Rapid distinction of acute demyelinating disorders and central nervous system lymphoma by molecular analysis of cerebrospinal fluid cells

Polymerase chain reaction (PCR) based automated high-resolution fragment analysis of rearranged immunoglobulin heavy-chain genes is a highly sensitive means for identifying clonal B-cell responses. We used this technique to distinguish polyclonal inflammatory from monoclonal neoplastic B-cell populations in the cerebrospinal fluid (CSF) of three patients with acute demyelinating disorders of the central nervous system whose clinical, magnetic resonance imaging (MRI) and CSF features did not permit unequivocal exclusion of primary central nervous system lymphoma (pC-NSL). This approach is highly suitable for detecting CNS inflammation particularly when lymphomatous involvement cannot be ruled out by noninvasive diagnostic procedures alone.