What is VGKC blood test?
Detection of antibodies to voltage gated potassium channels (VGKC) Typical Presentation: Acute or subacute onset symptoms of limbic encephalitis including confusion/dementia, depression/anxiety and/or seizures or hallucinations, peripheral nerve hyperexcitability, acquired neuromyotonia, autonomic dysfunction.
What does VGKC stand for?
Background Voltage-gated potassium channel (VGKC)-complex antibodies can be associated with a range of immunotherapy-responsive clinical presentations including limbic encephalitis, Morvan’s syndrome and acquired neuromyotonia.
What is VGKC antibody syndrome?
Background: VGKC encephalitis is a recently recognized autoimmune condition with antibodies against components of the VGKC protein complex. Clinical presentation can vary, but patients typically present with limbic encephalitis involving cognitive impairment, seizures and psychiatric symptoms.
What are voltage gated potassium channel antibodies?
Voltage-gated potassium channel antibody disorders include limbic encephalitis, faciobrachial dystonic seizures, and peripheral nerve hyperexcitability disorders that may occur following immunotherapy and/or plasmapheresis.
What is the role of voltage-gated potassium channels?
Voltage-gated potassium ion channels (Kv) play an important role in a variety of cellular processes, including the functioning of excitable cells, regulation of apoptosis, cell growth and differentiation, the release of neurotransmitters and hormones, maintenance of cardiac activity, etc.
How common is Morvan syndrome?
Epidemiology. There are only about 14 reported cases of Morvan’s syndrome in the English literature. With only a limited number of reported cases, the complete spectrum of the central nervous system (CNS) symptomatology has not been well established. The natural history of Morvan’s is highly variable.
What is the difference between voltage-gated sodium and potassium channels?
Voltage-gated sodium channels have two gates (gate m and gate h), while the potassium channel only has one (gate n). Gate m (the activation gate) is normally closed, and opens when the cell starts to get more positive.
What is the difference between a voltage-gated ion channel and a ligand-gated ion channel How are each of these kinds of channels important for the function of a neuron?
Ligand-gated ion channels open when a chemical ligand such as a neurotransmitter binds to the protein. Voltage channels open and close in response to changes in membrane potential. Mechanically-gated channels open in response to physical deformation of the receptor, as in sensory receptors of touch and pressure.
To assess the clinical and immunologic findings in children with voltage-gated potassium channel (VGKC)-complex antibodies (Abs). Methods:
Do noninflammatory patients have lower VGKC-complex ABS at presentation?
The noninflammatory group had significantly lower VGKC-complex Abs at presentation (105–394 pM, median 125 pM) compared with the inflammatory group (103–2,500 pM, median 169 pM) (p= 0.02, Mann–Whitney test). Bars indicate mean ± SEM.
What is anti VGKC complex encephalitis?
Anti-VGKC-complex encephalitis. Anti-VGKC-complex encephalitis are caused by antibodies against the voltage gated potassium channel-complex (VGKC-complex) and are implicated in several autoimmune conditions including limbic encephalitis, epilepsy and neuromyotonia (i.e. Isaacs’ Syndrome).
Are VGKC antibodies targeted against the channel itself?
Antibodies directed against VGKC were first reported in neuromyotonia. Further studies led to VGKC antibodies being recognized in Morvan’s syndrome and limbic encephalitis as well. It was for many years erroneously presumed that antibodies detected in a VGKC assay were targeted against the channel itself.