Creutzfeldt-Jakob Disease Mimicking Neurosyphilis: A Complex Presentation, Histopathological Findings, and Special Precautions for Autopsy.

Creutzfeldt-Jakob disease (CJD) is a complex and rapidly fatal prion infection of the central nervous system with characteristic clinical and pathological findings. Herein, we present the case of an 80-year-old man with a 2-month history of rapid cognitive decline and ataxic gait. He was found to have a positive rapid plasma reagin and fluorescent treponemal antibody absorption (FTA-ABS) upon clinical testing and was presumed to have neurosyphilis. His neurological status precipitously declined during his hospitalization and he died. A complete autopsy was performed, which revealed diffuse spongiform change throughout the cerebrum. Brain tissue was sent to the National Prion Disease Surveillance Center, where immunostaining for prion protein (3F4) showed granular deposits, confirming the diagnosis of CJD. There have been rare cases reported in which CJD was clinically suspected but neurosyphilis was confirmed at autopsy. To our knowledge, this is the first case to be published in which the clinical findings strongly favored neurosyphilis, but spongiform encephalopathy was identified at autopsy. We review the clinical, radiographic, electrophysiological, laboratory, and histopathological features of both diseases and discuss the overlapping findings and inherent diagnostic difficulties. We also review the recommended protocols for safely handling suspected prion-infected autopsy tissue. A heightened awareness of the features of CJD and other prion diseases is needed among forensic pathologists, neuropathologists, and general autopsy pathologists to understand how to safely handle the tissue to get definite diagnoses for the decedent's family members and clinical care team.