An unusual association between HIV and Creutzfeldt-Jakob disease in a patient from northeastern Brazil.

Prion diseases are significant contributors to rapidly progressive dementia. Among these conditions, sporadic Creutzfeldt-Jakob Disease (CJD) is the most prevalent, characterized by its rarity, lack of treatment options, and rapid progression to fatality. Diagnosis relies on a combination of clinical symptoms and specific alterations detected in brain MRI, EEG, and CSF analysis. The present study details the case of a 53-year-old individual from Fortaleza, Brazil, diagnosed with sporadic CJD, confirmed through clinical presentation and a series of diagnostic evaluations, including 14-3-3 protein detection and RT-QuIC analysis. Differential diagnoses were considered to rule out other rapidly progressing conditions, such as infectious and immune-related diseases, ultimately leading to a likely diagnosis of sporadic CJD.