$Unique_ID{BRK04084} $Pretitle{} $Title{Paramyotonia Congenita} $Subject{Paramyotonia Congenita Eulenburg Disease Myotonia Congenita Intermittens Paralysis Periodica Paramyotonica Paramyotonia Congenita of Von Eulenburg Von Eulenburg Paramyotonia Congenita Hyperkalemic Periodic Paralysis Myotonic Dystrophy Thomsen Disease Hyperkalemic Periodic Paralysis} $Volume{} $Log{} Copyright (C) 1992 National Organization for Rare Disorders, Inc. 907: Paramyotonia Congenita ** IMPORTANT ** It is possible that the main title of the article (Paramyotonia Congenita) is not the name you expected. Please check the SYNONYMS listing to find the alternate name and disorder subdivisions covered by this article. Synonyms Eulenburg Disease Myotonia Congenita Intermittens Paralysis Periodica Paramyotonica Paramyotonia Congenita of Von Eulenburg Von Eulenburg Paramyotonia Congenita Information on the following diseases can be found in the Related Disorders section of this report: Hyperkalemic Periodic Paralysis Myotonic Dystrophy Thomsen Disease Hyperkalemic Periodic Paralysis General Discussion ** REMINDER ** The Information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Paramyotonia Congenita is a rare muscular disorder inherited as an autosomal dominant trait. This nonprogressive disorder is characterized by a condition in which the muscles do not relax after contracting (myotonia). Symptoms can be triggered by exposure to the cold. There are also intermittent periods of a type of paralysis in which there is no muscle tone (flaccid paresis). This condition does not necessarily coincide with exposure to cold temperatures or myotonia. There is no wasting (atrophy) or increase in bulk (hypertrophy) of muscles with this disorder. Symptoms Patients with Paramyotonia Congenita have a condition in which the muscles do not relax after contracting (myotonia). This condition may become worse with exposure to the cold. The muscles of the face, tongue and hands are most often affected. Repeated contractions of the muscles can aggravate the myotonia (paradoxical myotonia). Some patients with Paramyotonia Congenita may experience a form of paralysis in which muscle tone is lacking (flaccid paresis). These attacks may be accompanied by increased levels of potassium in the blood in some cases but not in others. Paramyotonia Congenita is usually apparent during infancy and is not progressive. Patients with this disorder do not have wasting of muscles (atrophy) or an increase of muscle bulk (hypertrophy). Causes Paramyotonia Congenita is inherited as an autosomal dominant trait. Human traits, including the classic genetic diseases, are the product of the interaction of two genes, one received from the father and one from the mother. In dominant disorders a single copy of the disease gene (received from either the mother or father) will be expressed "dominating" the other normal gene and resulting in the appearance of the disease. The risk of transmitting the disorder from affected parent to offspring is fifty percent for each pregnancy regardless of the sex of the resulting child. Affected Population Paramyotonia Congenita is a very rare disorder that affects males and females in equal numbers. Three large families with multiple generations of affected members have accounted for at least 60 patients with Paramyotonia Congenita. Related Disorders Symptoms of the following disorders can be similar to those of Paramyotonia Congenita. Comparisons may be useful for a differential diagnosis: Hyperkalemic Periodic Paralysis is rare disorder inherited as an autosomal dominant trait and typically detected during infancy. This disorder is characterized by periodic muscle weakness with or without muscles that do not relax after contracting (myotonia). Patients may have attacks once a week or several times a day. Typically the periods of muscle weakness last from one half an hour to an hour. This weakness may be found in the calves or thighs of the legs, lower back, arms, neck and/or eyelids. Periods of muscle weakness usually follow rest after exercise, hunger, infection, exposure to the cold and/or emotional stress. Permanent weakness and wasting of muscles may develop later on. Myotonic Dystrophy is a rare disorder inherited as an autosomal dominant trait. This disorder involves the muscles, vision, and endocrine glands. Myotonic Dystrophy usually begins during young adulthood and is marked initially by an inability to relax muscles after contraction. Loss of muscle strength, mental deficiency, cataracts, reduction of testicular function, and frontal baldness are also symptomatic of this disorder. (For more information on this disorder, choose "Myotonic Dystrophy" as your search term in the Rare Disease Database). Thomsen Disease is a rare disorder inherited as an autosomal dominant trait. This neuromuscular disorder usually begins early in life. Difficulty in initiating movement combined with slowness of muscle relaxation are the primary symptoms. Muscle stiffness of the entire body may also occur. Thomsen Disease is generally a nonprogressive disorder. (For more information on this disorder, choose "Thomsen Disease" as your search term in the Rare Disease Database). Therapies: Standard Some patients with Paramyotonia Congenita may benefit from acetazolamide or thiazide diuretic drugs to reduce the number of paralytic attacks. Treatment with the drug tocainide may help reduce the cold-induced symptoms in some patients. Genetic counseling may be of benefit for patients and their families. Other treatment is symptomatic and supportive. Therapies: Investigational Research on birth defects and their causes is ongoing. The National Institutes of Health (NIH) is sponsoring the Human Genome Project which is aimed at mapping every gene in the human body and learning why they sometimes malfunction. It is hoped that this new knowledge will lead to prevention and treatment of genetic disorders in the future. This disease entry is based upon medical information available through April 1992. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Paramyotonia Congenita, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 The National Arthritis and Musculoskeletal and Skin Diseases Information Clearinghouse Box AMS Bethesda, MD 20892 (301) 495-4484 For Genetic Information and Genetic Counseling Referrals: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References MENDELIAN INHERITANCE IN MAN, 9th Ed.: Victor A. McKusick, Editor: Johns Hopkins University Press, 1990. Pp. 708. CECIL TEXTBOOK OF MEDICINE, 19th Ed.: James B. Wyngaarden, and Lloyd H. Smith, Jr., Editors; W.B. Saunders Co., 1990. Pp. 2284. BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief; Blackwell Scientific Publications, 1990. Pp. 1365-66. PRINCIPLES OF NEUROLOGY, 4th Ed.; Raymond D. Adams, M.D. and Maurice Victor, M.D., Editors; McGraw-Hill Information Services Company, 1989. Pp. 1163. PARAMYOTONIA CONGENITA OR HYPERKALEMIC PERIODIC PARALYSIS? CLINICAL AND ELECTROPHYSIOLOGICAL FEATURES OF EACH ENTITY IN ONE FAMILY: S.M. de Silva, et al.; Muscle Nerve (January, 1990, issue 13(1)). Pp. 21-6.