Final answer:
The observation of oligoclonal bands on CSF protein electrophoresis, but not in the serum, is indicative of multiple sclerosis. These bands suggest an intracerebral inflammatory process specific to demyelinating conditions.
Step-by-step explanation:
The observation of oligoclonal bands on CSF protein electrophoresis but not on serum protein electrophoresis is highly suggestive of an intracerebral inflammatory process. These bands represent proteins that are indicative of a local immune response within the central nervous system. The presence of oligoclonal bands in the CSF, along with a raised IgG index, is particularly specific for a demyelinating condition such as multiple sclerosis (MS).
CSF electrophoresis is conducted when there is suspicion of an inflammatory or demyelinating condition within the central nervous system. It is important to compare results with a corresponding serum sample to accurately interpret the presence of oligoclonal bands. Although oligoclonal bands can also be found in various other conditions such as Guillain-Barre syndrome or infections like neurosyphilis, their presence in the CSF and not in serum is an especially important diagnostic clue for multiple sclerosis.
In conclusion, when oligoclonal bands are identified in the CSF but not in the serum, they strongly point to multiple sclerosis as the disorder.