An Overview of Myelodysplastic Syndromes

Two months before she retired, Carole realized she would need a part-time job to make ends meet. She felt lucky to find work two days a week in a law office near her home. At the end of her first week on the new job, however, she felt exhausted and short of breath. Lab tests revealed she suffered from a myelodysplastic syndrome.

Overview

A myelodysplastic syndrome is one of a group of disorders caused by dysfunctional or poorly formed blood cells, according to the Mayo Clinic. The abnormal cells are the result of some type of event gone awry in the body's bone marrow.

Every year, between 10,000 and 15,000 patients in the United States receive a diagnosis of myelodysplastic syndrome, according to the National Marrow Donor Program. Four out of every five are older than 60. The disorder also strikes more men than women.

Signs and Symptoms

Patients in the early stages of disease show few if any symptoms. As a myelodysplastic syndrome progresses, typical signs include fatigue, paleness, unusual bruising or bleeding and shortness of breath.

Many patients experience tiny red spots beneath the skin as the result of bleeding. Some contract frequent infections.

Symptoms of myelodysplasic syndrome are linked to the severity of the disease. The disorder is often detected as the result of a routine blood test. Most signs of the illness are the result of low numbers of red or white blood cells or platelets. In the severest cases, patients are at risk for easy uncontrolled bleeding or infectionds that could be life-threatening.

Some afflicted individuals face an increased risk of developing leukemia.

Causes

In the majority of cases, doctors never find out what caused the changes in the patient's bone marrow. Individuals with this disorder have blood cells that remain immature and are defective. Some die within the bone marrow or right after they enter the bloodstream.

Eventually, the number of defective cells exceeds the number of normal blood cells. This leads to conditions like anemia, excessive bleeding and infections.

Types

Experts typically divide myelodysplastic syndromes into two categories. Those in the first group have no known cause. Doctors refer to them as de novo myelodysplastic syndromes.

The second group includes syndromes caused by chemical exposure, chemotherapy or radiation. They're considered more difficult to treat than those in the other group. These disorders are called secondary myelodysplastic syndromes.

Diagnosis and Treatment

Doctors diagnose myelodysplastic syndromes by utilizing blood tests and studying the patient's bone marrow. Because it's often difficult to distinguish these disorders from other diseases with similar symptoms, testing typically occurs several times within a two- to three-month period.

There is no cure for a myelodysplastic syndrome. No standard treatment exists. The focus of treatment for all patients is managing general symptoms like fatigue and preventing infections and bleeding. Some individuals receive blood transfusions to replace missing blood cells or platelets.

Medications called growth factors increase the number of blood cells a patient with a myelodysplastic syndrome produces, reducing the number of required transfusions. Examples are erythropoietin and darbepoietin.

Drugs like azacitidine (brand name: Vidaza) and decitabine (Dacogen) stimulate the patient's blood cells to mature. However, they cause side effects in some patients and don't work for all individuals.

Medications to suppress the immune system are helpful with certain syndromes. For patients with a specific genetic abnormality known as isolated del(5q), lenalidomide (Revlimid) has sometimes helped avoid the need for transfusions.

Doctors recommend that some patients undergo a bone marrow stem cell transplant. However, even among young patients who are also relatively healthy, this procedure causes many complications.

Patients with myelodysplastic syndromes can reduce their risk of infections through practical home care. This includes washing hands frequently, being careful to clean and thoroughly cook food as necessary and to avoid contact with individuals who are sick.

Sources:

http://www.mayoclinic.com/health/myelodysplastic-syndromes/DS00596

http://www.marrow.org/PATIENT/Undrstnd_Disease_Treat/Lrn_about_Disease/MDS/