This chapter explains normal blood functions, including hemopoiesis and hemostasis. Clinical conditions covered include anemia, hemorrhage, polycythemia, iron overload, hemochromatosis, erythropoiesis abnormalities, thrombocytopenia, hemophilia, thrombosis, leukemia and lymphoma. Immunoassays relevant to hematology are reviewed: vitamin B12, folate (including red cell folate), intrinsic factor antibody, ferritin, transferrin, transferrin receptors, erythropoietin, proteins C and S, antithrombin, coagulation factors, fibrinogen, fibrinogen and fibrin degradation products, D-dimer, leukemia and lymphoma analytes, and malarial parasites. Newborn and antenatal screening for hemoglobinopathies is also discussed. For most of the test analytes the biological function is explained, with the clinical applications of the test and its limitations. Typical assay technology is also described. The type of sample and frequency of use are included, with an example reference interval (for background information only). For some analytes, desirable assay performance characteristics are included.

Katy Evans is a Clinical Scientist at the Royal Devon and Exeter Hospital, UK. She completed a PhD in Molecular Haematology in 2009 and went on to qualify as a Clinical Scientist in Haematology in 2010. She has a specialist interest in haemato-oncology and has gained considerable experience using laboratory techniques for the diagnosis and monitoring of haematological malignancies.

Dr. Zane Amenhotep is a practicing pathologist in San Francisco, California who holds board certifications in anatomic and clinical pathology and hematopathology. He is currently on faculty at the University of California, San Francisco as a Health Sciences Assistant Clinical Professor in the Department of Laboratory Medicine and serves as Chief of the Transfusion Medicine and Hematology Laboratory Divisions of the Clinical Laboratory at San Francisco General Hospital and Trauma Center. His clinical interests include the diagnosis of benign, reactive and malignant hematologic disorders and the provision of guidance for safe and appropriate blood product administration with a focus on issues unique to the urban hospital and trauma center setting. His academic interests include the development of educational methods and learning curricula for medical student, resident and clinical laboratory scientist education and training in hematopathology and transfusion medicine.

Hematology, blood, red blood cell, white blood cell, clotting, coagulation, hemopoiesis, erythron, hemoglobin, hemostasis, fibrinolysis, von Willebrand factor, plasminogen, tissue plasminogen activator, plasmin, anemia, hemorrhage, polycythemia, iron overload, hemochromatosis, erythropoiesis, thrombocytopenia, hemophilia, thrombosis, intrinsic factor, leukemia, lymphoma, vitamin B₁₂, folate, intrinsic factor antibody, ferritin, transferrin, transferrin receptor, erythropoietin, protein C, protein S, antithrombin, coagulation factors, fibrinogen, fibrinogen degradation products, fibrin degradation products, D-dimer.

Testing algorithms for hemochromatosis and hemolytic anemia are available at www.arupconsult.com/algorithms/or.html.