A blood test is one of the most powerful and versatile diagnostic tools in medicine. A single blood draw can reveal dozens of pieces of information about your health — from the number and type of blood cells circulating in your body, to how well your liver and kidneys are working, to your blood sugar and cholesterol levels. Understanding the basics helps you engage more actively in your own healthcare.
Complete Blood Count (CBC)
The CBC is the most fundamental blood test, evaluating the three major types of blood cells:
Red blood cells and related values:
- RBC (Red Blood Cell count): The total number of red blood cells. A low count may indicate anaemia.
- Haemoglobin (Hb/Hgb): The protein in red blood cells that carries oxygen. Low haemoglobin is the defining feature of anaemia.
- Haematocrit (Hct): The percentage of your total blood volume made up of red blood cells.
- MCV (Mean Corpuscular Volume): The average size of your red blood cells. This helps classify the type of anaemia — small cells often suggest iron deficiency, while large cells may point to vitamin B12 or folate deficiency.
White blood cells:
- WBC (White Blood Cell count): A high count usually signals infection or inflammation; a very low count may indicate an immune system problem.
- Differential count: Breaks down the WBC into its five types — neutrophils, lymphocytes, monocytes, eosinophils, and basophils. The pattern of change helps identify the likely cause of an abnormality.
Platelets:
- PLT (Platelet count): Platelets are essential for blood clotting. A very low count raises the risk of bleeding; an abnormally high count also warrants monitoring.
Liver Function Tests (LFTs)
- ALT (SGPT) and AST (SGOT): Liver enzymes released when liver cells are damaged. Elevated levels are commonly seen in hepatitis, alcohol-related liver disease, and certain medications.
- Bilirubin: A waste product from the breakdown of red blood cells, processed by the liver. High levels cause the yellow skin and eyes seen in jaundice.
- Albumin: A protein produced by the liver. Low levels can indicate chronic liver disease or malnutrition.
- GGT and ALP: Additional enzymes that assess bile duct function and liver health.
Kidney Function Tests
- Creatinine: A waste product from muscle metabolism that the kidneys filter out. Elevated levels suggest the kidneys are not filtering efficiently.
- Urea (BUN — Blood Urea Nitrogen): A nitrogen waste product from protein breakdown. High levels can indicate kidney problems or dehydration.
- eGFR (Estimated Glomerular Filtration Rate): Calculated from creatinine, age, and other factors, this value estimates how well your kidneys are filtering blood. It is the key number used to stage chronic kidney disease.
Blood Sugar and Lipids
- Fasting glucose: Measured after at least 8 hours without food. A value below 100 mg/dL is normal; 100–125 mg/dL is pre-diabetes; 126 mg/dL or above on two separate occasions indicates diabetes.
- HbA1c: Reflects average blood glucose over the past three months — the primary tool for monitoring diabetes management.
- Total cholesterol, LDL, HDL, and Triglycerides: Assess cardiovascular risk. High LDL (“bad cholesterol”) and low HDL (“good cholesterol”) increase the risk of artery disease and heart attack.
Important Things to Know
- Results should always be interpreted by a doctor in the context of your full clinical picture — a value outside the reference range does not automatically mean you have a disease.
- Many tests require fasting for 8–12 hours beforehand for accurate results. Follow your clinic’s instructions.
- Reference ranges may vary slightly between laboratories depending on equipment and units used.
Regular blood tests are an essential part of a comprehensive health check-up. At Ky Hoa Medical Center, our laboratory is equipped with modern analysers that deliver fast and reliable results. Our doctors are available to review your results with you, explain what they mean, and recommend next steps tailored to your individual health profile.