Is Paramyotonia congenita rare?
Paramyotonia congenita (PMC) is a rare non-progressive genetic disorder that affects the skeletal muscles. The disorder typically begins in infancy or early childhood.
What is the prognosis for patients diagnosed with Paramyotonia congenita?
Most individuals with myotonia congenita lead long, productive lives. Although muscle stiffness may interfere with walking, grasping, chewing, and swallowing, it is usually relieved with exercise. Most individuals with myotonia congenita lead long, productive lives.
How common is Paramyotonia congenita?
Paramyotonia congenita is an uncommon disorder; it is estimated to affect fewer than 1 in 100,000 people.
How is Paramyotonia congenita diagnosis?
Diagnosis. Diagnosis of paramyotonia congenita is made upon evaluation of patient symptoms and case history. Myotonia must increase with exercise or movement and usually must worsen in cold temperatures. Patients that present with permanent weakness are normally not characterized as having PC.
What are the symptoms of paramyotonia congenita in children?
Paramyotonia congenita is an inherited condition that affects muscles used for movement (skeletal muscles), mainly in the face, neck, arms, and hands. Symptoms begin in infancy or early childhood and include episodes of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally and lead to muscle weakness.
When does paramyotonia become more severe during pregnancy?
Some patients believe that they are more susceptible to paramyotonia when they have a cold. Paramyotonia may become more severe during pregnancy, so that the leg muscles stiffen even under warm conditions. Hypothyroidism also causes generalization of paramyotonia and aggravates both muscle stiffness and weakness.
Which is paradoxical myotonia or paramyotonia congenita?
Paramyotonia congenita (PC), is a rare congenital autosomal dominant neuromuscular disorder characterized by “paradoxical” myotonia. This type of myotonia has been termed paradoxical because it becomes worse with exercise whereas classical myotonia, as seen in myotonia congenita, is alleviated by exercise.
Why is muscle stiffness caused by paramyotonia congenita?
However, if paramyotonia congenital, muscle stiffness is brought on by exercise. This is the opposite of the ‘warm up’ effect so is called ‘paradoxical’ or ‘paramyotonia’.