|
In Principles of Neurology (Adams, Victor, and Ropper, 1997), there are numerous gems of insight and a propensity for embracing the evolution of knowledge. The authors have had a unique opportunity to view the progress of research and the ever-changing science of medicine from the perspective of active researchers, educators and practitioners in the leading medical centers of the country.
The most recent revision continues the tradion of excellence begun when first published over two decades ago in 1976. This is one of the easiest to read and understand technical references available. I am impressed with the scope of this reference, and the authors' ability to express relationships in a dynamic and accessible manner. I recommend this text to anyone interested in the general subject of neurology.
Principles of Neurology, Sixth Edition, 1997
Raymond D. Adams, Maurice Victor, and Allan H. Roper
McGraw-Hill, Health Professions Division, New York
ISBN: 0-07-067439-6
In chapter 54, The hereditary Myotonias and Periodic Paralyses (The Channelopathies), the authors describe what they call a new development in the classification of muscle diseases. This refers to the grouping of hereditary myotonias with the periodic paralyses.
The following quote has a bearing on the goals and general philosophy of the Periodic Paralysis Association.
"In the medical literature, until quite recently, the myotonias stood alone or were thought to be related in some undefined way to the muscular dystrophies. In a similar vein, the periodic paralyses (better called episodic paralyses) have usually been considered with other types of metabolic myopathy. Recent molecular genetic studies, notably those of Rudel, Lehmann-Horn, and Ricker and their associates, have identified the fundamental defects in the myotonias and episodic paralyses and clarified their relationships, and several new forms of nondystrophic myotonia have been defined. It is now known that all these diseases are caused by mutations in genes that code for chloride, sodium, or calcium channels in muscle fiber membranes and all are now referred to as ion channel diseases, or, colloquially, as "channelopathies."
This chapter, beginning on page 1476, provides a careful delineation of the variables associated with these often confusing and misunderstood disorders. An excellent example is the explanation of Myotonia Congenita (Thomsen Disease) as having a "nonprogressive course," and being "set apart from myotonic dystrophy, which has a different genetic basis and is characterized by a progressive degeneration of muscle fibers." A clarification of the differences between Paramyotonia Congenita (Von Eulenberg), and Hyperkalemic Periodic Paralysis is also offered, including,
"In patients with paramyotonia--but not in those with hyperkalemic periodic paralysis--Subramony and colleagues have observed a diminution of the compound muscle action potential in response to the cooling of muscle, settling the argument as to whether the two syndromes (hyperkalemic paralysis and paramyotonia) are the same or different."
|
