What is Mean corpuscular volume (MCV)
MCV, which stands for, mean corpuscular volume or mean cell volume, is an analysis of red blood cell volume (RBC). This test is commonly a part of the complete blood count test (CBC) or can be taken independent of the complete blood count test. Doctors recommend the MCV test to patients who they suspect to have anemia, thalassemia, vitamin B12 deficiency and iron deficiency or who suffer from them. This test is essential for patients having normal hemoglobin content but still suffer from anemia.
Conducting the MCV blood test
To conduct an MCV test, a laboratory technician collects blood sample from the vein of the patient at the back of hand or the inside elbow. One of the risks with such blood test is as veins are not unique and vary in size, while obtaining a blood sample one has to consider this. Other risks include excessive bleeding, infections, hematoma and fainting or feeling light leaded. When one considers all the risks with giving a MCV blood sample and getting the test complete, it is always better have them in a reputable laboratory and on consulting a doctor. This ensures safety and right guidance.
Why the Test is Performed
Similar to other blood tests, the main intention of this test as well is to check if the patient is suffering from any disease. When the MCV value is either high or low, it indicates the patient having an ailment. The red blood cells are larger than the normal size, when the MCV value is high, and if the MCV value is low, the red blood cells are smaller than the normal. Red blood cells carry oxygen from the lungs to cells; when they are abnormal it does affect one’s health.
For patients with anemia (or a low RBC), the MCV value determines if the anemia is microcytic, normocytic or macrocytic. When the MCV value is below the normal range, it is microcytic when in the normal range it is normocytic and when above the normal range, it is macrocytic anemia. The MCV value is a division of erythrocyte volume fraction by count of red blood cell, and its unit of measure is femtolitres. The normal range of MCV is 80 to 100 FL. The MCV results have to be in tandem RBC morphology, any deviation in these values indicates technician error or faulty equipment.
Below are a list of symptoms you may experience due to abnormal RBC levels.
Symptoms that identify anemia are:
- leg cramps
- difficulty in concentration
- shortness of breath
- pale skin
- rapid heartbeat
- easy fatigue
- loss of energy
Anemia B12 Deficiency
For patients suffering from iron deficiency anemia, they would have a strange crave for food such as ice, paper or dirt and are prone to soreness and cracks of the mouth.
Symptoms of B12 deficiency anemia are:
A RBC Virus caused by Anemia
When the MCV values are not normal, it is probably anemia. The value of MCV establishes the cause of anemia.
- microcytic anemia (MCV below normal range)
- normocytic anemia (MCV within normal range)
- macrocytic anemia (MCV above normal range)
Normal MCV Levels
- Men over 18 years old: 78 – 98 um3
- Women over 18 years old: 78 – 98 um3
- Newborn: 95 to 121 um3
- Newborn to puberty: 3 to 13 mm/hr
- 6 months to 2 years: 70 to 86 um3
- Boys between 12 to 18 years old: 78 to 98 um3
- Girls between 12 to 18 years old: 78 to 102 um3
Note: um3 = (cubic micrometers)
Low MCV Levels
RBCs are smaller (microcytic) and is likely microcytic anemia which is linked to a haemoglobin disorder such as thalassaemias, vitamin B12 deficiency, iron deficiency, chronic disease, bone marrow disorders, pregnancy or anaemia due to blood cell destruction.
Why are the MCV Levels Low?
There are numerous possible explanations precisely why the MCV level could end up being low. One explanation is due to lead poisoning. Long term kidney failure may also increase the risk for MCV level being too low. A lengthy decrease of iron within the body could cause lower MCV levels. Amemia could also result in a very low MCV level. Anemia is known as a symptom in which there is definitely an abnormally low quantity of hemoglobin in the blood.
High MCV Levels
When the MCV is above the normal range it is likely macrocytic anemia and may be linked to iron deficiency, bone marrow abnormalities, liver disease, chronic lung disease, alcoholism, nutritional deficiencies.
Why are the MCV Levels High?
There are several feasible explanations why the MCV level may be too high. One particular explanation is due to liver disease. The liver is the most significant body organ which is accountable for blocking damaging chemical substances, generating essential chemicals for the body, along with other essential capabilities. Cirrhosis is a form of disease that damages the liver and could cause higher MCV levels. A different reason for a higher MCV level is alcohol abuse.