What is the next step after a monoclonal gamma region is observed on serum protein electrophoresis?

What is the next step after a monoclonal gamma region is observed on serum protein electrophoresis?

• A. Immunofixation electrophoresis
• B. Serum protein electrophoresis
• C. Flow cytometry
• D. Western blot

Answer: (A)

When a single sharp monoclonal spike appears in the gamma region, the goal is to identify exactly what immunoglobulin is causing it. Immunofixation electrophoresis does this by separating serum proteins and then applying antisera specific for the heavy-chain classes (IgG, IgA, IgM) and for light chains (kappa, lambda). The pattern that develops shows which heavy chain and light chain are present, confirming monoclonality and providing the precise type of M-protein. This typing is essential for diagnosis, prognosis, and tracking response to therapy. Repeating a standard serum protein electrophoresis wouldn’t reveal the immunoglobulin class or light-chain type. Flow cytometry analyzes cells rather than serum proteins, so it isn’t used to identify the M-protein in this context. Western blot is not the routine method for typing serum monoclonal proteins and is less practical for this purpose.

When a single sharp monoclonal spike appears in the gamma region, the goal is to identify exactly what immunoglobulin is causing it. Immunofixation electrophoresis does this by separating serum proteins and then applying antisera specific for the heavy-chain classes (IgG, IgA, IgM) and for light chains (kappa, lambda). The pattern that develops shows which heavy chain and light chain are present, confirming monoclonality and providing the precise type of M-protein. This typing is essential for diagnosis, prognosis, and tracking response to therapy.

Repeating a standard serum protein electrophoresis wouldn’t reveal the immunoglobulin class or light-chain type. Flow cytometry analyzes cells rather than serum proteins, so it isn’t used to identify the M-protein in this context. Western blot is not the routine method for typing serum monoclonal proteins and is less practical for this purpose.