$Unique_ID{BRK04279} $Pretitle{} $Title{Townes-Brocks Syndrome} $Subject{Townes-Brocks Syndrome Townes Syndrome Anus Imperforate with Hand Foot and Ear Anomalies Deafness Sensorineural with Imperforate Anus and Hypoplastic Thumbs Imperforate Anus VACTERL Association REAR Syndrome Holt-Oram Syndrome } $Volume{} $Log{} Copyright (C) 1990 National Organization for Rare Disorders, Inc. 823: Townes-Brocks Syndrome ** IMPORTANT ** It is possible that the main title of the article (Townes-Brocks Syndrome) is not the name you expected. Please check the SYNONYM listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Townes Syndrome Anus, Imperforate, with Hand, Foot and Ear Anomalies Deafness, Sensorineural, with Imperforate Anus and Hypoplastic Thumbs Information on the following disorders can be found in the Related Disorders section of this report: Imperforate Anus VACTERL Association REAR Syndrome Holt-Oram Syndrome 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. Townes-Brocks Syndrome is a rare genetic disorder present at birth. Symptoms of the disorder and the severity of these symptoms vary from person to person. Major characteristics may include an absence of an anal opening in association with hand, foot and ear abnormalities. Hearing loss or deafness due to lesions or dysfunctions of part of the internal ear or its nerve tracts and centers (sensorineural hearing loss or deafness) is present in some patients. Symptoms Townes-Brocks Syndrome is a rare genetic disorder. Characteristics of this disorder are present at birth and vary from person to person both in type and severity. ABNORMALITIES OF THE FACE AND EARS One side of the face may be smaller than normal (hemifacial microsomia) in individuals with Townes-Brocks Syndrome. External ears can be abnormally large, poorly-formed, or abnormally small (microtia, hypoplastic ears). There may be excess tags of flesh in front of the ears (preauricular protuberances or tags). Hearing loss or deafness due to lesions or dysfunctions of part of the internal ear or its nerve tracts and centers (sensorineural hearing loss or deafness) is present in some patients. ABNORMALITIES OF THE HANDS AND FEET Thumbs of Townes-Brocks Syndrome patients may be smaller than normal (hypoplastic) or may appear to look more like a finger than a thumb. There may be an extra joint or bone in the thumb (triphalangeal thumb) and/or an extra thumb or finger (hexadactyly). Other hand and foot malformations may occur as well. There may be webbing between two or more fingers or toes (syndactyly). Fusions of bone may be present in the wrist. In the feet, fusion of the long bones (metatarsals) may occur, and/or these bones may be shorter than average. Some bones may be absent. The third toe may be missing or underdeveloped (hypoplastic). The fifth toe, or one or more of the fingers of the hand, may be malformed (clinodactyly). ANAL ABNORMALITIES In most patients with Townes-Brocks Syndrome, there is an absence of an anal opening (imperforate anus). Abnormal passages from hollow organs to the body surface or to another organ (fistulas), such as between the rectum and genitals (rectovaginal fistula or rectoperineal fistula), may be present. In some patients, abnormal placement of the anus can occur, and/or the anus may be constricted or smaller than normal (stenosis). Other abnormalities such as abnormal ridges of the genitals (perineal raphe) can also occur. RENAL ABNORMALITIES Underdeveloped kidneys (renal hypoplasia) or other related abnormalities (urorenal anomalies) can occur. Sometimes urine which is supposed to flow from the kidneys to the bladder flows backward (ureterovesical reflux). OCCASIONAL ABNORMALITIES Other characteristics of Townes-Brocks Syndrome can include indentations in front of the ears (preauricular pit), and/or heart (cardiac) defects. Part of the small intestine may be narrowed or occluded (duodenal atresia). Females may develop cysts in the ovary (cystic ovary). In the male there may be an opening located on the underside of the penis (hypospadias); in the female the urethra may open into the vagina. Causes Townes-Brocks Syndrome 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 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 Townes-Brocks Syndrome is an extremely rare disorder present at birth. It affects males and females in equal numbers. Related Disorders Symptoms of the following disorders can be similar to those of Townes-Brocks Syndrome. Comparisons may be useful for a differential diagnosis: Imperforate Anus is a rare abnormality characterized by the absence or abnormal localization of the anus present at birth. The rectum or the colon may be connected to the vagina or the bladder by a tunnel (fistula). With surgical correction, normal elimination can become possible. Imperforate Anus can occur alone or as a symptom of another disorder. (For more information on this disorder, choose "imperforate anus" as your search term in the Rare Disease Database). VACTERL Association is an acronym for (V)ertebral anomalies, (A)nal atresia (absence of a normal anal opening), congenital (C)ardiac disease, (T)racheo(E)sophageal fistula (abnormal openings or passages between the windpipe and upper digestive tract), (R)enal anomalies, radial dysplasia, and other (L)imb defects. Abnormalities are present at birth. Symptoms occur in various combinations and can be manifestations of several recognized disorders. REAR Syndrome is an acronym for (R)enal anomalies, deformed external (E)ars and perceptive deafness, (A)nal stenosis, and (R)adial dysplasia. Underdeveloped kidneys are the most common renal abnormalities. The external ears are abnormally developed and deafness is present at birth. The anus is constricted or smaller than normal and other anal abnormalities can also occur. Abnormal tissue development is present in the area of the bone in the forearm (radius). (For more information on these disorders, choose "VACTERL" as your search term in the Rare Disease Database). Holt-Oram Syndrome, also known as Atriodigital Dysplasia or Heart-Hand Syndrome, is a genetic disorder comprised of atrial septal defect in association with hand and forearm deformities. (For more information on this disorder, choose "Holt" as your search term in the Rare Disease Database). Therapies: Standard Treatment of Townes-Brocks Syndrome often includes surgery for malformations associated with this syndrome. Genetic counseling may be of benefit for patients and their families. Other treatment is symptomatic and supportive. Therapies: Investigational This disease entry is based upon medical information available through November 1990. 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 Townes-Brocks Syndrome, please contact: National Organization for Rare Disorders P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 NIH/National Institute of Child Health and Human Development 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5133 Hemifacial Microsomia Family Support Network 84 Glennifer Hill Rd. Richboro, PA 18954 (215) 364-3199 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, 8th Ed.: Victor A. McKusick; Johns Hopkins University Press, 1986. Pp. 69. SMITH'S RECOGNIZABLE PATTERNS OF HUMAN MALFORMATION, 4th Ed.: Kenneth Lyons Jones, M.D.; W.B. Saunders Co., 1988. Pp. 218-219. A NEW FAMILY WITH THE TOWNES-BROCKS SYNDROME. M. A. de Vries-Van der Weerd, et al.; Clin Genet (Sep 1988; issue 34 (3)). Pp. 195-200. PHENOTYPIC VARIABILITY IN TOWNES-BROCKS SYNDROME. J. Monteiro de Pina- Neto; Am J Med Genet (May 1984; issue 18 (1)). Pp. 147-152. TOWNES-BROCKS SYNDROME. REPORT OF A CASE AND REVIEW OF THE LITERATURE. F. G. Ferraz, et al.; Ann Genet (1989; issue 32 (2)). Pp. 120-123. TOWNES SYNDROME. A DISTINCT MULTIPLE MALFORMATION SYNDROME RESEMBLING VACTERL ASSOCIATION. J. H. Hersh, et al.; Clin Pediatr (Phila) (Feb 1986; issue 25 (2)). Pp. 100-102.