of anti-NMDAR encephalitis during pregnancy have been described. The permeation of anti-NR1 antibodies through the placenta can be instrumental in the development of complications in newborns. We describe a case of a young woman suffering from anti-NMDAR encephalitis during the first trimester of pregnancy and focus on diagnostic and therapeutic management.

Strategies for the Emergency Treatment of Pregnant Women with Neurological Symptoms during the COVID-19 Pandemic

Coronavirus disease-19 (COVID-19) has been spreading all over the world for more than two years. Though several kinds of vaccines are currently available, emergence of new variants, spike mutations and immune escape have raised new challenges. Pregnant women are vulnerable to respiratory infections due to their altered immune defence and surveillance functions. Besides, whether pregnant persons should receive a COVID-19 vaccine is still under debate because limited data are available on the efficacy and safety of receiving a vaccine during pregnancy. Physiological features and lack of effective protection making pregnant women at high risk of getting infected. Another concern is that pregnancy may trigger the onset of underlying existing neurological disease, which is highly similar to those neurological symptoms of pregnant women caused by COVID-19. These similarities interfere with diagnosis and delay timely and effective management. Therefore, providing efficient emergency support for pregnant women suffering from neurological symptoms caused by COVID-19 remains a challenge among neurologists and obstetricians. To improve the diagnosis and treatment efficiency of pregnant women with neurological symptoms, we propose an emergency management framework based on the clinicians' experience and available resources. This emergency care system aimed at addressing the conundrums faced by the emergency guarantee system under COVID-19 pandemic and could serve as a potential multisystem project for clinical practice and medical education.

Autoantibodies in neurological disease

The realization that autoantibodies can contribute to dysfunction of the brain has brought about a paradigm shift in neurological diseases over the past decade, offering up important novel diagnostic and therapeutic opportunities. Detection of specific autoantibodies to neuronal or glial targets has resulted in a better understanding of central nervous system autoimmunity and in the reclassification of some diseases previously thought to result from infectious, 'idiopathic' or psychogenic causes. The most prominent examples, such as aquaporin 4 autoantibodies in neuromyelitis optica or NMDAR autoantibodies in encephalitis, have stimulated an entire field of clinical and experimental studies on disease mechanisms and immunological abnormalities. Also, these findings inspired the search for additional autoantibodies, which has been very successful to date and has not yet reached its peak. This Review summarizes this rapid development at a point in time where preclinical studies have started delivering fundamental new data for mechanistic understanding, where new technologies are being introduced into this field, and - most importantly - where the first specifically tailored immunotherapeutic approaches are emerging.

Blocking Placental Class G Immunoglobulin Transfer Prevents NMDA Receptor Antibody Effects in Newborn Mice

BACKGROUND AND OBJECTIVES

To determine in a mouse model whether neonatal Fc receptor (FcRn) blockade prevents the placental transfer of class G immunoglobulin (IgG) derived from patients with anti-NMDA receptor (NMDAR) encephalitis and their pathogenic effects on the fetuses and offspring.

METHODS

Pregnant C57BL/6J mice were administered via tail vein FcRn antibody (FcRn-ab) or saline solution 6 hours before administration of patients' or controls' IgG on days 14, 15, and 16 of gestation. Three experimental groups were established: mice receiving controls' IgG, patients' IgG, or patients' IgG along with pretreatment with FcRn-ab. Immunohistochemical staining, confocal microscopy, hippocampal long-term potentiation, and standardized developmental and behavioral tasks were used to assess the efficacy of treatment with FcRn-ab.

RESULTS

In pregnant mice that received patients' IgG, treatment with FcRn-ab prevented the IgG from reaching the fetal brain, abrogating the decrease of NMDAR clusters and the reduction of cortical plate thickness that were observed in fetuses from untreated pregnant mice. Moreover, among the offspring of mothers that received patients' IgG, those whose mothers were treated with FcRn-ab did not develop the alterations that occurred in offspring of untreated mothers, including impairment in hippocampal plasticity, delay in innate reflexes, and visuospatial memory deficits.

DISCUSSION

FcRn blockade prevents placental transfer of IgG from patients with anti-NMDAR encephalitis and abrogates the synaptic and neurodevelopmental alterations caused by patients' antibodies. This model has potential therapeutic implications for other antibody-mediated diseases of the CNS during pregnancy.

A Systematic Review of the safety of non-TNF inhibitor biologic and targeted synthetic drugs in rheumatic disease in pregnancy

INTRODUCTION

Despite increasing evidence to support safe use of tumour necrosis factor inhibitors (TNFi) and other biologic disease modifying anti-rheumatic drugs (bDMARDs) during pre-conception/pregnancy, there remains a paucity of evidence regarding the safety and compatibility of other non-TNFi and novel targeted synthetic (ts)DMARDs during pre-conception/pregnancy. Therefore, we conducted a systematic review to determine the compatibility of these drugs in pre-conception, during pregnancy and post-partum period.

METHOD

Databases including; EMBASE, Pubmed (MEDLINE), and Cochrane were searched up to 23rd October 2020 to find relevant peer-reviewed papers, using keywords including; rheumatic disease, pregnancy, conception/pre-conception, lactation/breastfeeding, childhood and vaccination/infection, and commonly prescribed non-TNFi drugs and tsDMARDs.

RESULTS

Our search yielded 1483 papers that were screened independently by two authors, and 109 full-text papers were eligible for final analysis. These studies reported 1291 maternal pregnancies exposed to non-TNFi bDMARDs and tsDMARDs with known outcomes, including 721 live births, 219 spontaneous miscarriages and 27 congenital abnormalities. Paternal exposures in 174 pregnancies had reassuring outcomes. A total of 48 breast-fed infants were exposed to non-TNFi bDMARDs and no adverse events reported upon long-term follow-up. Fifteen infants exposed to bDMARDs received normal vaccination regimes, including live vaccines, and had normal developmental outcomes, without any complications or infections.

CONCLUSION

Overall, the findings are reassuring and do not suggest a cause for any major concerns or an increased risk of adverse pregnancy outcomes for maternal or paternal exposures to non-TNFi bDMARDs or tsDMARDs. There were no major concerns for breastfeeding exposures to non-TNFi bDMARDs.

Recurrent anti-NMDAR encephalitis during pregnancy combined with two antibodies positive

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune synaptic encephalitis likely mediated by neuronal surface antibody. Clinically, it is characterized by a variety of neurological and psychiatric symptoms, predominantly affecting young women. Recurrent anti-NMDAR cases combined with double-antibody positive during pregnancy have not been reported. We report a 19-year-old pregnant woman with recurrent anti-NMDAR encephalitis and double-antibody positive. Through our case report and a review of the literature, we hope to heighten an awareness of anti-NMDAR encephalitis, particularly in a pregnant setting.

Placental transfer of NMDAR antibodies causes reversible alterations in mice

Objective

To determine whether maternofetal transfer of NMDA receptor (NMDAR) antibodies has pathogenic effects on the fetus and offspring, we developed a model of placental transfer of antibodies.

Methods

Pregnant C57BL/6J mice were administered via tail vein patients' or controls' immunoglobulin G (IgG) on days 14–16 of gestation, when the placenta is able to transport IgG and the immature fetal blood-brain barrier is less restrictive to IgG crossing. Immunohistochemical and DiOlistic (gene gun delivery of fluorescent dye) staining, confocal microscopy, standardized developmental and behavioral tasks, and hippocampal long-term potentiation were used to determine the antibody effects.

Results

In brains of fetuses, patients' IgG, but not controls' IgG, bound to NMDAR, causing a decrease in NMDAR clusters and cortical plate thickness. No increase in neonatal mortality was observed, but offspring exposed in utero to patients' IgG had reduced levels of cell-surface and synaptic NMDAR, increased dendritic arborization, decreased density of mature (mushroom-shaped) spines, microglial activation, and thinning of brain cortical layers II–IV with cellular compaction. These animals also had a delay in innate reflexes and eye opening and during follow-up showed depressive-like behavior, deficits in nest building, poor motor coordination, and impaired social-spatial memory and hippocampal plasticity. Remarkably, all these paradigms progressively improved (becoming similar to those of controls) during follow-up until adulthood.

Conclusions

In this model, placental transfer of patients' NMDAR antibodies caused severe but reversible synaptic and neurodevelopmental alterations. Reversible antibody effects may contribute to the infrequent and limited number of complications described in children of patients who develop anti-NMDAR encephalitis during pregnancy.

Gender issues of antibody-mediated diseases in neurology: (NMOSD/autoimmune encephalitis/MG)

Neuromyelitis optica spectrum disorder (NMOSD), autoimmune encephalitis (AE), myasthenia gravis (MG) and Lambert-Eaton myasthenic syndrome (LEMS) are antibody-mediated neurological diseases. They have mostly female predominance, affecting many women during childbearing age. Interactions between the underlying disease (or necessary treatment) and pregnancy can occur in every of these illnesses. Herein, we present the characteristics of NMOSD, AE, MG and LEMS in general, and review published data regarding the influence of the different diseases on fertility, pregnancy, puerperium, treatment strategy during pregnancy and post-partum period, and menopause but also male factors. We summarise key elements that should be borne in mind when confronted with such cases.

Maternal-Autoantibody-Related (MAR) Autism: Identifying Neuronal Antigens and Approaching Prospects for Intervention

Recent studies indicate the existence of a maternal-autoantibody-related subtype of autism spectrum disorder (ASD). To date, a large number of studies have focused on describing patterns of brain-reactive serum antibodies in maternal-autoantibody-related (MAR) autism and some have described attempts to define the antigenic targets. This article describes evidence on MAR autism and the various autoantibodies that have been implicated. Among other possibilities, antibodies to neuronal surface protein Contactin Associated Protein 2 (CASPR2) have been found more frequently in mothers of children with neurodevelopmental disorders or autism, and two independent experimental studies have shown pathogenicity in mice. The N-methyl-D-aspartate receptor (NMDAR) is another possible target for maternal antibodies as demonstrated in mice. Here, we discuss the growing evidence, discuss issues regarding biomarker definition, and summarise the therapeutic approaches that might be used to reduce or prevent the transfer of pathogenic maternal antibodies.