Last updated on 5th Sep 2022 - By Dwayne Michaels

Why is my mch high or low?

The MCH results are interpreted along with the results for MCHC to help diagnose disease severity. So let's know about all these tests and let's try to know the real cause of your disease.

After reading this article thoroughly you will be able to self-diagnose your disease

Before understanding the RBC indices such as MCV, MCH, MCHC and RDW, let us know some of the causes of abnormal red blood cells.

Causes of a low RBC count:

  • Loss of blood
  • Iron deficiency, vitamin B12 or folate deficiency
  • Kidney failure
  • Sudden or chronic bleeding from the digestive tract (e.g., ulcers, polyps, colon cancer) or other sites
  • Chronic inflammatory disease
  • Bone marrow damage
  • Hemolytic anemia caused by autoimmunity or defects in the red cell itself
  • Bone marrow disorders such as leukemia, multiple myeloma, myelodysplastic syndrome, or lymphoma or other cancers that spread to the bone marrow

Causes of a high RBC count:

  • Dehydration
  • Lung disease
  • Congenital heart disease
  • Smoking
  • Kidney tumor that produces excess erythropoietin
  • Polycythemia vera

If you need our help diagnosing the severity of your illness and want to fix your problem, you can upload your blood report here. Upload blood test report now

If your doctor finds any abnormalities in your hemoglobin, hematocrit (also called packed cell volume) or RBC levels, he may order one of the most common blood tests called the RBC index. The RBC indices include measurements of MCV, MCH and MCHC.

Let's know about these blood tests:

MCV:

Mean corpuscular volume (MCV) measures the mean or average size of individual red blood cells. To obtain the MCV, the hematocrit is divided by the total RBC count. The MCV is an indicator of the size of red blood cells.

In patients with anemia, it is the MCV measurement that allows classification as either a microcytic anemia (MCV below normal range), normocytic anemia (MCV within normal range) or macrocytic anemia (MCV above normal range).

For further specification, it can be used to calculate red blood cell distribution width (RDW). The RDW is a statistical calculation made by automated analyzers that reflects the variability in size and shape of the RBCs.

The normal reference range is typically 80-100 fL. In pernicious anemia (macrocytic), MCV can range up to 150 femtolitres.

Vitamin B12 and/or folic acid deficiency has also been associated with macrocytic anemia (high MCV numbers).

The most common causes of microcytic anemia are iron deficiency (due to inadequate dietary intake, gastrointestinal blood loss, or menstrual blood loss), thalassemia, sideroblastic anemia or chronic disease. In iron deficiency anemia (microcytic anemia), it can be as low as 60 to 70 femtolitres. In some cases of thalassemia, the MCV may be low even though the patient is not iron deficient

A correct diagnosis can only be made by comparing your MCV abnormality with other blood abnormalities.

If you need our help diagnosing the severity of your illness and want to fix your MCV problem, you can upload your blood report here. Upload blood test report now

MCH:

Mean corpuscular hemoglobin (MCH) measures the amount, or the mass, of hemoglobin present in one RBC. The weight of hemoglobin in an average cell is obtained by dividing the hemoglobin by the total RBC count.

Hemoglobin is the protein in your red blood cells that transports oxygen to the tissues of your body. Your MCH value is related to two other values, mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC).

A normal MCH value in humans is 27 to 33 picograms (pg)/cell.

A low MCH value typically indicates the presence of anemia. Different types of anemia can cause low MCH levels. For example, microcytic anemia occurs when the blood cells are too small and cannot take in as much hemoglobin as they should. Celiac disease can also lead to low MCH levels. Low MCH levels can also appear in a body that is lacking key vitamins.

Complications from liver disease, infection or certain cancers can also cause high MCH levels.

Though they are very similar, MCH levels should not be confused with MCHC levels. In more rare cases, low MCH can be caused by a genetic condition called thalassemia.

High MCH value can often be caused by anemia due to a deficiency of B vitamins, particularly B-12 and folate.

A correct diagnosis can only be made by comparing your MCHC abnormality with other blood abnormalities.

If you need our help diagnosing the severity of your illness and want to fix your MCH problem, you can upload your blood report here. Upload blood test report now

MCHC:

Mean corpuscular hemoglobin concentration (MCHC) measures the proportion of each cell taken up by hemoglobin. The results are reported in percentages, reflecting the proportion of hemoglobin in the RBC. The hemoglobin is divided by the hematocrit and multiplied by 100 to obtain the MCHC.

Reference ranges for blood tests are 32 to 36 g/dL (320 to 360g/L), or between 4.81 and 5.58 mmol/L.

A low MCHC can be interpreted as identifying decreased production of hemoglobin. MCHC can be normal even when hemoglobin production is decreased (such as in iron deficiency) due to a calculation artifact.

Low MCHC values occur if you have anemia due to iron deficiency. It can also indicate thalassemia.

MCHC levels can be abnormal due to autoimmune hemolytic anemia, macrocytic anemia, hereditary spherocytosis, liver disease, thyroid problems, and many other reasons.

MCHC can be elevated in some megaloblastic anemias. MCHC can be falsely elevated when there is agglutination of red cells (falsely lowering the measured RBC) or when there is opacifaction of the plasma (falsely increasing the measured hemoglobin). Causes of plasma opacification that can falsely increase the MCHC include hyperbilirubinemia, hypertryglyceridemia, and free hemoglobin in the plasma (due to hemolysis).

The MCH and the MCHC are used to assess whether red blood cells are normochromic, hypochromic, or hyperchromic.

A correct diagnosis can only be made by comparing your MCHC abnormality with other blood abnormalities.

If you need our help diagnosing the severity of your illness and want to fix your MCHC problem, you can upload your blood report here. Upload blood test report now