Clinical findings in Creutzfeldt-Jakob disease mimicking dementia with Lewy bodies.

Dr. Luís Fabiano Marin – Rua Maranhão 192 / 101 01240-000 São Paulo SP Brasil. E-mail: [email protected] Creutzfeldt-Jakob disease (CJD) is a transmissible spongiform encephalopathy or prionic disease characterized by accumulation of abnormal prionic protein (PrP) associated to spongiform degeneration of the brain. Although rare, CJD is the most common prionic disease in humans with an incidence rate around 1/1,000,000. Historically, it was first described as a dementing illness by Jakob in 1921. CJD is a rapidly progressive dementia syndrome associated to pyramidal, extrapyramidal and visual signs and symptoms. About 90% of the affected individuals develop movement disorders throughout the course of CJD and myoclonus is the most common disorder seen in 82 to 100% of cases. Other movement disorders less frequently seen include: dystonia, choreoathetosis, tremors, and parkinsonian syndrome. The rate of movement disorders increases as CJD progresses and they are less frequently seen in the early stages of disease. Parkinsonism is rarely found as an early manifestation of CJD. CJD can be classified as sporadic, genetic, iatrogenic and variant form. It is characterized by fast disease progression with a mean survival rate of four months after diagnosis. Two-thirds of patients with CJD die within six months after symptom onset. Some patients at early stages can progress to a state of akinetic mutism. Dementia with Lewy bodies (DLB) is a dementia syndrome associated to parkinsonism with little response to L-DOPA, cognitive fluctuations, visual hallucinations, and hypersensitivity to neuroleptics. It has a slower course but life expectancy is 5 to 8 years after symptom onset. DLB is the second most frequent cause of neurodegenerative dementia and its main differential diagnosis are with Alzheimer’s disease, Parkinson’s disease and some forms of atypical parkinsonism. In vivo diagnostic confirmation for both CJD and DLB is a challenge since the gold standard for their diagnosis is pathology examination. We report a case of CJD that was firstly clinically diagnosed as DLB, highlighting the occurrence of severe parkinsonian syndrome associated to neuroleptic use.