Thyrotoxic periodic paralysis 2
Type of disease: Rare conditions
Thyrotoxic periodic paralysis (TPP) is a temprorary disease-causing muscle weakness in those with high levels of thyroid hormone in their blood. Thyroid hormone is responsible for regulating the body’s metabolism. TPP occurs when there are extremely high levels of thyroid hormone in the body (hyperthyroidism/thyrotoxicosis). TPP is most commonly seen in Asian men, particularly those of Chinese, Japanese, Vietnamese, Filipino, or Korean heritage.
The primary symptom of TPP is spontaneous muscle weakness/paralysis of the arms and legs. Hypokalemia (low blood-potassium levels) and hyperthyroidism are often seen together and affected individuals might have symptoms of both. Signs of hyperthyroidism include rapid heart rate, increased appetite, anxiety, tremors, and fatigue. TPP attacks may last between 2 to 72 hours, and typically occur at night. Episodes of paralysis may begin with muscle cramps, aches, and stiffness, and may be provoked by excessive carbohydrate consumption or physical activity.
Susceptibility to TPP is genetic, though TPP can also occur sporadically. There are three types of genetic TPP, each caused by a different mutation. Thyrotoxic periodic paralysis 2 (TPP2) specifically is caused by a mutant KCNJ18 gene. Though the mutant TPP2 gene is heritable, the manner by which it is inherited is unclear.
Diagnosis may include blood tests to confirm thyrotoxicosis and hypokalemia. An ECG (electrocardiography) or thyroid tests may also be used to help to diagnose TPP. Treatment involves controlling hyperthyroidism and a strict diet. If an attack impairs breathing/swallowing, the person must be taken to the hospital.
If you or a family member has been diagnosed with TPP, speak with your doctor about the most current treatment options. Support groups may also be available for further resources and information.