A Case of Anti-Ma2 Encephalitis Presenting with Pendular Torsional Nystagmus.

Antibodies against the neuronal protein Ma2 have been reported in a peculiar form of paraneoplastic encephalitis with prominent involvement of the limbic, brainstem, and diencephalic structures and usually associated with germ cell testicular, lung, or breast cancer. The diagnosis is frequently challenged by atypical clinical manifestations including parkinsonism, sleep disturbances, hypothalamic-pituitary dysfunctions, and motor neuron-like syndrome. In recent years, the advent of monoclonal antibodies targeting immune checkpoints has deeply changed the treatment of different tumors, especially melanoma and lung cancer. However, given their nature, an increasing number of neurological immune-related adverse events, including ocular motor abnormalities, have been described. Here, we report a woman with advanced non-small cell lung cancer treated with anti-PD-L1 durvalumab, presenting with an isolated pendular torsional nystagmus, in association with anti-Ma2 antibodies. This peculiar case widens our knowledge on the clinical presentation of anti-Ma2 encephalitis associated with checkpoint inhibitors.

Anti-Ma-associated paraneoplastic cerebellar degeneration in a patient with nodular lymphocyte-predominant Hodgkin lymphoma: a case report.

BACKGROUND: Paraneoplastic cerebellar degeneration (PCD) is a devastating paraneoplastic syndrome that occasionally occurs in patients with Hodgkin lymphoma (HL). Anti-Ma2 is a well-characterized onconeuronal antibody and one of the causes of PCD. There has been only one previous report of anti-Ma2-associated paraneoplastic syndrome as a complication of HL. Here we present a rare case of anti-Ma2-associated PCD in a patient with nodular lymphocyte-predominant HL (NLPHL). CASE PRESENTATION: A 77-year-old man with a 3-month history of gait instability and a 2-month history of oscillopsia was referred to our hospital for further investigation. On examination, his cognition was normal. He had nystagmus in all directions of gaze; specifically, he had horizontal and rotatory nystagmus in the primary position, downbeat nystagmus after right, left, and up gaze, and upbeat nystagmus after down gaze. Although his limb ataxia was mild, his trunk ataxia was so pronounced that he was unable to walk without support. We strongly suspected paraneoplastic syndrome and tested for neuronal autoantibodies. The anti-Ma2 antibody was strongly positive in the blood and cerebrospinal fluid but other antineuronal autoantibodies were negative. Computed tomography showed an enlarged lymph node in the right axilla but no masses. Biopsy confirmed a diagnosis of NLPHL. The NLPHL cells stained with anti-Ma-2 antibody in the cytoplasm, suggesting these abnormal cells contained protein that was cross-reactive with Ma-2. CONCLUSIONS: To the best of our knowledge, this is the first case of anti-Ma2-associated PCD in a patient with NLPHL that was confirmed using immunostaining of the lymph node tissue with anti-Ma2 antibody. Our case confirms an association between anti-Ma2-associated PCD and NLPHL.

Updates in the Diagnosis and Treatment of Paraneoplastic Neurologic Syndromes.

The disorders of the central nervous system associated with cancer by remote immune-mediated mechanisms are a heterogeneous group. These disorders encompass the classic paraneoplastic disorders and the recently recognized autoimmune encephalitis associated with antibodies against neuronal cell surface or synaptic proteins that occur with or without cancer association. In the last decade, the new surge of interest in neuronal diseases associated with anti-neuronal antibodies led to the rapid discovery of new forms of disease that have different manifestations and were not previously suspected to be immune mediated. The recognition of these syndromes is important because it may lead to early detection of an underlying malignancy and prompt initiation of treatment, improving chances for a better outcome.

Anti-Ma2 encephalitis in a phenotypic female with XY gonadal dysgenesis: A case report.

Anti-Ma2 encephalitis is an autoimmune disorder that typically involves the brainstem, limbic system, and diencephalon. It can be paraneoplastic and is more common in males. We describe an unusual presentation of anti-Ma2 encephalitis in a patient with an XY chromosome and a female phenotype. She experienced various neurological symptoms, including olfactory hallucinations, episodic nausea, per-ictal water drinking, and hypersomnolence, that were poorly controlled by antiseizure medications (ASMs) and immunotherapy. Brain MRI showed abnormalities in right medial temporal and frontal regions, and blood tests detected anti-Ma2 antibodies. Screening for malignancies yielded no tumors. Pelvic CT showed bilateral inguinal masses and the absence of a uterus, while genetic studies revealed an XY karyotype. Surgical removal of the masses, shown to be primitive gonads, offered temporary relief, necessitating ongoing ASMs and immunotherapy.

Anti-Ma2 Encephalitis: An Atypical Case Associated With Klüver-Bucy Syndrome and Hypothalamic Dysfunction.

Anti-Ma2 encephalitis is a rare form of autoimmune encephalitis that has classically been described as a paraneoplastic neurobehavioral disorder due to its association with underlying malignancies. We discuss the case of a 30-year-old female with an exceptionally aggressive presentation of anti-Ma2 encephalitis accompanied by Klüver-Bucy syndrome and hypothalamic dysfunction. Her course was complicated by repeated aspiration events secondary to severe hyperphagia and delays in immunosuppressive treatment due to concerns of infection. The patient's encephalitis was refractory to multiple immunosuppressive therapies and she ultimately expired before a primary malignancy could be detected and treated.

[Anti-Ma2 paraneoplastic autoimmune encephalitis]. / Anti-Ma2 paraneoplasticheskii autoimmunnyi entsefalit.

Paraneoplastic syndromes are a heterogeneous group of conditions affecting cancer patients, where the symptoms are not owing to the local effects of the tumor but instead owing to humoral or immunologic effects. Paraneoplastic neurological syndromes (PNS) develop in less than 1% of cancer patients and can affect any part of the nervous system. A variety of PNS phenotypes are associated with anti-Ma2 antibody, primarily encephalitis with a predominant involvement of brainstem, limbic and diencephalic structures. We describe a case of anti-Ma2 autoimmune encephalitis with a recurrent course in a patient with two different primary tumors in the anamnesis.

Acute anti-Ma2 paraneoplastic encephalitis associated to pembrolizumab: a case report and review of literature.

Anti-Ma2 encephalitis is a rare neurological disorder with a predominant involvement of brainstem, limbic and diencephalic structures. Although an unspecific encephalopathy is the usual form of presentation, acute-onset neurologic symptoms and other atypical manifestations have been described and account for the challenging diagnosis of this entity. Despite being usually detected as a paraneoplastic syndrome in patients with early-stage tumors or without a previous history of malignancy, a growing concern has arisen from several cases reported in metastatic patients under treatment with immune checkpoint inhibitors. We report what to our knowledge is the first known case of anti-Ma2 encephalitis associated to pembrolizumab and presenting as an acute-onset focal neurological syndrome, consisting on acute global aphasia, right upper limb paresia, hypoacusia, sleep disorder, decreased conscious level and a motor focal status that was refractory to anticonvulsant therapy. A brain MRI scan showed a focal alteration of the cortical-subcortical signal on the left parietal lobe. CSF study found a significant hyperproteinorrhachia and electroencephalography showed lateralized periodic discharges (LPDs), suggestive of a diffuse encephalopathy. A positive result for anti-Ma2 antibodies was obtained both in blood and CSF samples through indirect immune-fluorescence (IFI) and later confirmed by western-blot technique. Our patient obtained a mild response to steroid therapy and a significant improvement after the administration of intravenous immunoglobulins. The hypothesis that checkpoint inhibitors may trigger the expression of previously subclinical paraneoplastic events, through the strengthening of cytotoxic T cells-mediated immune response, is supported by our finding of preexisting anti-Ma2 antibodies in preserved blood samples obtained before the initiation of pembrolizumab in our patient. Further research is needed to reveal if the detection of onconeural antibodies prior to a treatment with checkpoint inhibitors may be used as a predictive biomarker of neurologic immune-related high-grade toxicity.

Low-dose interleukin-2 as a novel therapeutic option for refractory paraneoplastic neurologic syndrome: a case of chronic relapsing anti-Ma2/Ta paraneoplastic myeloradiculopathy.

Paraneoplastic neurologic syndromes (PNS) caused by anti-Ma2/Ta antibodies have diverse presentations. Myeloradiculopathy is one anti-Ma2/Ta-associated PNS manifestation. We report the case of a patient with chronic relapsing anti-Ma2/Ta paraneoplastic myeloradiculopathy. The patient was successfully treated with low-dose human recombinant interleukin-2, despite having chronic relapsing symptoms and a refractory response to conventional immunotherapy.

Anti-Ma2-Associated Limbic Encephalitis after Termination of Immune Checkpoint Inhibitor Therapy for Malignant Pleural Mesothelioma.

Neurological adverse events of immune checkpoint inhibitor (ICI) therapy mostly develop within 3 months after initiation of ICI treatment. An 82-year-old male with malignant pleural mesothelioma developed anti-Ma2-associated limbic encephalitis at a delay of 18 months after the start of nivolumab therapy (3 months after termination of a 15-month course of ICI treatment). Immunotherapy with steroids and immunoglobulins resulted in moderate neurological improvement. Over the next year, malignant pleural mesothelioma gradually worsened, while the anti-Ma2 antibody test remained positive. Anti-Ma2 paraneoplastic encephalitis may occur after a delay following the discontinuation of ICI therapy.

Anti-Ma2 Antibody-Associated Paraneoplastic Neurological Syndromes: A Pilot Study.

Paraneoplastic neurologic syndromes (PNSs) are a heterogeneous group of disorders caused by the remote effects of cancer with immune-mediated pathogenesis. Anti-Ma2 antibody was defined as one of the well-characterized onconeural antibodies that could help establish a definite PNS diagnosis. We aimed to report and explore patients with anti-Ma2 antibody-associated paraneoplastic neurologic syndrome (Ma2-PNS) who frequently exhibit sensorimotor neuropathy (SMN) using a new method of factor analysis of mixed data (FAMD). Clinical data from a case series of eight patients with definite diagnoses were retrospectively reviewed. FAMD conducted further analyses with a comprehensive visualization in R software. Our cohort, with a predominance of females (5/8), presented more frequently with SMN (4/8), followed by limbic encephalitis (LE) (3/8). Two patients with LE were found to have a testicular germ-cell tumor and a thymoma, respectively. In addition, a patient who developed chronic SMN was diagnosed with multiple myeloma (MM) involving multiple organs. FAMD exhibited the overall features into a two-dimensional coordinate and located each individual into their corresponding position with high relevance. It provided a clue for determining their potential relationships and predictors. Our findings indicated that Ma2-PNS could frequently involve the peripheral nervous system, MM might be one of its associated cancers with a presentation of chronic SMN, and FAMD might be a clinically valuable tool.

Anti-Ma encephalitis masquerading as Wernicke encephalopathy.

BACKGROUND: Anti-Ma encephalitis is a disease usually associated with testicular cancer in young male patients. Anti-Ma encephalitis presented as Wernicke encephalopathy-like symptoms and with gastric cancer is rare. Here, we report a case of anti-Ma encephalitis with gastric cancer in an elderly patient, which has been misdiagnosed of Wernicke encephalopathy. CASE REPORT: A 71-year old male with a history of alcohol abuse was admitted to the hospital because of progressive dizziness, diplopia and anorexia lasted for 1 month. He was initially diagnosed as Wernicke encephalopathy. However, this patient failed in the treatment of VitB1. The blood and cerebrospinal fluid examination found the presence of anti-Ma1/2 antibodies. 18F-FDG PET-MR showed symmetrical hypermetabolic changes on the bilateral hypothalamus, basal ganglion and brainstem, as well as gastric neoplasms with liver metastasis. The patient was finally diagnosed with anti-Ma encephalitis. CONCLUSION: Anti-Ma encephalitis should be suspected in patient with Wernicke encephalopathy-like symptoms but failed VitB1 treatment.

Motor neuron involvement in anti-Ma2-associated paraneoplastic neurological syndrome.

OBJECTIVE: To present clinical, radiological, and pathological features of a cohort of patients with motor neuron involvement in association with anti-Ma2 antibodies (Ma2-Ab). METHODS: Retrospective case-series of patients with definite paraneoplastic neurological syndrome (PNS) and Ma2-Ab, and cases identified from a review of the literature. RESULTS: Among 33 Ma2-Ab patients referred between 2002 and 2016, we retrospectively identified three patients (9.1%) with a motor neuron syndrome (MNS). Seven additional cases were retrieved among the 75 Ma2-patients reported in the literature (9.3%). A total of ten patients are, therefore, described herein. MNS was evident as combined upper and lower MNS in four patients, isolated upper MNS in two, and isolated lower MNS in one; three patients were diagnosed with myeloradiculopathy. The most common MNS signs/symptoms were: hyperreflexia (80%), proximal weakness (60%), proximal upper-limb fasciculations (50%), head drop (40%), and dysarthria/dysphagia (30%). Brain MRI abnormalities included bilateral pyramidal tract T2-weighted/FLAIR hyperintensities (three patients). Spine MRI found bilateral, symmetric, T2-weighted signal abnormalities in the anterior horn in two patients. CSF examination was abnormal in nine patients. Cancer was found in seven patients (four testicular, two lung, and one mesothelioma). Eight patients underwent first-line immunotherapy. Second-line immunotherapy was adopted in all our patients and in none of those identified in the literature. Motor improvement was observed in 33% of our patients, and 20% in the literature series. CONCLUSIONS: Motor neuron involvement could complicate Ma2-Ab-associated PNS in almost 10% of patients and must be carefully studied to adapt treatment. This disorder differs from amyotrophic lateral sclerosis.

Anti-Ma and anti-Ma2-associated paraneoplastic neurological syndromes. / Síndromes neurológicos paraneoplásicos asociados a anticuerpos anti-Ma y anti-Ma2.

OBJECTIVE: Analyse the clinical profile, associated tumour types, and response to treatment of paraneoplastic neurological syndromes associated with antibodies against Ma proteins. METHODS: A retrospective study of patients with antibodies against Ma proteins identified in a neuroimmunology laboratory of reference. RESULTS: Of the 32 patients identified, 20 showed reactivity against Ma2 only (anti-Ma2 antibodies), 11 against Ma1 and Ma2 (anti-Ma antibodies), and 1 with reactivity against Ma1 only (anti-Ma1 antibodies). The most common clinical presentations were limbic encephalopathy, diencephalic dysfunction, or brainstem encephalopathy, frequently appearing as a combination of these features. Three patients had isolated cerebellar dysfunction with anti-Ma antibodies, and 2 exhibited peripheral nervous system syndrome with anti-Ma2 antibodies. Testicular tumours were the most common neoplasms (40%) in the anti-Ma2 cases. In the group associated with anti-Ma1 antibodies, the most common were lung tumours (36%), followed by testicular tumours. All idiopathic cases were reactive to Ma2. The clinical outcome was significantly better in the anti-Ma2 group. The patient with anti-Ma1 presented with limbic encephalitis and brainstem dysfunction associated with lymphoepithelioma of the bladder. CONCLUSIONS: Specifically determining the different reactivities of anti-Ma protein antibodies in order to differentiate between Ma1 and Ma2 antibodies is important because anti-Ma2-associated paraneoplastic syndromes have a better outcome. Lastly, this study is the first to confirm that there may be cases that react exclusively to antibodies against Ma1.

Severe dysautonomia as a main feature of anti-GAD encephalitis: Report of a paediatric case and literature review.

INTRODUCTION: Anti-glutamic acid decarboxylase (anti-GAD65) antibodies are a rare cause of autoimmune encephalitis. This entity is mainly recognized in adults and very few cases were reported in children. We report on a paediatric case of anti-GAD encephalitis with severe presentation and uncontrollable dysautonomia. CASE STUDY: A 9-year-old girl was referred to our department for refractory seizures and behavioral disturbances. Brain magnetic resonance imaging (MRI) was normal. Repeat screening for antineuronal antibodies showed negative results for anti-NMDA receptor antibodies but positive results for anti-GAD65 with a low positivity of anti-Ma2 antibodies. Although a transient improvement was noticed after immunomodulatory treatment, the patient developed severe intractable autonomic imbalance including dysrythmia, alternating bradycardia/tachycardia, hypotension/hypertension, hypothermia/hyperthermia and hyperhidrosis. She deceased six months after onset. CONCLUSION: Our report intends to raise awareness of autoimmune encephalitis with anti-GAD65 antibodies which may involve extralimbic brain regions and manifest with fatal dysautonomia. We highlight the need for prompt diagnosis and aggressive management for this underdiagnosed entity in children.

Anti-MA2 autoinmune encephalitis: A unique case report and narrative concise review

Anti-Ma-2 encephalitis is a rare autoimmune condition which can display a wide range of neuropsychiatric symptoms. It is usually paraneoplastic as 96% of the cases are linked to the presence of a tumor, mainly testicular or pulmonary. Many of these patients can usually be misdiagnosed psychiatrically months before the proper diagnosis is set. Diagnostic battery tests must be exhaustive and treatment includes several lines of medications and treatment of the primary tumor, which determines severe but better prognosis than the rest of autoimmune encephalitic processes. Herein, we present a paradigmatic and almost unique clinical case of a 51-year-old man who was affected of this condition, suffering from left hemichorea, cerebellar and limbic symptoms. The symptomatology had been refractory to several treatment lines and no hidden tumor was detected. The case is accompanied by a narrative concise review of this condition. The wide range of symptomatology displayed, often preceding tumor diagnosis and its severe prognosis make essential to suspect these autoimmune entities when facing neuropsychiatric unusual and complex clinical pictures. Only two previous cases of Anti-Ma 2 encephalitis have been described before with these clinical manifestations, one in Iran and the other one in Germany. (AU)

La encefalitis Anti Ma-2 es una situación autoinmune rara que puede mostrar una amplia gama de síntomas neuropsiquiátricos, que son normalmente paraneoplásicos, ya que el 96% de los casos está vinculado a la presencia de un tumor, principalmente testicular o pulmonar. Normalmente muchos de estos pacientes reciben un diagnóstico psiquiátrico erróneo meses antes de que el diagnóstico adecuado sea establecido. La batería de pruebas diagnósticas debe ser exhaustiva, debiéndose incluir diversas líneas farmacológicas y el tratamiento del tumor primario, que determina un pronóstico grave aunque mejor que el resto de procesos de encefalitis autoinmunes. Presentamos aquí un caso paradigmático y casi único de un varón de 51 años afectado de esta situación, que padecía hemicorea izquierda, y síntomas cerebelares y límbicos. La sintomatología había sido refractaria a diversas líneas de tratamiento, no habiéndose detectado ningún tumor. El caso se acompaña de una revisión concisa narrativa de esta situación. La amplia gama de sintomatología exhibida que precede a menudo al diagnóstico del tumor, así como la gravedad de su pronóstico, hacen que sea fundamental sospechar estas entidades autoinmunes a la hora de enfrentarse a cuadros clínicos neuropsiquiátricos inusuales y complejos. Solo se han descrito anteriormente dos casos de encefalitis Anti-Ma 2 previos a estas manifestaciones clínicas: uno en Irán y otro en Alemania. (AU)

An 8-year old boy with continuous spikes and waves during slow sleep presenting with positive onconeuronal antibodies.

OBJECTIVE: To determine the etiology of epilepsy with continuous spikes and waves during slow sleep (CSWS)/electrical status epilepticus during sleep (ESES) in an 8-year old boy with a history of neuroblastoma and opsoclonus-myoclonus. MATERIAL & METHODS: A combination of clinical characterization and follow-up, video EEG and laboratory investigations. RESULTS: We report the case of an 8-year old boy with a history of neuroblastoma and opsoclonus-myoclonus, who presented with intellectual disability, pharmacotherapy-resistant epilepsy and CSWS/ESES. Although the patient's neuroblastoma had been successfully treated 8 years prior to presentation and an extensive workup did not show a tumor reoccurrence, testing for onconeuronal antibodies was positive for anti-Ma2 and anti-CV2/CRMP5 antibodies. High-dose intravenous methylprednisolone and a taper of oral methylprednisolone were given, leading to a significant clinical improvement. During the taper the patient's condition and EEG manifestations deteriorated again necessitating another cycle of steroid therapy, which lead to a stable improvement. During a 6-month follow-up no CSWS/ESES was seen on EEG and anti-Ma2 and anti-CV2/CRMP5 antibodies remained undetectable. CONCLUSION: This case suggests that onconeuronal antibodies may be involved in the pathogenesis of CSWS/ESES.

Anti-Ma2-encephalitis in a 2 year-old child: A newly diagnosed case and literature review.

BACKGROUND: Anti-Ma2-associated encephalitis is a rare paraneoplastic neurological syndrome characterized by isolated or combined limbic, diencephalic, or brainstem dysfunction. It is rarely reported in children. CASE STUDY: We describe the clinical data of a 2-year-old girl referred to our department for refractory focal seizures associated with fever, followed by behavioural changes, speech disturbances and confusional episodes. Brain magnetic resonance imaging (MRI) showed left temporoparietal brain involvement. Haematological, biochemical and infectious evaluations were unremarkable. Autoimmune encephalitis was suspected. Paraneoplastic antibodies tests showed positive results for anti-Ma2 antibodies. Screening for underlying tumour was negative. Immunomodulatory treatment was administrated. The patient showed improvement of vigilance and behaviour. However, she kept refractory epilepsy. CONCLUSION: Although poor response to immunotherapy, early diagnosis and appropriate treatment of this disorder may prevent irreversible sequelae.