Question

A 10-year-old girl was brought to an outpatient clinic because she complained of sore throat and a lump in her neck. On examination, she was observed to have a tonsillar abscess, swollen glands, and widespread bruising in the extremities. She also had a low-grade fever. She was treated with antibiotics and released, but she failed to progress over the next 2 days. Hematology laboratory tests revealed a WBC of 8.0 x 10^9/L, a hematocrit of 28%, and a platelet count of 10 x 10^12/L peripheral blood differential count revealed 3 band neutrophils, 25 segmented neutrophils, 8 lymphocytes, 1 monocyte, and 63 blasts.

The patient’s parents were contacted, and the girl was immediately admitted to the hospital. A bone marrow examination was performed and revealed an infiltration of blast cells in the marrow.

Immunophenotyping was performed on the bone marrow cells. The results show the cells have CD 11b, CD 13, CD 33, and CD15 markers.

1. Why are the hematocrit and platelet count decreased?

2. What is immunophenotyping and why is it an important test?

3. What is the most likely diagnosis based on these test results?

4. How would the results differ in the immunophenotying of the cells had CD 10, CD 19, CD 20 and CD 22 markers?

Answer 1

Answer of Question Number 2-:

• Immunophenotyping is a technique used to identify certain cells by labelling them with a fluorescent dye using antibodies specific to some antigens (markers) of that cell.
• These markers are usually function on membrane proteins involved in cell communication, adhesion or metabolism.
• Immunophenotyping often coupled with flow cytometry has become an method of identifying and sorting cell with in complex population for example The analysis of immune cells in a blood sample.
• It can also used in bone marrow samples .
• Immunophenotyping is commonly used to analyze and sort T - lymphocyte into substance based on CD antigens by the techique of flow cytometry.
• It classifying cells of the immune system based on structural and functional difference.
• It distinguish between hematogens and B - lymphoblasts .

Hematogens are normal B - lineage lymphoid precusers in the bone marrow and B - lymphoblasts are immature neoplastic cells present in patient with precutpre B- cells acute lymphoblastic leukemia.