What is hematology?

Hematology is the study of blood and blood disorders. Hematologists and hematopathologists are highly trained healthcare providers. They specialize in diseases of the blood and blood components. These include blood and bone marrow cells. Hematological tests can help diagnose anemia, infection, and hemophilia. They also include blood-clotting disorders, and leukemia.

What is the difference between a hematologist and a hematopathologist?

  • Hematologist. This is often a medical doctor who is a board-certified internist or pediatrician who has completed additional years of training in hematology. A hematologist usually focuses on direct care of people. They diagnose and manage hematologic disease. This includes cancers of the blood and bone marrow.

  • Hematopathologist. This is often a medical doctor who is board-certified in both anatomical and clinical pathology. They also have additional years of training in hematopathology. Hematopathology is the study of disease of the blood and bone marrow. It is also the study of the organs and tissues that use blood cells to do their physiologic functions. These include the lymph nodes, the spleen, and thymus. They also include other lymphoid tissue. The hematopathologist focuses on diagnosing conditions of the hematopoietic and lymphocyte-rich tissues. This is often done by direct exam of tissue and blood in the lab. 

Common hematology tests



Complete blood count (CBC), which includes:

  • White blood cell count (WBC)

  • Red blood cell count (RBC)

  • Platelet count

  • Hematocrit red blood cell volume (HCT)

  • Hemoglobin concentration (HB). This is the oxygen-carrying protein in red blood cells.

  • Differential white blood count

  • Red blood cell indices (measurements) 

To help diagnose anemia, certain cancers of the blood, and inflammatory diseases. Also to watch for blood loss and infection.

Platelet count (often done as part of the CBC) 

To diagnose or to watch certain types of bleeding and clotting disorders

Prothrombin time (PT)

Partial thromboplastin time (PTT)

International normalized ratio (INR) 

To evaluate bleeding and clotting disorders. Also to watch anticoagulation (anticlotting) therapies.

Bone marrow biopsy is not a common test in general. But it is a common test for hematologists. It includes taking cells from the bone marrow for analysis for many types of diseases. 

Online Medical Reviewer: Mahammad Juber MD
Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Rita Sather RN
Date Last Reviewed: 9/1/2023
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.