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A 64-year-old man is referred to you from the pulmonary clinic where he has been seen for a series of upper respiratory infections in the last 6 months.
There is no lymphadenopathy, but you note splenomegaly, 4 cm below the LCM. The WBC was 25.0 x109/L with a differential of 75 lymphocytes, 13 monos, 7 segs, 3 eos, 2 basos. These lymphocytes are slightly larger than the usual small lymphocyte.
The lymphocytes are CD19-, CD5-, CD3+, CD8+ and CD56+.
With the results of this information you suggest the following as the most likely diagnosis:
A. Chronic lymphocytic leukemia
B. Prolymphocytic leukemia
C. T gamma lymphocytosis
D. Pertussis
E. Infectious mononucleosis
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I would think B since lymphocytes are enlarged, and don't think in CLL WBC are so high.
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it should not be A since CD19 -.
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C. T gamma Leukocytosis; Its a kind of skin cancer. monoclonal proliferation of cytotoxic T cells.
CD19- , No, B cells
CD 3+ , SO, all T cells
CD 8 AND 56 are marker of cytotoxic T cells.
Can anybody send me NBME2 question. I can provide my best answer.
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In this case the lymphocytes are Tcells (CD3+) and are T suppressors (CD8+) but they are CD5- an unusual finding if normal Tcells.
Chronic lymphocytic leukemia is usually a B cell (CD19+) coexpressing CD5.T-cell CLL is CD3+ and almost always a T-helper (CD4+) phenotype.
Prolymphocytic leukemia has a similar phenotype to that of CLL and would generally present with a higher white count.
**T gamma lymphocytosis best fits the phenotypic (CD3-, CD5-, CD8+, CD56+) and clinical data (splenomegaly; moderately elevated WBC count; arthritis & neutropenia) and is probably a proliferation of T-NK cells.
Pertussis and infectious mononucleosis elicit reactive lymphocytoses where most of the lymphocytes are atypical in appearance and have a typical T suppressor phenotype (both CD3 and CD5 are positive as well as being CD8+).
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thanks for the detailed information. That helps a lot.
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Where do you get this q? I found desparity between age of the pt and B-cell def.
B-cell deficient pt (like Omenn syndrome) can not survive without Rx usually transplantation .
