Extinguishing a “Burning Fire”

Isaacs syndrome is a rThTare acquired neuromuscular disorder characterized by peripheral nerve hyperexcitability. Symptoms involve progressive muscle pain, stiffness, and notable continuous diffuse myokymic muscle-twitching clinically consistent with neuromyotonia. There can be associated weakness, hyporeflexia, numbness, dysesthesias, and hyperhidrosis. Isaacs syndrome generally presents between ages 25–60, more commonly in men. Etiologies include autoimmune, often paraneoplastic, syndromes, typically associated with malignant thymic carcinomas. Therapeutic management involves treating the underlining malignancy, as well as using immune-mediated therapies including corticosteroids, intravenous immunoglobulin, plasma exchange, and rituximab. The long-term prognosis for patients with Isaacs syndrome varies, generally dependent on the underlying cause. While Isaacs syndrome is a chronic condition without a cure, it is generally treatable and not fatal.

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Markov cellular automata models for chronic disease progression

International Journal of Biomathematics ◽

10.1142/s1793524515500850 ◽

2015 ◽

Vol 08 (06) ◽

pp. 1550085 ◽

Cited By ~ 4

Author(s):

Jane Hawkins ◽

Donna Molinek

Keyword(s):

Dynamical System ◽

Human Immunodeficiency Virus ◽

Hepatitis C ◽

Chronic Conditions ◽

Chronic Condition ◽

Physical Significance ◽

Markov Shifts ◽

Immunodeficiency Virus ◽

Long Term Prognosis

We analyze a Markov cellular automaton that models the spread of viruses that often progress to a chronic condition, such as human immunodeficiency virus (HIV) or hepatitis C virus (HCV). We show that the complex dynamical system produces a Markov process at the later stages, whose eigenvectors corresponding to the eigenvalue 1 have physical significance for the long-term prognosis of the virus. Moreover we show that drug treatment leads to chronic conditions that can be modeled by Markov shifts with more optimal eigenvectors.

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Peripheral nerve hyperexcitability syndromes

Reviews in the Neurosciences ◽

10.1515/revneuro-2014-0066 ◽

2015 ◽

Vol 26 (2) ◽

Cited By ~ 7

Author(s):

Cem Ismail Küçükali ◽

Murat Kürtüncü ◽

Halil İbrahim Akçay ◽

Erdem Tüzün ◽

Ali Emre Öge

Keyword(s):

Nervous System ◽

Peripheral Nerve ◽

Immune Modulation ◽

Symptomatic Treatment ◽

Immune Mediated ◽

Morvan’S Syndrome ◽

Peripheral Nerve Hyperexcitability ◽

The Central Nervous System ◽

Electrophysiological Findings ◽

Symptoms And Signs

AbstractPeripheral nerve hyperexcitability (PNH) syndromes can be subclassified as primary and secondary. The main primary PNH syndromes are neuromyotonia, cramp-fasciculation syndrome (CFS), and Morvan’s syndrome, which cause widespread symptoms and signs without the association of an evident peripheral nerve disease. Their major symptoms are muscle twitching and stiffness, which differ only in severity between neuromyotonia and CFS. Cramps, pseudomyotonia, hyperhidrosis, and some other autonomic abnormalities, as well as mild positive sensory phenomena, can be seen in several patients. Symptoms reflecting the involvement of the central nervous system occur in Morvan’s syndrome. Secondary PNH syndromes are generally seen in patients with focal or diffuse diseases affecting the peripheral nervous system. The PNH-related symptoms and signs are generally found incidentally during clinical or electrodiagnostic examinations. The electrophysiological findings that are very useful in the diagnosis of PNH are myokymic and neuromyotonic discharges in needle electromyography along with some additional indicators of increased nerve fiber excitability. Based on clinicopathological and etiological associations, PNH syndromes can also be classified as immune mediated, genetic, and those caused by other miscellaneous factors. There has been an increasing awareness on the role of voltage-gated potassium channel complex autoimmunity in primary PNH pathogenesis. Then again, a long list of toxic compounds and genetic factors has also been implicated in development of PNH. The management of primary PNH syndromes comprises symptomatic treatment with anticonvulsant drugs, immune modulation if necessary, and treatment of possible associated dysimmune and/or malignant conditions.

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Facial myokymia in inherited peripheral nerve hyperexcitability syndrome

Practical Neurology ◽

10.1136/practneurol-2019-002462 ◽

2020 ◽

Vol 20 (3) ◽

pp. 253-255

Author(s):

Clara Gontijo Camelo ◽

André Macedo Serafim Silva ◽

Cristiane Araújo Martins Moreno ◽

Ciro Matsui-Júnior ◽

Carlos Otto Heise ◽

...

Keyword(s):

Peripheral Nerve ◽

Autosomal Dominant ◽

Gene Mutations ◽

Epileptic Encephalopathy ◽

Neonatal Seizures ◽

Muscle Cramps ◽

Immune Mediated ◽

Peripheral Nerve Hyperexcitability ◽

Antiepileptic Medications ◽

Dominant Condition

Peripheral nerve hyperexcitability syndrome comprises a heterogeneous group of diseases, clinically characterised by myokymia, fasciculation, muscle cramps and stiffness. The causes are either immune mediated or non-immune mediated. Non-immune-mediated forms are mostly genetic, relating to two main genes: KCNQ2 and KCNA1. Patients with KCNQ2 gene mutations typically present with epileptic encephalopathy, benign familial neonatal seizures and myokymia, though occasionally with purely peripheral nerve hyperexcitability. We report a woman with marked facial myokymia and distal upper limb contractures whose mother also had subtle facial myokymia; both had the c.G620A (p.R207Q) variant in the KCNQ2 gene. Patients with familial myokymia and peripheral nerve hyperexcitability syndrome should be investigated for KCNQ2 variants. This autosomal dominant condition may respond to antiepileptic medications acting at potassium channels.

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