Calculate MCV, MCH, and MCHC from CBC values, classify anemia as microcytic/normocytic/macrocytic, compute Mentzer index for thalassemia screening, and assess reticulocyte production index.
Red blood cell indices — MCV (Mean Corpuscular Volume), MCH (Mean Corpuscular Hemoglobin), and MCHC (Mean Corpuscular Hemoglobin Concentration) — are calculated from the basic complete blood count (CBC) parameters and provide the fundamental framework for classifying and diagnosing anemias. These indices transform raw CBC data into clinically actionable categories that guide differential diagnosis.
This calculator computes all three RBC indices from hemoglobin, hematocrit, and RBC count, classifies the anemia morphologically (microcytic/normocytic/macrocytic and hypochromic/normochromic/hyperchromic), calculates the Mentzer index for differentiating iron deficiency from thalassemia trait in microcytic anemias, and computes the corrected reticulocyte count and Reticulocyte Production Index (RPI) to assess bone marrow response adequacy.
The morphological classification of anemia by MCV is the single most important first step in the diagnostic workup: microcytic anemias (MCV <80 fL) point toward iron deficiency, thalassemia, or chronic disease; normocytic anemias (80–100 fL) suggest acute blood loss, chronic disease, or bone marrow failure; and macrocytic anemias (MCV >100 fL) indicate B12/folate deficiency, liver disease, hypothyroidism, or myelodysplastic syndromes. Combining MCV classification with reticulocyte assessment distinguishes production disorders from destruction/loss.
This calculator computes all three RBC indices from basic CBC data, provides morphological anemia classification, calculates the Mentzer index for microcytic anemia differential diagnosis, and computes the Reticulocyte Production Index to assess marrow response — the complete first-line anemia evaluation toolkit. Keep these notes focused on your operational context. Tie the context to the calculator’s intended domain.
MCV = (Hct% / RBC) × 10 fL. MCH = (Hb / RBC) × 10 pg. MCHC = (Hb / Hct) × 100 g/dL. Mentzer Index = MCV / RBC (<13 favors thalassemia, >13 favors iron deficiency). Corrected Retic = Retic% × (Hct/45). RPI = Corrected Retic / Maturation Factor.
Result: MCV 71.4 fL (microcytic), MCH 22.6 pg, MCHC 31.7 g/dL (hypochromic), Mentzer 17.0 → iron deficiency
Low MCV (71.4) indicates microcytic anemia. Low MCHC (31.7) confirms hypochromia. Mentzer index 17.0 (>13) favors iron deficiency over thalassemia. Low RPI would confirm inadequate marrow response consistent with iron deficiency.
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MCV measures the average red blood cell volume in femtoliters (fL). Low MCV (<80 fL) means small cells (microcytic), normal (80-100) means normal-sized, and high (>100) means large cells (macrocytic). It is the primary index for classifying anemias.
The Mentzer index (MCV ÷ RBC count) helps distinguish iron deficiency from thalassemia trait in microcytic anemia. Values <13 suggest thalassemia trait (many small cells), while >13 suggests iron deficiency (fewer normal-sized or small cells). Sensitivity is ~80%.
MCHC >36 g/dL suggests hereditary spherocytosis (densely packed spherical RBCs), dehydrated cells, or laboratory artifact. True hyperchromia is uncommon and warrants peripheral smear review.
RPI corrects the reticulocyte count for both anemia severity and reticulocyte maturation time. An RPI ≥2 in an anemic patient indicates adequate marrow response (hemolysis or blood loss). RPI <2 indicates hypoproliferation (iron/B12 deficiency, marrow suppression).
Yes. Combined iron and B12/folate deficiency can produce a normal MCV because the opposing effects (microcytosis + macrocytosis) cancel out. RDW will be elevated (anisocytosis), and peripheral smear will show a dimorphic picture.
RDW measures RBC size variation (anisocytosis). Elevated RDW (>14.5%) with microcytic anemia strongly suggests iron deficiency over thalassemia trait (which typically has normal RDW). RDW is also elevated in mixed deficiencies and myelodysplastic syndromes.