Sysmex 2024 Fall Newsletter - Flipbook - Page 8
Hematology Case Study:
IG Present
This is a 76 year old female with a history of
chronic myelogenous leukemia, treatment
history unknown. A CBC sample analyzed on
the XN-Series™ analyzer shows a WBC count
of 46.85 x 103/µL; the automated differential
included 43.7% Immature Granulocytes (IGs).
The automated IG count on Sysmex analyzers
includes metamyelocytes, myelocytes and
promyelocytes. The WDF (WBC differential)
scattergram uses side 昀氀uorescence (SFL) to
measure nucleic acid content of the cells and
side scatter (SSC) to measure internal cellular
complexity. These immature cells have a higher
N:C ratio than mature granulocytes, which
causes them to plot higher on the y-axis. Furthermore, the primary and secondary
granules in the IGs are interpreted as increased complexity, separating these cells from
blasts which normally lack granules (blasts will be found in the “Blasts/Abn Lympho”
昀氀agging area).
The Immature Granulocyte count on Sysmex analyzers is FDA-cleared and can be a
valuable tool for physicians investigating leukocytosis in patients.
This patient presented with leukocytosis, neutrophilia and basophilia. Immature
Granulocytes (IG) are present in the automated differential although slightly lower
counts are reported using manual microscopy. Studies have shown that the manual
differential, while long considered a reference method, is subject to variations resulting
from experience of the technologist, area of the smear evaluated and smear/stain
quality. Sysmex analyzers use 昀氀uorescent 昀氀ow cytometry to provide an immature
granulocyte result which includes metamyelocytes, myelocytes and promyelocytes. The
“IG Present” message is generated based on a user de昀椀ned IG threshold. In this case, the
“Left Shift?” 昀氀ag suggests there may also be bands present.
The clinical applications or uses presented in these materials, including case studies, are provided for illustration
purposes only. Prior to using any Sysmex device, please review the manufacturer’s instructions use. It is the
healthcare provider’s responsibility to determine applicability in routine clinical practice.
8 | NEWS
