What does a CBC showing mild anemia with hemoglobin of 11.5 g/dL, hematocrit of 34.7%, and normocytic indices indicate?

CBC Interpretation: Mild Normocytic Anemia

This CBC shows mild normocytic anemia with a hemoglobin of 11.5 g/dL in the context of normal white blood cell and platelet counts, requiring evaluation for underlying causes including iron deficiency, chronic disease, or occult blood loss. 1, 2

Severity Classification

• Mild anemia is present, defined as Hb ≤11.9 g/dL and ≥10.0 g/dL 1, 2
• The hemoglobin of 11.5 g/dL falls below the WHO threshold for anemia in women (Hb <12.0 g/dL) and men (Hb <13.0 g/dL) 3
• This level warrants investigation, as any degree of anemia may indicate significant underlying pathology 2

Morphologic Classification

The anemia is normocytic based on the MCV of 96.7 fL (normal range 80-100 fL): 1

• Normocytic anemia suggests causes including hemorrhage, hemolysis, bone marrow failure, anemia of chronic inflammation, or renal insufficiency 1
• The normal MCH (32) and MCHC (33.1) confirm normochromic characteristics 1
• RDW of 14% (normal range) indicates relatively uniform red cell size, making mixed deficiencies less likely 4

Other Cell Lines Assessment

All other cell lines are normal, suggesting isolated red cell pathology: 1

• WBC 7.05 (normal) rules out pancytopenia or bone marrow failure affecting multiple lineages 1
• Platelet count 413 (normal to slightly elevated) excludes thrombocytopenia 1
• Normal MPV (9.8) indicates normal platelet production 4
• Abnormalities in two or more cell lines would warrant hematology consultation 1

Required Next Steps for Evaluation

The following tests are essential to determine the cause: 1

1. Iron studies (serum iron, transferrin saturation, ferritin) - iron deficiency is the most common correctable cause even with normal MCV 1, 5
2. Reticulocyte count - to assess bone marrow response and distinguish between decreased production versus increased destruction/loss 1
3. Comprehensive metabolic panel including creatinine to evaluate for chronic kidney disease 1
4. Inflammatory markers (CRP, ESR) to assess for anemia of chronic disease 1
5. Vitamin B12 and folate levels 1
6. Thyroid function tests 1
7. Assessment for occult blood loss in stool, particularly if iron deficiency is found 1

Critical Pitfall to Avoid

Do not assume normal iron status based solely on normocytic indices - iron-depleted individuals can have normal hemoglobin, hematocrit, MCV, and MCHC while showing reduced serum iron and ferritin 5. Many cases of iron deficiency are missed when CBC alone is ordered without iron studies 5. The morphologic changes (microcytosis) occur only in severe, late-stage iron deficiency 5.

Clinical Context Considerations

Symptoms requiring assessment include: 1, 2

• Fatigue disproportionate to activity level (not relieved by rest in chronic disease) 1
• Exercise dyspnea, chest pain, or palpitations (especially concerning if cardiovascular disease present) 1
• Syncope, headache, or vertigo 1
• Signs of underlying causes: jaundice (hemolysis), pallor, blood in stool, petechiae, or heart murmur 1

Patients with cardiovascular comorbidities may experience worse symptoms at this hemoglobin level and require more aggressive evaluation and management 1, 2.