Hematology, also spelled haematology, is the branch of medicine concerned with the study of the cause, diagnosis, treatment, and prevention of diseases related to blood.It involves treating diseases that affect the production of blood and its components, such as blood cells, hemoglobin, blood proteins, bone marrow, platelets, blood vessels, spleen, and the mechanism of coagulation. Such diseases might include hemophilia, blood clots, other bleeding disorders and blood cancers such as leukemia, myeloma, and lymphoma.
The laboratory work that goes into the study of blood is frequently performed by a medical technologist or medical laboratory scientist. Many hematologists work as hematologist-oncologists, also providing medical treatment for all types of cancer. The term is from the Greek αἷμα, haima meaning “blood,” and -λoγία meaning study.
Patients are referred to General Haematology by GPs and hospital doctors.
The commonest reasons for referral to the general clinic are the finding of abnormalities on the blood count or symptoms experienced by the patient that the referring doctor thinks may be caused by a disease of blood, bone marrow or sometimes the lymph nodes.
The kind of abnormalities in the blood count include the following.
- Anaemia – low haemoglobin or red blood cells
- Leucopenia – low white cells
- Thrombocytopenia – low platelets
- Polycythemia – too many red blood cells
- Leukocytosis – too many white blood cells
- Thrombocytosis – too many platelets
Many people referred to these clinics worry that they have a cancerous illness. This will be true for some, but the majority of patients referred to the general clinic do not have cancer. All patients being seen in the clinic will be discussed with a consultant and most will see a consultant on their first visit. Often additional investigations are required to help to make a diagnosis. These may include additional blood tests, and some patients will also need X-rays, scans and/or a bone marrow test. If these tests are requested the patient will be seen with the results. Many patients can
then be discharged from the Haematology Clinic, but some will need further investigation and treatment in a clinic specific for the type of illness which has been diagnosed.