This document discusses histograms generated by cell counters. It provides 3 key points: 1) Histograms graphically represent the numerical distribution of different cell populations based on cell size, with the y-axis being cell count and x-axis being cell size. 2) A normal red blood cell histogram shows a Gaussian bell-shaped curve with the peak falling within the normal mean corpuscular volume range of 80-100 fL. 3) Abnormal histograms can reveal conditions like iron deficiency, transfusion, or extreme leukocytosis based on multiple peaks or shifts in the normal distribution. Potential causes for flags are also outlined. Case studies then provide examples of interpreting abnormal histograms.

1. HISTOGRAMS
Dr.Evith Pereira
Moderator : Dr.Shilpi Sahu
29/04/2016

2. PRINCIPLE OF CELL COUNTER
Electronic Impedance
• Wallace coulter
• Passage of cell displaces the volume of diluent
and this increases resistance
• Impulse are generated due to difference in
potential at two electrodes which is read at
oscilloscope
• Number of impulse indicate number of cells and
height indicates volume of cells

3. Optical light scatter
• A diluent suspension flows through a aperture so
that the cells pass in a single file in front of light
source
• Light is scattered by the cells passing through the
light beam
• The amount of light scatter is detected by
photomultiplier and photodiodes
• Electrical impulse are generated for counts

4. HISTOGRAMS
• These are the graphical representation of
numerical data of different cell population on
cell counter.
• Y axis represents the number of cells and X
axis represents the cell size.

6. Normal RBC Histogram
• Normal RB distribution curve is a Gaussian bell
shaped curve.
• Peak of curve falls between the normal range of
MCV 80 – 100 fl.
• MCV is perpendicular line from peak of the curve
to the base.
• There are two flexible discriminators LD ( 25-75
fl) and UD ( 200 – 250 fl)

12. Possible causes:
• RBC agglutination
• Small lymphoid cells present in high number -
CLL

13. MULTIPLE PEAKS
Possible causes:
• Iron deficiency in
recovery
• Post transfusion
• Extreme leukocytosis

14. Thrombocyte Histogram

16. PL FLAG
Possible causes:
• Cell fragments
• Contaminated reagents
• High number of bacteria
PU FLAG
Possible causes:
• EDTA clumps.
• Giant platelets
• Micro-erythrocytes
• Fragmented / dysplastic
RBCs.

17. WBC HISTOGRAM

22. Neutrophilia

23. Lymphocytosis

24. MONOCYTOSIS EOSINOPHILIA

25. CASE STUDIES

26. CASE 1

27. CASE 2

28. CASE 3

29. CASE 4

30. CASE 5