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$Unique_ID{BRK03467}
$Pretitle{}
$Title{Anemia, Sideroblastic}
$Subject{Anemia Sideroblastic Idiopathic Refractory Sideroblastic Anemia Iron
Overload Anemia Sideroblastosis Thalassemia Minor Thalassemia Major Cooley's
Anemia Idiopathic Hemochromatosis National March}
$Volume{}
$Log{}

Copyright (C) 1987, 1990 National Organization for Rare Disorders, Inc.

351:
Anemia, Sideroblastic

** IMPORTANT **
It is possible the main title of the article (Sideroblastic Anemia) is
not the name you expected.  Please check the SYNONYMS listing to find the
alternate names, disorder subdivisions, and related disorders covered by this
article.

Synonyms

     Idiopathic Refractory Sideroblastic Anemia
     Iron Overload Anemia
     Sideroblastosis

Information on the following diseases can be found in the Related
Disorders section of this report:

     Thalassemia Minor
     Thalassemia Major, also known as Cooley's Anemia
     Idiopathic Hemochromatosis

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.


Sideroblastic Anemias are a group of blood disorders characterized by an
impaired ability of the bone marrow to produce normal red blood cells.  The
iron inside red blood cells is inadequately used to make hemoglobin, despite
adequate or increased amounts of iron.  Abnormal red blood cells called
sideroblasts are found in the blood of people with these types of anemia.

Symptoms

Sideroblastic Anemias are characterized by general weakness, fatigue and
difficulty breathing.  When making a physical effort, persons with this
disorder may feel angina-like chest pains.

More common forms of anemia are caused by low levels of iron in the
blood.  In people with Sideroblastic Anemias, an abnormally high level of
iron and iron-containing substances is found in the blood serum.  The mucous
membranes and the skin of hands and arms of persons with Sideroblastic
Anemias may look pale, often lemon-yellow colored.  Rarely, a brownish red
discoloration caused by bleeding under the skin may occur.

Enlargement of the spleen or liver are other symptoms of these disorders.
Acute leukemia may develop in about 10% of cases as a complication of
advanced Sideroblastic Anemias.

Causes

The exact cause of the Sideroblastic Anemias is unknown.  The disorder may be
due to a failure of the bone marrow to produce normal red blood cells, or to
the inability of the body to utilize appropriately the iron available in the
red blood cells for the manufacture of hemoglobin.

Congenital forms of Sideroblastic Anemia may be sex-linked or autosomal
recessive hereditary disorders.

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.

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 have only 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.

In dominant disorders, a single copy of the disease gene (received from
either the mother or father) will be expressed "dominating" the normal gene
and resulting in appearance of the disease.  The risk of transmitting the
disorder from affected parent to offspring is 50% for each pregnancy
regardless of the sex of the resulting child.)

Acquired forms of Sideroblastic Anemia may be caused by excessive alcohol
consumption, or as a side effect of drugs such as anti-tuberculosis agents,
or the antibiotic drug chloramphenicol.  The anemia may also occur as a
symptom of various other disorders such as granulomatous diseases, tumors, or
rheumatoid arthritis.

Affected Population

Sideroblastic Anemias are very rare disorders.  They are more commonly found
in older persons.

Related Disorders

There are many types of anemia.  They are characterized by decreased red
blood cell and/or hemoglobin content in the blood.  Anemia decreases the
ability to absorb oxygen from the lungs.  A person with severe anemia usually
suffers from weakness, dizziness, headache, ringing in the ears (tinnitus),
spots before the eyes, fatigue, drowsiness, irritability, or even bizarre
behavior.  Absence of menstrual flow in women, loss of sexual drive,
gastrointestinal complaints, or sometimes jaundice or an enlarged spleen may
also be found in some forms of anemia.  Finally, congestive heart failure may
occur in severe cases.

Thalassemia Minor and Major are two hereditary anemias.  Thalassemia
Minor is the milder form of the two.  Thalassemia Major (Cooley's Anemia)
belongs to a group of chronic, familial hemolytic anemias found in persons
with heritage from the Mediterranean basin.  It is characterized by a marked
increase in F hemoglobin and decreased synthesis of the beta polypeptide
chains in the hemoglobin molecule.  Symptoms include a decrease in the number
of red blood cells, a generalized weakness, a vague feeling of malaise,
indigestion and palpitations.

Idiopathic Hemochromatosis is a hereditary disorder of iron metabolism
characterized by excess deposits of iron in the tissues, especially in the
liver, pancreas, and heart, and by bronze-colored pigmentation of the skin.
Cirrhosis of the liver, diabetes mellitus, and associated bone and joint
changes may also occur.

For more information on the above disorders, choose "Thalassemia" and
"Hemochromatosis" as your search terms in the Rare Disease Database.

Therapies:  Standard

To remove excess iron from the body of persons with Sideroblastic Anemia, the
drug desferrioxamine (D.F.) is infused under the skin (subcutaneously) or
injected into a muscle (intramuscular), often with good results.  A
combination of desferrioxamine with ascorbate has been even more effective in
removing excess iron from the body in many cases.

Some forms of Sideroblastic Anemia may respond well to treatment with
pyridoxine, while other types do not respond at all.

Therapies:  Investigational

This disease entry is based upon medical information available through
February 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 Sideroblastic Anemia, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     NIH/National Heart, Lung and Blood Institute
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

     Leukemia Society of America
     733 Third Avenue
     New York, NY  10017
     [phone]

For information on genetics and genetic counseling referrals, please
contact:

     March of Dimes Birth Defects Foundation
     1275 Mamaroneck Avenue
     White Plains, NY  10605
     [phone]

     Alliance of Genetic Support Groups
     35 Wisconsin Circle, Suite 440
     Chevy Chase, MD  20815
     (800) 336-GENE
     [phone]

References

EFFECT OF DOSE, TIME, AND ASCORBATE ON IRON EXCRETION AFTER SUBCUTANEOUS
DESFERRIOXAMINE:  M. A. Hussein et. al.; Lancet (May 7, 1977:  issue 1,8019).
Pp. 977-979.

IDIOPATHIC REFRACTORY SIDEROBLASTIC ANEMIA, INCIDENCE AND RISK FACTORS
FOR LEUKEMIA TRANSFORMATION:  D. S. Chang et al.; Cancer (August 1979:  issue
44,2).  Pp. 724-731.