MCHC blood test normal range and causes and symptoms of low and high mch
Tests & Procedures

What is MCHC Blood Test & Causes, Symptoms of High and Low MCHC

The MCHC blood test is ordered by doctors to check the average concentration of hemoglobin in your blood cells. MCHC stands for Mean Corpuscular Hemoglobin Concentration, and an MCHC test actually expresses the average weight of hemoglobin per unit volume of blood. The MCHC blood test is usually done as part of the Complete Blood Count(CBC) test.

Hemoglobin is an important protein found in red blood cells, and it helps in carrying and supplying oxygen throughout the body. So, having a normal MCHC level indicates that there is a normal level of oxygen in the blood, enough to nourish the body cells and tissues. The normal MCHC levels are considered to be between 32 and 36 grams per deciliter (g/dL).

Along with MCHC values, doctors usually check the average red blood cell size known as MCV or Mean Corpuscular Volume. And the amount of hemoglobin in each red blood cell, known as MCH or Mean Corpuscular Hemoglobin. These two tests are important to understand the reason for anemia despite a person having a normal red blood cell count. Anemia could occur if the red blood cells carry lesser hemoglobin than normal, i.e. if a person has low MCH levels or if the concentration of hemoglobin in each red blood cell is very low, i.e. low MCHC levels.

Usually, an MCHC blood test is ordered along with other specific blood tests when a person shows signs of fatigue and weakness when a person is suffering from an infection, when a person experiences bleeding or bruising easily with very less strain caused to the body, or when a person shows signs of an inflammation.

Low MCHC Causes

A low MCHC test result shows that the person’s red blood cells (RBCs) do not contain enough hemoglobin. Hemoglobin is an iron-rich protein whose deficiency causes anemia. Hemoglobin renders the red color to the RBCs, and as mentioned earlier. It is responsible for carrying oxygen throughout the body. A deficiency of hemoglobin leads to low levels of oxygen in the blood and may cause fatigue and other symptoms of anemia.

The MCHC blood test forms an important part of the blood analysis, and the MCHC value helps doctors recognize the cause and severity of anemia.

Low MCHC test results indicate anemia which may be caused by normal physiological conditions such as pregnancy, or sometimes, life-threatening conditions such as cancer.

Factors that are Responsible for Hemoglobin Deficiency and therefore Low MCHC Blood Test Results Include:

  • Conditions causing the body to produce fewer blood cells
  • Conditions in which the RBCs are destroyed at a faster rate than they are produced in the body
  • Severe blood loss caused by wounds, ulcers, hemorrhoids, or cancers, and sometimes due to frequent blood donation or heavy blood loss during menstruation in women

A Low Hemoglobin Concentration can be Caused by any one of the Following Types of Anemia:

  • Iron Deficiency Anemia: This type of anemia is either caused by a diet that is deficient in iron or due to the inability of the body to absorb iron. Iron deficiency affects the development of RBCs, and the body produces smaller and paler RBCs.                                                                        
    MCH Blood test | Low hemoglobin causes anemia
  • Pernicious Anemia: This type of anemia is caused by a diet that is deficient in Vitamin B12 or when a person’s body is unable to absorb Vitamin B12 from the diet.
  • Aplastic Anemia: This type of anemia is associated with a decrease in the levels of all blood cells including red blood cells, white blood cells, and platelets.
  • Hemolytic Anemia: This type of anemia is caused by a condition in the body that causes the destruction of RBCs before the end of their regular lifespan and the inability of the bone marrow to quickly produce RBCs to replace those that are destroyed. These conditions include an enlarged spleen, porphyria, infections of the urinary tract, thalassemia, vasculitis, and hemolysis.

Other Conditions that Cause Low MCHC Levels Include:

  • Treatments for cancers
  • Defects in the bone marrow
  • Gastrointestinal tumors
  • Kidney and liver diseases
  • Any inflammatory disorders affecting the body

Kidney diseases are characterized by the low production of erythropoietin, the hormone that signals the production of red blood cells by the bone marrow and thus causes anemia. Also, cancer treatments such as chemotherapy sometimes affect the production of new RBCs, thus resulting in anemia and low MCHC blood test results.

Symptoms of Low MCHC

As discussed earlier low MCHC results indicate anemia, a condition characterized by low hemoglobin concentration in the blood. The normal hemoglobin level in men is considered to be around 13.5 mg/dL, and in women it is 12mg/dL. If the hemoglobin levels are lesser than normal, a person is considered to be anemic.

There are no significant symptoms when the hemoglobin levels are slightly lesser than normal. But if the hemoglobin levels drop substantially, symptoms of anemia become more apparent, and they include:

  • Prolonged weakness and fatigue
  • Shortness of breath or difficulty in breathing
  • Pallor of skin and gums
  • Increased heartbeat rate or irregular heartbeat
  • Cold hands and feet
  • Frequent episodes of dizziness and headache
  • Loss of concentration
  • Chest pain

Causes of High MCHC

An MCHC blood test result showing a value higher than 36 mg/dL is considered abnormal. It is usually caused by a condition called Macrocytic Anemia or Spherocytosis.

Macrocytic anemia is a type of blood disorder caused by the failure of the body to produce enough red blood cells. It is characterized by the production of larger than normal red blood cells, called spherocytes in the body which carries more hemoglobin than normal-sized RBCs, thus causing higher MCHC levels. This condition is usually caused by a deficiency of Vitamin B12 or folic acid in the diet or the failure of the body to absorb these nutrients from the diet.

Other possible causes for high MCHC blood test results include other forms of anemia, thyroid dysfunction, treatment for cancer including chemotherapy, infections caused by certain infective agents, certain forms of leukemia, an overdose of estrogen-containing medications, or hereditary spherocytosis.

High MCHC Symptoms

As mentioned earlier, high MCHC blood test results are mostly caused by macrocytic anemia and the symptoms of this disorder are as follows:

  • Unexplained feelings and signs of fatigue and weakness
  • Palpitations of the heart
  • Pallor of skin
  • Complications in the heart health

Since macrocytic anemia has a direct bearing on heart health, early diagnosis of the condition is very important, and the doctor will determine the line of treatment for the disorder depending on the causes for it. The treatment for macrocytic anemia usually involves the prescription of Vitamin B12 and folic acid supplements. If severe malabsorption of these nutrients is found to be the cause of macrocytic anemia, the doctors may order the parenteral administration of these vitamins.

Medically Reviewed By
Dr. Kaushal M. Bhavsar (MBBS, MD)Assistant Professor in Pulmonary Medicine, GMERS Medical College, Ahmedabad