Electrocardiographic Features in Andersen-Tawil Syndrome
Patients With KCNJ2 Mutations
Characteristic T-U–Wave Patterns Predict the KCNJ2 Genotype
Li Zhang, MD; D. Woodrow Benson, MD, PhD; Martin Tristani-Firouzi, MD; Louis J. Ptacek, MD;
Rabi Tawil, MD; Peter J. Schwartz, MD; Alfred L. George, MD; Minoru Horie, MD, PhD;
Gregor Andelfinger, MD; Gregory L. Snow, PhD; Ying-Hui Fu, PhD;
Michael J. Ackerman, MD, PhD; G. Michael Vincent, MD
Do you suspect that you might have periodic paralysis? The periodic paralyses are a rare group of disorders and there are many conditions which cause an imbalance in serum potassium. So how does the doctor tell the difference between paralysis or weakness caused by an ion channelopathy and any of the other numerous disorders, conditions and reactions which might produce the same symptoms?
In 2009 Professor Dr. Frank Lehmann-Horn of Ulm University, Ulm Germany, gave a presentation on managing hypokalemic periodic paralysis at the Periodic Paralysis Association's conference held in Orlando Florida. This presentation contained so much valuable information in such a compact and understandable format that we asked Dr. Lehmann-Horn for his permission to include it on our website, for the benefit of physicians and patients.
Lehmann-Horn F, Rüdel R, Jurkat-Rott K. Chapter 46: Nondystrophic myotonias and periodic paralyses. In: Myology, edited by AG Engel, C Franzini-Armstrong. McGraw-Hill, New York, 3rd edition, 2004, pp. 1257-1300.
Klingler W, Lehmann-Horn, Jurkat-Rott K. Complications of anesthesia in neuromuscular disorders. Neuromuscular Disord, 15:195-206, 2005.
Patients with Thyrotoxic Hypokalemic Periodic Paralysis typically present at the ER with an acute episode of paralysis involving the muscles of the extremities and limb girdles. The lower limbs are more frequently and severely involved than the upper. Weakness may be asymmetrical. Proximal strength is more severely impaired than distal strength. Respiratory and cardiac arrest are possible. Lie patient in coma position to avoid aspiration.
Hyperkalemic Periodic Paralysis and Paramyotonia Congenita can occur singly or in combination.
While most attacks of Hyperkalemic Periodic Paralysis are brief and do not require emergency intervention, occasionally the serum potassium level will be high enough to cause cardiac distress, or muscle stiffness may interfere with respiration. Attacks of weakness in Paramytonia Congenita are usually mild to moderate in severity, but myotonia of chest, diaphragm and throat muscles can be life-threatening under some circumstances.
The information on this site is based on current medical knowledge but should never at any time be substituted for the advice and care of a properly qualified medical consultant. For medical advice seek the services of a physician.