MCHC Blood Test: What High and Low Results Mean?

An MCHC blood test is a standard inclusion in a complete blood count. Healthcare providers look into the MCHC value to confirm certain diseases and deficiencies. However, interpreting the results requires evaluating the other CBC tests as well. Still, knowing what high and low MCHC results mean provides you clarity on your blood health. Read on to find out more about this test.  

What Is an MCHC Blood Test?

MCHC stands for mean corpuscular hemoglobin concentration. It is a key metric included in a complete blood count (CBC). 

An MCHC blood test measures the concentration of hemoglobin, the protein present in the red blood cells that carry oxygen, in relation to the size of the red blood cell (RBC). 

Keep in mind that the RBCs or erythrocytes make up 40% of the blood⁽¹⁾ and facilitate the distribution of oxygen in tissues. With hemoglobin playing a crucial role in this function, understanding their concentration reveals abnormalities that impede cellular respiration. 

That said, an MCHC test can be taken as part of a routine exam. But it also serves as a valuable diagnostic tool for detecting diseases such as certain types of anemia, liver disease, inflammation, and some blood disorders.  

However, the MCHC blood test is not enough for your doctor to diagnose accurately. Other tests, some of which are already included in the CBC, will be performed depending on your symptoms. 

Also Read: 5 Ways to Fix Low Red Blood Cell (RBC) Count

How the test is performed

You will need to provide a blood sample during a CBC, which already includes the MCHC test. A licensed medical technician will draw the blood, usually from your vein, and analyze the sample. Specifically, the average amount of hemoglobin in the RBCs and the blood volume will be calculated. 

For CBC, you don’t need to fast or do special preparations. Still, consult your healthcare provider for specific instructions prior to the test. This way, you can ensure accurate results. 

MCHC Blood Test Results

The CBC blood test result will indicate your MCHC along with the reference value interval. The normal MCHC is 31.5 to 35.7 g/dL. It might slightly vary depending on the lab performing the test. If your test results go outside the normal range, it could be due to specific causes, which are discussed below. 

Low MCHC Meaning

You have deficient MCHC if the value falls below 31.5 g/dL. Although it acts as a sign and not a definitive indicator, low MCHC can be associated with the following disorders:

• Iron-deficiency anemia: Iron is a crucial component of hemoglobin. Therefore,  insufficient iron in the body leads to low production of hemoglobin⁽²⁾. In some cases, even if production is a non-issue, the RBCs appear smaller and paler.   
• Thalassemia: Low MCHC is also linked to Thalassemia, which is a hereditary blood disorder that causes diminished hemoglobin production. 
• Sideroblastic anemia: This type of anemia is caused by the body’s inability to use iron to create red blood cells. Hence, hemoglobin is naturally low, leading to decreased MCHC. 
• Chronic infection: Long-term infections⁽³⁾ can impact RBC production. The same can be said with chronic inflammation and other health conditions, like kidney disease. 

A low MCHC blood test result can also be due to blood loss or a recent blood transfusion since hemoglobin is likely diluted for a short period. Simply put, any condition that interferes with RBC production can cause low MCHC. Hence, treating the underlying health problem should help improve hemoglobin concentration. 

High MCHC Meaning

Elevated MCHC occurs when your test result exceeds 35.7 g/dL. It isn’t necessarily a diagnosis in itself. However, a higher-than-normal hemoglobin concentration can be found in the following conditions. 

• Hemolytic anemia: You may get a high MCHC blood test result when your RBCs are destroyed (hemolysis) faster than they are produced — which is essentially hemolytic anemia. 
• Spherocytosis: Red blood cells are disc-shaped. But if you have spherocytosis, a genetic blood disorder, your RBCs look spherical, making them more breakable, which generates high MCHC⁽⁴⁾. 
• Liver disease: Some liver diseases cause hemolysis and macrocytosis, a condition that inflates the size of the RBCs. All these can lead to high MCHC. 

Other conditions can also indirectly contribute to elevated MCHC, like hyperthyroidism and dehydration. Nonetheless, treatment for high MCHC is specific to the underlying cause. 

Frequently Asked Questions

What is the difference between MCH and MCHC?

MCH stands for mean corpuscular hemoglobin. It’s different from MCHC (mean corpuscular hemoglobin concentration) in that it measures hemoglobin mass in a single red blood cell (RBC). In contrast, MCHC measures the density of hemoglobin against the size of the RBC. Both tests are crucial in diagnosing certain blood disorders, like thalassemia and anemia.  

What cancers cause low MCHC?

Certain cancers impact hemoglobin development or destruction, which in turn causes low MCHC. For example, cancers that interfere with bone marrow activities, such as leukemia, multiple myeloma, and lymphoma, prevent RBC production. Likewise, cancers that cause bleeding, including colon and stomach cancer, lead to the same effect. 

Can dehydration cause high MCHC?

Yes, dehydration can elevate your MCHC. When you’re dehydrated, blood plasma volume is reduced, making the blood more concentrated. RBC numbers remain the same, but the density of hemoglobin can increase. 

The Bottom Line

As MCHC is included in the CBC, you can book the test as part of your routine wellness checkup. However, healthcare providers typically underscore MCHC results together with other tests, like MCH and MCV, when diagnosing certain blood disorders, like anemia. To better understand what your MCHC blood test result says about your health, consult your doctor and note any unusual conditions or symptoms you experience. 

Sources

¹ Sharma R, Sharma S. Physiology, Blood Volume. 2023 Apr 10. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. PMID: 30252333.

² Leung AKC, Lam JM, Wong AHC, Hon KL, Li X. Iron Deficiency Anemia: An Updated Review. Curr Pediatr Rev. 2024;20(3):339-356. doi: 10.2174/1573396320666230727102042. PMID: 37497686.

³ Viana MB. Anemia and infection: a complex relationship. Rev Bras Hematol Hemoter. 2011;33(2):90-2. doi: 10.5581/1516-8484.20110024. PMID: 23284251; PMCID: PMC3520628.

⁴ Michaels LA, Cohen AR, Zhao H, Raphael RI, Manno CS. Screening for hereditary spherocytosis by use of automated erythrocyte indexes. J Pediatr. 1997 Jun;130(6):957-60. doi: 10.1016/s0022-3476(97)70283-x. PMID: 9202619.