TNF and rheumatoid arthritis: The experience from the use of tumor necrosis factor (TNF) inhibitors, which are highly effective in treating autoimmune rheumatic diseases like RA, is that they increase the risk of developing inflammatory demyelinating CNS events [15]. While well-reported with TNF inhibitors, transverse myelitis and other neurologic complications, like CNS demyelination from abatacept, are unreported [14,16].