Anti-N-methyl-D-aspartate receptor encephalitis with an imaging-invisible ovarian teratoma: a case report

Coexisting Sacrococcygeal Teratoma With Mild Encephalitis/Encephalopathy With a Reversible Splenial Lesion: A Case Report

Mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is a rare disease characterized by a reversible lesion in the splenium of the corpus callosum (SCC) observed on MRI. The exact etiology of MERS is unknown, although infections and antiepileptic drugs have been reported as potential causes. Herein, we present the case of a 56-year-old male patient who experienced fever and headache for 3 days. He was referred to our hospital after symptomatic treatment by his primary care physician failed to improve his symptoms. The patient had no psychiatric symptoms or significant neurological findings. Head MRI revealed a high signal on SCC on diffusion-weighted imaging, raising the suspicion of MERS. All examinations to determine the cause of MERS were negative. The patient's symptoms improved with antibiotics and B complex vitamins. Upon admission, abdominal CT incidentally revealed a well-defined mass on the dorsal surface of the rectum suspected to be a tailgut cyst, warranting surgical resection. The cranial margin of the tumor was caudal to the third sacrum, and a trans-sacral approach was used for resection. The fifth sacrum and the coccyx were resected, and the tumor was resected without damaging the rectum. A histopathological examination revealed a mature teratoma without any malignancy. A follow-up CT at four months postoperatively showed no evidence of clinical recurrence of MERS. Adult-onset MERS is relatively rare, and no association with tumors has been reported. The association between encephalitis and teratomas includes ovarian teratomas, which cause anti-N-methyl-D-aspartate receptor encephalitis and paraneoplastic limbic encephalitis. Although the cause of MERS was unknown in this case, we report the coexistence of a sacral teratoma and MERS to contribute to the knowledge of the association between them.

Ovarian resection in anti-N-methyl-D-aspartate receptor encephalitis: A comparison of surgical approaches

Background

For patients with anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) and ovarian teratoma, “conservative” surgical approaches (complete or partial unilateral oophorectomy or bilateral partial oophorectomies) are associated with clinical improvement. “Aggressive” ovarian resections (complete bilateral oophorectomy or “blind” ovarian resections without pre-operative evidence of teratoma) are also reported, although the evidence supporting these approaches is unclear.

Objective

To compare the one-year functional outcomes of patients with NMDARE who underwent conservative vs. aggressive ovarian resections.

Methods

Patients with NMDARE undergoing ovarian resection between January 1st, 2012 and December 31st, 2021 were retrospectively identified from three North American tertiary care centers. Primary outcome was a modified Rankin Scale score of 0–2 one year after ovarian resection. Fisher exact and Wilcoxon rank sum tests were used to compare demographic features, disease characteristics, and functional outcomes between the two surgical groups. A fixed-effects meta-analysis of studies reporting functional outcomes based on surgical approach was also performed.

Results

Twenty-three patients were included. Eight underwent aggressive surgical management. There was a non-significant trend toward an association between aggressive surgical management and younger age-at-onset, higher baseline disease severity, and longer delays to treatment. There was no difference between “aggressive” (3/8, 38%) and “conservative” (11/15, 73%) management groups in achieving the primary outcome (OR95% = <0.1–1.9; p = 0.18). Findings were similar when considering data from 52 patients in two published studies (RR = 0.74; CI95% = 0.48–1.13; p = 0.16).

Conclusions

Aggressive ovarian resection was not associated with improved outcomes in patients with NMDARE in this series. Group differences may have contributed, recognizing that patients who underwent aggressive resection tended to be sicker, with procedures performed later in the disease course. Based on available evidence, we advocate for function-sparing resection in patients with imaging-confirmed/suspected teratoma, and repeated multi-modal imaging in at-risk patients with NMDARE refractory to conventional treatment.

Mature Cystic Teratoma Combined With Autoimmune Limbic Encephalitis Mimicking Functional Ovarian Cyst

Autoimmune limbic encephalitis (ALE) associated with an anti-N-methyl-D-aspartate receptor (NMDAR) is a rare but occasionally fatal condition that could be accompanied by ovarian teratoma. We report a case of a 27-year-old woman with ALE combined with a mature cystic teratoma that looks like a functional cyst in imaging studies. A single port access laparoscopic left oophorectomy was performed. On the 154th postoperative day, symptoms were fully recovered. Teratoma detection and tumor removal are critical for the management of patients diagnosed with or suspected of ALE.

Cervical lymph nodes and ovarian teratomas as germinal centres in NMDA receptor-antibody encephalitis

Autoantibodies against the extracellular domain of the N-methyl-d-aspartate receptor (NMDAR) NR1 subunit cause a severe and common form of encephalitis. To better understand their generation, we aimed to characterize and identify human germinal centres actively participating in NMDAR-specific autoimmunization by sampling patient blood, CSF, ovarian teratoma tissue and, directly from the putative site of human CNS lymphatic drainage, cervical lymph nodes. From serum, both NR1-IgA and NR1-IgM were detected more frequently in NMDAR-antibody encephalitis patients versus controls (both P < 0.0001). Within patients, ovarian teratoma status was associated with a higher frequency of NR1-IgA positivity in serum (OR = 3.1; P < 0.0001) and CSF (OR = 3.8, P = 0.047), particularly early in disease and before ovarian teratoma resection. Consistent with this immunoglobulin class bias, ovarian teratoma samples showed intratumoral production of both NR1-IgG and NR1-IgA and, by single cell RNA sequencing, contained expanded highly-mutated IgA clones with an ovarian teratoma-restricted B cell population. Multiplex histology suggested tertiary lymphoid architectures in ovarian teratomas with dense B cell foci expressing the germinal centre marker BCL6, CD21+ follicular dendritic cells, and the NR1 subunit, alongside lymphatic vessels and high endothelial vasculature. Cultured teratoma explants and dissociated intratumoral B cells secreted NR1-IgGs in culture. Hence, ovarian teratomas showed structural and functional evidence of NR1-specific germinal centres. On exploring classical secondary lymphoid organs, B cells cultured from cervical lymph nodes of patients with NMDAR-antibody encephalitis produced NR1-IgG in 3/7 cultures, from patients with the highest serum NR1-IgG levels (P < 0.05). By contrast, NR1-IgG secretion was observed neither from cervical lymph nodes in disease controls nor in patients with adequately resected ovarian teratomas. Our multimodal evaluations provide convergent anatomical and functional evidence of NMDAR-autoantibody production from active germinal centres within both intratumoral tertiary lymphoid structures and traditional secondary lymphoid organs, the cervical lymph nodes. Furthermore, we develop a cervical lymph node sampling protocol that can be used to directly explore immune activity in health and disease at this emerging neuroimmune interface.

Mature ovarian teratoma-associated encephalitis

Introduction. Autoimmune encephalitis associated with ovarian teratoma is a serious and potentially fatal pathology. While this clinical entity is known to neurologists, the available literature rarely mentions the role of a gynecologist in diagnostic imagining and treatment. Although several months have passed from the appearance of the symptoms to surgical treatment, this case shows that even then a complete recovery is possible. Case presentation. The patient was a 28-year-old female, brought to the hospital because a sudden onset of unusual behavior - an acute psychosis with suicidal thoughts and auditory hallucinations. Soon after the admission she became delirious, uncooperative and agitated. Blood check, neurological assessment and cranial computed tomography yielded normal results. Therefore, a psychiatric disorder was suspected. Electroencephalogram revealed a diffuse encephalitic insufficiency. As cerebrospinal fluid was negative for infections, the autoimmune etiology of the disease was suspected. Abdominal computer tomography showed a complex right ovarian mass measuring 50 x 40 x 30 mm, confirmed by vaginal ultrasound. Laparoscopy with right adnexectomy was performed. The pathohistological finding showed a mature teratoma. In the meantime, the result of the cerebrospinal fluid test came positive for anti NMDAR antibodies. Six months after surgery, the patient was in a good mental and neurological status without symptoms. Conclusion. Gynecologists should be aware of the presence of ovarian tumors in encephalitis cases. A timely diagnosis of the underlying gynecological cause of a neurological condition, allows for prompt treatment and can remarkably improve clinical conditions and, thus, be lifesaving.

Anti-NMDA receptor encephalitis in an adolescent with a cryptic ovarian teratoma

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune disease frequently associated with ovarian teratomas. In cases where an ovarian teratoma is identified, treatment involves prompt removal of the ovarian teratoma, resulting in significant clinical improvement and decreased incidence of relapse. We present the case of a 14-year-old female patient admitted for progressively worsening psychiatric and neurological status, diagnosed with anti-NMDAR encephalitis, and negative initial imaging for ovarian pathology. She was in the hospital for 8 months requiring admission to the intensive care unit and multiple courses of immunotherapy before clinical improvement. Three months after discharge, she was readmitted with clinical relapse and repeat imaging showed an ovarian teratoma. Removal of the teratoma resulted in sustained clinical improvement with return to baseline and no further relapse. Our case report highlights the importance of maintaining a high suspicion for an underlying ovarian teratoma in a female patient with anti-NMDAR encephalitis, even when initial imaging is negative. Currently, there are limited data on recommendations for repeat imaging. Therefore, we recommend repeat imaging in patients resistant to multiple lines of treatment or presenting with clinical relapse.

A refractory anti-NMDA receptor encephalitis successfully treated by bilateral salpingo-oophorectomy and intrathecal injection of methotrexate and dexamethasone: a case report

Introduction

Anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is an autoimmune-mediated disease that is common in young female patients with ovarian teratomas. With appropriate immunotherapy, most patients achieve a good prognosis. Nevertheless, some patients may be refractory to first- and second-line immunotherapy, thus alternative treatments are required for these patients.

Case presentation: We present a case of anti-NMDA receptor encephalitis with ovarian teratoma. After the prompt removal of the teratoma and intense immunotherapy was administered, including an intravenous methylprednisolone pulse, intravenous immunoglobin, plasmapheresis, immunoadsorption, intravenous cyclophosphamide, and rituximab, the patient’s neurologic status did not improve. Bilateral salpingo-oophorectomy was then conducted, and intrathecal injection of methotrexate (MTX) and dexamethasone (DXM) was performed. The patient’s neurological symptoms improved dramatically, and she achieved a good prognosis after 23 months.

Conclusions

Intrathecal injection of MTX and DXM may be beneficial for treatment of refractory cases of anti-NMDA receptor encephalitis. Additional research is required to elucidate the mechanisms of intrathecal treatment with this therapy.

Anti-N-methyl-d-aspartate receptor encephalitis: A primer for acute care healthcare professionals

This primer summarizes the diagnosis, treatment, complications, and prognosis of anti-N-methyl-d-aspartate receptor encephalitis for healthcare professionals, especially those in acute care specialities. Anti-N-methyl-d-aspartate receptor encephalitis is an immune-mediated encephalitis that is classically paraneoplastic and associated with ovarian teratomas in young women. Other less common neoplastic triggers include testicular cancers, Hodgkin lymphoma, lung and breast cancers. It may also be triggered by infection, occurring as a para-infectious phenomenon, seen most commonly after herpes simplex-1 encephalitis. Presentation varies but typically consists of behavioural and cognitive manifestations, seizures, dysautonomia, movement disorders, central hypoventilation, and coma, necessitating intensive care unit admission. Diagnosis of anti-N-methyl-d-aspartate receptor encephalitis requires high clinical suspicion plus ancillary testing, the most sensitive being cerebrospinal fluid analysis for anti-N-methyl-d-aspartate receptor antibodies. Imaging in search of an ovarian teratoma should be exhaustive and tumours need to be surgically treated. Treatment should be expeditious with pulsed steroids and either plasma exchange or intravenous immunoglobulin. Second-line treatments include intravenous rituximab, cyclophosphamide, azathioprine, and intrathecal methotrexate. Most patients recover to be functionally independent, but the in-hospital course can be months long followed by extensive rehabilitation. Given the lengthy course of illness, we explain why education and debriefing are important for staff, and where families can obtain additional help.

CT and MRI characteristics of ovarian mature teratoma in patients with anti-N-methyl-D-aspartate receptor encephalitis

PURPOSE

The purpose of this study was to determine the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of ovarian mature teratoma in patients with anti-N-methyl-d-aspartate receptor encephalitis (NMDAR-E).

MATERIALS AND METHODS

A total of 125 women (mean age, 40.9±17.8 [SD] years; age range: 12-85 years) with 146 histopathologically or radiologically proven ovarian mature teratomas who underwent preoperative CT and MRI examinations were retrospectively included. Eight patients with 11 teratomas had NMDAR-E, whereas 117 patients with 135 teratomas did not have NMDAR-E. CT and MRI examinations were retrospectively reviewed and teratomas in patients with NMDAR-E were compared to those in patients without NMDAR-E. Comparisons were performed using Mann-Whitney U test or Fisher exact test.

RESULTS

In patients with NMDAR-E, maximum diameter of teratomas (26.1±9.3 [SD] mm), prevalence of teeth/calcification (36%) and rate of occupation by fat components (26%) were lower than those in patients without NMDAR-E (67.0±37.6 [SD] mm [P<0.01]; 75% [P<0.05]; and 65%[P<0.01], respectively). More than 75% of space was occupied by fat components in 76/135 teratomas (56%) in patients without NMDAR-E, whereas this was not observed in any teratoma in patients without NMDAR-E.

CONCLUSION

By comparison with teratomas in patients without NMDAR-E, teratomas in patients with NMDAR-E are smaller, have few teeth/calcification, and the amount of space occupied by fat components is smaller.

Case Report: Daratumumab in a Patient With Severe Refractory Anti-NMDA Receptor Encephalitis

Anti-NMDA receptor encephalitis is the most common type of antibody mediated autoimmune encephalitis (AIE). Patients often develop neuropsychiatric symptoms and seizures, women are affected about four times more than men, and in about 50% the disease is associated with a neoplasia, especially teratomas of the ovary. We describe the case of a 20-year-old woman suffering from a severe therapy refractory course of anti-NMDA receptor encephalitis. Treatment included glucocorticoids, plasma exchange, intravenous immunoglobulins, rituximab, and bortezomib without clinical improvement. Due to a therapy refractive course 28 weeks after disease onset, the patient received 10 cycles of daratumumab. Therapy escalation was performed with the anti-CD38 monoclonal antibody daratumumab as off label treatment, based on the therapy of refractory myeloma and led to an improvement of her clinical status. She spent about 200 days on the intensive care unit, followed by several weeks on the intermediate care unit with close follow ups every 4–6 weeks afterward. During follow-up, the patient was able to resume everyday and self-care activities, reflected by the modified Rankin scale (mRS) and Barthel index. Because this disease is potentially life threatening and can lead to irreversible brain atrophy, development of further therapy strategies are of great importance. Our case describes a successful treatment for therapy refractory anti-NMDA receptor encephalitis using the anti-CD38 antibody daratumumab.

Oophorectomy in NMDA receptor encephalitis and negative pelvic imaging

Ovarian teratomas are found in one-third of females presenting with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. When a teratoma is detected on imaging, its removal is first-line therapy. Even with multiple imaging modalities, occasionally, the teratoma is found only on subsequent imaging, long after initial presentation. Very rarely, patients have undergone oophorectomy despite negative imaging, with pathology demonstrating teratoma, and resulting clinical improvement. We present a patient in whom removal of a teratoma, not visible on conventional imaging, resulted in marked clinical improvement. Such cases present a major clinical challenge, needing to consider the risks of oophorectomy, including sterilisation and early menopause, versus the possibility of death in the absence of response to first-line (eg, corticosteroids, plasma exchange, intravenous immunoglobulin), second-line (eg, rituximab) and third-line (eg, bortezomib) immunosuppression. This decision is made more difficult as patients are usually females of childbearing age who at the time lack capacity to make medical decisions. This case also highlights the lack of consensus and guidelines for imaging modalities used to detect teratoma and when to pursue oophorectomy.

Anti-NMDA receptor encephalitis associated with ovarian tumor: the gynecologist point of view

BACKGROUND

Anti-NMDA receptor antibody (anti-NMDAr) encephalitis, although still a rare condition, is well known to neurologists as it is the leading cause of non-infectious acute encephalitis in young women. However, this is less well known to gynecologists, who may have a decisive role in etiological management. Indeed, in 30-60% of cases in women of childbearing age, it is associated with the presence of an ovarian teratoma, whose removal is crucial in the resolution of symptomatology.

OBJECTIVES

Primary objective of our work was to present a review in a very schematic and practical way for gynecologists, about the data on anti-NMDAr encephalitis in terms of epidemiology, clinical symptomatology, treatment and prognosis. The second objective was to propose a decision tree for gynecologists to guide them, in collaboration with neurologists and anesthesiologists, after the diagnosis of NMDAr encephalitis associated with an ovarian mass.

METHOD

We conducted an exhaustive review of existing data using PubMed and The Cochrane Library. Then, we illustrated this topic by presenting two typical cases from our experience.

RESULTS

Anti-NMDA antibody encephalitis association with an ovarian teratoma is common, especially in women of reproductive age. Complementary examinations in search of an ovarian teratoma must therefore be systematic to envisage a possible surgical excision that may improve patient prognosis.

CONCLUSION

Anti-NMDA antibody encephalitis should not be ignored by gynecologists whose role in management is central.

Anti-N-methyl-D-aspartate receptor encephalitis with accompanying ovarian teratoma in female patients from East China: Clinical features, treatment, and prognostic outcomes

PURPOSE

The association between anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDAR encephalitis) and teratoma is formally recognized. This study compared the clinical features, treatments and outcomes between female patients with or without accompanying teratomas and determined the potential influences of coexisting teratomas.

METHOD

Fifty-six female patients diagnosed with anti-NMDAR encephalitis were enrolled in two major tertiary hospitals in East China from January 2013 through March 2018 and were grouped as patients with or without teratoma. The clinical features were reviewed, and follow-up studies were performed. Comparisons were made between the two groups.

RESULTS

Patients with teratoma reported fewer viral prodromes (p = 0.0085) and stronger positive intensity of anti-NMDAR antibodies in cerebrospinal fluid (CSF) (p = 0.0368), while nontumor patients tended to demonstrate lymphocytic pleocytosis in CSF (p = 0.0306). Seizure types varied between individuals, with complex partial seizures more common in teratoma patients (p = 0.0105). Nontumor patients frequently required combinations of first-line and second-line immunotherapy (p = 0.0014), which may be attributed to higher mRS scores at admission (p = 0.0300). Also, they had higher mean mRS scores since the 12-month follow-up and greater probability of relapse than did patients with teratomas (p = 0.0286).

CONCLUSIONS

Symptomatology and auxiliary findings indicate that ovarian teratoma may be the immunologic trigger for anti-NMDAR encephalitis patients, while viral infection is likely to play a major part in pathogenesis for those without any detectable tumor. Overall, anti-NMDAR encephalitis patients with teratomas present with milder neurological symptoms and have better long-term outcomes after tumor removal.

Teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis: A case report and literature review

RATIONALE

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disease associated with the NMDA receptor and has a good response to treatment. However, only few cases related to teratoma have been reported. Here, we report a case of teratoma-associated anti-NMDAR encephalitis.

PATIENT CONCERNS

A 25-year-old woman presenting with fever for 20 days and psychiatric symptoms for 9 days was admitted to the hospital. The patient progressed to a minimally conscious state consistent with encephalitis.

DIAGNOSIS

Considering the possibility of autoantibody-mediated encephalitis, laboratory tests were conducted to detect anti-NMDAR antibodies in cerebrospinal fluid and serum. Results confirmed the diagnosis of anti-NMDAR encephalitis. Furthermore, gynecological ultrasound investigation detected teratoma in the left ovary.

INTERVENTIONS

After resection of the teratoma with laparoscopic adnexectom, the patient was treatment with immunosuppressive therapy.

OUTCOMES

The patient recovered gradually and was discharged 2 months after the operation.

LESSONS

Anti-NMDAR encephalitis remains difficult to diagnose because of its vague manifestations, and no clinical practice guidelines for prevention and treatment of the disease have been established yet. The clinical data of a case of teratoma-related anti-NMDAR encephalitis were analyzed, and relevant studies were reviewed.