Blood Test Results and their Meaning

A blood test helps assess a health problem. Doctors generally order a blood test to confirm the diagnosis. Other tests like urine test, stool test, ultrasonography, etc. are also ordered along with a blood test, as these tests help detect the exact cause of the illness. While understanding blood test results and their meaning, you need to know the reference range of the blood components measured. It is generally provided with an asterisk or in a separate column or in the footnote. Here follows information on how to read and understand medical laboratory results of a blood test.

Reading the Blood Test Results

If the question how to read blood test results is lingering in your mind, then you should first try to understand the medical terms or abbreviations used to describe the blood components. Understanding the meaning of the blood test results is easier if you know what are the reference ranges of the elements present in blood and what do fluctuations in normal values indicate. You should discuss abnormal values with your doctor. There is no need to interpret the results hurriedly, it should be left to the doctor. There are always chances of false positive and false negative results, and blood test is not the only way to diagnose a problem. The doctor may order some more tests or he may order another blood test, again after a few days, to confirm the diagnosis. Here follows information on commonly ordered blood tests and normal values of blood components measured. Take a look at the blood test results explained below.

Blood Test Results: Meanings

Complete Blood Count
A CBC blood test is ordered to know the type and the number of cells present in your blood.

Description	Normal Range
Red Blood Cell (RBC) Count: Male	4.7 to 6.1 million cells/mcL (cells per microliter)
Red Blood Cell (RBC) Count: Female	4.2 to 5.4 million cells/mcL
White Blood Cell (WBC) Count	4,500 to 10,000 cells/mcL
Hematocrit: Male	40.7 to 50.3 %
Hematocrit: Female	36.1 to 44.3 %
Hemoglobin: Male	13.8 to 17.2 gm/dL (grams per deciliter)
Hemoglobin: Female	12.1 to 15.1 gm/dL
Mean corpuscular volume	80 to 95 femtoliter
Platelets	140,000 to 450,000 cells/mcL
Mean corpuscular hemoglobin (MCH)	27 to 31 pg/cell (picograms per cell)
Mean corpuscular hemoglobin concentration (MCHC)	32 to 36 gm/dL

RBC count may vary with altitude. The normal values may vary according to the age and race too. Above values are for adults only. A MCV blood test helps measure 'mean corpuscular volume'.

Thyroid Hormone Test
A TSH blood test is ordered to find out the reason behind the dysfunction of the thyroid gland. The thyroid stimulating hormone (TSH) helps control the level of thyroid hormones in your body. The following chart explains the TSH blood test results and their meaning.

TSH Level Status	TSH Level Count
Normal TSH Levels	0.4 - 4.0 mIU/L
Underactive Thyroid	2.0 mIU/L or more
Thyroid Disorder	0.5 to 3.0 mIU/L

CMP Blood Test
A CMP or Comprehensive Metabolic Panel blood test helps determine the mineral content, physiological state, organ function, biochemical state, etc. of a person. In all, 14 tests constitute CMP blood test. They are performed to measure blood sugar; protein levels (blood serum albumin); calcium, sodium, potassium, carbon dioxide and chloride levels; blood urea nitrogen (BUN), creatinine (to detect dysfunction of kidneys), etc. Measurement of bilirubin, alkaline phosphate (to determine liver function) test, alanine aminotransferase test (ALT) and aspartate transaminase (AST) test help assess the liver function. The following chart explains the normal values of blood components measured in the CMP blood test.

Name of the Component	Normal Range
Blood Glucose	64 -128 mg/dL
Human Serum Albumin	HSA - 3.9 to 5.0 g/dL
Human Serum Protein	TP (total protein) - 6.3 to 7.9 g/dL
Calcium	8.5 - 10.9 mg/dL
Electrolytes	Sodium - 136 to 144 mEq/L, Potassium - 3.7 to 5.2 mEq/L, Carbon Dioxide - 20 to 29 mmol/L, Chloride - 101 to 111 mmol/L
Blood Urea Nitrogen	7 - 20 mg/dL
Creatinine	0.8 to 1.4 mg/dL (varies with age)
Alkaline Phosphatase	44 to 147 IU/L
Alanine Aminotransferase	8 to 37 IU/L
Aspartate Aminotransferase	10 to 34 IU/L
Bilirubin	0.2 to 1.9 mg/dL

CPK Blood Test
A CPK blood test or creatine phosphokinase test helps detect muscle damage in your body. Muscle cells contain a large amount of CPK enzyme. If a muscle is injured, muscle cells open up and spill out CPK into the blood. Therefore elevated CPK levels indicate muscle injury. Normal levels of CPK in healthy men are somewhere around 38 - 174 units/L and in healthy women, around 96 - 140 units/L. The CPK test is useful in diagnosing chest pain, heart attack, muscular dystrophy, brain injury, stroke, convulsions, myocarditis, etc.

Remember, blood test results and their meaning may vary from laboratory to laboratory. Normal values of blood components may vary slightly from lab to lab and from country to country. Besides, you should always check the unit of measurement. Values will vary according to the unit. Handling of blood samples, intake of certain medications, foods, beverages, menstrual cycle, estrogen level, intake of birth control pills, physical activity and even psychological stress can affect the blood test results. You should not panic after seeing abnormal values. Sometimes, blood test results' meaning and final diagnosis can be different because blood test is not the only way to diagnose a disease. However, blood tests are useful for early detection of life-threatening problems like cancer. With prompt treatment and lifestyle changes, one can recover fast, if the condition is detected at an earlier stage.