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$Unique_ID{BRK03892}
$Pretitle{}
$Title{Kallmann Syndrome}
$Subject{Kallmann Syndrome Hypogonadism with Anosmia Hypogonadotropic
Hypogonadism and Anosmia Klinefelter Syndrome Noonan Syndrome Turner Syndrome}
$Volume{}
$Log{}
Copyright (C) 1991, 1992 National Organization for Rare Disorders, Inc.
848:
Kallmann Syndrome
** IMPORTANT **
It is possible that the main title of the article (Kallmann Syndrome) is
not the name you expected. Please check the SYNONYM listing to find the
alternate name and disorder subdivisions covered by this article.
Synonyms
Hypogonadism with Anosmia
Hypogonadotropic Hypogonadism and Anosmia
Information on the following diseases can be found in the Related
Disorders section of this report:
Klinefelter Syndrome
Noonan Syndrome
Turner 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.
Kallmann Syndrome is a rare inherited disorder in which the organ that
produces sex cells does not function properly (hypogonadism) and there is a
loss of the sense of smell (anosmia). The impaired production of hormones as
well as sperm and egg cells often causes delayed puberty, growth and
infertility. This disorder affects both males and females , although it is
more common in males.
Symptoms
Kallmann Syndrome consists of a combination of symptoms. The ovaries in
females and testes in males (known as gonadal glands) do not function
properly causing retardation of growth and sexual development. A impaired
sense of smell (anosmia ) also occurs.
Other symptoms of this disorder may include delayed puberty, color
blindness, cleft-lip or palate, hearing loss and abnormal or absent kidney
development (renal agenesis).
In more severe forms of Kallmann Syndrome abnormalities of the skeleton
such as webbing of two or more fingers or toes (syndactyly), a short fourth
finger of the hand, mental retardation, or an absence of symmetry in the
skull and face (craniofacial asymmetry) may occur.
Females with this disorder may have a deficiency in estrogen (a female
sex hormone), pain during sexual intercourse (dyspareunia), a decrease in
bone mass (osteoporosis), and hot flashes resembling those of menopause.
Symptoms of males with Kallmann Syndrome may be an absence of testes
(male reproductive gland), testes that have not descended into the scrotum
(cryptorchidism), a small penis (micropenis) or an absence of external
genitals (sex organs).
A very rare form of Kallmann Syndrome includes partial or total paralysis
of the muscles in the lower half of the body (spastic paraplegia).
Causes
People with Kallmann Syndrome experience abnormal development of the part of
the brain concerned with the sense of smell (the rhinencephalon). This
abnormal development interferes with the communication between part of the
brain (the hypothalamus) and the gland at the base of the brain that
secretes hormones into the blood (the pituitary). The result is an absence
of the hormone that stimulates reproduction in men (LH or luteinize Hormone)
and women (FSH or Follicle-stimulating hormone), which causes abnormal
secondary sex characteristics and infertility.
Kallmann Syndrome can be inherited as an autosomal dominant, autosomal
recessive, or X-linked recessive disorder. The X-linked form is thought to
be caused by a deletion on the short arm of the X chromosome at the location
of the KALIG-1 gene.
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.
Affected Population
Kallmann Syndrome affects males five times more often than females. The
occurrence of this disorder is one in ten thousand males and one in every
fifty thousand females.
Related Disorders
Symptoms of the following disorders can be similar to those of Kallmann
Syndrome. Comparisons may be useful for a differential diagnosis:
Klinefelter Syndrome is a rare disorder that effects males. It is
characterized by the presence of one or more extra X-chromosomes in at least
one tissue. Abnormally decreased functional activity of the sex glands
(gonad) results in retardation of growth and sexual development.
Other symptoms of Klinefelter Syndrome may be abnormally large mammary
glands in the breasts, small testes, lack of sperm, and abnormally small
penis. (For more information on this disorder choose "Klinefelter Syndrome"
as your search term in the Rare Disease Database).
Noonan Syndrome is a rare genetic disorder that can affect both males and
females. This disorder is characterized by a lack of sexual development,
short stature, possible mental retardation, a webbed neck, skeletal and/or
heart defects, and deformity of the elbow. (For more information on this
disorder choose "Noonan" as your search term in the Rare Disease Database).
Turner Syndrome is a rare genetic disorder that affects females. This
disorder is characterized by a lack of sexual development, small stature,
possible mental retardation, a webbed neck, or heart defects. Individuals
with this disorder have female characteristics, but they do not develop
secondary sexual characteristics. (For more information on this disorder
choose "Turner Syndrome" as your search term in the Rare Disease Database).
Therapies: Standard
Patients with Kallmann Syndrome may be successfully treated with luteinizing
hormone-releasing hormone (LHRH) to stimulate secondary sex characteristics
and sexual function.
Fertility in both sexes may be obtained with gonadotropin-releasing
hormone (GNRH) therapy and in some cases a combination of GNRH and
spermatogenesis (used to induce the formation of sperm in males).
The production of sex cells may be achieved with repeated injections of
human clorionic gonadotropin (hCG) in males, and human menopausal
gonadotropin (hMG) in females.
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 July
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 Kallmann Syndrome, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
Forward Face
560 First Ave.
New York, NY 10016
(212) 263-5205
(800) 422-FACE
NIH/National Institute of Child Health and Human Development
9000 Rockville Pike
Bethesda, MD 20892
301-496-5751
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. 546, 1283, 1660.
INTERNAL MEDICINE, 2nd Ed.: Jay H. Stein, Editor-In-Chief; Little, Brown
and Co., 1987. Pp. 1985-6.
CECIL TEXTBOOK OF MEDICINE, 19th Ed.: James B. Wyngaarden, and Lloyd H.
Smith, Jr., Editors; W.B. Saunders Co., 1990. Pp. 1416-17.
BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief;
Blackwell Scientific Publications, 1990. Pp. 1000.
PRINCIPLES OF NEUROLOGY, 4th Ed.; Raymond D. Adams, M.D. and Maurice
Victor, M.D., Editors; McGraw-Hill Information Services Company, 1989. Pp.
185.
OPHTHALMIC MIDLINE DYSGENESIS IN KALLMANN SYNDROME: M.J. Jaffe, et al.;
Ophthalmic Paediatr Genet (November 1987, issue 8(3)). Pp. 171-4.