Patient exclusion: A patient with congenital Pelger-Huet anomaly.
The ppp can be determined on either the bone marrow or the peripheral blood smear. The ppp for bone marrow and peripheral blood show a linear relationship, as shown in Figure 3 (Widell et al, page 118).
Pelgeroid nuclei:
(1) monolobated
(2) bilobated with straight connecting strand (dumbbell-shaped)
(3) bilobated with curved connecting strand (band-like)
The connecting strand in bilobated forms must be less than one third of the total width of the nucleus.
percent pelgeroid polymorphs =
= (number of neutrophils with a pelgeroid nucleus) / (number of neutrophils counted) * 100%
Interpretation:
• The normal ppp is <= 5%.
• The higher the ppp the greater the degree of bone marrow dysplasia.
• A ppp >= 20% tends to be seen in patients with bi- or tri-lineage dysplasia in the bone marrow.
