What are the symptoms and treatment of low ferritin levels?

Symptoms and Treatment of Low Ferritin

Low ferritin levels can cause a range of symptoms including fatigue, exercise intolerance, difficulty concentrating, irritability, depression, restless legs syndrome, pica, hair loss, and worsening of chronic conditions, even before anemia develops. 1, 2

Symptoms of Low Ferritin

Common Symptoms

• Fatigue and weakness - often the earliest and most common symptom
• Exercise intolerance - reduced physical performance and endurance
• Cognitive symptoms - difficulty concentrating, irritability, depression
• Restless legs syndrome - affects 32-40% of iron-deficient individuals 2
• Pica (craving non-food items) - affects 40-50% of iron-deficient individuals 2
• Hair loss - diffuse telogen effluvium may occur with ferritin below 30-40 μg/L 3, 4

Advanced or Severe Symptoms (with anemia)

• Dyspnea and lightheadedness
• Headache and dizziness
• Pale skin and mucous membranes
• Tachycardia
• Worsening of heart failure symptoms in patients with cardiac conditions 2

Special Populations

• Children: developmental delays, decreased motor activity, reduced social interaction, diminished attention to tasks, behavioral disturbances 1
• Pregnant women: increased risk for preterm delivery and low-birthweight babies 1, 2
• Patients with chronic conditions: exacerbation of symptoms in inflammatory bowel disease, chronic kidney disease, heart failure, and cancer 1, 2

Diagnosis of Low Ferritin

Diagnostic Criteria

• Non-inflammatory conditions: serum ferritin <30 μg/L indicates absolute iron deficiency 1
• Inflammatory conditions or chronic disease: serum ferritin <100 μg/L may indicate iron deficiency 5, 1
• Transferrin saturation <16-20%: indicates iron deficiency even with normal ferritin 1

Laboratory Assessment

• Complete blood count with red cell indices
• Serum ferritin
• Transferrin saturation (iron/total iron binding capacity × 100)
• Red Cell Distribution Width (RDW) >14% suggests iron deficiency 1
• Mean Cell Hemoglobin (MCH) - more reliable than MCV for detecting iron deficiency 1

Treatment of Low Ferritin

Oral Iron Supplementation

• First-line therapy for most patients with iron deficiency 2
• Dosage: Ferrous sulfate 325 mg (containing 65 mg elemental iron) daily or on alternate days 6, 2
• Duration: Continue treatment for at least 3 months after normalization of hemoglobin to replenish iron stores 1
• Monitoring: Recheck hemoglobin after 4 weeks of treatment to confirm response 1

Intravenous Iron

Indicated for patients with:

• Oral iron intolerance
• Poor absorption (celiac disease, post-bariatric surgery)
• Chronic inflammatory conditions (CKD, heart failure, IBD, cancer)
• Ongoing blood loss
• Second and third trimesters of pregnancy 2

Dietary Recommendations

• Increase consumption of iron-rich foods:
  • Heme iron sources: red meat, seafood
  • Non-heme iron sources: leafy greens, beans, iron-fortified cereals
• Include vitamin C-rich foods with meals to enhance non-heme iron absorption
• Avoid iron absorption inhibitors with meals (tea, coffee, calcium-rich foods, whole grain cereals) 1

Monitoring and Follow-up

• Measure hemoglobin after 4 weeks of treatment to confirm response 1
• Monitor ferritin levels monthly during initial treatment phase 1
• Continue monitoring every 6 months during maintenance phase 1
• Target ferritin levels:
  • General population: 50-100 μg/L 5, 1, 7
  • Women: >40 μg/L (especially for those with hair loss) 4

Common Pitfalls and Caveats

1. Underdiagnosis in women: Standard laboratory reference ranges often underdiagnose iron deficiency in women, as 30-50% of healthy women may have no marrow iron stores 7

2. Misinterpretation with inflammation: Ferritin is an acute phase reactant and may be falsely elevated in inflammatory conditions, masking iron deficiency 5, 1

3. Excessive phlebotomy: Avoid excessive phlebotomy in patients with hemochromatosis, as this can lead to symptomatic iron deficiency 5

4. Iron overload risk: Long-term iron supplementation can lead to iron overload in susceptible individuals; monitor ferritin levels regularly 5

5. Incomplete evaluation: Failure to identify and address the underlying cause of iron deficiency (bleeding, malabsorption, dietary insufficiency) 2

By addressing both the symptoms and underlying causes of low ferritin, patients can experience significant improvement in their quality of life and prevention of complications related to iron deficiency.