Mild Anemia with Elevated RDW: Likely Iron Deficiency Requiring Confirmation
These results show mild anemia (hemoglobin 11.6 g/dL, hematocrit 35.4%) with an elevated red cell distribution width (RDW 15.8%) and elevated mean platelet volume (MPV 13.1 fL), which strongly suggests early iron deficiency anemia that requires immediate iron studies for confirmation.
Key Findings Interpretation
Anemia Present
- Your hemoglobin is 11.6 g/dL, which falls below the laboratory's lower limit of normal (11.7 g/dL) and meets criteria for anemia 1
- The hematocrit of 35.4% is similarly just below normal (35.9%)
- This is mild anemia that warrants investigation, particularly when iron deficiency is suspected 1
Red Cell Indices Pattern
The pattern of your red cell indices is particularly informative:
- MCV (82.7 fL), MCH (27.1 pg), and MCHC (32.8 g/dL) are all at the lower end of normal - this represents borderline normocytic anemia that may be transitioning toward microcytic anemia
- RDW is elevated at 15.8% (normal up to 15.0%) - this indicates increased variation in red blood cell sizes (anisocytosis)
This combination—mild anemia with normal-to-low MCV and elevated RDW—is the classic early signature of iron deficiency anemia 1. The RDW rises before MCV drops because the body produces increasingly variable red cell sizes as iron stores become depleted.
Platelet Findings
- MPV is mildly elevated at 13.1 fL (normal up to 12.5 fL)
- This can occur with iron deficiency and represents increased platelet turnover 2
- Platelet count itself is normal at 191,000/μL
Immediate Next Steps
You must obtain iron studies immediately to confirm iron deficiency 1. The essential tests are:
Serum ferritin (most important single test):
- <15 μg/L = definite iron deficiency
- <30 μg/L = likely depleted iron stores
- <45 μg/L = consider iron deficiency, especially with inflammation
150 μg/L = iron deficiency unlikely even with inflammation 1
Transferrin saturation - helpful if ferritin results are equivocal 1
Consider inflammatory markers (CRP, ESR) - ferritin can be falsely normal with concurrent inflammation since it's an acute phase reactant 1
Clinical Pitfalls to Avoid
- Do not assume this is "just borderline normal" - the elevated RDW with borderline-low hemoglobin and MCH strongly suggests evolving iron deficiency 1
- Do not wait for MCV to drop - MCH and RDW changes precede microcytosis in iron deficiency 1
- If ferritin is 30-100 μg/L with inflammation present, iron deficiency can still exist; consider transferrin saturation or a therapeutic trial of iron 1
Investigation for Underlying Cause
Once iron deficiency is confirmed, investigation should be considered at any level of anemia in the presence of iron deficiency, as the likelihood of serious underlying gastrointestinal pathology increases with severity 1. The investigation intensity depends on:
- Patient sex and menstrual status (menstruating women have an obvious potential source)
- Degree of anemia (more severe = higher priority for GI investigation)
- Presence of GI symptoms (any red flag symptoms warrant urgent evaluation)
- Age and risk factors for GI malignancy
Therapeutic Confirmation
If iron studies confirm deficiency, a hemoglobin rise of ≥10 g/L within 2 weeks of starting iron therapy is highly suggestive of absolute iron deficiency, even if initial iron studies were equivocal 1. This therapeutic trial can serve as both diagnostic confirmation and treatment.
Summary of Your Results
- ✓ White blood cells: Normal
- ✓ Red blood cell count: Normal
- ⚠️ Hemoglobin: Low (mild anemia)
- ⚠️ Hematocrit: Low
- ✓ MCV, MCH, MCHC: Borderline low-normal
- ⚠️ RDW: Elevated (suggests early iron deficiency)
- ✓ Platelets: Normal count
- ⚠️ MPV: Mildly elevated (consistent with iron deficiency)
The pattern strongly suggests early iron deficiency anemia. Order iron studies now.