What does it mean to have elevated WBC and RBC counts with low MCV, MCH, and MCHC values in a CBC result?

CBC Analysis and Interpretation

This CBC shows mild leukocytosis with microcytic, hypochromic anemia, most likely representing iron deficiency anemia with a concurrent inflammatory or infectious process. 1

CBC Breakdown and Interpretation

Abnormal Values:

• WBC: 11.0 (H) - Mild leukocytosis
• RBC: 5.50 (H) - Elevated red blood cell count
• MCH: 24.7 (L) - Low mean corpuscular hemoglobin
• MCHC: 30.0 (L) - Low mean corpuscular hemoglobin concentration
• MCV: 83 - Low-normal (borderline microcytic)

Normal Values:

• Hemoglobin: 13.6 - Within normal range
• Hematocrit: 45.4 - Within normal range

Diagnostic Significance

Microcytic, Hypochromic Pattern

The combination of low MCH, low MCHC, and borderline low-normal MCV indicates a microcytic, hypochromic anemia pattern 1. This is most consistent with:

1. Iron deficiency anemia - The most common cause of microcytic, hypochromic anemia
2. Thalassemia minor - Another possibility, especially with elevated RBC count
3. Anemia of chronic disease - Less likely given the normal hemoglobin

The elevated RBC count with normal hemoglobin suggests a compensatory response to maintain oxygen-carrying capacity despite smaller, less hemoglobin-rich red cells 1.

Leukocytosis

The elevated WBC count (11.0 × 10³/μL) indicates mild leukocytosis, which could be due to:

1. Infection - Bacterial infections commonly cause neutrophilic leukocytosis 2
2. Inflammation - Chronic inflammatory conditions can elevate WBC counts
3. Physiologic stress - Exercise, emotional stress, or pain can cause transient leukocytosis 2
4. Medication effect - Corticosteroids, epinephrine, or lithium can increase WBC count 2

Recommended Follow-up

Additional Testing

1. Complete WBC differential - To determine which cell line is elevated (neutrophils, lymphocytes, etc.) 2
2. Iron studies - Serum ferritin, iron, TIBC, and transferrin saturation to confirm iron deficiency 1
3. Peripheral blood smear - To evaluate red cell morphology and confirm the presence of hypochromia, microcytosis, or other abnormalities 1, 3
4. Reticulocyte count - To assess bone marrow response to anemia 1
5. Hemoglobin electrophoresis - If thalassemia is suspected, especially with elevated RBC count 1

Clinical Correlation

1. Evaluate for sources of blood loss - Especially gastrointestinal bleeding in adults
2. Assess for symptoms of infection - Fever, localized pain, or other signs of infection 2
3. Review medication list - For drugs that can cause leukocytosis 2
4. Dietary history - To assess iron intake, especially in women of reproductive age

Common Pitfalls to Avoid

1. Ignoring elevated RBC count - This can be a compensatory mechanism in early iron deficiency or a clue to thalassemia 1
2. Attributing leukocytosis solely to infection - Multiple non-infectious causes exist, including stress, medications, and inflammatory conditions 2
3. Failing to consider pre-analytical variables - Sample storage time and temperature can affect CBC results 4
4. Overlooking borderline values - An MCV of 83 is at the lower end of normal and may represent early microcytosis 1
5. Missing combined disorders - Iron deficiency can coexist with other conditions like infection or inflammation 1

This CBC pattern warrants further investigation to determine the underlying cause of both the microcytic, hypochromic anemia pattern and the leukocytosis, as these may represent separate or related pathological processes.