$Unique_ID{BRK03901} $Pretitle{} $Title{Kernicterus} $Subject{Kernicterus Bilirubin Encephalopathy Posticteric Encephalopathy Nuclear Jaundice } $Volume{} $Log{} Copyright (C) 1986, 1990 National Organization for Rare Disorders, Inc. 233: Kernicterus ** IMPORTANT ** It is possible the main title of the article (Kernicterus) is not the name you expected. Please check the SYNONYMS listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Bilirubin Encephalopathy Posticteric Encephalopathy Nuclear Jaundice 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. Kernicterus is a condition characterized by an excess of bilirubin in the blood in infancy. The bilirubin is deposited in the basal ganglia of the brain and in the brainstem nuclei. Symptoms Early symptoms of Kernicterus in full term infants may include lethargy, poor feeding and vomiting, a spasm with head and heels bent backward and the body bowed forward (opisthotonus), upward deviation of the eyes, convulsions and muscular rigidity. Later in childhood, survivors may manifest the typical late triad of cerebral palsy marked by ceaseless jerky movements and slow sinuous writhing movements (choreoathetosis), sensorineural hearing loss, and loss of upward gaze. However, only minor problems characterized by perceptual-motor handicaps and learning disorders in school may be present in mild cases. Causes Historically, severe hemolytic jaundice of the newborn was the main cause of Kernicterus. Erythroblastosis Fetalis, another cause of jaundice in infancy, is a hemolytic anemia of the fetus or newborn. It is caused by transmission through the placenta of maternal antibody, which is usually evoked by maternal and fetal blood group incompatibility. Since new improved methods of treating jaundice have evolved, the disorder tends to develop only in premature or sick, very low birthweight infants with unconjugated hyperbilirubinemia, particularly in the presence of certain predisposing factors. These include: 1. low blood oxygen (hypoxemia) 2. acidosis (acidity of the blood) 3. infections 4. low albumin in the blood (hypoalbuminemia) 5. low body temperature (hypothermia). Hyperbilirubinemia is an excess of bilirubin (the breakdown product of hemoglobin and other blood pigments) in the blood. Excess bilirubin causes jaundice which is characterized by a yellow color of the skin (which occurs shortly after birth in this disorder). Related Disorders Jaundice, the yellow skin color which indicates an increased amount of bilirubin in the blood, can have many causes including liver diseases and hemolytic anemias. (For more information on these disorders, choose "liver" and "hemolytic" as your search terms in the Rare Disease Database, and see the related articles in the Prevalent Health Conditions/Concerns area of NORD Services (rdb-4)). Affected Population Kernicterus can affect newborn infants of both sexes. Therapies: Standard Treatment of Kernicterus consists of early, frequent feedings of all newborns to reduce the incidence and severity of too much bilirubin (a product of blood-breakdown) in the blood. These feedings increase the mobility of the bowels and frequency of stools, thereby minimizing the effects of the circulation of bilirubin in the liver and intestines. Phototherapy is used to treatment hyperbilirubinemia. Exposing newborns with this disorder, particularly premature infants, to visible light in the blue range, is most effective for photo-oxidizing bilirubin. Phototherapy causes dermal photoisomerization of bilirubin, changing it to forms that the liver can excrete more readily without glucuronidation. A Plexiglass shield should be placed between the phototherapy lights and the infant to screen out ultraviolet radiation that may be harmful, and the infant should be blindfolded to prevent eye damage from the light. Care must be taken to avoid nasal obstruction by the blindfold. The light should be turned off and the blindfold removed during feedings. Since bilirubin in the collection tubes may photo-oxidize rapidly, the light should also be off when blood is taken for bilirubin determinations. Although data regarding the effects of phototherapy on distribution of bilirubin within the infant's body and long-term effects on mental development of treated infants are not yet available, this form of therapy has gained widespread use. Phototherapy must never be started before the causes of the hyperbilirubinemia have been fully evaluated. Traditionally, dangerous levels of bilirubin are treated by exchange blood transfusion via an umbilical vein catheter in order to prevent Kernicterus. This procedure is safe when done by experienced personnel, especially when it is done on otherwise healthy full-term newborns. Therapies: Investigational The Food and Drug Administration (FDA) has designated Zixoryn (flumecinol) as an orphan drug which can be used for investigational therapy of hyperbilirubinemia. Zixoryn can be used to treat newborn infants with hyperbilirubinemia who are unresponsive to phototherapy. This disease entry is based upon medical information available through January 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 Kernicterus, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 American Liver Foundation 998 Pompton Avenue Cedar Grove, NJ 07201 (201) 857-2626 (800) 223-0179 The United Liver Foundation 11646 West Pico Blvd. Los Angeles, CA 90064 (213) 445-4204 or 445-4200 Children's Liver Foundation 14245 Ventura Blvd. Sherman Oaks, CA 91423 (818) 906-3021 NIH/National Institute of Child Health and Human Development 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5133 For information on genetics and genetic counseling referrals, please contact: 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 THE MERCK MANUAL 15th ed: R. Berkow, et al: eds; Merck, Sharp & Dohme Research Laboratories, 1987. Pp. 1767, 1854, 1883. CECIL TEXTBOOK OF MEDICINE, 18th ed.: James B. Wyngaarden, and Lloyd H. Smith, Jr., Eds.: W.B. Saunders Co., 1988. Pp. 812, 1076.