To the Editor Grau-Rivera et al1 reported that in their study, none of the 49 patients with definite Creutzfeldt-Jakob disease (CJD) revealed antibodies against neuronal surface antigens, including N-methyl-D-aspartate receptors (NMDARs), in the cerebrospinal fluid (CSF). In this article, they referred to previous studies2,3 and criticized that anti-NMDAR antibodies in patients with CJD had been reported in the serum alone and that analysis of CSF antibodies should be included to avoid potential pitfalls. However, we demonstrated that one of the patients with sporadic CJD, positive for abnormal prion protein (PrPSc) in CSF according to real-time quaking-induced conversion, had CSF antibodies against NMDAR examined with a cell-based assay using human embryonic kidney 293 cells cotransfected with NR1 and NR2 cDNA.4 Therefore, CSF antibodies against NMDAR do not always rule out the diagnosis of CJD.
Fujita K, Tanaka K, Takahashi Y. Neuronal Antibodies in Creutzfeldt-Jakob Disease. JAMA Neurol. 2014;71(4):514. doi:10.1001/jamaneurol.2014.27