TLC Full Form

TLC stands for Total Leukocyte count is done to count the white blood cells ( WBC) or Leucocytes . These leucocytes are the part of the defence system of our body that fights with the incoming infection to keep us fit and healthy.TLC is one of the tests which is done as a part of the total blood count test which is the main test to evaluate the general health of our body .

Definition

Total Leukocyte count or White blood cell count is a blood test used to count the white blood cells in the body.

White blood cells are known as leucocytes ( leuk meaning “white ” and cyt meaning cell)and are an important part of our immune system. This helps in fighting infections by bacteria, viruses and germs .WBCs originate in Bone marrow and circulate throughout the blood .

Types 

There are five major types of leucocytes, these are as follows -:

• Acidophil / Eosinophils( 2-4 %)-The count fluctuates during the menstrual cycle and along the day .It rises in response to allergies,collagen disease, diseases of the Central nervous system. They are rare in blood.The mainly deal with parasitic infection and predominate during allergic reactions
• Basophils( 0.5-1%)- They are chiefly responsible for allergic responses.They release chemicals like histamine to relax blood vessels.They are rarest type of white blood cells and hence our difficult to study .They mainly excrete two chemicals – histamine and heparin.They also create chemical signals to attract Eosinophils and neutrophils to the infection site 
• Neutrophils(55-73%)- They are the most abundant and the first responders that come for defence during a bacterial or fungal infection.The average life cycle of a neutrophil cell is from 5 -153 hours
• Monocytes(2-8%)- With the neutrophils they share the phagocytosis functions or the vacuum cleaning function.They are longer lived than neutrophils as they have other functions like they give pieces of pathogen to T cells. That they can recognise them  and next time when they invade they are killed.So they help in generating an antibody mediated response.After leaving bloodstream they reach tissue where they act as tissue macrophages that remove cell debris and attack microorganisms
• Lymphocytes- It contains T cells and B cells and Natural killer cells .(20-40%)They are common in the lymphatic system. Here B cells make antibodies that block pathogen invasions and the T cells are known as helper cells they help in production of an army of antibodies against the incoming infection.Natural killer cells on the other hand kill cells that don’t display MHC class -1 molecules

Other names of the test 

TLC test is known by the following names – White blood cell count, White blood cell differential , leukocyte count .

Preparation of the test 

Prior to the test a blood sample is taken from the patient. After which you need to tell the health care provider about the medicines you’re taking since the drugs may change the test results.

Normal range 

The normal range of TLC is around 4000 – 11000 cells / cubic millimetre of blood.

Low TLC count

A count of less than 4,000 cells / cubic millimetre of blood is below normal

A decrease in leucocytes is an indication of leukopenia that will further decrease our ability to fight

A lower TLC count may be due to :

• Bone marrow deficiency or failure due to infection or tumour
• Cancer treating drugs or other medicines like captopril, chemotherapy drugs, sulfonamides,Chlorpromazine , ticlopidine 
• Liver or spleen diseases
• Severe bacterial infection
• Viral illnesses like mononucleosis
• Physical or emotional stress due surgery
• Autoimmune diseases  such as lupus 

Higher TLC count 

An increase in TLC is known as leukocytosis and is an indication of acute inflammation and infection.

It may also be due to the following reasons-:

• Cigarette smoking
• Tissue damage
• Bacterial infections
• Spleen removal surgery
• Certain drugs or medicines like heparin, lithium, epinephrine, corticosteroids and other granulocyte stimulating factors.
• Leukaemia and Hodgkin’s disease
• Allergy or anY other inflammatory disease

Need for TLC test 

Mainly this test is performed to know the white blood cell count. Se other reasons to perform a TLC test is to -:

• Diagnose infection
• Diagnose bone marrow disorder
• Monitor chemotherapy treatment
• Inflammation detection
• Allergic reaction
• Blood cancer such as leukaemia or lymphoma

Risks

Taking blood from your body have some minor risks. These are follows-:

• Excessive Bleeding
• Hematoma is a condition in which blood accumulates under the skin
• Infection
• Fainting or feeling lightheaded
• Multiple punctures to locate the vein

Conclusion

TLC count is a part of total blood count. The test is crucial in diagnosing and monitoring various conditions like cancer or any liver or spleen disorder.