Paraneoplastic limbic encephalitis presenting as a neurological emergency: a case report

Clinical Presentation and Outcome in Autoimmune Encephalitis Associated With N-Type Voltage-Gated Calcium Channels in Children

OBJECTIVE

We present the diagnostic and clinical course of the first multicenter case series of pediatric patients with autoimmune encephalitis associated with N-type voltage-gated calcium channel antibodies.

METHODS

Data from 2 university hospitals were retrospectively reviewed and records of 3 patients with autoimmune encephalitis associated with N-type voltage-gated calcium channel antibodies were evaluated.

RESULTS

The 3 pediatric patients (all female) had symptoms that spanned the clinical spectrum. All 3, however, had regression of expressive language and agitation. Neuroimaging in all 3 patients was normal; electroencephalographic (EEG) findings varied among the 3 patients. Positive titers against the N-type voltage-gated calcium channel antibody were found in their cerebrospinal fluid. Following administration of intravenous immunoglobulin, all 3 had improvement in their core presenting symptoms.

CONCLUSION

Autoimmune encephalitis associated with N-type voltage-gated calcium channel antibodies in the pediatric population presents with a wide clinical spectrum, although expressive language delay and agitation seem to be common symptoms. Treatment with intravenous immunoglobulin improves core symptoms.

The role of the laboratory in the expanding field of neuroimmunology: Autoantibodies to neural targets

Accelerated identification of autoantibodies associated with previously idiopathic neurological disease has provided insights into disease mechanisms, enhanced understanding of neurological function, and opportunities for improved therapeutic interventions. The role of the laboratory in the expanding field of neuroimmunology is critical as specific autoantibody identification provides guidance to clinicians in diagnosis, prognosis, tumor search strategies, and therapeutic interventions. The number of specific autoantibodies identified continues to increase and newer testing strategies increase efficiencies in the laboratory and availability to clinicians. The need for broadly targeted efficient testing is underscored by the variability in clinical presentation and tumor associations attributable to a specific autoantibody, and conversely the various autoantibody specificities that can be the cause of a given clinical presentation. While many of the antineural antibodies were first recognized in the setting of neoplastic disease, idiopathic autoimmune neurological disease in the absence of underlying tumor is increasingly recognized. Appropriation of therapeutic modalities used to treat autoimmune disease to treat these autoantibody mediated neurological diseases has improved patient outcomes. Interaction between clinicians and laboratorians is critical to our understanding of these diseases and optimization of the clinical benefits of our increasing knowledge in neuroimmunology.

Autoimmune paraneoplastic syndromes associated to lung cancer: A systematic review of the literature: Part 3: Neurological paraneoplastic syndromes, involving the central nervous system

The development of new immune treatment in oncology and particularly for lung cancer may induce new complications, particularly activation or reactivation of auto-immune diseases. In this context, a systematic review on the auto-immune paraneoplastic syndromes that can complicate lung cancer appears useful. This article is the third of a series of five and deals mainly with neurological paraneoplastic syndromes involving the central nervous system.

Management of neuro-oncologic emergencies

Patients with brain tumors and systemic malignancies are subject to diverse neurologic complications that require urgent evaluation and treatment. These neurologic conditions are commonly due to the tumor's direct effects on the nervous system, such as cerebral edema, increased intracranial pressure, seizures, spinal cord compression, and leptomeningeal metastases. In addition, neurologic complications can develop as a result of thrombocytopenia, coagulopathy, hyperviscosity syndromes, infection, immune-related disorders, and adverse effects of treatment. Patients may present with typical disease syndromes. However, it is not uncommon for patients to have more subtle, nonlocalizing manifestations, such as alteration of mental status, that could be attributed to other systemic, nonneurologic complications. Furthermore, neurologic complications are at times the initial manifestations of an undiagnosed malignancy. Therefore a high index of suspicion is essential for rapid assessment and management. Timely intervention may prolong survival and improve quality of life. In this chapter, we will discuss the common neuro-oncologic emergencies, including epidemiology, pathophysiology, clinical presentation, diagnosis, and treatment.

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

INTRODUCTION

Paraneoplastic 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 PRESENTATION

A 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.

CONCLUSIONS

We 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.

N-type calcium channel antibody-mediated paraneoplastic limbic encephalitis: a diagnostic challenge

BACKGROUND

The etiology of encephalitis presents a diagnostic challenge and often remains a mystery. However, current technological advances using antibodies can enable a definitive diagnosis in cases that would previously have been suspected to be idiopathic or viral encephalitis. Our objective is to show that tonsil neuroendocrine carcinoma can present initially as limbic encephalitis mediated by N-type calcium channel antibodies and to highlight the diagnostic confusion before cancer detection.

METHODS

We report a rare case of neuroendocrine cancer presenting as limbic encephalopathy, Lambert-Eaton myasthenic syndrome and neuropathy. The patient was diagnosed and treated at The University of Texas MD Anderson Cancer Center in November 2011.

RESULTS

Paraneoplastic limbic encephalitis was diagnosed based on clinical presentation of seizures, short-term memory loss, retrograde amnesia, disorientation, distractibility, and abulia; on the exclusion of brain metastases, CNS infection, stroke, metabolic or nutritional deficits, or medication-related events; and on CSF results with inflammatory findings and an abnormal electroencephalography study that showed seizure activity in the left temporal lobe. Serum paraneoplastic panel was positive for P/Q-type calcium channel antibody and N-type calcium channel antibody. Magnetic resonance imaging of brain was unremarkable.

CONCLUSION

This case highlights limbic encephalitis as an atypical presentation of neuroendocrine cancer. It also illustrates how treatment of the underlying cancer can reverse limbic encephalitis and Lambert-Eaton myasthenic syndrome in a neuroendocrine carcinoma patient even before the paraneoplastic panel becomes negative.

N-type calcium channel antibody-mediated autoimmune encephalitis: An unlikely cause of a common presentation

We report, to our knowledge, the only known pediatric case with encephalopathy and significantly elevated titers of N-type voltage-gated calcium channel antibody (N-type VGCC). The patient, an 8th grader, was previously healthy and presented with a one-week history of confusion, aphasia, transient fever, headaches, and dizziness. An underlying autoimmune process was suspected because of inflammatory changes in the brain MRI and multiple focal electrographic seizures captured in the EEG in the absence of CSF pleocytosis. Within 24 h of presentation, the patient was empirically started on immune-modulatory therapy, and a full recovery was achieved within 3 months of the initial presentation. Immune therapy included high-dose intravenous (IV) methylprednisolone followed by a 2-week course of dexamethasone and 2 monthly courses of IV immunoglobulin (IVIG). He was also treated with anticonvulsants for one month. No tumor has been found to date. There is a paucity of reports on autoimmune epilepsy or encephalopathy associated with N-type VGCC. Complete resolution of brain lesion, seizure freedom, and full recovery of function following early and aggressive immunotherapy demonstrate that a high index of suspicion is crucial for early recognition and treatment of autoimmune encephalitis.