What is the appropriate management and treatment plan for a patient with microcytic hypochromic anemia and iron deficiency?

Interpretation and Management of Iron Deficiency Anemia

Laboratory Interpretation

Your labs demonstrate classic iron deficiency anemia: microcytic hypochromic anemia (Hb 9.7, MCV 73, MCH 21.0, MCHC 28.5) with severely depleted iron stores (ferritin 32, iron saturation 7%, TIBC 445). 1

The key diagnostic findings are:

• Microcytic anemia (MCV 73, normal >80) with hypochromia (MCHC 28.5, normal >32) indicating iron-deficient red cell production 1
• Severe iron depletion with iron saturation of only 7% (normal >20%) and elevated TIBC of 445 (normal 250-370), reflecting the body's attempt to capture any available iron 1
• Low serum ferritin at 32 ng/mL, which is the most powerful test for confirming iron deficiency 1
• Elevated RDW at 18.3 indicating significant variation in red cell size, typical of iron deficiency 1

Immediate Management Plan

Start oral iron supplementation with ferrous sulfate 200 mg three times daily immediately to correct anemia and replenish iron stores. 1, 2, 3

Iron Supplementation Protocol

• First-line therapy: Ferrous sulfate 200 mg orally three times daily 1, 2
• Alternative oral preparations if ferrous sulfate is not tolerated: ferrous gluconate or ferrous fumarate are equally effective 1
• Take with meals if gastrointestinal discomfort (nausea) occurs, though this may slightly reduce absorption 3
• Add ascorbic acid (vitamin C) if response is poor, as it enhances iron absorption 1
• Continue for 3 months after anemia correction to fully replenish body iron stores 1, 2

Expected Response and Monitoring

• Hemoglobin should rise by 2 g/dL after 3-4 weeks of treatment 1, 2
• If this response does not occur, consider: poor compliance, continued blood loss, malabsorption, or misdiagnosis 1, 2
• Monitor hemoglobin and MCV every 3 months for the first year, then annually 1, 2

Mandatory Investigation for Underlying Cause

All patients with confirmed iron deficiency anemia require investigation to identify the source of blood loss, regardless of age or gender. 1

Required Workup

• Upper and lower GI investigations (esophagogastroduodenoscopy and colonoscopy) should be performed unless there is documented significant non-GI blood loss 1
• Screen for celiac disease in all patients, as malabsorption is an important treatable cause 1, 2
• Colonoscopy is preferred over CT colonography for lower GI investigation, though either is acceptable 1
• Only advanced gastric cancer or confirmed celiac disease on upper endoscopy should deter lower GI investigation 1

Do NOT Order

• Fecal occult blood testing has no benefit in iron deficiency anemia workup—it is insensitive and non-specific 1, 2

When to Consider Parenteral Iron

Switch to intravenous iron only if oral iron is not tolerated after trying at least two different oral preparations, or if there is documented malabsorption. 1, 2

Parenteral iron indications:

• Intolerance to at least two oral iron preparations 1
• Malabsorption disorders preventing oral iron absorption 4
• Ongoing blood loss exceeding intestinal iron absorption capacity 5

Note: IV iron is more expensive, carries risk of anaphylactic reactions, and provides no faster hemoglobin rise than oral preparations 1

Common Pitfalls to Avoid

• Do not assume any single cause without thorough investigation—multiple etiologies often coexist 6
• Do not stop investigating if initial workup is negative and hemoglobin cannot be maintained with iron therapy 1, 2
• Do not use blood transfusions unless hemoglobin is <7-8 g/dL or there are severe symptoms with cardiovascular instability 1
• Do not forget to continue iron for 3 months after correction—stopping too early will not replenish stores and anemia will recur 1, 2
• Failure to respond to oral iron after 3-4 weeks usually indicates poor compliance, continued bleeding, or malabsorption—not inadequate dosing 1, 2