OCB

Description: Oligoclonal bands (OCBs) represent discrete bands of immunoglobulins detected in the CSF separated by isoelectric focusing. OCBs can result from systemic sources, in which case identical bands will appear in both CSF and serum. When unique bands are present only (or in greater number) in CSF, it is suggestive of intrathecal immunoglobulin synthesis, and consistent with Multiple Sclerosis (MS). OCBs are present in approximately 90% of confirmed MS cases but have also been observed to a lesser extent in other neurological diseases such as Neuromyelitis Optica Spectrum Disorders (NMOSD) and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD). 

Test Indications: Initial suspicion of MS generally arises because of clinical symptoms or MRI findings. OCB testing may provide further diagnostic evidence, especially when clinical findings indicate features of atypical MS or are inconsistent with a clinically isolated syndrome. It may also provide additional diagnostic assistance for populations in which MS is less likely, such as the elderly or in children.

Register both serum and CSF specimens under OLIG test code.

Interpretation & Assay Interferences: When the oligoclonal band assay detects 2 or more unique IgG bands in the cerebrospinal fluid, the result is positive; however, a positive result alone is not diagnostic for MS. Clinical correlation recommended.