Hematology is the study of blood and its disorders. Hematologists are specially trained doctors who look specifically at blood components, such as blood count, and blood and bone marrow cells. Hematological tests can help diagnose anemia, hemophilia, blood-clotting disorders, and leukemia.
A hematologist is usually a board-certified internist, pediatrician, or family doctor who has completed additional years of training in hematology. The hematologist generally focuses on diagnosing and managing hematologic disease, especially cancers.
The hematopathologist is usually board-certified in both anatomical and clinical pathology and has additional years of training in hematopathology. Hematopathology is not only the study of disease of the blood and bone marrow, but also of the organs and tissues that use blood cells to perform their physiologic functions, such as the lymph nodes, the spleen, thymus, and other lymphoid tissue. The hematopathologist focuses on the diagnosis of conditions of the hematopoietic and lymphocyte-rich tissues, usually by direct examination of tissue and blood in the laboratory.
A third type of hematologist is the hematologist/oncologist who specializes in cancers of the blood and organs, stem cells, lymphatics, administration of chemotherapy, as well as other blood processes.
Complete blood count (CBC), which includes:
White blood cell count (WBC)
Red blood cell count (RBC)
Hematocrit red blood cell volume (HCT)
Hemoglobin concentration (HB). This is the oxygen-carrying pigment in red blood cells.
Differential white blood count
Red blood cell indices (measurements)
To aid in diagnosing anemia, certain cancers of the blood, inflammatory diseases, and to monitor blood loss and infection
Platelet count (usually done as part of the CBC)
To diagnose and/or to monitor bleeding and clotting disorders
Prothrombin time (PT)
Partial Thromboplastin Time (PTT)
International Normalized Ratio (INR)
To evaluate bleeding and clotting disorders and to monitor anticoagulation (anticlotting) therapies
Bone marrow biopsy is not a common test in general, but is a common test for hematologists. It involves taking cells from the bone marrow for analysis for many types of disease.