Myelodysplastic syndromes (MDS) are a group of blood diseases that cause an abnormally low production of blood cells. MDS is more common in older adults and rare in children and may develop before the start of a more serious blood disease, acute myelogenous leukemia.

Symptoms of MDS include a decreased production of red blood cells (anemia) and bleeding caused by a decreased production of platelet cells (thrombocytopenia). Later symptoms include enlargement of the liver (hepatomegaly), enlargement of the spleen (splenomegaly), and swelling of the lymph nodes (lymphadenopathy).

Treatment of MDS depends on the severity of the disease and can include blood transfusions and chemotherapy.