Iron deficiency anemia

Iron deficiency anemia - Chronic
Rahul Soman, M. Pharm

 

Definition  

A reduction in serum RBC concentration due to inadequate iron stores in the body which results in formation of hypochromic, microcytic erythrocytes

 

Medical History  

* Gastrointestinal hemorrhage, chronic

* Menorrhagia

* Pregnancy

* Malabsorption syndrome

* Iron deficiency anemia secondary to inadequate dietary iron intake

 

Findings  

* Dyspnea - Chronic

* Sinus tachycardia

* Angular cheilitis

* Atrophic condition of skin

* Fatigue

* Headache

* Koilonychia

* Pallor

* Pica

* Telangiectasia

* Splenomegaly

 

Tests  

 

Suspected iron deficiency anemia  

* Complete blood count with white cell differential, manual

 

Screening for iron deficiency anemia  

* Measurement of total hemoglobin concentration: Two Hgb values below the accepted threshold are presumptive for iron-deficiency anemia. The diagnosis can be confirmed if hgb values rise to 1 g/dL or greater after 4 weeks of iron supplementation therapy .

 

Suspected anemia  

* Hematocrit determination: Very mild anemias are associated with few or no clinical signs or symptoms; therefore, a mild anemia usually is first detected from a screening measurement of Hgb or HCT.

 

Anemia  

* Peripheral blood smear examination, light microscopy: Blood smear examination is indicated in the initial evaluation of suspected or unexplained anemia .

 

Suspected or known anemia  

* Reticulocyte count: The reticulocyte count is essential for differentiating between anemias arising from nonfunctional versus functional bone marrow .

 

Suspected iron deficiency anemia  

* Erythrocyte mean corpuscular volume determination: A low mean corpuscular volume (< 80 fL), together with a low RBC count and high red cell distribution width, favors the diagnosis of iron deficiency .

 

Suspected iron deficiency to evaluate presence of hypochromic anemia  

* Mean corpuscular hemoglobin concentration determination

 

Suspected iron deficiency anemia  

* Red cell distribution width determination: An increased red cell distribution width (RDW) is an early hematologic manifestation of iron deficiency anemia .

 

Suspected iron deficiency  

* Serum iron measurement: Low serum iron in the presence of elevated total iron-binding capacity and low serum ferritin is considered diagnostic for iron deficiency .

 

Suspected iron-deficiency anemia  

* Total iron binding capacity measurement: Total iron binding capacity is a useful test in evaluating iron-deficiency anemia, but only in conjunction with other iron studies .

 

Suspected iron deficiency anemia  

* Serum ferritin measurement: A ferritin level of 15 mcg/L or less is a marker of depleted or absent iron stores, and confirms iron deficiency anemia in the presence of low Hgb or HCT .

Suspected or known iron deficiency  

* Transferrin saturation index: An iron saturation of less than 16% in the presence of an increased transferrin concentration differentiates iron deficiency from inflammation .

 

Suspected gastrointestinal bleeding  

* Screening for occult blood in feces: A positive fecal occult blood test may reflect gastrointestinal bleeding and colonoscopy or upper endoscopy may be indicated .

 

Suspected gastrointestinal bleeding in Henoch-Schönlein purpura  

* Screening for occult blood in feces

 

Unexplained iron deficiency anemia to determine potential locations of blood loss  

* Esophagogastroduodenoscopy

* Colonoscopy

 

Differential Diagnosis  

* Hemorrhage

* Anemia of chronic disease - Chronic

* Anemia of pregnancy

* Thalassemia - Chronic

* Sideroblastic anemia

* Hemolytic anemia

* Aplastic anemia - Acute

* Leukemia

* Megaloblastic anemia

* Myelodysplastic syndrome - Chronic

 

Treatment  

 

Drug Therapy  

 

Anemia of pregnancy  

 

FOLIC ACID  

Adults: 400 mcg orally once daily

 

Iron deficiency anemia  

 

FERROUS SULFATE  

Adults: 300 to 325 mg orally 3 times daily between meals until ferritin and Hgb are normal

 

FERROUS GLUCONATE  

Adults: 300 to 325 mg orally 3 times daily between meals until ferritin and Hgb are normal

 

FERROUS FUMARATE  

Adults: 300 to 325 mg orally 3 times daily between meals until ferritin and Hgb are normal