Epidemiology of Neuropsychiatric Systemic Lupus Erythematosus

A variety of neuropsychiatric manifestations are observed in patients with SLE. The American College of Rheumatology (ACR) developed standardized nomenclature and case definitions for neuropsychiatric involvement in SLE (NPSLE) in 1999. One of the problems in the 1999 ACR classification is the inclusion of milder, less specific and more subjective manifestations such as headache, mild cognitive dysfunction and mood disorders, which resulted in an enormous variation in the prevalence between studies. Another critical point of the ACR classification is the lack of a number of other neurological manifestations, such as neuromyelitis optica spectrum disorders and reversible focal neurological deficits mimicking cerebrovascular disease. Steroid psychosis is sometimes a difficult differential diagnosis, but not necessarily an exclusion, of lupus psychosis. CSF IL-6 might be one of the surrogate markers to detect patients with headache, cognitive dysfunction and mood disorders, requiring immunosuppressive therapy.