Quantal squander is a rare neuromuscular disorder of continuous muscle fiber activity caused by the hyperexcitability of peripheral neurons. The disease is also known as Isaac syndrome, neuromyotonia, and Isaac-Mertens syndrome. It is most prevalent in the age group of 40 to 60. The characteristic clinical manifestations include muscle twitching at rest, stiffness, cramps, and myokymia. It is either genetic in origin or acquired. Recently, its association with autoimmune disorders has been frequently reported.
There is no standard treatment consensus for Isaac's disease. Commonly interventions depend on symptoms and severity. The common treatment options are:
1. Anticonvulsants such as gabapentin, sodium valproate, phenytoin, carbamazapine, lamotrigine, and acetazolamide. Most anticonvulsants have adverse effects on fetus in patients during pregnancy.
2. When a patient does not respond to anticonvulsants, prednisolone is an alternative in mild cases. 3. The following options may be necessary for severe cases.
- Plasma exchange
- Immunosuppressive agents such as azathioprine and methotrexate
- Immunoglobulin therapy refers to the infusion of immunoglobulins against causative antibodies from a donor.
4. Few reports show the varying effect of anesthetic management on patients. Lumbar epidural anesthesia with 2% carbocaine has effectively reduced myokymic discharges.
Pseudomyotonia (delayed relaxation followed by contraction),Muscle fasciculation,Myokymia (continuous slow contractions in small muscles),Muscle cramps, and stiffness,Patients may also present muscle weakness, distal sensory impairment, hyperhidrosis (increased sweating), and weight loss
Peripheral nerve hyperexcitability
Anticonvulsants such as gabapentin,Sodium valproate,Phenytoin,Carbamazapine,Lamotrigine,Acetazolamide,Corticosteroids such as prednisolone,Immunosuppressive agents such as methotrexate and azathioprine