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Myelodysplastic Syndromes

National Organization for Rare Disorders, Inc.


It is possible that the main title of the report Myelodysplastic Syndromes is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • myelodysplasia
  • pre-leukemia
  • refractory anemia
  • MDS

Disorder Subdivisions

  • None

General Discussion

Myelodysplastic syndromes (MDS) are a rare group of blood disorders that occur as a result of disordered development of blood cells within the bone marrow. The three main types of blood elements (i.e., red blood cells, white blood cells and platelets) are affected. Red blood cells deliver oxygen to the body and remove carbon dioxide, white blood cells help fight infections, and platelets assist in clotting to stop blood loss. In MDS dysfunctional blood cells fail to develop normally and enter the bloodstream. As a result, individuals with MDS have abnormally low blood cell levels (low blood counts). General symptoms associated with MDS include fatigue, dizziness, weakness, bruising and bleeding, frequent infections, and headaches. In some cases, MDS may progress to life-threatening failure of the bone marrow or develop into an acute leukemia. The exact cause of MDS is unknown. There are no clear risk factors but genetics and the environment may play a part. Myelodysplastic syndromes were first noted in the medical literature in 1930s where they were described as pre-leukemic conditions. Myelodysplastic syndromes were not regarded as separate, distinct disorders until 1976. In the past, these disorders have also been known by a variety of names including refractory anemia, oligoblastic anemia, myelodysplastic anemia, pre-leukemia, and smoldering leukemia.


Aplastic Anemia & MDS International Foundation, Inc.

100 Park Avenue, Suite 108

Rockville, MD 20850


Tel: (301)279-7202

Fax: (301)279-7205

Tel: (800)747-2820



Leukemia & Lymphoma Society

1311 Mamaroneck Avenue

Suite 310

White Plains, NY 10605

Tel: (914)949-5213

Fax: (914)949-6691

Tel: (800)955-4572



American Cancer Society, Inc.

250 Williams NW St

Ste 6000

Atlanta, GA 30303


Tel: (404)320-3333

Tel: (800)227-2345

TDD: (866)228-4327


NIH/National Heart, Lung and Blood Institute

P.O. Box 30105

Bethesda, MD 20892-0105

Tel: (301)592-8573

Fax: (301)251-1223



National Cancer Institute

6116 Executive Blvd Suite 300

Bethesda, MD 20892-8322


Tel: (301)435-3848

Tel: (800)422-6237

TDD: (800)332-8615



World Health Organization (WHO)

Avenue Appia 20

Geneva 27, 1211


Tel: 41227912111

Fax: 41227913111


National Bone Marrow Transplant Link

20411 W. 12 Mile Rd

Suite 108

Southfield, MI 48076

Tel: (248)358-1886

Fax: (248)358-1889

Tel: (800)546-5268



Aplastic Anemia & Myelodysplasia Association of Canada

11181 Yonge Street Suite 321

Richmond Hill

Ontario, L4S 1L2


Tel: 9057800698

Fax: 9057801648

Tel: 8888400039



National Marrow Donor Program

3001 Broadway St. NE

Suite 100

Minneapolis, MN 55413-1753


Tel: (612)627-5800

Fax: (612)627-8125

Tel: (800)627-7692



Rare Cancer Alliance

1649 North Pacana Way

Green Valley, AZ 85614



Genetic and Rare Diseases (GARD) Information Center

PO Box 8126

Gaithersburg, MD 20898-8126

Tel: (301)251-4925

Fax: (301)251-4911

Tel: (888)205-2311

TDD: (888)205-3223


Patient Registries at Slone: Myeloma & MDS

Slone Epidemiology Center

1010 Commonwealth Avenue

Boston, MA 02215

Fax: (617)738-5119

Tel: (800)231-3769



Friends of Cancer Research

1800 M Street NW

Suite 1050 South

Washington, DC 22202

Tel: (202)944-6700




American Society of Clinical Oncology

2318 Mill Road Suite 800

Alexandria, VA 22314

Tel: (571)483-1780

Fax: (571)366-9537

Tel: (888)651-3038



Myeloproliferative Disease Support and Daily Email Digest

2011 Flagler Ave.

Key West, FL 33040


Tel: (305)295-4444



For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. 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.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated:  3/15/2012

Copyright  2004, 2005, 2006, 2012 National Organization for Rare Disorders, Inc.

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