Mean Corpuscular Hemoglobin Concentration
Also written as: MCHC
How densely hemoglobin is packed into red blood cells, on average.
What it measures
The average concentration of hemoglobin packed inside red blood cells - how full each cell is, rather than how big it is. It is calculated from the hemoglobin level and the hematocrit rather than measured directly.
Why a doctor orders it
It arrives as part of every complete blood count and helps classify anemias. Laboratories also watch it closely because a strikingly unusual MCHC is one of the most reliable clues that something went wrong with the sample or the analyzer rather than with the patient.
What is generally associated with a higher result
Broadly associated with hereditary spherocytosis, an inherited condition in which red cells are small and dense. Just as often it reflects a lab artifact - a hemolyzed sample, a fatty sample, or cold-reacting antibodies - which is why an unexpected high value is commonly rechecked before anything else.
What is generally associated with a lower result
Broadly associated with pale, hemoglobin-poor red cells, most commonly from iron shortage and sometimes from inherited hemoglobin traits.
Everyday things that move this number
Not every shift in a value reflects disease. These are ordinary factors known to affect this particular measurement:
- Sample hemolysis - red cells breaking open in the tube during or after the draw
- A fatty meal before the draw, which clouds the sample
- Cold-reacting antibodies that clump cells, a lab artifact
- Time the sample spent in transport before analysis
Questions to take to your appointment
- Could this reflect a sample or analyzer artifact rather than a true result?
- Was a blood smear reviewed under the microscope to confirm what the machine reported?
- Do the other red cell indices on the panel fit with this value?
Build a printable questionnaire with your own results →
Where to read more
MedlinePlus, from the US National Library of Medicine, publishes patient-facing pages on individual lab tests and is a reliable next stop: medlineplus.gov/lab-tests .
Support this site
This site is free, has no paywall, and takes no money from hospitals, insurers, or billing companies. If it helped, a coffee keeps it going.
Buy us a coffee