Toward a New Biomarker of Parkinson’s Disease by Study of Alpha Synuclein on Upper Enteric System by Endoscopy (I1.014)

Introduction:Parkinson’s disease (PD) is a neurodegenerative disorder diagnosed with the clinical hallmarks of motor parkinsonism . Non-motor signs (NMS) including autonomic dysfunction, sleep disturbances, psychiatric and cognitive disturbances may precede the first signs of motor parkinsonism. Dopaminergic neuronal loss involved occurs early and is not just nigrostriatal. It would affect other structures such as enteric nervous system (ENS). Alpha synuclein deposition follows neurodegeneration. The objective of our study was to investigate the relationship between alpha synuclein deposition at the SNE and PD and clinical-histological correlations arising. Methods: We conducted a retrospective study in Neurology Department of Charles Nicolle hospital of Tunis during 2 years (2013-2014) including PD patients. Clinical data were collected and analyzed. Digestive endoscopy with biopsies of upper digestive tract (UDT) and immunohistochemistry study were performed. Results: 13 patients were included (16♂/14♀). Average age was 65 years. Inaugural symptoms were: motor (8 patients), non-motor (20 patients) and both (2 patients). Inaugural NMS were hyposmia, gastrointestinal disturbances and mood disorders. Endoscopy showed motor dysfunction of the UDT in 5 patients. Immunohistochemistry confirmed the diagnosis of PD in 100[percnt] patients through the presence of alpha synuclein deposits in ENS. Lesion load in alpha synuclein was significantly correlated with the severity of NMS especially gastrointestinal and the severity of motor disability. A rostrocaudal gradient of the progression of ENS lesions was found.Conclusions: Involvement of the ENS in PD began several decades before the onset of motor signs. Gastrointestinal disturbances are frequent during PD and are explained by ENS’s lesions which would be involved in the pathophysiology of the disease. Severity of the synucleinopathy in ENS is correlated with the severity of PD. Gastrointestinal tract might be a portal of pathogen entry in PD. We have shown that the UDT biopsies of ENS can be used as a valid biomarker of PD. Disclosure: Dr. Ben Ali has nothing to disclose. Dr. Afef has nothing to disclose. Dr. Saloua has nothing to disclose. Dr. Meriem has nothing to disclose. Dr. Saloua has nothing to disclose. Dr. Radhouane has nothing to disclose. Dr. Taoufik has nothing to disclose. Dr. Hawat has nothing to disclose. Dr. Samir has nothing to disclose.