Which disorder involves rapidly progressing dementia and is often misdiagnosed as Alzheimer's disease?

Creutzfeldt-Jakob disease (CJD) is characterized by rapidly progressing dementia and is often misdiagnosed as Alzheimer’s disease due to some overlapping symptoms, such as memory loss and cognitive decline. CJD is a prion disease, which leads to the degeneration of brain tissue and presents with not only dementia but also neurological symptoms such as personality changes, hallucinations, and motor dysfunction. The speed of progression—typically within months—is much faster than that of Alzheimer's disease, which generally progresses over several years. This rapid decline can lead to confusion in diagnosis, especially in the earlier stages when patients may primarily present with memory issues.

In contrast, Huntington's disease, frontotemporal dementia, and Parkinson's disease exhibit different patterns of symptoms, rates of progression, and neurological features, making them less likely to be mistaken for Alzheimer’s in the same way. For example, while frontotemporal dementia can also cause changes in personality and behavior, its early symptoms can be more distinctive than those seen in Alzheimer’s, helping to differentiate the two conditions.