Bence Jones proteinuria

This code indicates the presence of Bence Jones proteins in the urine, which are monoclonal light chains produced by plasma cells. Their detection is a key diagnostic marker for plasma cell dyscrasias, most notably multiple myeloma. This finding signifies an underlying hematologic malignancy or other lymphoproliferative disorder.

Assign this code when laboratory tests, such as urine protein electrophoresis (UPEP) or immunofixation electrophoresis (IFE), confirm the presence of Bence Jones proteins. It is typically used in the workup or monitoring of patients with suspected or diagnosed multiple myeloma, amyloidosis, or other monoclonal gammopathies. Documentation should clearly state the positive finding of Bence Jones proteinuria.

• Always code the underlying condition (e.g., multiple myeloma, C90.00) first, as Bence Jones proteinuria is a manifestation.
• Do not confuse with general proteinuria (R80.1, R80.2) or other specific types of proteinuria unless Bence Jones proteins are explicitly identified.
• Ensure the documentation specifies "Bence Jones" to differentiate from other types of monoclonal gammopathy of renal significance.