MCHC · high result
High MCHC: what it means, artifact versus spherocytosis and what to check next
Short answer
A high MCHC — red cells unusually concentrated with hemoglobin, above about 36 g/dL — is uncommon and most often a sample artifact: high lipids, cold agglutinins, hemolysis in the tube or a very high white count fool the analyzer. When it is real, it points to hereditary spherocytosis, autoimmune hemolysis with spherocytes, sickle or hemoglobin C disease, severe burns or dehydration of the cells by a high sodium. The first step is a repeat on a fresh, warmed sample; the second is a blood film.
Medically reviewed by Youmna DiStefano, MD · Last reviewed November 2026
When does this result need same-day care?
- A high MCHC with jaundice, dark urine, fever or a rapidly falling hemoglobin — acute hemolysis; same-day care
- Severe pain, chest symptoms or breathlessness in someone with a known sickle cell disorder — emergency care
What is the normal range for MCHC?
- age 18+: 32 – 36 g/dL
Full reference table, citations and testing options: MCHC biomarker page.
What are the common causes of high MCHC?
- Sample artifact — lipemic plasma, cold agglutinins (cells clump in the cold), hemolysis in the tube, a very high white count, icterus or an abnormal paraprotein; the analyzer measures too much hemoglobin for the cell volume
- Hereditary spherocytosis — red cells lose membrane and become dense spheres; an MCHC above 35–36 g/dL with a raised RDW is the classic screening clue
- Autoimmune hemolytic anemia with spherocytes, and other hemolytic anemias
- Sickle cell disease (especially hemoglobin SC) and hemoglobin C disease — dehydrated, dense cells
- Severe burns and hereditary xerocytosis
- Hypernatremia — a high plasma sodium draws water out of the cells
- Recent transfusion of stored red cells, and some analyzer calibration issues — most laboratories flag any MCHC above 37 g/dL for review
What symptoms go with high MCHC?
- None from the MCHC itself — a high value is usually noticed on a routine CBC
- Jaundice, dark urine, fatigue and an enlarged spleen when hemolysis is the cause
- Gallstones and episodes of anemia with viral illness in hereditary spherocytosis, often with a family history
- Bone pain, episodes of severe pain and anemia in sickle cell disorders
What do clinicians usually check next?
- Repeat the CBC on a fresh sample, kept and run at 37 °C if cold agglutinins are suspected, with the plasma checked for lipemia — most high values disappear
- A peripheral blood film for spherocytes, sickle cells, target cells or clumping
- Reticulocyte count, LDH, indirect bilirubin and haptoglobin for hemolysis; a direct antiglobulin (Coombs) test when hemolysis is confirmed
- An EMA-binding test or osmotic fragility test for hereditary spherocytosis; hemoglobin electrophoresis for sickle and hemoglobin C disorders
- Serum sodium and a lipid panel when the artifact causes are being excluded
- Hematology referral when hemolysis is confirmed or a persistent true MCHC above 36 g/dL has no explanation
Follow-up tests available at TestWell: Lipid Panel ($19.99), LDH Test (Lactate Dehydrogenase) ($19.99), Haptoglobin Test ($101.99).
How do you recheck MCHC?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Biological Age Panel | Panel · 3 tests | $59.99 | Yes | 1–3 business days |
| General Wellness Panel | Panel · 4 tests | $49.99 | Yes | 1–3 business days |
| Blood Clotting Panel | Panel · 4 tests | $149.99 | No | 3–7 business days |
| CBC with Differential Test | Test · 15 biomarkers | $17.99 | No | 1–3 business days |
Common questions
What does high MCHC mean?
Most often, that the sample fooled the analyzer — high lipids, cold agglutinins, hemolysis in the tube or a very high white count make the hemoglobin read too high for the cell volume. A genuinely high MCHC means dense, dehydrated red cells, as in hereditary spherocytosis, autoimmune hemolysis, sickle or hemoglobin C disease, severe burns or a high sodium. A fresh repeat and a blood film sort it out.
Can MCHC be falsely high?
Yes, and it usually is. Lipemic plasma, cold agglutinins, in-tube hemolysis, icterus and a high white count all raise the measured hemoglobin or lower the measured volume. Laboratories flag an MCHC above about 37 g/dL for review and often rerun the sample warmed or with the plasma replaced before reporting it.
What MCHC level is too high?
Above about 36 g/dL on most ranges; the physiological ceiling is around 37, because red cells cannot pack hemoglobin more densely, so values above that are artifacts until proven otherwise. A persistent 35–36.5 g/dL with a raised RDW and any sign of hemolysis is the pattern that prompts testing for hereditary spherocytosis.
Is a high MCHC dangerous?
The number itself is not. The conditions that genuinely raise it — hereditary spherocytosis, hemolytic anemia, sickle cell disorders — matter and are diagnosed with a blood film, hemolysis markers and specific tests. A high MCHC that disappears on a fresh, warmed sample needs nothing further.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.