Module overview
Section 1 of 6 · Open sections

Required section · Section 1 of 6

An in-range MCV with an RBC distribution flag

An adult outpatient K2-EDTA specimen was collected at 09:10, analyzed at 10:05, and reviewed at 10:18 after an RBC distribution flag. The RBC count is 3.92 × 10^12/L, hemoglobin is 10.8 g/dL, and hematocrit is 34.3%. MCV is 87.5 fL, within this case's illustrative interval of 81.0 to 99.0 fL. An average does not show whether the cells are uniform.

The volume histogram is broad with peaks near 70 fL and 98 fL. In a representative monolayer, microcytic hypochromic cells coexist with a discrete normocytic population. Dimorphism means two discernible red-cell populations; continuous anisocytosis is a broad continuum of size variation rather than two separable populations. RDW alone cannot establish either pattern.

A size or color description is an observation, not a diagnosis. Confirm that the field represents the specimen, name the morphology with approved local terms, and reconcile it with indices and analyzer evidence.

Guided CBC and smear data
ResultValueIllustrative interval or evidence
RBC count3.92 × 10^12/L4.0-5.2 × 10^12/L, low
Hemoglobin10.8 g/dL12.0-16.0 g/dL, low
Hematocrit34.3%36.0-46.0%, low
MCV87.5 fL81.0-99.0 fL, in range
MCHC31.5 g/dL32-35 g/dL, low
RDW-CV19.8%11.5-14.5%, high local illustrative interval
Reticulocytes2.8%0.5-2.0%, high local illustrative interval
HistogramPeaks near 70 and 98 fLBroad, bimodal distribution flag

Knowledge checks

Reading and checks are open. Sign in only to save.

Knowledge check 1

Which finding best explains why the MCV of 87.5 fL cannot be read as uniform normocytosis in this case?

Choose one option.

Section status

Finish this section

Reading and checks are open. Sign in only to save.

The module finishes after every required section is marked done and every check in those sections is correct.