children s health issues
Familial Periodic Paralysis
Diagnosis of Familial Periodic Paralysis
Description of an attack Level of potassium in the blood during an attack Exercise test Genetic testing A doctor’s best clue to the diagnosis of familial periodic paralysis is a person’s description of a typical attack. If possible, the doctor draws blood while an attack is in progress to check the level of potassium. If the level of potassium is abnormal, doctors usually do additional tests to be sure the abnormal level is not the result of other causes. In the past, doctors based the diagnosis on provocative testing. In provocative testing, doctors give a person medications by vein (intravenously) that increase or decrease the level of potassium in the blood to see whether they provoke or cause an attack. However, provocative testing may cause serious side effects such as paralysis of the breathing muscles or an abnormal heart rhythm. Thus, provocative testing has been replaced by a safer exercise test. In the exercise test, doctors have the person vigorously exercise a single muscle for 2 to 5 minutes to see if that makes the muscle weak. Doctors record electrical activity from the muscle before and after exercise to see if it was affected. Genetic Screening Before Pregnancy can be done to identify mutations in the affected genes. 