Master the board step 3

Hematology
Diagnostic Testing
Initial testing is as follows:
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Skeletal survey to detect punched out osteolytic lesions. (Osteoblastic
lesions suggest metastatic prostate cancer.)
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Serum protein electrophoresis (SPEP): You are looking for elevated levels
of monoclonal antibody (usually IgG). 20% are IgA.
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Urine protein electrophoresis (UPEP): Detects Bence-Jones protein.
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Peripheral smear: Shows “rouleaux” formation of blood cells. Mean platelet
volume (MPV) is elevated because the cells stick together.
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Elevated calcium level: Makes sense with the osteolytic lesions.
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Beta 2 microglobulin level: This is a prognostic indicator.
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BUN and creatinine: This is to detect the frequent occurrence of renal insufficiency.
Bortezomib reverses renal dysfunction.
Basic Science Correlate
Mechanism of Renal Failure in Myeloma
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Hypercalcemia leads to nephrocalcinosis.
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Hyperuricemia is directly toxic to kidney tubules.
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Bence-Jones protein clogs up glomeruli and is toxic to kidney tubules.
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Amyloid occurs in myeloma.
The single most specific test is the bone marrow biopsy, which detects high
numbers of plasma cells (10 percent).
The B12 and LAP levels are
elevated in Pvera.
“Rouleaux” formation of blood cells
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