Clinical Hematology Test: Introduction, List of Tests, Specimen Requirement, Testing Method, and Keynotes

Introduction of Clinical Hematology Test

Clinical Hematology is the branch of laboratory medicine pertaining to the study of blood, blood-forming organs, and blood diseases. Hematology tests include laboratory estimation of blood formation and blood disorders. e.g. Complete blood count (CBC)- A count of the total number of red blood cells (RBCs), white blood cells(WBCs), and platelets present in the blood. Peripheral blood smear (PBS)/blood film – Blood is smeared over a clean and grease-free glass slide that is stained with specific dyes and observed under a compound microscope.

The number, shape, and size of blood cells and the presence of any abnormal cells or immature cells are noted and the staining may also detect blood parasites such as Plasmodium species, Toxoplasma gondii, and microfilaria. The erythrocyte sedimentation rate (ESR) test is used to diagnose conditions that cause inflammation like temporal arteritis, autoimmune diseases, cancers, and infections. Prothrombin time (PT) test and activated partial thromboplastin test (APTT) may also be checked for platelet function in bleeding and coagulation. D-dimer test may be performed to check for thrombotic disorders. Electrophoresis is also beneficial to examine proteins in the blood such as hemoglobin and to check for hemoglobinopathies such as thalassemia or sickle cell anemia. The enzyme G6PD is tested in sickle cell disease.

List of Hematology Tests, Specimen Requirements, Testing Method

List of Tests	Specimens Requirement	Testing Method
Absolute Eosinophil Count	EDTA blood (2 ml)	Automated cell counter/ Microscopy
Complete Blood Count (CBC)	EDTA blood (3 ml)	Automated cell counter(Fluorescence flow cytometry/electrical impedance)
Erythropoietin(EPO)	Serum (1 ml)	CLIA
ESR	Citrated plasma (2 ml)	Westergren method
Fibrinogen Degradation Products(FDP) (Semi-Quantitative )	Citrated plasma (2 ml)	Latex Particle Agglutination
Fibrinogen Level	Citrated plasma (2 ml)	Clot-based (Clauss)
Glycosylated Haemoglobin (HbA1c)	EDTA blood (2 ml)	HPLC/NycoCard
Reticulocyte Count	EDTA blood (2 ml)/serum (3 ml)	Microscopy/Spectrophotometry
Sickle cell screening	EDTA blood (2 ml)	HPLC

Keynotes on Clinical Hematology Test

• CBC and ESR are the common tests requested by clinicians (doctors).
• A prothrombin time (PT) test is common prior to the surgery of patients.
• The Clinical Hematology Laboratory works closely with numerous sections of laboratory medicine like Flow Cytometry, Molecular Diagnostics, and Cytogenetics to provide comprehensive, clinical diagnostic care for a range of disorders.
• HPLC stands for high-performance liquid chromatography.
• CLIA stands for chemiluminescence immunoassay analyzer.
• The full form of EDTA is ethylenediamine tetra acetic acid.

Haematology Test- Test Result, Unit, Normal Range, and Test Methods