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Patient Recruitment

Clonal Cytopenia of Undetermined Significance (CCUS)

Do You Have Low Blood Counts and a Genetic Mutation?

a vial of blood

a magnifying glass over cells

Doctors at the National Institutes of Health (NIH) are conducting a study on patients with Clonal Cytopenia of Uncertain Significance (CCUS). Patients with CCUS have low blood counts and a normal bone marrow exam but more advanced genetic testing shows the presence of a genetic mutation that is likely causing the low counts. The study will look at CCUS and try to determine its relationship to blood cancers and heart disease. The study will also try to discover other new organs or diseases it may be linked with.

Study Involves:

  • Yearly medical evaluations over a 10-year period
  • Blood and urine sampling
  • Heart and liver imaging, lung function testing, DEXA scan
  • Optional CT coronary angiography and PET/CT
  • Travel, lodging and compensation for procedures

You may be eligible if you:

  • Are at least 18 years old
  • Have a diagnosis of clonal cytopenia of uncertain significance (CCUS) or have unexplained low blood counts and have not yet undergone genetic testing
  • Have not had a formal diagnosis of blood cancer or myelodysplastic syndrome
  • Have not been previously treated with chemotherapy or radiation
  • Have no other hematological diagnosis causing your low blood counts

The NIH Clinical Center, America's Research Hospital is located on the Metro red line (Medical center) in Bethesda, Maryland. There is no charge for study-related tests, medications or procedures. Travel assistance may be provided.

For more information:
NIH Clinical Center
Office of Patient Recruitment
800-411-1222 (refer to study # 19-H-0139)
800-877-8339 TTY / ASCII
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Or go online:

Department of Health and Human Services
National Institutes of Health Clinical Center (CC)
National Heart, Lung and Blood Institute (NHLBI)

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This page last updated on 10/22/2021

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