Distinct oligoclonal bands in the γ region on CSF protein electrophoresis are diagnostic of which disease?

Distinct oligoclonal bands in the γ region on CSF protein electrophoresis are diagnostic of which disease?

• A. Multiple sclerosis
• B. Multiple myeloma
• C. Waldenström's macroglobulinemia
• D. Myoglobinemia

Answer: (A)

Oligoclonal bands in the gamma region of CSF electrophoresis reflect intrathecal production of IgG by plasma cells within the central nervous system. This pattern—several distinct narrow bands that are present in the CSF but not in the serum—is a hallmark of multiple sclerosis, indicating immune activity directed at the CNS. The finding is used as supportive evidence in MS because it shows that IgG synthesis is occurring inside the CNS rather than being derived from the bloodstream. The other conditions don’t fit this pattern. Multiple myeloma and Waldenström’s macroglobulinemia involve monoclonal immunoglobulins produced systemically, typically seen as a single dominant band (an M-spike) in serum rather than the multiple discrete intrathecal bands seen in MS. Myoglobinemia involves muscle injury with myoglobin release, not immunoglobulin patterns in CSF.

Oligoclonal bands in the gamma region of CSF electrophoresis reflect intrathecal production of IgG by plasma cells within the central nervous system. This pattern—several distinct narrow bands that are present in the CSF but not in the serum—is a hallmark of multiple sclerosis, indicating immune activity directed at the CNS. The finding is used as supportive evidence in MS because it shows that IgG synthesis is occurring inside the CNS rather than being derived from the bloodstream.

The other conditions don’t fit this pattern. Multiple myeloma and Waldenström’s macroglobulinemia involve monoclonal immunoglobulins produced systemically, typically seen as a single dominant band (an M-spike) in serum rather than the multiple discrete intrathecal bands seen in MS. Myoglobinemia involves muscle injury with myoglobin release, not immunoglobulin patterns in CSF.