Status dystonicus in adult patients with anti-N-methyl-D-aspartate-acid receptor encephalitis.

Abstract

Status dystonicus (SD) is a severe movement disorder (MD) and has rarely been recognized in anti-N-methyl-D-aspartate-acid receptor (NMDAR) encephalitis, particularly in adult patients. We aim to explore the clinical characteristics and outcome of SD in anti-NMDAR encephalitis. Patients with anti-NMDAR encephalitis admitted to Xuanwu Hospital from July 2013 to December 2019 were prospectively enrolled. SD was diagnosed based on the patients' clinical manifestations and video EEG monitoring. Outcome was evaluated 6 and 12months after enrollment using the modified Ranking Scale (mRS). A total of 172 patients with anti-NMDAR encephalitis, including 95 males (55.2%) and 77 females (44.8%) with a median age of 26years (interquartile range 19 to 34) were enrolled. Eighty patients (46.5%) presented with movement disorder (MD), 14 of whom suffered from SD, which manifested as chorea (14/14, 100%), orofacial dyskinesia (12/14, 85.7%), generalized dystonia (8/14, 57.1%), tremor (8/14, 57.1%), stereotypies (5/14, 35.7%), and catatonia (1/14, 7.1%) of the trunk and limbs. All SD patients exhibited disturbed consciousness and central hypoventilation, requiring intensive care. SD patients also had high cerebrospinal fluid NMDAR antibody titers, a higher proportion of ovarian teratoma, higher mRS scores upon enrollment, longer duration to recover, and poorer outcomes at 6 (P < 0.05) but not at 12months as compared to non-SD patients. SD is not uncommon in anti-NMDAR encephalitis patients and relates to the severity and worse short-term outcome of the anti-NMDAR encephalitis. Early recognition of SD and timely treatment is important to shorten the time needed for recuperation.