A 68 year old man

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A 68 year old man

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jean robert
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05/18/08 - 01:08 AM

A 68 yr old man presents to his physician with complaints of fatigue and dragging sensation in his abdomen. PE is remarkable for massive splenomegaly without lymphadenopathy. The patient s hematocrit is 30%, his platelet count is 80,000/mm3 , and his leukocye count is 2500/mm3. Bone marrow biopsy shows "fried egg" cells expressing the pan B-cell markers CD19 AND CD20, and monocyte marker CD11c. positive staining for which of the following substances would most likely verify the likely diagnosis?

a) CD4

b) GpIIb/IIIa

c) Myeloperoxidase

d) Nonspecific esterase

e) Tartrate- resistant acid phosphatase

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new_n_lost
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05/18/08 - 01:57 AM

e) Tartrate- resistant acid phosphatase

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Tiff
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05/18/08 - 08:42 AM

Agree - Hairy Cell - Choice E

jean robert
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05/19/08 - 01:02 AM

new_n_lost wrote:
e) Tartrate- resistant acid phosphatase

EXPLANATION

Hairy cell leukemia is characterized by Pancytopenia and Splenomegaly. Lymphadenopathy is unusual. The proliferating cells express the pan B-cell markers (CD19 and CD20), the monocyte marker (CD11c), the IL-2 receptor (CD25), plasma cell -associated antigen-1(PCA-1). Histologically, the cells display fine, hairlike projections when viewed with phase-contrast microscopy. A " fried-egg" appearance on stained bone marrow biopsy arises because of fixation artifacts that occur as a result of the hairlike projections on many of the cells. Tartrate-resistant acid phosphatase is virtually diagnostic of hairy cell leukemia.

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