To the Editor We read with interest an article published by Gelfand et al.1 The authors presented their institutional series of 49 patients who were given the initial diagnosis of encephalitis, not otherwise specified (ENOS) on pathologic review. For the 29 patients whose original pathologic material was available for review, subsequent neuropathologic review led to a more specific categorization in 34%. Among the 19 patients who still had ENOS after additional neuropathologic review, a definite diagnosis was reached in 32% based on ancillary testing, subsequent clinical information, and clinical follow-up. The authors concluded that it may be worthwhile to have the biopsy materials reviewed again because an original diagnosis of ENOS could be classified into a more specific disease category in a third of the cases.
Wang Z, Lancaster E, Yang L. Diagnosing Encephalitis, Not Otherwise Specified. JAMA Neurol. 2015;72(6):725. doi:10.1001/jamaneurol.2015.0542