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- $Unique_ID{BRK03680}
- $Pretitle{}
- $Title{Dyskeratosis Congenita}
- $Subject{Dyskeratosis Congenita DKC Dyschromatosis Universalis Hereditaria
- Dyskeratosis Congenita Autosomal Recessive Type Dyskeratosis Congenita
- Scoggins Type Dyskeratosis Congenita Syndrome Zinsser-Cole-Engman Syndrome
- Ectodermal Dysplasias Fanconi's Anemia}
- $Volume{}
- $Log{}
-
- Copyright (C) 1992 National Organization for Rare Disorders, Inc.
-
- 896:
- Dyskeratosis Congenita
-
- ** IMPORTANT **
- It is possible that the main title of the article (Dyskeratosis
- 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
-
- DKC
- Dyschromatosis Universalis Hereditaria
- Dyskeratosis Congenita, Autosomal Recessive Type
- Dyskeratosis Congenita, Scoggins Type
- Dyskeratosis Congenita Syndrome
- Zinsser-Cole-Engman Syndrome
-
- Information on the following diseases can be found in the Related
- Disorders section of this report:
-
- Ectodermal Dysplasias
- Fanconi's Anemia
-
- 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.
-
- Dyskeratosis Congenita is a rare disorder in which three groups of
- symptoms occur: darkening and/or unusual absence of skin color
- (hyper/hypopigmentation); progressive nail dystrophy; and slowly changing
- characteristics of mucous membranes (leukoplakia) in the anus, urethra, lips,
- mouth and/or eye.
-
- Other symptoms found in some patients with this syndrome may be reduction
- in red and white blood cells and platelets (pancytopenia), overgrowth of skin
- on the palms of the hands and soles of the feet, excessive sweating of the
- palms and soles, sparse or absent hair, fragile bones, underdeveloped testes,
- and dental abnormalities. Dyskeratosis Congenita is more prevalent among
- males then females and an X-linked recessive inheritance is the most common
- form although cases of autosomal recessive and autosomal dominant inheritance
- have been recorded. This disorder has also occurred sporadically (no known
- cause) in a significant number of cases.
-
- Symptoms
-
- The main symptoms of Dyskeratosis Congenita are:
-
- 1. Hyper and Hypopigmentation - Hyperpigmentation in Dyskeratosis
- Congenita has a net like pattern of distribution that is brownish-grey in
- color. Hypopigmentation is a lack of skin color that is intermixed. These
- skin discolorations may be present at birth but usually are progressive and
- appear later.
-
- 2. Progressive nail dystrophy may lead to loss of nails on the fingers
- or toes. This is visually not present at birth.
-
- 3. Mucosal leukoplakia - a slowly developing change in normal tissue of
- a mucous membrane. This condition may be found in the mucous membranes of
- the anus, urethra, lips, mouth and/or eyes. This condition should be watched
- closely and the leukoplakic lesions removed before they can become malignant.
-
- The following conditions are often, but not always, present in patients
- with Dyskeratosis Congenita:
-
- 4. Pancytopenia - a reduction in the normal number of red and white
- blood cells and platelets caused by bone marrow failure.
-
- 5. Hyperkeratosis - the overgrowth of skin on the palms of the hands and
- the soles of the feet. This condition often causes a lack of finger and foot
- prints.
-
- 6. Hyperhidrosis - excessive sweating of the palms of the hands and the
- soles of the feet.
-
- 7. Atresia of the lacrimal puncta - absence of the tiny opening in the
- edge of each eyelid that drains the tears. This condition causes chronic
- tearing.
-
- The following conditions are sometimes associated with Dyskeratosis
- Congenita and have been found in some patients with this disorder:
-
- 8. Alopecia - absence of hair from skin areas where it is normally
- present. The hair is often fine and sparse and there may be premature
- graying.
-
- 9. Dental abnormalities - displacement of teeth from a normal position
- in the dental arch. Teeth may also be lost at an early age.
-
- 10. Osteoporosis - a decrease in bone mass. Patients with Dyskeratosis
- Congenita may also have a fragile build and a slow growth pattern.
-
- 11. Testicular atrophy - incomplete or underdeveloped testes. The penis
- may also be underdeveloped.
-
- 12. Thrombocytopenia - an abnormally small number of platelets (the part
- of the blood that helps in clotting) in the circulating blood.
-
- 13. Microcephaly - a small circumference of the head.
-
-
- 14. Mental retardation or reduced intelligence.
-
- 15. Cirrhosis of the liver - a long-term disease of the liver in which
- the liver becomes covered with fiberlike tissue and hardens - also called
- nutmeg-like cirrhosis.
-
- 16. Dysphasia - difficulty in swallowing.
-
- 17. Acrocyanosis - hands and/or feet that are a blue color, cold and
- sweaty. This is caused by spasms of the blood vessels and usually occurs
- when the patient is cold or under stress.
-
- 18. Cataracts - a disease of the eye in which the lens loses it's
- clearness. A grey-white film can be seen in the lens. (For more information
- on this disorder choose "Cataracts" as your search term in the Rare Disease
- Database).
-
- Causes
-
- Most cases of Dyskeratosis Congenita have an X-linked recessive inheritance
- although cases have been reported of autosomal recessive and autosomal
- dominant inheritance. A significant number of cases have also occurred
- sporadically.
-
- 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.
-
- In recessive disorders, the condition does not appear unless a person
- inherits the same defective gene for the same trait from each parent. If one
- receives one normal gene and one gene for the disease, the person will be a
- carrier for the disease, but usually will not show symptoms. The risk of
- transmitting the disease to the children of a couple, both of whom are
- carriers for a recessive disorder, is twenty-five percent. Fifty percent of
- their children will be carriers, but healthy as described above. Twenty-five
- percent of their children will receive both normal genes, one from each
- parent, and will be genetically normal.
-
- X-linked recessive disorders are conditions which are coded on the X
- chromosome. Females have two X chromosomes, but males have one X chromosome
- and one Y chromosome. Therefore, in females, disease traits on the X
- chromosome can be masked by the normal gene on the other X chromosome. Since
- males only have one X chromosome, if they inherit a gene for a disease
- present on the X, it will be expressed. Men with X-linked disorders transmit
- the gene to all their daughters, who are carriers, but never to their sons.
- Women who are carriers of an X-linked disorder have a fifty percent risk of
- transmitting the carrier condition to their daughters, and a fifty percent
- risk of transmitting the disease to their sons.
-
- Dyskeratosis Congenita has been mapped to the Xq27-q28 gene.
-
- Affected Population
-
- Dyskeratosis Congenita affects males most often, with the ratio of affected
- males to females being M10:F1. This disorder is usually detected between the
- ages of five and fifteen although skin and nail abnormalities may be present
- at birth. There have been only 120 cases of Dyskeratosis Congenita reported
- and the disease has occurred in all races.
-
- Related Disorders
-
- Symptoms of the following disorders can be similar to those of Dyskeratosis
- Congenita. Comparisons may be useful for a differential diagnosis:
-
- Ectodermal Dysplasias are a group of hereditary, non-progressive
- syndromes in which the affected tissue derives primarily from the ectodermal
- germ layer. The skin, it's derivatives, and some other organs are involved.
- A predisposition to respiratory infections, due to a somewhat depressed
- immune system and to defective mucous glands in parts of the respiratory
- tract, is the most life threatening characteristic of this group of
- disorders. Symptoms include eczema, poorly functioning sweat glands, sparse
- or absent hair follicles, abnormal hair, disfigured nails, and difficulties
- with the nasal passages and ear canals. Skin is satiny smooth, prone to
- rashes, and slow to heal. (For more information on this disorder choose
- "Ectodermal Dysplasias" as your search term in the Rare Disease Database).
-
- Fanconi's Anemia is a rare form of familial aplastic anemia (a disease of
- the bone marrow) found chiefly in children. It is characterized by bone
- marrow abnormalities, a small circumference of the head, retarded sexual
- development and brown pigmentation of the skin. Complications such as
- pneumonia and meningitis, hemorrhages and leukemia may occur. (For more
- information on this disorder choose "Anemia, Fanconi's" as your search term
- in the Rare Disease Database).
-
- Therapies: Standard
-
- Treatment of Dyskeratosis Congenita is symptomatic and supportive.
- Leukoplakic lesions should be surgically removed to prevent malignancy.
- Dental abnormalities will require dental intervention.
-
- Genetic counseling may be of benefit for patients and their families.
-
- 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
- February 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 Dyskeratosis Congenita, please contact:
-
- National Organization for Rare Disorders
- P.O. Box 8923
- New Fairfield, CT 06812-1783
- (203) 746-6518
-
- National Foundation for Ectodermal Dysplasias
- 219 E. Main St.
- Mascoutah, IL 62258
- (618) 566-2020
-
- NIH/National Institute of Child Health and Human Development (NICHD)
- 9000 Rockville Pike
- Bethesda, MD 20892
- (301) 496-5133
-
- NIH/National Heart, Lung and Blood Institute (NHLBI)
- 9000 Rockville Pike
- Bethesda, MD 20892
- (301) 496-4236
-
- 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. 275, 1154, 1586.
-
- SMITH'S RECOGNIZABLE PATTERNS OF HUMAN MALFORMATION, 4th Ed.: Kenneth L.
- Jones, M.D., Editor; W.B. Saunders Co., 1988. Pp. 474.
-
- BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief;
- Blackwell Scientific Publications, 1990. Pp. 567-68.
-
- DIAGNOSTIC RECOGNITION OF GENETIC DISEASES, William Nyhan, Nadia O
- Sakati, Editors; Lea & Febiger, 1987. Pp. 600, 672.
-
- ENHANCED G2 CHROMATID RADIOSENSITIVITY TO DYSKERATOSIS CONGENITA
- FIBROBLASTS: D.M. DeBauche, et al.; Am J Hum Genet (February, 1990, issue
- 46(2)). Pp. 350-7.
-
- DYSKERATOSIS CONGENITA: REPORT OF A CASE AND REVIEW OF THE LITERATURE:
- G.R. Ogden, et al.; Oral Surg Oral Med Oral Pathol (May 1988, issue 65(5)).
- Pp. 586-91.
-
- ETIOLOGIC HETEROGENEITY IN DYSKERATOSIS CONGENITA: G.S. Pai, et al.; Am
- J Med Genet (January 1989, issue 32(1)). Pp. 63-6.
-
-