Abstract
Creutzfeldt-Jakob disease (CJD) is a rare, rapidly progressive, and fatal neurodegenerative disorder caused by abnormal prion proteins. Due to its often nonspecific and variable early symptoms, CJD is frequently misdiagnosed as a psychiatric or other neurodegenerative condition, creating significant diagnostic challenges. Timely recognition is crucial but remains difficult due to its rarity and overlap with more common disorders. We describe a 66-year-old male patient who was initially admitted to a psychiatric unit with prominent behavioral disturbances and mood changes. The clinical presentation was initially attributed to a primary psychiatric illness, particularly bipolar disorder. Brain imaging and electroencephalogram (EEG) were inconclusive. However, cerebrospinal fluid (CSF) analysis revealed findings consistent with prion disease, confirming the diagnosis of CJD. The patient's neurological function deteriorated rapidly, and he died within two months of diagnosis. This case highlights the diagnostic complexity of CJD, especially in its early stages when psychiatric symptoms may predominate. A high index of suspicion and early use of CSF biomarkers are essential for timely diagnosis. Clinicians should consider CJD in the differential diagnosis of rapidly progressive neuropsychiatric syndromes, as early recognition, although not curative, can guide appropriate care and family counseling.