Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 31-year old woman died after 10 years of progressive dysautonomia and cerebellar and pyramidal symptoms. CT scan showed pontine, bulbar and cerebellar atrophy. Post-mortem examination revealed Rosenthal's fibers widespread throughout the CNS, but especially in the subependymal and perivascular regions. White matter cavitations involving peri-ventricular regions, hilum of dentate nuclei and pons were observed, leading to a diagnosis of adult form of Alexander's disease. At the age of 5, the patient had been operated upon for a chiasmatic tumor. Microscopic examination revealed a pilocytic astrocytoma without Rosenthal's fibers. No complementary radiotherapy had been done. Her mother has been operated upon in 1972, for a high-grade glioma and is still alive 20 years later. This suggests diffuse cerebral gliomatosis. This family history may suggest a relation between these different diseases. They might be the result of a transmissible astrocytic abnormality with varying expression.
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PMID:[Alexander's disease in adults and diffuse cerebral gliomatosis in 2 members of the same family]. 799 38

This report describes the case of a 49-year-old man who presented to the hospice with severe neuropathic pain, cramps, muscle twitching, generalised sweating, insomnia and anxiety in the context of metastatic thymoma. The symptoms were exquisitely corticosteroid sensitive raising the possibility of an immunogenic aetiology. Morvan's syndrome, a paraneoplastic, immune-mediated syndrome characterised by peripheral nerve hyperexcitability, dysautonomia and central nervous system dysfunction was thus considered. Nerve conduction studies and electromyography were negative as were initial serological assays. Subsequent assays for antibodies to leucine-rich, glioma inactivated one protein and contactin-associated protein-2, recently discovered to be associated with Morvan's syndrome, confirmed the diagnosis. By the time the diagnosis of Morvan's syndrome was reached the patient was too unwell to receive disease-modifying treatments. An awareness of Morvan's syndrome in Palliative and Supportive care is essential to improve the outcome of patients with this devastating syndrome.
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PMID:A complicated case of metastatic thymoma. 2539 17

Voltage-gated potassium channel (VGKC)-complex antibodies are defined by the radioimmunoprecipitation of Kv1 potassium channel subunits from brain tissue extracts and were initially discovered in patients with peripheral nerve hyperexcitability (PNH). Subsequently, they were found in patients with PNH plus psychosis, insomnia, and dysautonomia, collectively termed Morvan's syndrome (MoS), and in a limbic encephalopathy (LE) with prominent amnesia and frequent seizures. Most recently, they have been described in patients with pure epilepsies, especially in patients with the novel and distinctive semiology termed faciobrachial dystonic seizures (FBDS). In each of these conditions, there is a close correlation between clinical measures and antibody levels. The VGKC-complex is a group of proteins that are strongly associated in situ and after extraction in mild detergent. Two major targets of the autoantibodies are leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein 2 (CASPR2). The patients with PNH or MoS are most likely to have CASPR2 antibodies, whereas LGI1 antibodies are found characteristically in patients with FBDS and LE. Crucially, each of these conditions has a good response to immunotherapies, often corticosteroids and plasma exchange, although optimal regimes require further study. VGKC-complex antibodies have also been described in neuropathic pain syndromes, chronic epilepsies, a polyradiculopathy in porcine abattoir workers, and some children with status epilepticus. Increasingly, however, the antigenic targets in these patients are not defined and in some cases the antibodies may be secondary rather than the primary cause. Future serologic studies should define all the antigenic components of the VGKC-complex, and further inform mechanisms of antibody pathogenicity and related inflammation.
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PMID:Voltage-gated potassium channel-complex autoimmunity and associated clinical syndromes. 2711 78

Morvan's syndrome (MoS) is a rare, complex neurological disorder characterized by neuromyotonia, neuropsychiatric features, dysautonomia and neuropathic pain. The majority of MoS cases have a paraneoplastic aetiology, usually occurring prior to the diagnosis of the underlying tumour and showing improvement following its treatment. The present study reports the case of a 35-year-old Caucasian male patient who was diagnosed with stage IVA thymoma. Thymectomy, lung resection, diaphragmatic pleurectomy and pericardio-phrenectomy were performed 6 months after neoadjuvant chemotherapy. The pathological evaluation revealed a type B2-B3 thymoma with focal squamous differentiation. Two years later, the patient underwent new surgical treatment for a local recurrence of the same histological type, and 4 weeks later, the patient presented with complex neurological symptoms compatible with MoS, including neuromyotonia, neuropsychiatric features, dysautonomia and neuropathic pain. Electromyography was compatible with a diagnosis of neuromyotonia. Brain magnetic resonance imaging scan and tests for serum anti-acetylcholine receptor, anti-striated muscle antibodies and anti-30-kDa titin fragment antibodies were all negative, whereas tests for anti-voltage-gated potassium channel (VGKC)-complex antibodies (333.3 pmol/l), anti-leucine-rich glioma inactivated protein 1 and anti-contactin-associated protein-like 2 antibodies were positive. The patient underwent 3 cycles of intravenous administration of immunoglobulins (0.4 g/kg/day for 5 days every 4 weeks) with little clinical and electrophysiological improvement. We speculated that the late onset of the symptoms in the present patient may have been triggered by an increase in the serum level of anti-VGKC antibody, which was caused by the surgery performed for the treatment of recurrent thymoma. To the best of our knowledge, the present report is the first case of MoS associated with this histological type of thymoma uncommonly occurring upon surgical treatment of recurrent thymoma.
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PMID:Paraneoplastic Morvan's syndrome following surgical treatment of recurrent thymoma: A case report. 2769 47

Recent biochemical observations have helped redefine antigenic components within the voltage-gated potassium channel (VGKC) complex. The related autoantibodies may be now divided into likely pathogenic entities, which target the extracellular domains of leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-like 2 (CASPR2), and species that target intracellular neuronal components and are likely non-pathogenic. This distinction has enhanced clinical practice as direct determination of LGI1 and CASPR2 antibodies offers optimal sensitivity and specificity. In this review, we describe and compare the clinical features associated with pathogenic LGI1 and CASPR2 antibodies, illustrate emerging laboratory techniques for antibody determination and describe the immunological mechanisms that may mediate antibody-induced pathology. We highlight marked clinical overlaps between patients with either LGI1 or CASPR2 antibodies that include frequent focal seizures, prominent amnesia, dysautonomia, neuromyotonia and neuropathic pain. Although occurring at differing rates, these commonalities are striking and only faciobrachial dystonic seizures reliably differentiate these two conditions. Furthermore, the coexistence of both LGI1 and CASPR2 antibodies in an individual occurs surprisingly frequently. Patients with either antibody respond well to immunotherapies, although systematic studies are required to determine the magnitude of the effect beyond placebo. Finally, data have suggested that CASPR2 and LGI1 modulation via genetic or autoimmune mechanisms may share common intermediate molecules. Taken together, the biochemical distinction of antigenic targets has led to important clinical advances for patient care. However, the striking syndrome similarities, coexistence of two otherwise rare antibodies and molecular insights suggest the VGKC complex may yet be a common functional effector of antibody action. Hence, we argue for a molecular evolution alongside a clinical and phenotypic re-evaluation.
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PMID:LGI1, CASPR2 and related antibodies: a molecular evolution of the phenotypes. 2905 2

Voltage-gated potassium channel (VGKC) complex auto-antibodies were initially identified in Isaacs' syndrome (IS), which is characterized by muscle cramps and neuromyotonia. These antibodies were subsequently identified in patients with Morvan's syndrome (MoS), which includes IS in conjunction with psychosis, insomnia, and dysautonomia. The antibodies have also been detected in a patient with limbic encephalopathy (LE) presenting with prominent amnesia and frequent seizures. Typical cases of LE have adult-onset, with frequent, brief dystonic seizures that predominantly affect the arms and ipsilateral face, and has recently been termed faciobrachial dystonic seizures. Autoantibodies against the extracellular domains of VGKC complex proteins, leucine-rich glioma-inactivated 1 (LGI1), and contactin-associated protein-2 (Caspr2), occur in patients with IS, MoS, and LE. However, routine testing has detected VGKC complex antibodies without LGI1 or Caspr2 reactivities (double-negative) in patients with other diseases, such as Creutzfeldt-Jakob disease and amyotrophic lateral sclerosis. Furthermore, double-negative VGKC complex antibodies are often directed against cytosolic epitopes of Kv1 subunits. Therefore, these antibodies should no longer be classified as neuronal-surface antibodies and lacking pathogenic potential. Novel information has been generated regarding autoantibody disruption of the physiological functions of target proteins. LGI1 antibodies neutralize the interaction between LGI1 and ADAM22, thereby reducing the synaptic AMPA receptors. It may be that the main action is on inhibitory neurons, explaining why the loss of AMPA receptors causes amnesia, neuronal excitability and seizures.
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PMID:[Current Perspective on Voltage-gated Potassium Channel Complex Antibody Associated Diseases]. 2963 80

Morvan syndrome (MoS) is typically characterized by neuromyotonia, sleep dysfunction, dysautonomia, and cognitive dysfunction. However, MoS patients with mild peripheral nerve hyperexcitability (PNH) or encephalopathy features have been described. A 46-year-old woman presented with a 2-month history of constipation, hyperhidrosis, and insomnia. Neurologic examination revealed muscle twitching and needle electromyography showed myokymic discharges in all limbs. No clinical or electrophysiological features of neuromyotonia were present. Although the patient denied any cognitive symptoms, neuropsychological assessment revealed executive dysfunction, while other cognitive domains were preserved. Cranial and spinal MRIs were unrevealing and tumor investigation proved negative. Polysomnography examination revealed total insomnia, which was partially reversed upon immune-modulatory therapy. Investigation of a broad panel of antibodies revealed serum leucine-rich glioma inactivated protein 1 and contactin-associated protein 2 antibodies. The features of this case indicate that the presentation of PNH syndromes may show significant variability and that MoS patients may not necessarily exhibit full-scale PNH and encephalopathy symptoms.
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PMID:Insomnia and Dysautonomia with Contactin-Associated Protein 2 and Leucine-Rich Glioma Inactivated Protein 1 Antibodies: A "Forme Fruste" of Morvan Syndrome? 3154 89

Research in the last few years has indicated that most voltage-gated potassium channel- (VGKC-) complex antibodies without leucine-rich glioma-inactivated protein 1 or contactin-associated protein-like 2 antibody specificity lack pathogenic potential and are not clear markers for autoimmune inflammation. Here we report on a patient with double-negative VGKC who developed severe peripheral nerve hyperexcitability, central nervous system symptoms with agitation and insomnia, dysautonomia, and systemic symptoms with weight loss, itch, and skin lesions. The disease started acutely one month after an episode of enteroviral pericarditis and responded well to immunotherapy. The patient is presumed to have developed a postinfectious immunotherapy-responsive autoimmune disease. In the setting of anti-VGKC positivity, it seems likely that anti-VGKC contributed to the pathogenesis of the patient's symptoms of nerve hyperexcitability and that the disease was caused by an acquired autoimmune effect on the neuronal kinetics of VGKC. It is still unknown whether or not there are unidentified extracellular molecular targets within the VGKC-complex, i.e., a novel surface antigen and a pathogenic antibody that can cause affected individuals to develop a peripheral nerve hyperexcitability syndrome. This case highlights the fact that less well-characterized autoimmune central and peripheral nervous system syndromes may have infectious triggers.
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PMID:A Patient with Double-Negative VGKC, Peripheral Nerve Hyperexcitability, and Central Nervous System Symptoms: A Postinfectious Autoimmune Disease. 3312 94