Pseudomyotonia Syndrome of Isaacs, also known as Isaacs' Syndrome or Continuous Muscle Activity Syndrome, is a rare neurological disorder characterized by continuous muscle contraction and stiffness. It is named after the British neurologist Arnold Isaacs, who first described the syndrome in 1961.
Individuals affected by Pseudomyotonia Syndrome of Isaacs experience involuntary and constant muscle twitching or contractions, commonly referred to as myokymia. These muscle contractions can be observed in various regions of the body, including the face, limbs, and trunk. As a result, affected individuals may present with muscle stiffness, difficulty relaxing the muscles, and a prominent rippling or "bag of worms" appearance under the skin.
The root cause of Pseudomyotonia Syndrome of Isaacs is not fully understood, but it is believed to involve abnormalities in the communication between nerves and muscles. In some cases, it can be associated with other underlying conditions, such as autoimmune disorders, nerve damage, or certain cancers. The onset of symptoms generally begins in adulthood, but there have been reported cases in children as well.
Diagnosis of Pseudomyotonia Syndrome of Isaacs is often challenging, as the condition is quite rare and its symptoms can mimic other neuromuscular disorders. However, electromyography (EMG) tests, which record and assess electrical activity in the muscles, can aid in confirming the diagnosis. Additionally, ruling out other potential causes through thorough medical history, physical examination, and laboratory investigations is important.
Management of Pseudomyotonia Syndrome of Isaacs focuses on alleviating symptoms and improving quality of life. Antiepileptic medications, such as phenytoin or carbamazepine, are commonly prescribed to control the abnormal muscle activity.
