Description

This patient presented with normal WBC, platelet and RBC counts; however, hemoglobin, hematocrit and MCV were below the reference range. MCH and MCHC were low and the RDW was normal.

Peripheral smear examination revealed uniformly small RBC with increased central pallor, moderate number of target cells and few ovalocytes. There was no evidence of an increase in polychromasia, which correlates with the reticulocyte count of 1.98 %.

These findings are consistent with a diagnosis of microcytic hypochromic anemia.

The microcytic anemias are a group of anemias with different etiologies. However, all are characterized by the presence of smaller sized red blood cells (microcytes). The normal MCV is 80-100 fL. RBC smaller than 80 fL are described as microcytic while larger cells (>100 fL) are called macrocytic.

In microcytic anemia, the red blood cells are most often also hypochromic. These cells appear paler than usual because of decreased intracellular hemoglobin. This is usually reflected by a lower than normal MCHC (normal range: 320-360 g/L or 32-36 g/dL). Thus, this type of anemia is described as “microcytic, hypochromic anemia.”

The most common cause of microcytic hypochromic anemia is iron deficiency, but in this case the presence of a moderate number of target cells makes beta thalassemia a possible differential diagnosis. Anemia of chronic disease/inflammation (ACD) should also be considered, although ACD is usually normocytic to mildly microcytic (MCV: 75-85 fL). Patients with iron deficiency anemia most often present with low RBC count; however, not in this case.