What parameters should be included in a table for anemia labs?

Anemia Laboratory Panel

Essential Initial Tests

A comprehensive anemia laboratory workup should include CBC with indices, reticulocyte count, iron studies (serum ferritin, transferrin saturation, serum iron, TIBC), and inflammatory markers. 1, 2

Core Parameters

Complete Blood Count (CBC) with Indices

• Hemoglobin (Hb): Defines anemia severity; <12 g/dL in women, <13 g/dL in men 3
• Hematocrit (Hct): Confirms anemia; normal values are 41±5% for women, 47±6% for men 1
• Mean Corpuscular Volume (MCV): Classifies anemia type (microcytic <80 fL, normocytic 80-100 fL, macrocytic >100 fL) 4, 5
• Red Cell Distribution Width (RDW): Elevated RDW indicates heterogeneous red cell population and can be an early indicator of iron deficiency before MCV changes 1, 5
• Red Blood Cell Count: Helps distinguish thalassemia (elevated) from iron deficiency 3

Important caveat: MCV-guided classification alone is unreliable—16% of microcytic patients and 90% of macrocytic patients may have etiologies inconsistent with traditional MCV-based assumptions 4. Use a broader laboratory panel regardless of MCV 4.

Reticulocyte Parameters

• Reticulocyte Count: Assesses bone marrow response; distinguishes hypoproliferative from hemolytic/hemorrhagic anemia 2, 5
• Reticulocyte Hemoglobin Content (CHr): Identifies iron-restricted erythropoiesis; more readily available than soluble transferrin receptor 3, 5
• Immature Reticulocyte Fraction (IRF): Evaluates bone marrow erythropoietic activity 5

Iron Studies (Critical for All Anemia Workups)

• Serum Ferritin: Most powerful single test for iron deficiency 3, 2

  • <12-15 μg/L diagnostic of iron deficiency 3
  • <30 μg/L confirms iron deficiency without inflammation 2

  • 100 μg/L makes iron deficiency unlikely 3, 2

  • Can be falsely elevated with inflammation, malignancy, or liver disease 3, 2

• Transferrin Saturation (TSAT): <16-20% suggests iron deficiency 3, 2

• Serum Iron and Total Iron-Binding Capacity (TIBC): Interpret alongside ferritin and TSAT 2, 6

Additional Essential Tests

• C-Reactive Protein (CRP): Assesses inflammation that affects iron study interpretation 3, 1, 2
• Serum Creatinine/eGFR: Evaluates for chronic kidney disease as cause of anemia 3, 2
• Vitamin B12 and Folate: Rules out nutritional deficiencies that can mask microcytosis in mixed deficiencies 1, 2
• Thyroid Function Tests: Excludes hypothyroidism in normocytic anemia 2

Condition-Specific Additional Tests

For Microcytic Anemia

• Hemoglobin Electrophoresis: Rules out thalassemia and hemoglobinopathies, especially in appropriate ethnic backgrounds 3, 2, 7
• Stool Guaiac Test: Checks for occult gastrointestinal bleeding 2

For Chronic Kidney Disease Patients

• Serum Bicarbonate: Evaluates metabolic acidosis; monitor at least every 3 months if GFR <30 mL/min/1.73m² 2
• Calcium, Phosphorus, Intact PTH: Essential for CKD-related anemia management 2
• NT-proBNP: In heart failure patients with anemia 3

For Suspected Hemolysis

• Micro-Coombs Test: Evaluates autoimmune hemolytic anemia 8
• Peripheral Blood Smear: Identifies red cell morphology abnormalities 5, 8

Monitoring Frequency

• Hemoglobin monitoring every 3 months if GFR <30 mL/min/1.73m² in CKD patients 2
• Regular hemoglobin monitoring preferred over hematocrit due to greater accuracy and less measurement variability 1

Critical Pitfalls to Avoid

• Never assume normocytic anemia excludes iron deficiency: Early iron deficiency presents with normal MCV but elevated RDW 1, 4
• Don't rely solely on RDW: Lacks specificity for particular conditions 1
• Don't overlook mixed deficiencies: Concurrent B12/folate and iron deficiency can result in normocytic indices despite significant abnormalities 1, 2
• Don't forget CKD evaluation: Anemia of CKD is typically normocytic/normochromic and becomes more prevalent as GFR declines 3, 1
• In men and post-menopausal women with iron deficiency: Always investigate for gastrointestinal malignancy with upper endoscopy and colonoscopy 3, 2