Pathology · single question
A Bence Jones protein test used in the workup of multiple myeloma is performed on which specimen?
Show answer and explanation
Correct answer: B. Urine
- A. CSF has no role in myeloma diagnosis.
- B. Correct. BENCE JONES PROTEINS are free monoclonal immunoglobulin LIGHT CHAINS. They are small enough to be filtered by the glomerulus and therefore appear in the URINE, detected by urine protein electrophoresis and immunofixation. Their classic historical property was precipitating on heating to around 60 degrees and redissolving on boiling. They are a major contributor to the renal failure seen in myeloma.
- C. Serum protein electrophoresis detects the M-spike in blood, but Bence Jones proteins specifically are a URINE finding.
- D. Bone marrow aspiration demonstrates the plasma cell infiltrate (over 10% plasma cells) but is not the Bence Jones test.