Diagnosis and Treatment of Microcytic Anemia with Multiple Metabolic Abnormalities

Primary Diagnosis

This patient has severe iron deficiency anemia (IDA) requiring immediate oral iron supplementation and urgent investigation for gastrointestinal blood loss. 1, 2

The laboratory findings confirm microcytic, hypochromic anemia with hemoglobin 8.4 g/dL (normal >12 g/dL in women), MCV 74 fL (normal 80-100 fL), MCH 21.9 pg (low), and MCHC 29.7 g/dL (low). 2 The elevated RDW of 16.5% combined with low MCV strongly indicates iron deficiency rather than thalassemia trait. 2, 3

Immediate Management Algorithm

Step 1: Confirm Iron Deficiency and Initiate Treatment

Order serum ferritin immediately as the single most powerful diagnostic test for iron deficiency. 1, 2
- Ferritin <30 μg/L confirms iron deficiency 2
- Ferritin <45 μg/L provides optimal sensitivity and specificity in practice 2
- If ferritin is 30-100 μg/L, add transferrin saturation (TSAT <16-20% confirms iron deficiency) 2, 3
Start oral ferrous sulfate 200 mg three times daily immediately while awaiting iron studies. 2
- Continue for at least 3 months after hemoglobin normalizes to replete iron stores 2
- Add ascorbic acid (vitamin C) to enhance absorption 2
- Alternative formulations (ferrous gluconate or ferrous fumarate) if not tolerated 2
Expect hemoglobin rise ≥10 g/L (≥1 g/dL) within 2 weeks if iron deficiency is the cause. 2

Step 2: Investigate the Source of Iron Loss

In a 43-year-old woman, the two most common sources are menstrual blood loss and gastrointestinal bleeding. 1, 4

Menstrual History Assessment

Obtain detailed menstrual history focusing on:
- Duration of menses (>7 days suggests menometrorrhagia) 4
- Frequency of pad/tampon changes (>1 per hour suggests heavy bleeding) 4
- Passage of clots 4
- Years of heavy bleeding (chronic menometrorrhagia can cause profound anemia) 4

Gastrointestinal Evaluation

All adult women with confirmed IDA require GI investigation unless menorrhagia clearly explains the entire picture. 1
Upper endoscopy with small bowel biopsies to exclude:
- Celiac disease (present in 2-3% of IDA patients) 1, 2
- Gastric cancer 1
- NSAID-induced gastropathy 1
- Peptic ulcer disease 1
Colonoscopy or barium enema to exclude:
- Colonic cancer/polyps 1
- Angiodysplasia 1
- Inflammatory bowel disease 1
Stool guaiac testing for occult blood 5

Step 3: Monitor Response and Adjust Treatment

Recheck complete blood count in 2-4 weeks. 2
- If hemoglobin rises ≥1 g/dL, continue oral iron 2
- If no response, consider:
  - Non-compliance 2
  - Ongoing blood loss 2
  - Malabsorption (celiac disease, H. pylori, atrophic gastritis) 2
  - True intolerance to oral iron 2
Switch to intravenous iron (iron sucrose or iron gluconate) if malabsorption confirmed or oral iron fails. 2
- Expect hemoglobin increase ≥2 g/dL within 4 weeks 2
Monitor hemoglobin and MCV every 3 months for 1 year, then annually. 2

Secondary Diagnoses and Management

Pre-Diabetes (A1c 6.1%)

This patient has pre-diabetes requiring lifestyle modification. 5

Initiate intensive lifestyle intervention:
- Weight loss of 7% body weight if overweight 5
- 150 minutes/week moderate-intensity physical activity 5
- Dietary counseling focusing on reduced refined carbohydrates 5
Recheck A1c in 3-6 months. 5
Metformin may be considered if lifestyle modification fails and patient has additional risk factors (BMI >35, age <60, history of gestational diabetes). 5

Severe Hypertriglyceridemia (Triglycerides 407 mg/dL)

This patient has severe hypertriglyceridemia requiring immediate treatment to prevent pancreatitis. 5

Triglycerides >400 mg/dL carry significant pancreatitis risk and require pharmacotherapy. 5
Start high-intensity statin therapy (atorvastatin 40-80 mg or rosuvastatin 20-40 mg daily) for cardiovascular risk reduction. 5
- LDL 116 mg/dL is above optimal (<100 mg/dL) 5
- Total cholesterol 238 mg/dL is elevated 5
Add fenofibrate 145 mg daily or omega-3 fatty acids (icosapent ethyl 2-4 g daily) specifically for triglyceride reduction. 5
Strict dietary modification:
- Eliminate alcohol completely 5
- Restrict simple carbohydrates and sugars 5
- Limit total fat intake to <30% of calories 5
Recheck lipid panel in 6-8 weeks after initiating therapy. 5

Leukocytosis (WBC 13.5, Neutrophils 8.5)

The mild leukocytosis with neutrophilia is likely reactive and secondary to chronic anemia stress, but requires follow-up. 5

Recheck CBC after iron repletion to ensure leukocytosis resolves. 5
If persistent after anemia correction, consider:
- Occult infection 5
- Inflammatory process 5
- Smoking history 5
- Medications causing leukocytosis 5

Critical Pitfalls to Avoid

Do not assume all microcytic anemia is iron deficiency. Anemia of chronic disease, thalassemia, and sideroblastic anemia require different management. 2, 3
Do not attribute IDA in adults to dietary insufficiency alone. Blood loss must be excluded, particularly GI malignancy. 1, 2
Do not use ferritin alone in the presence of inflammation. Add transferrin saturation, as ferritin can be falsely elevated by inflammation. 2, 3
Do not overlook combined deficiencies. Iron deficiency can coexist with B12 or folate deficiency, recognizable by elevated RDW. 1, 5
Do not delay GI investigation in adults with confirmed IDA. Even if menorrhagia seems explanatory, occult GI pathology must be excluded. 1
Do not stop iron supplementation when hemoglobin normalizes. Continue for 3 months after correction to replete iron stores. 2
Do not ignore triglycerides >400 mg/dL. This level requires immediate pharmacotherapy to prevent acute pancreatitis. 5

Follow-Up Schedule

Week 2-4: Recheck CBC to confirm hemoglobin response to iron 2
Week 6-8: Recheck lipid panel after statin/fibrate initiation 5
Month 3: Recheck A1c to assess pre-diabetes response 5
Month 3,6,9,12: Monitor CBC and iron studies 2
Year 1: Annual CBC, lipid panel, A1c 5, 2

Help us tailor your experience