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$Unique_ID{BRK03869}
$Pretitle{}
$Title{Ichthyosis, Harlequin Type}
$Subject{Ichthyosis, Harlequin Type Harlequin Fetus DOC 6 (Harlequin Type)
Disorder of Cornification 6 (Harlequin Type) Ichthyosis Harlequin Type
Ichthyosis Congenita, Harlequin Fetus Type Ichthyosis (Disorders of
Cornification)}
$Volume{}
$Log{}
Copyright (C) 1988, 1989, 1991, 1992, 1993 National Organization for Rare
Disorders, Inc.
546:
Ichthyosis, Harlequin Type
** IMPORTANT **
It is possible the main title of the article (Harlequin Type Ichthyosis)
is not the name you expected. Please check the SYNONYMS listing on the next
page to find alternate names and disorder subdivisions covered by this
article.
Synonyms
Harlequin Fetus
DOC 6 (Harlequin Type)
Disorder of Cornification 6 (Harlequin Type)
Ichthyosis Harlequin Type
Ichthyosis Congenita, Harlequin Fetus Type
Information on the following disorders can be found in the Related
Disorders section of this report:
Ichthyosis (Disorders of Cornification)
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.
Harlequin Type Ichthyosis is a rare genetic skin disorder characterized
by massive, thick skin plates that usually produce distorted facial features
and often deformities in other parts of the body. At birth the chest and
abdomen of patients are usually severely constricted. This makes breathing
and eating difficult. The skin symptoms can be somewhat controlled with
treatment.
Symptoms
At birth, babies with Harlequin Type Ichthyosis have massive, thick scales on
the skin. An abnormally large amount of dead skin cells (squames)
accumulates in the top layer of the skin. The conversion of an abnormally
large number of epidermal cells is thought to be caused by a defect in the
metabolism of the skin cells known as "corneocytes" or of the fat-rich matrix
around these cells. The cells can be thought of as bricks, while the matrix
would be the mortar holding these cells together. The scaly plates formed by
these dead skin cells cause the dermatological symptoms. The chest and
abdomen of these infants are severely constricted at birth. This makes
breathing and eating difficult.
Causes
Harlequin Type Ichthyosis is a hereditary disorder transmitted through
autosomal recessive genes. (Human traits including the classic genetic
diseases, are the product of the interaction of two genes for that condition,
one received from the father and one from the mother. In recessive
disorders, the condition does not appear unless a person inherits the same
defective gene 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 show no 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.)
Affected Population
Harlequin Type Ichthyosis is a rare skin condition that affects infants
before birth. Males and females are affected in equal numbers. It affects
one in 500,000 persons or two per million. Harlequin type Ichthyosis affects
about 500 persons and occurs in seven births annually in the United States.
Related Disorders
Symptoms of the following disorders may be similar to those of Harlequin Type
Ichthyosis. Inversion of an abnormally large number of epidermal cells into
squamous cells is thought to be caused by a defect in the metabolism of the
skin cells known as "corneocytes" or of the fat-rich matrix around these
cells. The cells can be comparumulation of large amounts of dead cells
(squames) in the top layer of the skin.
Ichthyosis Congenita (Collodion Baby; Congenital Ichthyosiform
Erythroderma; Xeroderma; Desquamation of Newborn) is an inherited skin
disorder. It is characterized by generalized, abnormally red, dry and rough
skin, with large, coarse scales. Itchiness (pruritus) usually also develops.
Skin on the palms of the hands and soles of the feet is abnormally thick.
(For more information, choose "Ichthyosis Congenita" as your search term in
the Rare Disease Database.)
X-Linked Ichthyosis is an inherited skin disorder caused by a deficiency
in the enzyme steroid sulfatase. This enzyme deficiency leads to biochemical
alterations in steroid hormone metabolism. Cholesterol sulfate may
accumulate in the blood and skin. (For more information, choose "X-Linked
Ichthyosis " as your search term in the Rare Disease Database.)
Other forms of Ichthyosis include Sjogren-Larsson Syndrome, Netherton
Syndrome, Ichthyosis Hystrix, Lamellar Ichthyosis, Refsum Syndrome, Darier
Disease, Conradi-Hunermann Syndrome, Chanarin-Dorfman Syndrome, Epidermolytic
Hyperkeratosis, etc. (Search under each name for more information on that
disorder in the Rare Disease Database.)
Therapies: Standard
Harlequin Type Ichthyosis can be diagnosed before birth by removing a tiny
skin sample from the fetus and examining this for abnormal cells. This test
is called fetoscopy.
The skin symptoms of Harlequin Type Ichthyosis are treated by applying
skin softening (emollient) ointments, preferably plain petroleum jelly. This
can be especially effective after bathing, while the skin is still moist.
Salicylic acid gel is another particularly effective ointment. The skin
should be covered at night with an airtight, waterproof dressing when this
ointment is used. Lactate lotion can also be an effective treatment for this
disorder.
Other treatment is symptomatic and supportive.
Therapies: Investigational
Drugs derived from Vitamin A (retinoids) such as tretinoin, motretinide, and
etretinate are often effective against the dermatologic symptoms of Harlequin
Type Ichthyosis, but can cause toxic effects on the bones in some cases. A
synthetic derivative of Vitamin A, isotretinoin, when taken by pregnant
women, can cause severe birth defects to the fetus. These Vitamin A
compounds have not yet been approved by the Food and Drug Administration for
treatment of Ichthyosis.
The National Institute of Arthritis, Musculoskeletal and Skin Diseases is
looking for patients with various kinds of Ichthyosis willing to participate
in research aimed at mapping the genes responsible for their disorder.
Interested persons may contact:
Dr. Sherri Bale
National Institute of Arthritis, Musculoskeletal and Skin Diseases
9000 Rockville Pike
Bethesda, MD 20892
(301) 402-2679
The orphan product Monolaurin (Glylorin) is being tested for treatment of
Harlequin Type Ichthyosis. The product is manufactured by:
Cellegy Pharmaceuticals, Inc.
371 Bel Marin Keys, Suite 210
Novato, CA 94949
This disease entry is based upon medical information available through
May 1993. 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 Harlequin Type Ichthyosis, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
Foundation for Ichthyosis and Related Skin Types, Inc. (F.I.R.S.T.)
P.O. Box 20921
Raleigh, NC 27619-0921
(919) 782-5728
(800) 545-3286
The National Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Information Clearinghouse
Box AMS
Bethesda, MD 20892
(301) 495-4484
For genetic information 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
GENETICALLY TRANSMITTED, GENERALIZED DISORDERS OF CORNIFICATION. THE
ICHTHYOSES: M.L. Williams, et al.; Dermatol Clin (January 1987: issue
5(1)). Pp. 155-178.
THERAPEUTIC ACTIVITY OF LACTATE 12% LOTION IN THE TREATMENT OF
ICHTHYOSIS. ACTIVE VERSUS VEHICLE AND ACTIVE VERSUS A PETROLEUM CREAM: M.
Buxman, et al.; Journal Am Acad Dermatol (December 1986: issue 15(6)). Pp.
1253-1258.
THE METABOLIC BASIS OF INHERITED DISEASE, 5th ed.: John B. Stanbury, et
al., eds.; McGraw Hill, 1983. Pp. 1027-1039.
MENDELIAN INHERITANCE IN MAN, 7th ed.: Victor A. McKusick; Johns
Hopkins University Press, 1986. P. 1059.