Hematology Oncology · Year 2 · from Hematology Oncology
Case 1: Iron Deficiency Anemia in a Young Woman
Patient Presentation
Demographics: 28-year-old female
Chief Complaint: Progressive fatigue and shortness of breath over 4 months
History of Present Illness: The patient reports gradually worsening fatigue that has begun to affect her work performance. She notes dyspnea on exertion when climbing stairs, which was not present previously. She also reports occasional pica, specifically craving ice (pagophagia). She has heavy menstrual periods lasting 7-8 days with frequent pad changes. She denies any melena, hematochezia, or hematemesis. Her diet consists mostly of vegetables with limited red meat intake.
Physical Examination:
- Vital signs: BP 108/68, HR 98, RR 18, Temp 36.8C
- General: Pale-appearing young woman, appears fatigued
- HEENT: Conjunctival pallor, glossitis with smooth tongue, angular cheilitis
- Cardiac: Tachycardic, II/VI systolic flow murmur at left sternal border
- Abdomen: Soft, non-tender, no hepatosplenomegaly
- Extremities: Koilonychia (spoon-shaped nails) noted bilaterally
- Neurologic: Normal
Workup and Results
Complete Blood Count:
- WBC: 6,800/uL (normal)
- Hemoglobin: 8.2 g/dL (low, normal 12-16)
- Hematocrit: 25%
- MCV: 68 fL (low, normal 80-100)
- MCH: 24 pg (low)
- MCHC: 30 g/dL (low)
- RDW: 18% (elevated)
- Platelets: 420,000/uL (mildly elevated)
- Reticulocyte count: 0.8% (inappropriately low)
Iron Studies:
- Serum iron: 25 mcg/dL (low, normal 60-170)
- Total iron-binding capacity (TIBC): 480 mcg/dL (elevated, normal 250-370)
- Transferrin saturation: 5% (low, normal 20-50%)
- Ferritin: 8 ng/mL (low, normal 12-150)
Peripheral Blood Smear:
- Hypochromic, microcytic red blood cells
- Increased central pallor
- Anisocytosis and poikilocytosis
- Pencil cells present
- No target cells or basophilic stippling
Clinical Image
Peripheral blood smear showing hypochromic, microcytic red blood cells with increased central pallor characteristic of iron deficiency anemia. Image source: Wikimedia Commons, Dr Graham Beards. License: CC BY-SA 3.0
Diagnosis
Iron Deficiency Anemia secondary to Menorrhagia
Diagnostic criteria met:
- Microcytic anemia (MCV < 80 fL)
- Low ferritin (< 30 ng/mL) - most sensitive single test
- Low serum iron with elevated TIBC
- Transferrin saturation < 20%
- Elevated RDW reflecting anisocytosis
- Clinical features: pagophagia, koilonychia, glossitis
Treatment Plan
- Identify and address underlying cause:
- Gynecology referral for evaluation of menorrhagia
- Consider hormonal management to reduce menstrual blood loss
- Oral iron replacement:
- Ferrous sulfate 325 mg (65 mg elemental iron) three times daily
- Take on empty stomach if tolerated; with food if GI side effects occur
- Take with vitamin C to enhance absorption
- Avoid concurrent intake of calcium, tea, or coffee
- Monitoring:
- Reticulocyte count in 5-7 days (should increase)
- CBC every 4 weeks until hemoglobin normalizes
- Continue iron for 3-6 months after hemoglobin normalizes to replenish stores
- Check ferritin to confirm store repletion (goal > 50 ng/mL)
Teaching Points
- Iron deficiency anemia is the most common cause of anemia worldwide
- Ferritin is the most sensitive single test for iron deficiency; values < 30 ng/mL are diagnostic
- Low serum iron with elevated TIBC produces a low transferrin saturation (< 20%)
- Clinical features include pagophagia (ice craving), koilonychia (spoon nails), glossitis, and angular cheilitis
- Always identify the source of iron loss - in premenopausal women, menorrhagia is most common; in postmenopausal women and men, GI bleeding must be excluded
- The reticulocyte count is inappropriately low, indicating a production problem rather than hemolysis