<prompt> Two or more oligoclonal bands in cerebrospinal fluid are most often positive in-Acute bacterial meningitisMultiple sclerosisSubarachnoid harmorrhagePolyneuropathy  <response>: Oligoclonal bands OCBs are bands of immunoglobulins that are seen when a patients blood serum, or cerebrospinal fluid CSF is analyzed. They are used in the diagnosis of various neurological and blood diseases, especially in multiple sclerosis. The blood serum can be gained from a clotted blood sample. Ref Davidson 23rd edtion pg 450 