Which step is especially important when staining bone marrow smears with Diff-Quik?

Which step is especially important when staining bone marrow smears with Diff-Quik?

• A. Dip the smear twice as long as blood smears
• B. Use freshly filtered stain
• C. Rinse thoroughly with distilled water
• D. Let the smear dry for 30 minutes before staining

Answer: (A)

Bone marrow smears are dense and contain a wide variety of cells at different maturation stages, so staining must penetrate thoroughly to reveal morphology. Diff-Quik relies on brief, sequential dips to differentiate nuclei and cytoplasm, and marrow’s cellularity requires more dye uptake to distinguish the various precursor cells. Extending the dip time, roughly doubling what you’d use for a peripheral blood smear, helps ensure adequate staining of both nuclei and cytoplasm across all cell types, making features like chromatin patterns and cytoplasmic details visible. Without longer exposure, you can get uneven or pale staining, which hampers accurate identification and differential counts. So, increasing the immersion time specifically for bone marrow makes the important morphological distinctions clearer and more reliable.

Bone marrow smears are dense and contain a wide variety of cells at different maturation stages, so staining must penetrate thoroughly to reveal morphology. Diff-Quik relies on brief, sequential dips to differentiate nuclei and cytoplasm, and marrow’s cellularity requires more dye uptake to distinguish the various precursor cells. Extending the dip time, roughly doubling what you’d use for a peripheral blood smear, helps ensure adequate staining of both nuclei and cytoplasm across all cell types, making features like chromatin patterns and cytoplasmic details visible. Without longer exposure, you can get uneven or pale staining, which hampers accurate identification and differential counts. So, increasing the immersion time specifically for bone marrow makes the important morphological distinctions clearer and more reliable.