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Histology, microscopy, anatomy and disease
Histology, microscopy, anatomy and disease

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3.4 Identify an abnormality – part I

In the next activity you will be using the virtual microscope again.

Activity 4

Open the virtual microscope [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] in a new window or tab.

Carry out a differential leukocyte count on the blood smear shown on Slide 5 in the ‘Week 1’ category within the virtual microscope.

Consider these questions. You may find it helpful to refer to Figure 12 showing the appearance of the cells and Table 1 showing the relative abundance of different types of leukocyte.

  • Is the differential blood count within the normal range?
  • Do the lymphocytes appear normal?
  • What is the diagnosis of this condition?
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The following conclusions can be drawn from analysis of Slide 5:

  • The differential blood count is not within the normal range. There are very large numbers of lymphocytes in the smear.

  • Additionally, the lymphocytes do not appear normal. The cells and their nuclei have an irregular shape.

  • The diagnosis of this condition is a chronic lymphocytic leukaemia: the blood contains very high numbers of abnormal lymphocytes.

How did you get on? Did you manage to derive the same conclusions? Also, please don’t worry if you were not able to derive all of these answers – it requires a certain amount of practice to count cells and draw conclusions from your observations. The next activity provides another opportunity for you to develop your skills in this area.