II. Causes

  1. Iron Deficiency Anemia (most common)
    1. Decreased Serum Iron level
    2. Increased Total Iron Binding Capacity
    3. Decreased Transferrin Saturation
  2. Thalassemia
    1. Normal iron studies
    2. Differentiated with Hemoglobin electrophoresis
  3. Anemia of Chronic Disease
    1. Decreased Serum Iron, TIBC and Transferrin Saturation
  4. Sideroblastic Anemia
    1. Similar workup as with Thalassemia
  5. Lead Poisoning
  6. Copper Deficiency
  7. Zinc Toxicity
  8. Hemoglobinopathy

III. Labs

  1. Complete Blood Count
    1. See Hemoglobin Cutoffs for Anemia
    2. See Hematocrit Cutoffs for Anemia
    3. Mean Corpuscular Volume (MCV) <80
      1. See MCV Cutoffs for Microcytic Anemia
      2. MCV cutoff varies by age and per reference
  2. Serum Iron
    1. Decreased in Iron Deficiency Anemia and Anemia of Chronic Disease
  3. Total Iron Binding Capacity (TIBC)
    1. Increased in Iron Deficiency Anemia
    2. Decreased in Anemia of Chronic Disease
  4. Transferrin Saturation
    1. Near complete saturation in Sideroblastic Anemia
    2. Less than 5% saturated in Iron Deficiency Anemia
  5. Ferritin Level
    1. Ferritin <15 ng/ml suggests Iron Deficiency Anemia
    2. Ferritin is acute phase reactant and also elevated in chronic inflammation
      1. Use cutoff of <50 ng/ml to diagnose Iron Deficiency Anemia when comorbid inflammatory condition present
  6. Reticulocyte Index <1% (Reticulocytopenia)
    1. See Anemia for causes of Reticulocytosis
  7. Mean Corpuscular Volume to Red Blood Cell Count ratio
    1. See Mentzer Index
    2. Ratio <13: Thalassemia
    3. Ratio >13: Iron Deficiency Anemia, Hemoglobinopathy

IV. Labs: Hemoglobin Electrophoresis

  1. Indications
    1. Suspected Hemoglobinopathy (e.g. Thalassemia)
    2. Normal Serum Iron, Transferrin Saturation, and TIBC (esp. in young patients)
  2. Interpretation
    1. Increased Hemoglobin A2 Level
      1. Beta Thalassemia
    2. Normal Hemoglobin A2 Level
      1. Sideroblastic Anemia
      2. Alpha-Thalassemia trait

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Related Studies

Ontology: Microcytic hypochromic anemia (disorder) (C0271901)

Definition (CSP) anemia featuring pale erythrocytes smaller than 6 microns in diameter; typically due to iron deficiency or abnormalities in hememetabolism.
Concepts Disease or Syndrome (T047)
MSH C536357
SnomedCT 191126000, 191130002, 44666001
Dutch hypochrome microcytaire anemie, hypochrome microcytische anemie, anemie hyperchroom macrocytair beeld, hypochrome microcytische beeldanemie, anemie; hypochroom, microcytair, anemie; microcytair, hypochroom
French Anémie microcytaire hypochrome, Anémie - Tableau microcytaire hypochrome
German hypochrom-mikrozytaere Anaemie, Anaemie-hypochrom-mikrozytaeres Bild
Italian Anemia microcitica ipocromica, Anemia, quadro ipocromico microcitico
Portuguese Anemia microcítica hipocrómica, Anemia hipocrómica com quadro microcítico
Spanish Anemia. Imagen microcítica hipocrómica, Anemia hipocrómica microcítica, anemia hipocrómica microcítica [dup], anemia hipocrómica microcítica [dup] (trastorno), anemia hipocrómica microcítica, anemia microcítica hipocrómica (trastorno), anemia microcítica hipocrómica
Japanese 貧血・低色素性小球像, 低色素性小球性貧血, ヒンケツテイシキソセイショウキュウゾウ, テイシキソセイショウキュウセイヒンケツ
English Hypochromic, microcytic anemia, hypochromic microcytic anemia (diagnosis), hypochromic microcytic anemia, hypochromic / microcytic anemia, Anaemia- Hypochromic microcytic picture, Anemia- Hypochromic microcytic picture, Microcytic, hypochromic anemia, Microcytic hypochromic anemia (disorder), Anemia, hypochromic microcytic, anemia microcytic hypochromic, anemias hypochromic microcytic, hypochromic microcytic anaemia, microcytic hypochromic anemia, microcytic hypochromic anaemia, microcytic/hypochromic anemia, Anemia, microcytic hypochromic, Microcytic - hypochromic anemia, Microcytic - hypochromic anaemia, Hypochromic - microcytic anaemia, Hypochromic - microcytic anemia, Hypochromic microcytic anemia, Microcytic hypochromic anemia, Hypochromic microcytic anaemia, Microcytic hypochromic anaemia, anemia; hypochromic, microcytic, anemia; microcytic, hypochromic, Microcytic hypochromic anemia [dup] (disorder)
Czech Hypochromní mikrocytová anémie, Anémie hypochromní mikrocytová
Hungarian hypochrom microcytaer anaemia, Hypochrom microcytás anaemia, Hypochrom microcytaer anaemia, hypochrom microcytás anaemia