Corrected Reticulocyte Count for Hct (Reticulocyte Index)

 

Calculate the RI (corrected reticulocyte count for degree of anemia)

 

reticulocyte index = corrected reticulocyte count for anemia =

= (observed reticulocyte count, as a percent) * (patient's hematocrit) / 45 / 1%

 

where:

• The patient's hematocrit is taken as a whole number.

• The denominator 45 represents the normal hematocrit.

• The denominator 1% indicates the normal reticulocyte count; division by 1% also allows the reticulocyte count to appear as a whole number.

 

Limitations:

• Manual reticulocyte counts have a relatively high counting error. This can be reduced by the use of counting reticulars in the ocular lens of the microscope.

 

Questions:

• Is the equation appropriate for use in situations where hematocrits are > 45%, as is seen in newborns?