A useful review of microcytic anemia (NEJM 2014; 371: 1324-31) discusses the most common causes, mechanisms and treatment of microcytic anemia.

Common causes discussed include thalassemia, iron deficiency anemia, and anemia of inflammation.  With the latter, the authors review the pathophysiology: “the cause of this anemia is twofold. First, renal production of erythropoietin is suppressed by inflammatory cytokines, resulting in decreased red-cell production. Second, lack of iron availability for developing red cells can lead to microcytosis.  The lack of iron is largely due to the protein hepcidin, an acute-phase reactant that leads to both reduced iron absorption and reduced release of iron from body stores.”

Treatment of iron deficiency anemia –pointers:

• Ferrous sulfate (325 mg [65 mg of elemental iron] orally three times a day -considered first line for adults.  Ferrous gluconate at a daily dose of 325 mg [35 mg elemental] is an alternative.
• “Several trials suggest that lower doses of iron, such as 15 to 20 mg of elemental iron daily can be as effective as higher doses and have fewer side effects.”
• “There are many oral iron preparations, but no one compound appears to be superior to another.”
• In those with an inadequate response to oral iron therapy, parenteral iron can be helpful.  The authors note that low-molecular-weight iron dextran (INFeD) is “associated with an incidence of reactions that is similar to that with the newer products but allows for higher doses of iron replacement.”  Typical dosing for adults: 25 mg test dose, and if tolerated for 1 hr, can give 975 mg (1000 mg total) over 4-6 hours.  The low-molecular-weight iron dextran should not be used in patients with previous iron dextran hypersensitivity reactions.
• Alternative IV iron products: Ferric gluconate [Ferrlecit] 125 mg adult dose over 1 hour -given weekly (8 doses = 1000 mg) or Iron Sucrose [Venofer] 200 mg adult dose over 15-60 min, 300 mg over 1.5 hr, or 500 mg over 4 hr; can repeat in subsequent sessions until total dose of 1000 mg.

Related blog posts:

• Less Red Meat, More Anemia | gutsandgrowth
• Inadequate treatment of anemia in IBD | gutsandgrowth
• Help with hepcidin | gutsandgrowth

Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) should be confirmed by prescribing physician.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.