Hu Antibodies Research Articles

Frequency and Referral Patterns of Neural Antibody Studies During the COVID-19 Pandemic: Experience From an Autoimmune Neurology Center.

To determine whether the frequency of paraneoplastic or autoimmune encephalitis antibodies examined in a referral center changed during the COVID-19 pandemic. The number of patients who tested positive for neuronal or glial (neural) antibodies during pre-COVID-19 (2017-2019) and COVID-19 (2020-2021) periods was compared. The techniques used for antibody testing did not change during these periods and included a comprehensive evaluation of cell-surface and intracellular neural antibodies. The chi-square test, Spearman correlation, and Python programming language v3 were used for statistical analysis. Serum or CSF from 15,390 patients with suspected autoimmune or paraneoplastic encephalitis was examined. The overall positivity rate for antibodies against neural-surface antigens was similar in the prepandemic and pandemic periods (neuronal 3.2% vs 3.5%; glial 6.1 vs 5.2) with a mild single-disease increase in the pandemic period (anti-NMDAR encephalitis). By contrast, the positivity rate for antibodies against intracellular antigens was significantly increased during the pandemic period (2.8% vs 3.9%, p = 0.01), particularly Hu and GFAP. Our findings do not support that the COVID-19 pandemic led to a substantial increase of known or novel encephalitis mediated by antibodies against neural-surface antigens. The increase in Hu and GFAP antibodies likely reflects the progressive increased recognition of the corresponding disorders.

Novel Cell-Based Assay for Alpha-3 Nicotinic Receptor Antibodies Detects Antibodies Exclusively in Autoimmune Autonomic Ganglionopathy.

Background and ObjectivesAutoantibodies against α3-subunit–containing nicotinic acetylcholine receptors (α3-nAChRs), usually measured by radioimmunoprecipitation assay (RIPA), are detected in patients with autoimmune autonomic ganglionopathy (AAG). However, low α3-nAChR antibody levels are frequently detected in other neurologic diseases with questionable significance. Our objective was to develop a method for the selective detection of the potentially pathogenic α3-nAChR antibodies, seemingly present only in patients with AAG.MethodsThe study involved sera from 55 patients from Greece, suspected for autonomic failure, and 13 patients from Italy diagnosed with autonomic failure, positive for α3-nAChR antibodies by RIPA. In addition, sera from 52 patients with Ca2+ channel or Hu antibodies and from 2,628 controls with various neuroimmune diseases were included. A sensitive live cell-based assay (CBA) with α3-nAChR–transfected cells was developed to detect antibodies against the cell-exposed α3-nAChR domain.ResultsTwenty-five patients were found α3-nAChR antibody positive by RIPA. Fifteen of 25 patients were also CBA positive. Of interest, all 15 CBA-positive patients had AAG, whereas all 10 CBA-negative patients had other neurologic diseases. RIPA antibody levels of the CBA-negative sera were low, although our CBA could detect dilutions of AAG sera corresponding to equally low RIPA antibody levels. No serum bound to control-transfected cells, and none of the 2,628 controls was α3-CBA positive.DiscussionThis study showed that in contrast to the established RIPA for α3-nAChR antibodies, which at low levels is of moderate disease specificity, our CBA seems AAG specific, while at least equally sensitive with the RIPA. This study provides Class II evidence that α3-nAChR CBA is a specific assay for AAG.Classification of EvidenceThis study provides Class II evidence that an α3-nAChR cell-based assay is a more specific assay for AAG than the standard RIPA.

Autoimmune and Paraneoplastic Chorea: A Review of the Literature.

Autoimmune chorea syndromes represent a vast array of paraneoplastic, parainfectious and idiopathic disorders. It is increasingly apparent that familiarity with these disorders is critically important, as they may be treatable or may be part of a syndrome requiring further work-up and monitoring. These disorders are mediated by an aberrant immunologic attack with resultant neuronal dysfunction, manifesting as chorea. These conditions are typically accompanied by other neurologic or systemic manifestations. In this review we outline the clinical features, epidemiologic factors, and delineate the specific antibodies associated with each of these autoimmune mediated disorders. We highlight up to date information regarding this heterogeneous group of disorders, including a discussion of parainfectious Sydenham's chorea; paraneoplastic syndromes associated with CRMP-5 (collapsin response mediated protein-5/CV2) and ANNA-1 (antineuronal nuclear antibody / Hu) antibodies, in addition to neuronal antibody-associated disorders including anti-NMDAR, LGI1 (leucine-rich glioma inactivated-1) and CASPR2 (contactin associated protein-2). We discuss the more recently described entities of IgLON5, which has evidence of both immunologic and degenerative pathophysiology, in addition to PDE-10A antibody-associated chorea. We also outline chorea secondary to systemic diseases including Systemic Lupus Erythematosus (SLE) and Primary Antiphospholipid Syndrome (PAPS). We provide a framework for diagnosis and treatment.

Serum antiganglioside antibodies in patients with autoimmune limbic encephalitis.

Ganglioside antibodies are identified not only in patients with inflammatory neuropathies but also several central nervous system disorders and paraneoplastic neuropathies. Our aim was to investigate whether ganglioside antibodies are found in autoimmune encephalitis patients and may function as a diagnostic and prognostic biomarker. Sera and cerebrospinal fluid (CSF) samples of 33 patients fulfilling the criteria for probable autoimmune encephalitis were collected within the first week of clinical manifestation. None of the patients had evident symptoms and findings of peripheral polyneuropathy. Well-characterized antineuronal and paraneoplastic antibodies were investigated in sera and CSF and antiganglioside (antiGM1, GM2, GM3, GD1a, GD1b, GT1b, and GQ1b) IgG and IgM antibodies were measured in sera using commercial immunoblots. Twenty-eight of 33 autoimmune encephalitis patients displayed antibodies against neuronal surface or onco-neural antigens with N-methyl-D-aspartate receptor (NMDAR), glutamic acid decarboxylase (GAD) and Hu antibodies being the most prevalent. While no antiganglioside IgG antibodies were found, 4 patients (2 anti-NMDAR+, 1 anti-GAD+ and 1 antibody negative) with autoimmune limbic encephalitis displayed anti-GM1, anti-GM2, anti-GM3 or anti-GQ1b IgM antibodies. There was no apparent association between antiganglioside positivity and clinical and demographic features. Serum ganglioside IgM antibodies may infrequently emerge during the clinical course of autoimmune limbic encephalitis without evident polyneuropathy. Absence of the IgG response suggests that these antibodies might have developed as a hyperacute immune response to neuro-axonal destruction. Nevertheless, potential impact of ganglioside antibodies on axonal degeneration and neuronal loss in limbic encephalitis pends to be further investigated.

Limbic Encephalitis with HU-Antibodies in T-cell Anaplastic Lymphoma. A Case Report

Limbic encephalitis is a rare paraneoplastic neurological syndrome usually associated with small cell lung cancers, testicular and breast cancers or B-cell lymphomas. We herein report the first patients with paraneoplastic limbic encephalitis associated with HU antibodies and anaplastic T-cell lymphoma.

Autoimmune Encephalitis: Current Knowledge on Subtypes, Disease Mechanisms and Treatment.

Autoimmune Encephalitides (AE) comprises a group of diseases with antibodies against neuronal synaptic and cell surface antigens. Since the discovery of the most common subtype, NMethyl- D-Aspartate (NMDA) receptor encephalitis, an astonishing number of novel disease-causing antibodies have been described. This includes other glutamatergic and GABAergic receptor antibodies and antibodies against various other surface proteins. Many of these novel conditions present as limbic encephalitis with memory impairment, psychiatric features and epileptic seizures, often alongside subtype specific clinical features. Others present with a clinical disease course specific to the antibody. In contrast to the well-known paraneoplastic syndromes with antibodies directed against intracellular antigens (e.g. limbic encephalitis with Hu antibodies), autoimmune encephalitides are often highly responsive to immunotherapy, with a good outcome if diagnosed and treated early. Prognosis depends on aggressive immunotherapy, often with a combination of corticosteroids, intravenous immunoglobulin, plasma exchange or in some cases anti-CD20 therapy and cyclophosphamide. Other treatment regimens exist, and prognosis varies between disease subtypes and occurrence of underlying cancer. We review current knowledge on subtype-specific clinical presentation, disease mechanisms, diagnosis including pitfalls, treatment paradigms and outcome in autoimmune encephalitides, and provide suggestions for future research.

A paraneoplastic limbic encephalitis from an anorectal small cell neuroendocrine carcinoma: a case report

BackgroundParaneoplastic limbic encephalitis (PLE) is a rare autoimmune neurological syndrome observed in cancer patients. PLE is difficult to diagnose and presents a variable response to treatment, depending on the characteristics of the tumor and neuronal autoantibodies.Case presentationA 64-year-old, Caucasian, non-smoker man presented with a rapidly developing cognitive impairment, personality change, spatial disorientation, and short-term memory loss associated with anorexia and cervical and inguinal lymph nodes. The 18F-FDG PET scan documented intensely hypermetabolic lymph nodes, which histologically corresponded to a metastasis from a small cell neuroendocrine carcinoma. The brain MRI revealed a high T2-weighted FLAIR signal of the hippocamps, consisted with a PLE. The presence of anti-neuronal Hu antibodies confirmed the diagnosis. The patient underwent plasmapheresis, associated to a systemic chemotherapy resulting in a partial and temporary improvement of the neurological symptoms. Four cycles of intravenous immunoglobulins were also necessary. After six cures of chemotherapy, the lymph node metastases regressed. However, a new anorectal lesion was detected and was histologically confirmed as a primary small cell neuroendocrine carcinoma, which was treated with concomitant chemoradiotherapy. At the end of this treatment, the patient showed a rapid tumor progression leading to his death.ConclusionsThis case highlights the rare entity, PLE, which is difficult to diagnose and manage. In addition, this is the first published case of PLE associated with an anorectal small cell neuroendocrine carcinoma, which appeared after completion of systemic chemotherapy.

The expanded clinical spectrum of anti-GABABR encephalitis and added value of KCTD16 autoantibodies.

In this study we report the clinical features of 32 patients with gamma aminobutyric acid B receptor (GABABR) antibodies, identify additional autoantibodies in patients with anti-GABABR encephalitis that mark the presence of an underlying small cell lung carcinoma and optimize laboratory methods for the detection of GABABR antibodies. Patients (n = 3225) were tested for the presence of GABABR antibodies using cell-based assay, immunohistochemistry and live hippocampal neurons. Clinical data were obtained retrospectively. Potassium channel tetramerization domain-containing (KCTD)16 antibodies were identified by immunoprecipitation, mass spectrometry analysis and cell-based assays. KCTD16 antibodies were identified in 23/32 patients with anti-GABABR encephalitis, and in 1/26 patients with small cell lung carcinoma and Hu antibodies, but not in 329 healthy subjects and disease controls. Of the anti-GABABR encephalitis patients that were screened sufficiently, 18/19 (95%) patients with KCTD16 antibodies had a tumour versus 3/9 (33%) anti-GABABR encephalitis patients without KCTD16 antibodies (P = 0.001). In most cases this was a small cell lung carcinoma. Patients had cognitive or behavioural changes (97%) and prominent seizures (90%). Thirteen patients developed a refractory status epilepticus with intensive care unit admittance (42%). Strikingly, 4/32 patients had a rapidly progressive dementia. The addition of KCTD16 to the GABABR cell-based assay improved sensitivity of the in-house fixed cell-based assay, without loss of specificity. Twenty-two of 26 patients improved (partially) to immunotherapy or chemotherapy. Anti-GABABR encephalitis is a limbic encephalitis with prominent, severe seizures, but patients can also present with rapidly progressive dementia. The co-occurrence of KCTD16 antibodies points towards a paraneoplastic origin. The addition of KCTD16 improves the sensitivity of the cell-based assay.

Paraneoplastic limbic encephalitis associated with lung cancer

Paraneoplastic limbic encephalitis (PLE) is a rare autoimmune neurological syndrome observed in lung cancer patients. We retrospectively investigated the clinical characteristics, treatment responses, and prognoses in 16 PLE patients who were subsequently diagnosed with lung cancer. Fifteen patients initially presented with disturbance of consciousness, 13 with disorientation, and 12 with seizures. Thirteen patients had autoantibodies, including eight with gamma aminobutyric acid B receptor (GABABR) antibodies and eight with Hu antibodies. PET-CT revealed lung neoplasms in 13 patients, nine of whom exhibited abnormal metabolic activity in the temporal lobe and hippocampus. Fifteen cases were confirmed as limited-stage small cell lung cancer and one as stage IV large cell neuroendocrine carcinoma. Eleven patients received immunomodulatory therapy, and four showed neurological improvement, who all had antibodies against GABABR. Fifteen patients received chemotherapy, of which 14 maintained or improved their PLE status. The overall cancer response rate was 75%, and two-year overall survival was 74.7%. Our results suggest patients with GABAB encephalitis might respond better to immunotherapy than the classical PLE patients with anti-Hu antibodies. Anti-cancer treatment could further improve neurological symptoms. Lung cancer patients with PLE, especially those in limited stage, might have better outcome due to earlier diagnosis and prompt anti-cancer treatment.

Immunoadsorption or plasma exchange in the treatment of autoimmune encephalitis: a pilot study.

Therapeutic apheresis has emerged as a major treatment option for autoantibody-associated inflammatory diseases of the nervous system. This includes patients with autoimmune encephalitides caused by antibodies against neuronal proteins. Plasma exchange (PE) and immunoadsorption (IA) constitute two possibilities to eliminate pathogenic antibodies from patients' plasma, but their efficacy and safety has not been prospectively assessed in larger patient groups of autoimmune encephalitides. In a prospective observational case control study, we, therefore, investigated the disease courses and treatment effects of 21 patients with autoimmune encephalitis associated with NMDAR, LGI1, CASPR2, GAD, mGluR5 and Hu antibodies. Patients were randomly assigned to receive PE (n=11) or IA (n=10). Symptoms were evaluated using the modified Rankin Scale (mRS). Side effects or adverse events were recorded. Both interventions, IA (p=0.014) and PE (p=0.01), resulted in significant reduction of the median mRS. With IA, 60% of the patients improved clinically by at least 1 mRS score, none worsened. PE led to a comparable symptom reduction in 67% of the cases. During 83 PE sessions, three adverse events were documented, while no side effects occurred under IA. Symptom improvement was significantly associated with younger age (r=-0.58), but not with disease duration. Therapeutic apheresis was most effective for neuronal surface antigens (83.3%), followed by intracellular-synaptic antigens (66.7%). Both IA and PE resulted in moderate to marked clinical improvement, with a low rate of adverse events. Apheresis is well tolerated and effective also as first-line therapy in autoimmune encephalitis, particularly in patients with antibodies targeting neuronal surfaces.

Autoantibody diversity in paraneoplastic syndromes and related disorders: The need for a more guided screening approach

BackgroundSignificant progress has been made in understanding the role and diversity of autoantibodies in the pathogenesis, diagnosis and management of paraneoplastic syndrome (PNS) and related autoimmune neurologic diseases. We evaluated the positivity rates for diverse autoantibody panels to rationalize testing strategies and utilization. MethodsThe result patterns for different autoantibody panels for PNS offered at 2 reference laboratories in the U.S. were retrospectively reviewed for the same period. The positivity rates were evaluated and compared for specific autoantibodies within panels offered at both laboratories. ResultsFor the Hu, Ri, Yo, and amphiphysin antibodies offered by both laboratories, no significant difference in positivity rates was observed. The positivity rates for non-classic PNS markers were 0% [AGNA and PCCA-Tr], and 0.06% [ANNA-3 and PCAC-2] while the prevalence of antibodies associated with neuromuscular autoimmunity varied from 1.40% to 4.44% [Striated muscle, AChR binding, ganglionic AChR, VGCC, P/Q- and N-type VGCC]. ConclusionsThe data suggest that test utilization could be substantially improved based on ordering practice geared towards clinical manifestations and prevalence of autoantibodies. Concerted efforts towards streamlining diagnostic algorithms based on risk, clinical manifestations, characterization of autoantibodies and their associations as well as therapeutic strategies are needed.

Prostate cancer, Hu antibodies and paraneoplastic neurological syndromes.

Prostate cancer is the most common cancer among American and European men. Nervous system affection caused by local tumor growth or osseous metastases are the main causes of neurological symptoms in prostate cancer patients. Prostate cancer is rarely reported in association with paraneoplastic neurological syndromes (PNS). We have, therefore, studied clinical and paraclinical findings of a series of patients with prostate cancer and PNS, and reviewed cases reported in the literature. Case histories of 14 patients with definite PNS from the PNS Euronetwork database and from the authors' databases were reviewed. A PubMed literature search identified 23 patients with prostate cancer and PNS. Thus, a total of 37 case histories were reviewed with respect to syndrome type, cancer evolution, paraclinical investigations, antibody status, treatment and outcome. The three most frequent isolated PNS were paraneoplastic cerebellar degeneration, paraneoplastic encephalomyelitis (PEM)/limbic encephalitis and subacute sensory neuronopathy (SSN). Onconeural antibodies were detected in 23 patients, in most cases the Hu antibody (17 patients, 74% of all antibody-positive cases). Other well-characterized onconeural antibodies (Yo, CV2/CRMP5, amphiphysin, VGCC antibodies) were found in a minority. PNS was diagnosed prior to prostate cancer diagnosis in 50% of the cases. The association of PNS with prostate cancer is quite infrequent, but clinically important. PNS often heralds prostate cancer diagnosis. Syndromes associated with Hu antibodies predominate. Another tumor more prone to associate with PNS should always be excluded.

G65(P) Neuropsychiatric presentation of antibody negative limbic encephalitis

Autoimmune encephalitis is an increasingly recognised cause for a combination of symptoms of seizures, disturbance of memory, behaviour and cognition. Other manifestations include acute onset movement disorders, unexplained encephalopathy and refractory status epilepticus. N-methyl aspartate (NMDA) encephalitis and voltage gated potassium channel mediated (VGKC) limbic encephalitis are the two commonest causes of autoimmune encephalitis. These children initially present to general paediatricians therefore it is vital to consider this in the differential diagnosis of infective encephalitis as prompt recognition, investigation and immune therapy determines longterm outcome. Early recognition and treatment can potentially halt temporal lobe atrophy and improve outcome. We report a 14 year old girl who presented with symptomatic, intermittent memory loss, behaviour disturbance, fatigue and cognitive change with limbic encephalitis. Initial investigations revealed negative PCR for HSV, EBV. Brain imaging detected mesial right temporal high signal area in FLAIR sequences. EEG showed epileptic inter-ictal focal abnormality over right frontal mesial temporal region. NMDA, VGKC, Anti GAD, Hu, Ma, CV2, CRMP5 and thyroid antibodies were negative. Screening for tumour with baseline abdominal ultrasound and CXR were negative. Baseline WISC testing prior to starting medications revealed her immediate memory for verbal information was in the low average range (verbal immediate index score:82,12th percentile) and her time delayed recall verbal information was in the impaired range (verbal delayed index score:72, 3rd percentile). She was treated with iv methylprednisolone followed by tapering dose of oral prednisolone. Repeat WISC assessment is due in 6 months. Limbic encephalitis should be considered in children with prominent neuropsychiatric manifestation of encephalitis. Her future MRI reports will determine the 3 month and 6 month outcome for this teenager. Longterm surveillance for tumour detection is recommended in autoimmune encephalitis.

Imbalance in circulating T lymphocyte subsets contributes to Hu antibody-associated paraneoplastic neurological syndromes

Paraneoplastic neurological syndromes (PNS) are associated with small cell lung cancer (SCLC) and Hu antibodies, which are considered to have an immune-mediated etiology. As a pathogenic role for Hu antibodies (Hu-Ab) in PNS could not be demonstrated, the cellular immune response against the Hu proteins has been further investigated. To delve deeper into the hypothesized cell-mediated immune pathogenesis of these syndromes, imbalances within circulating T lymphocyte subsets were investigated to determine their significance in Hu antibody-associated PNS. The circulating T lymphocyte subsets were analyzed in untreated patients with SCLC, PNS and Hu-Ab (n=10), SCLC without PNS (n=10) and healthy controls (n=12) using flow cytometry. Patients with PNS and SCLC, had a variety of changes within their circulating T lymphocyte subsets, which included; lymphopenia of the CD3+and CD4+ T cells, increased proportions of total activated T cells and activated CD4+ T cells, and reduced numbers of CD4+ and CD25+ regulatory T cells (Treg). These results suggest that the excessive activation of T cells and dysfunction of Treg contribute to Hu antibody-associated PNS.

Small-cell lung cancer with voltage-gated calcium channel antibody-positive paraneoplastic limbic encephalitis: a case report

IntroductionParaneoplastic limbic encephalitis is a rare neurological syndrome and clinically characterized by cognitive dysfunction, memory impairment, seizures and psychiatric symptoms. Paraneoplastic limbic encephalitis is most frequently found in small-cell lung cancer, among various malignancies, and antineuronal antibodies are related to the autoimmune mechanism. We experienced a rare case of a patient with small-cell lung cancer with anti-voltage-gated calcium channel antibody-positive paraneoplastic limbic encephalitis.Case presentationA 61-year-old Japanese man with a history of smoking cigarettes presented with seizure, confusion and personality change in acute onset. Brain magnetic resonance imaging showed high signal intensity on T2-weighted image in his right temporal lobe, suggestive of limbic encephalitis. A mediastinoscopy of the lymph node revealed small-cell lung carcinoma, and he was staged as having limited stage disease. Antibodies against P/Q-type and N-type voltage-gated calcium channel were positive and Hu antibody was negative. He was started on chemotherapy of carboplatin plus etoposide with concurrent thoracic radiotherapy. Neurological symptoms were gradually improved after systemic chemotherapy.ConclusionsWe should be alert to the potential of malignant neoplasms associated with paraneoplastic limbic encephalitis when we examine a patient with cancer with neurological disorders such as personality change, disorientation, unconsciousness and memory loss. A clinical marker such as voltage-gated calcium channel antibody may help our diagnosis in clinical practice.

Paraneoplastic Hu and CRMP5 antibodies are present in smokers without cancer or neurological disease

We investigated if the paraneoplastic Hu and collapsin response mediator protein 5 (CRMP5) antibodies could be used as early markers for lung cancer in smokers with or without chronic obstructive pulmonary disease (COPD). Hu and CRMP5 antibodies were measured by radioimmunoprecipitation assay (RIPA) in sera from 552 smokers; 379 with and 173 without COPD. Three hundred blood donors served as controls. The positive sera were also tested by indirect immunofluorescence and line blot with recombinant proteins. The 552 smokers were matched with data from the Cancer Registry of Norway, and the hospital medical records from the subjects positive for Hu and CRMP5 antibodies were reviewed. The mean follow-up time was 4.4 years (range 2.5-5.7 years). The RIPA showed that 5/379 (1.3%) smokers with COPD had Hu antibodies and 1/379 (0.3%) smokers with COPD had CRMP5 antibodies. Only the smoker with the highest RIPA index had Hu antibodies also detected by immunofluorescence and line blot. One of 173 (0.6%) smokers without COPD had Hu antibodies, but none had CRMP5 antibodies. None of the 300 controls had Hu antibodies, but 2/300 (0.7%) had CRMP5 antibodies. Hu antibodies remained positive for more than 5 years. No cancer or neurological disease was recorded in the Hu or CRMP5 positive patients. The total cancer frequency in the smokers with and without COPD was 70/552 (13%). Hu and CRMP5 antibodies were not associated with cancer or neurological disease in a large cohort of smokers and are therefore not always paraneoplastic.

PARANEOPLASTIC LIMBIC ENCEPHALITIS AND LAMBERT EATON MYASTHENIA–AN IMMUNOLOGICAL PROFILE OF A NEW SYNDROME?

We report a case of paraneoplastic limbic encephalitis (LE) and Lambert Eaton myasthenic Syndrome (LEMS) with a novel immunological onco–neural profile: Voltage Gated Calcium Channel (VGCC) antibodies, high titre Voltage...

Avidity of onconeural antibodies is of clinical relevance.

Onconeural antibodies are important in the detection of paraneoplastic neurological syndromes (PNS). The avidity of Hu, Yo, and CRMP5 antibodies from 100 patients was determined by immunoprecipitation (IP), and 13 of the Yo positive sera were also tested by surface plasmon resonance (SPR). There was a significant association between the results from IP and SPR. Yo antibodies had higher avidity than Hu and CRMP5 antibodies, and both high- and low-avidity antibodies were associated with tumors and PNS. High-avidity Yo antibodies were mainly associated with ovarian cancer, whereas high-avidity Hu and CRMP5 antibodies were mainly associated with small-cell lung cancer. Low-avidity CRMP5 and Yo antibodies were less often detected by a commercial line blot than high-avidity antibodies. The failure to detect low-avidity onconeural antibodies may result in under diagnosis of PNS.

Paraneoplastic limbic encephalitis, an uncommon presentation of a common cancer: Case report and discussion

Patient: Female, 59Final Diagnosis: Paraneoplastic limbic encephalitisSymptoms: Seizure • memory changes • decreased concentrationMedication: ChemotherapyClinical Procedure: Cerebral imagesSpecialty: Hematology • OncologyObjective:Challenging differential diagnosisBackground:Paraneoplastic neurological disorders (PND) are defined as remote effects on the nervous system that are not caused directly by the tumor, its metastases, or metabolic disruptions. This syndrome occurs in less than 1 per 10,000 patients diagnosed with a malignancy. Many antibodies are found in the central nervous system in PND, the most well known are Anti-Hu, Tr, CV2 Ta, Yo, Ri and amphiphysin. Paraneoplastic limbic encephalitis occurs due to involvement of the limbic system secondary to an autoimmune response to neurons of the brain provoked by the antibodies. Patients, thus, present with seizures, changes in mood, memory, and personality.Case Report:Fifty-nine years-old female patient presented with seizures, decreased concentration and memory changes. Laboratory workup was remarkable for hyponatremia. Further workup included brain computerized tomography (CT) and magnetic resonance imaging (MRI), which suggested a diagnosis of encephalitis for limbic encephalitis. Anti-Hu, anti-Ma and NMDA-receptor antibodies were requested of which Anti Hu antibodies were positive. Transbronchial biopsy was obtained which confirmed the diagnosis of small cell lung cancer.Conclusions:A very high index of suspicion should thus be present when patients present with paraneoplastic abnormalities. It must be emphasized that limbic encephalitis (LE) occurs at an early stage of the disease development and therefore the detection of paraneoplastic LE can lead to a quicker identification of the underlying malignancy and a better outcome.

CNS autoimmunity: new findings and pending issues

CNS autoimmunity: new findings and pending issues