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.