Inflammatory Bowel Disease with Iron Deficiency and Anemia Clinical Pathway — All Settings

Iron Therapy

Decision to Treat with Oral versus Intravenous Iron is based on:

  • Severity of anemia
  • Disease activity
  • Tolerance to oral iron formulation

IV Iron Therapy

Recommended in the following scenarios:

  • Patients with active IBD
    Rationale: Decreased intestinal iron absorption secondary to mucosal inflammation and increased hepcidin levels. Potential exacerbation of bowel inflammation and increased intolerance with oral iron.
  • Moderate to severe anemia
  • History of previous intolerance to oral iron

Preferred formulation - Ferric Carboxymaltose (FCM)

  • Can be administered at higher doses, up to 15mg/kg/dose, shortening treatment duration
  • Provides a more rapid response compared to iron sucrose
  • Currently, only available at CHOP in the outpatient setting for children ≥ nine months old

Oral Iron Therapy

Considered in the following scenarios:

  • Patients with inactive/quiescent IBD
  • Iron deficiency with or without mild anemia
  • No history of previous intolerance to oral iron

Special Situation-Functional Iron Deficiency

The evidence for iron supplementation in cases of functional ID (as defined by a ferritin ≥ 100 ug/L and TSAT < 20% in state of active disease) in IBD is less robust and mostly comes from chronic kidney disease evidence. Expectant management (e.g. awaiting spontaneous hematological recovery) may be considered in cases of patients with asymptomatic mild to moderate anemia for whom rapid induction of remission is expected.

Iron Therapy Guidance

Oral Iron

Dosing and Duration Tips and Recommendations
  • Dose: 3 - 6 mg/kg/d elemental Fe
  • MAX 100 mg/d
  • Duration: 4 - 6 months
  • Re-evaluate according to therapeutic goals
  • Available formulations:
    • Immediate-release (e.g. ferrous sulfate)
      • May have higher absorption
      • May be associated with more GI adverse effects (e.g. constipation)
  • Slow-release or enteric coated products (e.g. polysaccharide iron complex)
    • May have lower absorption
    • May be better tolerated (less GI adverse effects)
    • Once daily dosing
  • To optimize absorption of oral iron: take in the morning and consider vitamin C supplementation (25 mg once a day)
  • Concomitant fibers, calcium intake may decrease absorption.
  • If concern for constipation, consider use of a laxative:
    • PEG 3350
      • Children < 20 kg: 8.5 g (1/2 capful) of powder in 4 oz of liquid
      • Children ≥ 20 kg and Adults: 17 g (1 capful) of powder in 8 oz of liquid
    • Docusate 20 mg daily (< 6 years) or
    • Docusate 100 mg daily(≥ 6 years)

Intravenous Iron

Dosing and Duration Tips and Recommendations
  • Ferric Carboxymaltose (FCM)
    • Dose: 15 mg/kg/dose
    • MAX dose 750 mg/d
  • Total replacement dose:
    • Non-anemic iron deficiency: 1 dose is usually sufficient
  • Iron deficiency anemia: 2 doses, ≥ 7 days apart, is usually sufficient.
  • Alternatively the Ganzoni formula may be used:
    (BW (kg) x [target UNL for Hb-actual Hb (g/dL)] x 0.24 + 500)
  • FCM is currently only available in the outpatient setting at CHOP.
  • Iron Sucrose
    • 5 - 7 mg/kg/dose
    • MAX dose 300 mg/d
  • Give doses every 3 - 7 days until the total replacement dose is administered
  • Total replacement dose calculation:
      Ganzoni formula
      (BW (kg) x [target UNL for Hb-actual Hb (g/dL)] x 0.24 + 500)

Benefits and Limitations of Oral Versus Intravenous Iron

  Benefits Limitations
Oral Iron
  • Ease of use
  • Low intestinal absorption of iron (~20%)
    • → Slow and limited efficacy
    • → Requires longer treatment course
  • Ineffective in state of active disease
  • May aggravate intestinal inflammation
  • Requires intake daily or multiple times per day
  • GI intolerance common
  • Low adherence to treatment
IV Iron
  • Increased iron bioavailability compared to oral iron
  • Effective in the presence of inflammation
  • No GI side effects
  • IV administration ensures treatment adherence
  • Requires medical expertise for administration and facilities
  • Rare hypersensitivity reaction may occur
  • More expensive than oral iron