MCHC (Mean corpuscular hemoglobin concentration, Mean cell hemoglobin concentration, Mean corpuscular haemoglobin concentration, MCHC blood test, Hemoglobin concentration per red blood cell)

How to read your result

Reading MCHC starts with the reference range — typically 32 to 36 g/dL for adults — and then, immediately, with the rest of the CBC. A low MCHC (hypochromia) most often travels with small red cells and points toward iron deficiency or thalassemia trait; the lower it goes, the more established the process usually is, and values far below 30 usually mean an advanced anemia that deserves prompt attention. But MCHC almost never diagnoses anything alone: iron studies, MCV, and your history do the heavy lifting.

High MCHC works differently. Because a red cell can only physically hold so much hemoglobin, values much above 36–37 g/dL are biologically suspect. The first explanation to rule out is a measurement artifact — cold agglutinins, fatty blood, or hemolysis in the tube. Genuinely high values usually mean the red cells are abnormally round and dense, as in hereditary spherocytosis, or are being destroyed, as in autoimmune hemolytic anemia. So the practical rule of thumb: a low MCHC prompts a search for the cause; a high MCHC prompts, first, a repeat test.

What can shift this value

• Iron intake and iron stores — the single biggest driver of a low MCHC
• Blood loss, including heavy menstrual periods, gastrointestinal bleeding, and frequent blood donation
• Inherited red-cell conditions — thalassemia trait lowers MCHC, hereditary spherocytosis raises it
• Pregnancy, which sharply raises iron demand — if iron stores run down, MCHC can drift lower
• High blood fats (lipemia) after a fatty meal or with elevated triglycerides, which can falsely raise the result
• Cold agglutinins — antibodies that clump red cells in cooler temperatures and produce a falsely high reading
• Sample handling — red cells that rupture in the collection tube falsely raise MCHC
• Delays between blood draw and analysis — red cells swell in stored samples, which can falsely lower the calculated MCHC
• Chronic inflammation or long-term illness, which can gradually lower it
• Analyzer and lab differences — because MCHC is calculated, small systematic differences between laboratories are normal

When it's tested

MCHC is included in every complete blood count (CBC), where it appears among the red blood cell indices next to MCV, MCH, and RDW. That means you'll see it whenever a CBC is ordered: routine annual physicals, anemia workups, pre-surgical testing, pregnancy care, and monitoring of chronic conditions or medications that affect blood counts. It is not part of a comprehensive metabolic panel (CMP) or a lipid panel — if your printout lacks an MCHC, you likely didn't have a CBC drawn.

US labs report MCHC in g/dL; to convert to the g/L used in many other countries, multiply by 10 — so {value} {unit} is the same as {si_value} {si_unit}.