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Isaacs Syndrome

(Isaacs' Syndrome; Neuromyotonia)

By

Michael Rubin

, MDCM, New York Presbyterian Hospital-Cornell Medical Center

Last full review/revision Dec 2020
CLICK HERE FOR THE PROFESSONAL VERSION

Isaacs syndrome involves overstimulation of the nerves that stimulate muscle fibers. It causes progressive muscle stiffness, continuous muscle quivering and twitching, and cramping.

  • In people with Isaacs syndrome, muscles, particularly those in the arms and legs, continually quiver and twitch, moving like a bag of worms, and often become progressively stiffer.

  • Doctors diagnose Isaacs syndrome based on symptoms and results of electromyography and nerve conduction studies.

  • The antiseizure drugs carbamazepine or phenytoin can relieve symptoms, and some people benefit from immune globulin or plasma exchange.

Muscles, particularly those in the arms and legs, continually quiver and twitch, moving like a bag of worms. This symptom is called myokymia. Spasms and cramps may intermittently occur in the hands and feet. Muscles often become progressively stiffer and take a long time to relax after they have been contracted. Sweating may be increased.

Treatment of Isaacs Syndrome

  • Carbamazepine or phenytoin (antiseizure drugs)

  • Immune globulin and plasma exchange

People may also benefit from immune globulin (a solution containing many different antibodies collected from a group of donors), given intravenously, or plasma exchange Plateletpheresis (platelet donation) In addition to normal blood donation and transfusion, special procedures are sometimes used. In plateletpheresis, a donor gives only platelets rather than whole blood. Whole blood is drawn from... read more (filtering of toxic substances, including abnormal antibodies, from the blood).

Drugs Mentioned In This Article

Generic Name Select Brand Names
Gammagard S/D
TEGRETOL
DILANTIN
NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSONAL VERSION
CLICK HERE FOR THE PROFESSONAL VERSION
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