Case Report of a pathologically confirmed vascular parkinsonism with early cognitive impairment and Behavioral disturbance

BACKGROUND: Vascular Parkinsonism(VaP) is defined as parkinsonism resulting from cerebral vascular disease(CVD), with presence of variable motor and non-motor signs that are corroborated by clinical, anatomic or imaging findings of cerebrovascular disease. Overlapping syndromes with mixed pathologies make VaP difficult to distinguish from primary neurodegenerative parkinsonism.To understand the clinical and pathological features of VaP,we report a case of autopsy confirmed vascular Parkinsonism that was clinical misdiagnosed as idiopathic Parkinson’s disease.Clinical features include early mixed symptoms of dementia,behavioral disturbance and parkinsonism that were similar to Dementia with lewy Body(DLB) and Parkinson disease Dementia(PDD). CASE PRESENTATION: A 84-year-old man presented progressive parkinsonism with prominent postural instability, gait impairment, pseudobulbar, early cognitive impairment, irritability, hallucination, urinary symptoms and poor responsiveness to dopaminergic drugs. He was clinically diagnosed as Parkinson disease(PD). In the post-mortem study, we examined Aβ and phospho-tau as pathological biomarker for Alzheimer’s disease(AD), α-synucleing in medulla, pons and midbrain for PD and DLB. Hematoxylin and eosin staining in cerebral cortex, cerebellum and brainstem examines vascular pathological changes and microvascular lesion.Neither Lewy bodies in the substantia nigra ,locus ceruleus and cerebrumnor accumulation of Aβ, neurofibrillary tangles were noted. Instead, there were many cerebral infarctions and widespread arteriosclerosis in the brain. The final brain autopsy supported a diagnosis of VaP not PD. CONCLUSIONS: This case of pathologically confirmed VaP misdiagnosed as idiopathic PD suggested that we must be vigilant about the possibility of VaP for patients with parkinsonisms, cognitive impairments, early behavioral and psychological symptoms,imaging performances of cerebral small vessel disease and other vascular damages.