Haematology

Haematology is the study of disorders of blood and the blood forming organs, lymphomas and the lymphoreticular system. It is a speciality which includes the preventive, diagnostic and management aspects dealing with the aetiology, pathophysiology, investigation, diagnosis and management. Sometimes one consultant does all of above at other times a clinical Haematologist manages patients and a laboratory Haematologist diagnoses and advices other clinicians on management of the disorders.

The diseases are developmental, reactive and malignant which arise in the bone marrow, in the cells of the blood and the platelets. Disorders of the coagulation system are also categorised with diseases of the blood as it is the cause of bleeding and blood clot (thrombus) forming disorders.

Thus thalassaemias where decreased synthesis of various protein chains in the haemoglobin (Hb) molecule, sickle cell anaemia where the globin chains of the Hb molecule is abnormal belong to the haemoglobinopathies.

Infections like dengue, malaria, affect platelets and the red cells respectively. In leukaemias, lymphomas and myeloma cells which arise in the bone marrow have become malignant causing what are commonly known as blood cancers.

Some of the investigations (laboratory and other tests) used in the diagnosis at LHD are:

• Complete blood count (CBC)
• Blood picture
• ESR
• Prothrombin Time(PT), Activated Partial Thromboplastin Time (aPTT), Thrombin Time (TT), Fibrinogen, D-dimers, Protein C, Protein S
• Hb capillary Electrophoresis(HbCapE)
• G6PD
• Osmotic Fragility Test

At LHD, the haematology related tests are used to identify a variety of diseases including:

• Anaemia: Occurs when the body does not have enough red blood cells or have red cells carrying abnormal haemoglobins, as the haemoglobin within the red cell distributes oxygen throughout the human body.
• Immunodeficiency: when the white blood cells are either low in number or defective in function the immune system function is compromised. People with such disorders like HIV infections, leukaemias and people on chemotherapy are susceptible to infections.
• Leukaemia: A form of cancer of blood cells are known to affect the function of normal blood cells.
• Clotting or Bleeding Disorders: When various coagulations factors are not produced or are produced in low quantity bleeding or clotting disorders occur. As normal platelets are intrinsic to the normal clotting of blood they too are included in the cause of bleeding disorders when abnormal in number or function.
• Bone Marrow Disorders: Known to arise by defective stem cells, nutritional disorders, developmental anomalies, infections and cancerous change as it is the site of production of blood cells.