Mean Corpuscular Hemoglobin Concentration
MCHC· also: Mean Cell Hemoglobin Concentration
Clinical Overview
MCHC measures the average concentration of hemoglobin in red blood cells as g/dL. Unlike MCH, it corrects for cell size, making it a true measure of hemoglobin packing density. MCHC is the most stable CBC index and is often used as an internal quality control measure for laboratory instruments.
Why This Test Matters
MCHC is primarily used to detect true hypochromia (low MCHC in severe iron deficiency) and to identify hereditary spherocytosis, where MCHC is paradoxically elevated because spherical cells have a smaller surface-to-volume ratio. A very high MCHC often indicates a laboratory artifact (hemolysis, lipemia) rather than a real clinical abnormality.
Reference RangesWHO/IFCC standards
| Age Group | Reference Range | Unit | Notes |
|---|---|---|---|
| Adults (18–64) | 31.5 – 36 | g/dL | — |
Also reported in: %.
What Causes Abnormal Results?
High MCHC Causes
- Hereditary spherocytosis
- Sample hemolysis (most common — artifact)
- Cold agglutinins (artifact)
- Severe lipemia (artifact)
Low MCHC Causes
- Severe iron deficiency anemia
- Thalassemia major
Signs & Symptoms to Watch For
How to Prepare for This Test
No preparation required. Calculated automatically from Hgb, RBC, and MCV.
Factors That Can Affect Results
- Sample hemolysis (falsely raises MCHC — most common cause of high MCHC)
- Lipemia (interferes with optical hemoglobin measurement)
- Cold agglutinins
Related Topics
Frequently Asked Questions
What does a high MCHC mean?
A high MCHC (above 36 g/dL) is most commonly a laboratory artifact caused by sample hemolysis or lipemia. When it is truly elevated on a repeat test, hereditary spherocytosis is the most important clinical cause to consider. The diagnosis of spherocytosis is confirmed with the EMA binding test by flow cytometry or osmotic fragility testing.