Case of the Month

Section Editor: Nicholas Stence, MD
Children's Hospital Colorado, Aurora, CO

OCTOBER 2012

Next Case of the Month coming November 5...

NMDA Receptor Antibody-Associated Encephalitis

Paraneoplastic encephalitis associated with N-methyl-D-aspartate (NMDA) receptor antibodies in the setting of a teratoma, which is usually ovarian.
CSF and serum are positive for NMDA receptor IgG antibodies; inflammatory changes in CSF.
All other diagnostic tests for source of encephalitis are negative.
Patients frequently have psychiatric symptoms, autonomic instability, and seizure, which can be life-threatening.
Key Diagnostic Features: Cerebral edema, T2/FLAIR signal abnormalities +/- transient meningeal enhancement. Distribution is not specific but commonly involves the medial temporal lobes.
DDx: other encephalitides (viral, autoimmune, limbic), status epilepticus, global anoxic, or other toxic/metabolic injury
Rx: teratoma removal, immunotherapy, respiratory support

Suggested Reading

Sansing LH, Tüzün E, Ko MW, et al. A patient with encephalitis associated with NMDA receptor antibodies. Nat Clin Pract Neuro 2007;3:291-6. doi: 10.1038/ncpneuro0493

Vitaliani R, Mason W, Ances B, et al. Paraneoplastic Encephalitis, Psychiatric Symptoms, and Hypoventilation in Ovarian Teratoma. Ann Neurol 2005;58:594-604. doi: 10.1002/ana.20614

Stein-Wexler R, Wootton-Gorges SL, Greco CM, et al. Paraneoplastic limbic encephalitis in a teenage girl with an immature ovarian teratoma. Pediatr Radiol 2005;35:694-97. doi: 10.1007/s00247-005-1402-1