title: 'Benign' ovarian teratoma and N-methyl-D-aspartate receptor (NMDAR) encephalitis in a child.
abstract: N-methyl-D-aspartate receptor (NMDAR) encephalitis is a life-threatening paraneoplastic neuropsychiatric encephalitis that predominantly affects young women and has a strong association with ovarian teratomas. Removal of the ovarian teratomas improves the prognosis and decreases the risk of recurrence. We present an 11-year-old girl with NMDAR encephalitis with small bilateral teratomas not initially appreciated on abdominal CT or pelvic MRI. A 12-mm teratoma was identified in the right ovary and a 7-mm teratoma was identified in the left ovary on US follow-up at 5 months. Intraoperative sonography was used to localize the teratomas for excision. In NMDAR encephalitis, the ovarian teratomas can be very small, particularly in children, and easily missed on cross-sectional imaging. Awareness of the association of NMDAR encephalitis and ovarian teratomas will improve the diagnostic accuracy and imaging interpretation. Periodic sonography and MRI might be warranted in children if the initial study is negative.
authors: Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. kieran_frawley@health.qld.gov.au
authors: Kieran J
authors: KJ
authors: Frawley
authors: Maria A
authors: MA
authors: Calvo-Garcia
authors: Darcy A
authors: DA
authors: Krueger
authors: Richard L
authors: RL
authors: McMasters
references: Ann Neurol. 2009 Jul;66(1):11-8
references: 19670433
references: Neurology. 2008 Feb 12;70(7):504-11
references: 17898324
references: Brain. 2010 Jun;133(Pt 6):1655-67
references: 20511282
references: Ann Neurol. 2007 Jan;61(1):25-36
references: 17262855
references: Seizure. 2011 Apr;20(3):266-70
references: 21146427
references: Neurology. 2010 Nov 9;75(19):1735-9
references: 21060097
references: Ann Neurol. 2005 Oct;58(4):594-604
references: 16178029
references: Lancet Neurol. 2008 Dec;7(12):1091-8
references: 18851928