Diagnosis
Establishing a diagnosis of MS is not always straight forward as it is extremely variable in presentation, which may be monosymptomatic or polysymptomatic. The symptoms at presentation (Box 1) may result in a person being referred to a number of different clinicians before a neurological opinion is sought. The first episode of demyelination might well be an isolated attack. The McDonald criteria are used internationally in the diagnosis of MS (McDonald et al, 2001). However, there is no specific single test to confirm diagnosis; it is based on the following:
● History;
● Clinical (neurological) examination;
● Evoked potentials (usually visual); ● Magnetic resonance imaging; ● Lumbar puncture.
If an MRI scan shows plaques where demyelination has occurred, lumbar puncture might not be necessary.
If there is uncertainty about the diagnosis, a sample of cerebrospinal fluid will be taken. Oligoclonal bands are