Reticulocyte Count

This test measures the amount of reticulocytes in blood. Reticulocytes are new red blood cells. This test is used to help evaluate the bone marrow's ability to produce red blood cells (RBC's) and to help manage anemia. It is usually done if you have a decreased (or increased) RBC count, hemoglobin, and hematocrit and your caregiver wants to evaluate bone marrow function.

Occasionally, both the reticulocyte count and the RBC count will be increased because of excess RBC production. This may be due to a variety of causes including inappropriately increased production of erythropoietin, disorders that chronically produce increased numbers of RBC's (polycythemia vera), and even smoking.

SAMPLE COLLECTION

A blood sample is obtained by inserting a needle into a vein in the arm or sometimes from pricking a finger or the heel of an infant.

NORMAL FINDINGS

  • Adults: 0.5%-2.5% of total erythrocytes (0.005-0.025 erythrocytes)

  • Infants, 1 day old: 3%-7% of total erythrocytes (0.03-0.07 erythrocytes)

  • Infants, 3 days old: 1%-3% of total erythrocytes (0.01-0.03 erythrocytes)

  • Infants, 7 days old: 0-1% of total erythrocytes (0.00-0.01 erythrocytes)

  • Infants, 1 month old: 0.2%-2% of total erythrocytes (0.002-0.02 erythrocytes)

  • Infants, 1.5 months old: 0.3%-3.5% of total erythrocytes (0.003-0.035 erythrocytes

  • Infants, 2 months old: 0.4%-4.8% of total erythrocytes (0.004-0.048 erythrocytes

  • Infants, 2.5 months old: 0.3%-4.2% of total erythrocytes (0.003-0.042 erythrocytes)

  • Infants, 3 months old: 0.3%-3.6% of total erythrocytes (0.003-0.036 erythrocytes)

  • Infants, 4 to 12 months old: 0.2%-2.8% of total erythrocytes (0.002-0.028 erythrocytes)

Ranges for normal findings may vary among different laboratories and hospitals. You should always check with your doctor after having lab work or other tests done to discuss the meaning of your test results and whether your values are considered within normal limits.

MEANING OF TEST

Your caregiver will go over the test results with you and discuss the importance and meaning of your results, as well as treatment options and the need for additional tests if necessary.

OBTAINING THE TEST RESULTS

It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.