# Low or High MCHC in Cats: Bloodwork Explained MCHC on a cat bloodwork panel measures how much hemoglobin is packed into each red blood cell. A low or high MCHC by itself does not diagnose a disease, but it helps your veterinarian sort out whether your cat has anemia and what kind. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - MCHC stands for mean corpuscular hemoglobin concentration. It is a calculated value on the CBC (complete blood count), not a separate test. - A low MCHC usually means the red blood cells are underfilled with hemoglobin, which often points to iron deficiency or a problem with how hemoglobin is made. - A high MCHC is often an artifact. It commonly appears when red blood cells clump together, when the sample is hemolyzed, or when the analyzer misreads the cells. - MCHC is read alongside the hematocrit, hemoglobin, MCV, and reticulocyte count. One number in isolation rarely tells the whole story. - Any anemia in a cat deserves a veterinary workup. Cats hide illness well, and anemia is almost always a sign of an underlying problem. ## What MCHC Looks Like on Cat Bloodwork MCHC is one line on a CBC report. You will usually see it printed next to MCV (mean corpuscular volume, the average size of the red cells) and MCH (mean corpuscular hemoglobin, the average amount of hemoglobin per cell). The main job of red blood cells is to carry oxygen to tissues. Oxygen rides inside the red cell attached to hemoglobin. Red cells are made in the bone marrow from stem cells, and in a healthy cat the number of red cells stays steady because new cells replace old ones [1]. MCHC describes how concentrated the hemoglobin is inside those cells. ### What Is a Normal MCHC in Cats? Reference ranges vary by laboratory, so always compare your cat's result to the range printed on your own report. In general, feline MCHC runs roughly in the low-to-mid 30s in grams per deciliter (g/dL), and most labs flag anything outside their own range. Two things matter more than the exact number: - The trend over time. A value that drifts across several visits means more than one slightly odd result. - The rest of the panel. MCHC only makes sense next to the hematocrit, hemoglobin, MCV, and reticulocyte count. ### What Owners Actually Notice MCHC itself causes no symptoms. What you may notice is the anemia behind it. Signs include pale gums, lethargy, weakness, fast breathing, a fast heart rate, and reduced appetite. Some cats with anemia simply seem "off" or sleep more. If your cat's gums look white, gray, or blue instead of pink, that is a reason to call your veterinarian right away. ## Causes of Low MCHC in Cats A low MCHC means the red cells are hypochromic, or pale, because they carry less hemoglobin than normal. This usually develops alongside a low MCV (microcytosis), meaning the cells are also small. Iron deficiency is the classic cause. One report of a cat with chronic lymphocytic leukemia described a moderate, microcytic anemia with confirmed iron deficiency [2]. Iron is needed to build hemoglobin, so when iron runs short, the cells come out small and pale. Chronic blood loss is a common route to iron deficiency. Slow bleeding from the gut, a bleeding mass, or heavy parasite burdens can drain iron over weeks. You may see no blood at all, just a gradual decline in energy. Long-standing inflammation or chronic kidney disease can also blunt red cell production. Cats on continuous renal replacement therapy for severe kidney injury showed a progressive drop in hematocrit despite transfusions, which shows how fragile red cell balance becomes in very sick cats [3]. ## Causes of High MCHC in Cats A high MCHC is trickier because it is frequently a lab artifact instead of a real finding. The most common cause is red blood cell clumping, called agglutination. When cells stick together, the analyzer counts a clump as one large cell and misreads the hemoglobin, pushing MCHC up. Agglutination is a real clinical clue, though. It appears in immune-mediated hemolytic anemia, where the immune system destroys red cells. In cats with feline infectious peritonitis and associated immune-mediated hemolytic anemia, a positive saline agglutination test or Coombs test helped confirm the diagnosis [4]. Other causes of a falsely high MCHC include a hemolyzed sample, lipemia (fat in the blood), icterus (yellow discoloration from bilirubin), and analyzer interference. A hand-held hemoglobinometer study in cats specifically examined how anemia, leukocytosis, azotemia, lipemia, icterus, and hemolysis affect readings, which shows how much these variables can matter [5]. True high MCHC is uncommon. When it appears with a high MCV and signs of hemolysis, your veterinarian will look hard for immune-mediated destruction. ## MCHC and Anemia: Putting the Numbers Together Anemia means the hematocrit or hemoglobin is below the reference range. MCHC helps classify it. | Pattern | What it suggests | Typical clues | How urgent | |---|---|---|---| | Low MCHC, low MCV | Iron deficiency, chronic blood loss | Small pale cells, slow onset, low iron | Same-week visit, sooner if weak | | Low MCHC, normal MCV | Early iron deficiency, inflammation, chronic disease | Mild anemia, underlying illness | Routine to same-week visit | | High MCHC with agglutination | Immune-mediated hemolytic anemia | Pale or yellow gums, rapid onset, clumped cells | Emergency | | High MCHC without agglutination | Lab artifact, hemolysis, lipemia, icterus | Sample quality issue, repeat draw needed | Routine repeat test | | Normal MCHC with anemia | Many causes, including non-regenerative disease | Depends on reticulocyte count | Depends on severity | Cats with immune-mediated hemolytic anemia can be severely affected. In one study of 37 cats with non-associative IMHA, overall mortality was 24.3 percent, and all deaths occurred within four weeks [6]. In cats with FIP-associated IMHA, the median hematocrit at diagnosis was 18 percent, and anemia was non-regenerative in 80 percent of them [4]. These numbers show why anemia in cats is taken seriously. MCHC has also been studied as a prognostic marker in other feline diseases. In cats with mammary carcinoma, MCHC and platelet count remained independent prognostic factors for overall survival in multivariate analysis [7]. That does not mean MCHC causes cancer. It means the value can reflect how sick a cat is overall. If your cat's panel also shows changes in kidney values, see [Understanding Cat Blood Tests: Interpreting Renal Markers BUN, Creatinine and SDMA](/knowledge/veterinary-medicine/at-home-diagnostics/understanding-cat-blood-tests-interpreting-renal-markers-bun-creatinine-and-sdma). If liver values are flagged too, [Liver Enzyme Interpretation in Dogs and Cats: Beyond the Numbers](/knowledge/veterinary-medicine/clinical-pathology/liver-enzyme-interpretation-dogs-cats) explains what those numbers mean. ## Red Flags That Make This an Emergency Call an emergency clinic now if your cat has any of these: - Gums that are white, gray, or blue - Labored breathing or breathing with the mouth open - Collapse, extreme weakness, or inability to stand - A heart rate that feels very fast or irregular - Sudden yellow color to the gums, skin, or whites of the eyes - Known anemia plus any new lethargy or refusal to eat Severe anemia can worsen quickly. Cats with IMHA can deteriorate within days, and most deaths in one study happened in the first four weeks after diagnosis [6]. Do not wait for a scheduled appointment if your cat looks acutely unwell. ## What You Can Safely Do at Home While Waiting You cannot fix MCHC at home, and you should not try. Focus on keeping your cat stable and comfortable until the visit. - Keep your cat indoors and quiet. Activity increases oxygen demand, which a cat with anemia cannot meet. - Offer water freely and small amounts of a familiar food. Do not force feeding. - Check gum color once or twice a day in good light. Note any change. - Collect any information your veterinarian may want, such as appetite changes, weight loss, vomiting, diarrhea, or black tarry stool. - Do not give iron supplements, vitamins, or any human medication. Iron overdose is toxic to cats, and dosing is not something you can guess. If your cat is on medication for a chronic condition, keep giving it unless your veterinarian says otherwise. ## What Your Veterinarian Will Check and Test Your veterinarian will start with a physical exam, including gum color, hydration, heart rate, and a check for enlarged lymph nodes or an enlarged spleen or liver. Then they will review the CBC in detail. Key questions include: - Is the cat truly anemic, based on hematocrit and hemoglobin? - Is the anemia regenerative? The reticulocyte count tells whether the bone marrow is responding. - Are the cells small (low MCV) or large (high MCV)? - Is there agglutination on the blood film? Follow-up testing often includes a blood film review, a saline agglutination test, a Coombs test, iron studies, and a biochemical panel. Imaging such as abdominal ultrasound may be used to look for masses, bleeding, or organ changes. In one leukemia case, the workup combined blood film review, iron analysis, ultrasound, flow cytometry, protein electrophoresis, and a PCR test to reach a diagnosis [2]. If immune-mediated hemolysis is suspected, treatment usually starts with glucocorticoids, and cyclosporin A is often added [6]. Cats with severe anemia may need a transfusion. For more on that process, see [Blood Transfusion in Dogs and Cats: Crossmatching and Compatibility](/knowledge/veterinary-medicine/emergency-critical-care/blood-transfusion-dogs-cats-crossmatching-compatibility). Because anemia and thyroid disease can overlap in older cats, [Thyroid Testing in Cats: Diagnosing Hyperthyroidism and T4 Fluctuations](/knowledge/veterinary-medicine/at-home-diagnostics/thyroid-testing-in-cats-diagnosing-hyperthyroidism-and-t4-fluctuations) is a useful companion read. ## Prevention and Monitoring You cannot prevent every cause of abnormal MCHC, but you can catch problems earlier. - Keep routine wellness visits, especially for cats over 8 years old. A CBC at each visit builds a trend line. - Use year-round parasite prevention as your veterinarian recommends. Gut parasites can contribute to iron loss. - Watch for subtle weight loss. It is one of the earliest signs of many feline diseases. - If your cat has a chronic illness, follow the recheck schedule. Trends matter more than single results. - Ask for a copy of every lab report. Keep them together so you can see how values move over time. If your cat has cancer, kidney disease, or immune disease, MCHC may be tracked as one of several markers. In cats with mammary carcinoma, MCHC and platelet count were independent prognostic factors for survival, which is one reason veterinarians follow these values over time [7]. ## Limitations and When to Contact a Veterinarian MCHC is a calculated value, and it is easily distorted by clumping, hemolysis, and other sample problems [5]. A single abnormal MCHC does not confirm any diagnosis. It is a clue that points your veterinarian toward more specific testing. Contact your veterinarian the same day if you notice pale gums, new lethargy, or a drop in appetite. Go to an emergency clinic immediately if your cat is breathing hard, has collapsed, or has blue or white gums. Schedule a routine visit if an abnormal MCHC appeared on a screening panel and your cat seems well. Every cat is different. Your veterinarian needs to examine your cat and review the full panel to decide what your cat's MCHC means and what testing comes next. ## Frequently Asked Questions ### Does a low MCHC always mean my cat is anemic? No. MCHC can dip slightly without the hematocrit or hemoglobin falling below range. When true anemia is present, a low MCHC usually points toward iron deficiency or a problem with hemoglobin production. Your veterinarian will confirm by looking at the whole CBC and the blood film. ### Can a high MCHC be a lab error? Yes, and that is the most common explanation. Red cell clumping, hemolysis, lipemia, and icterus can all push the number up falsely [5]. Your veterinarian may simply repeat the sample or review the blood film before drawing conclusions. ### Is MCHC the same as hemoglobin? No. Hemoglobin is the actual amount of oxygen-carrying protein measured in your cat's blood. MCHC is a calculated average of how concentrated that hemoglobin is inside each red cell. Both appear on the same report but they answer different questions. ### Will my cat need a transfusion for abnormal MCHC? Not usually. Transfusions are reserved for severe or symptomatic anemia, not for an MCHC value alone. Your veterinarian decides based on the hematocrit, your cat's clinical signs, and how quickly the anemia developed. ### How often should MCHC be rechecked? That depends on why it was abnormal. A suspected lab artifact may be rechecked within days. A chronic condition may be monitored every few weeks to months. Your veterinarian will set the schedule based on your cat's diagnosis and response to treatment. ## Related Articles - [Understanding Cat Blood Tests: Interpreting Renal Markers BUN, Creatinine and SDMA](/knowledge/veterinary-medicine/at-home-diagnostics/understanding-cat-blood-tests-interpreting-renal-markers-bun-creatinine-and-sdma) - [Liver Enzyme Interpretation in Dogs and Cats: Beyond the Numbers](/knowledge/veterinary-medicine/clinical-pathology/liver-enzyme-interpretation-dogs-cats) - [Blood Transfusion in Dogs and Cats: Crossmatching and Compatibility](/knowledge/veterinary-medicine/emergency-critical-care/blood-transfusion-dogs-cats-crossmatching-compatibility) - [Thyroid Testing in Cats: Diagnosing Hyperthyroidism and T4 Fluctuations](/knowledge/veterinary-medicine/at-home-diagnostics/thyroid-testing-in-cats-diagnosing-hyperthyroidism-and-t4-fluctuations) - [Lymphoma in Cats: High-Grade vs Low-Grade GI Alimentary Lymphoma](/knowledge/veterinary-medicine/dermatology-oncology/lymphoma-in-cats-high-grade-vs-low-grade-gi-alimentary-lymphoma) - [Cat Diabetes: How to Tell If Your Cat's Insulin Dose Is Too Low](/knowledge/veterinary-medicine/senior-and-chronic-care/cat-diabetes-insulin-underdose-signs) ## References 1. [Red Blood Cells of Cats - Cat Owners](https://www.merckvetmanual.com/cat-owners/blood-disorders-of-cats/red-blood-cells-of-cats). Merck Veterinary Manual. 2. [B-Cell Chronic Lymphocytic Leukemia in a Cat](https://pubmed.ncbi.nlm.nih.gov/41540818/). Veterinary clinical pathology, 2025. 3. [Hematologic and Renal Trends in Cats Undergoing Continuous Renal Replacement Therapy: A Retrospective Case Series with Molidustat Use](https://pubmed.ncbi.nlm.nih.gov/42798007/). Veterinary sciences, 2026. 4. [Immune-Mediated Hemolytic Anemia in Cats with Feline Infectious Peritonitis](https://pubmed.ncbi.nlm.nih.gov/40732707/). Pathogens (Basel, Switzerland), 2025. 5. [Method Comparison and Investigation of Interference Variables of a Hand-Held Hemoglobinometer(HemoCue Hb 201+) in Cats](https://pubmed.ncbi.nlm.nih.gov/40662223/). Veterinary clinical pathology, 2025. 6. [Clinical Findings, Treatment and Long-Term Outcome in 37 Cats with Non-Associative Immune-Mediated Hemolytic Anemia: A Retrospective Observational Study of Two Treatment Cohorts](https://pubmed.ncbi.nlm.nih.gov/42738514/). Animals : an open access journal from MDPI, 2026. 7. [Platelet count and MCHC as independent prognostic markers for feline mammary carcinomas](https://pubmed.ncbi.nlm.nih.gov/37827061/). Research in veterinary science, 2023. ## Further Reading - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)