Hi, Heather. Oligoclonal bands are significant if they appear in the spinal fluid but not in the blood serum, meaning that the disorder is in the central nervous system. Usually just one band is discounted, and two or more can point to MS. However, there are schools of thought that insist on at least 4 bands.
MS is not the only disease involving these O-bands. Wikipedia lists these others:
Devic's disease
Systemic lupus erythematosus
Neurosarcoidosis
Subacute sclerosing panencephalitis
Subarachnoid haemorrhage
Syphilis
Primary central nervous system lymphoma
Quix has written a lot about CIS turning into MS. Here is a link:
http://www.medhelp.org/posts/Multiple-Sclerosis/CIS---THE-CLINICALLY-ISOLATED-SYNDROME/show/1138131
ess