IL6 and myalgic encephalomeyelitis/chronic fatigue syndrome: The level of IL-6 observed in CFS is higher in NPSLE patients with an acute confusional state (ACS), which includes anxiety disorders, cognitive dysfunction, mood disorders, and psychosis, relative to those with diffuse NPSLE, states other than ACS, or those with focal NPSLE, which suggests that the IL-6 level observed in CFS may indicate the severity of NPSLE (64, 65).