Neuromyotonia
Evidence: Antibody
Names
Neuromyotonia
NMT
Issacs' syndrome
Isaacs-Mertens syndrome
Continuous muscle fiber activity syndrome
Quantal squander syndrome
Description
Neuromyotonia (also known as Issacs' syndrome) is a rare, autoimmune disorder in which hyperactive nerves cause muscles to be over-activated. This hyperactivity results in muscle stiffness, twitching, cramping, increased sweating, and delayed muscle relaxation, especially in the limbs and trunk. These symptoms can occur anytime, even when asleep or under anaesthesia. Weakened reflexes and muscle pain is also common. There is currently no cure, but treatment may manage symptoms.
Patient Groups
Facebook Group: Isaac’s Syndrome
Bloggers
None found.
Prevalence
Unknown, but extremely rare (fewer than 1000 cases in the US).
Typical Age of onset
Typically, neuromyotonia can occur between age 15 to 60 but most patient show symptoms before age 40. It affects males and females but is slightly more common among men.
Source: National Institute of Neurological Disorders and Stroke (NIH)
Symptoms
Muscle twitching (mostly for limb and trunk muscles)
Muscle stiffness
Cramping
Spasms of the hands and feet
Excessive sweating
Delayed muscle relaxation after strong contraction (pseudo myotonia)
Weakened reflexes
Muscle pain
Racing heart
Constipation
Personality change
Insomnia
Psychosis
References
BMJ Journals
Cetin and Vincent (2018)
National Institutes of Health
WebMD
Profile by Rebecca Wang