[Hemonc] when are you going to stop iron supplement?

[Category] Topic; 1. Workup; 2. Management; 3. Tip and Teaching point; 4. References;

Treatment 

Oral regimen: Ferrous sulfate 325mg(element iron 65mg) every other day or M/W/F. For 2 months of normalization in Hgb and 6 more months for storage. If pt. couldn't tolerate it, then switch to Ferrous fumarate or gluconate (with less element iron; 36, 33 mg respectively) 

IV regimen: 

 1) calculate dose by the website link

 2) Iron dextran; single dose like 1000mg for an hour infusion(preferred choice)

 3) Venofor, Ferrlecit, Feraheme, or Injectafer: multiple doses. 

Adverse event of IV iron(including anaphylaxis) 

 1) Do not inject during infection

 2) Anaphylaxis = Methylprednisolone + Diphenhydramine + 1:1000 EPI(0.1mg shot) 

     but minor reaction = Slow down infusion without antihistamien(which can make it worse) 

     but if it's not improving, then consider methylprednisolone. 

 3) monitor as below.

Monitoring and hemoglobin/iron targets — Monitoring of patients receiving iron replacement depends on the severity of anemia.

Oral iron: recheck in two weeks with hemoglobin(2g per 3 weeks) and reticulocyte count(1 week), and review tolerability of medication. 

IV iron: recheck 4-8 weeks. Do not repeat iron parameters(for four weeks) 

cf. Patients with ongoing blood loss may require earlier visits to establish an effective iron dose and teach the patient how to monitor ongoing blood loss.

Goal: until levels of ferritin and transferrin saturation normalize(oral for 8 months vs iv for 2months?). When ferritin and transferrin saturation are discordant, we place greater emphasis on the transferrin saturation (TSAT). 

cf. Ferritin is an acute phase reactant of inflammation. 

Lack of response:  1) non-compliance 2) decreased absorption(screen celiac disease, autoimmune gastritis, H.pylori infection, Vit B12 deficiency)  3) bleeding 4) inflammation prevent intestinal iron regulation.

Other ddx. nutrient deficiencies (vitamin B12, folate), bone marrow abnormalities (myelodysplastic syndrome), inherited anemias (thalassemia; check RBC count vs hemoglobin level + peripheral smear., enzyme defects), hypothyroidism, other genetic conditions that affect iron balance such as iron-resistant iron deficiency anemia (IRIDA), and disorders associated with chronic inflammation. 

[REF: Uptodate] 

Suggested note for IDA

# Anemia:  

likely 2/2 GI bleeding related IDA

less likely anemia of chronic disease, chronic inflammation(ESR, CRP?) 

less likely 2/2 thalassemia, Vit B 12 deficiency, folate defieicny(more likely macrocytic but can be combinated) nor BM disease

-Iron labs: serum iron, ferritin, transferrin, transferrin saturation(TIBC)

-Vitamin B12, folate level

-peripheral smear

=>

ferritin <20 in men, <10 in women = regardless other possibility, pt. has IDA(can be combinated with other disease though)

-start ferrous sulfate 325mg every other day for 8 months, f/u in 2 weeks

-or iv iron dextran 1000mg once,f/u in 2 months