The biggest problem in Haematology is definitely Anaemia which means low Haemoglobin. Haemoglobin is the pigment in red blood cells which carry Oxygen and gives red colour to blood.Anaemia can be due to different reasons:

• Iron Deficiency: Commonest cause in India. This can be due to malnutrition, poor diet, bleeding from gut (ulcers, piles, cancers, hookworm infestation), heavy periods, bleeding in the urine(Haematuria), pregnancy. Treatment is usually with oral Iron replacement. Sometimes Iron can be given through veins. Very occasionally blood transfusion is required.
• Vitamin B12 Deficiency: Very common among vegetarians as Vitamin B12, an essential component of blood formation is lacking in vegetarian diet. Treatment is usually by replacing Vitamin B12 either by oral tablets or by intramuscular or intravenous Vitamin B12. Pernicious Anaemia is a very rare form of Vitamin B12 Deficiency that runs in families.
• Folic Acid Deficiency: Folic Acid is another vitamin essential for blood formation. It is plentiful in green leafy vegetables. Diet lacking in green leafy vegetables can give rise to Folate-Deficiency Anaemia. It can also occur in alcoholics whose diet often lacks Folic Acid. Pregnant patients are also deficient in Folates and replacing Folic acid during pregnancy is essential.
• Kidney failure: Kidney produces Erythropoietin, a hormone essential for blood formation. So kidney disease is a big reason for patients suffering from anaemia. This situation usually requires treatment with Erythropoietin.
• Liver Disease: Liver damage can also cause anaemia via a variety of mechanisms
• Immune Haemolytic anaemia: In this strange disease, antibodies form against red cells which get destroyed. The patient presents with Anaemia and Jaundice. Direct and Indirect Coomb’s Tests are often positive. Treatment is usually with steroids and judicious blood transfusion.
• Non-Immune Haemolytic Anaemia: These are usually genetic conditions where misshapen red cells get destroyed to Spleen. Examples are Thalassaemias, Sickle Cell Disorders, Hereditary Spherocytosis etc.
• Blood Cancers: All types of blood cancers like Leukaemias, Lymphomas, Myelomas, Myelodysplasias, Myeloproliferative Disoders etc can give rise to anaemia. This is usually due to replacement of normal marrow elements by cancer cells.
• Metastatic Cancers: Different types of solid organ cancers like Liver Cancers, Lung cancers etc can metastatize to the Bone Marrow and cause Anaemia