Kuru, the first human prion disease was transmitted to chimpanzees by D. Carleton Gajdusek (1923–2008). In this review, we summarize the history of this seminal discovery, its anthropological background, epidemiology, clinical picture, neuropathology, and molecular genetics. We provide descriptions of electron microscopy and confocal microscopy of kuru amyloid plaques retrieved from a paraffin-embedded block of an old kuru case, named Kupenota. The discovery of kuru opened new vistas of human medicine and was pivotal in the subsequent transmission of Creutzfeldt–Jakob disease, as well as the relevance that bovine spongiform encephalopathy had for transmission to humans. The transmission of kuru was one of the greatest contributions to biomedical sciences of the 20th century.

Introduction. The aim of our study was to find out the opinion of patients with Parkinson’s Disease (PD) whose disease was preceded by REM sleep behaviour disorder (RBD) regarding early information about the high risk of phenoconversion in RBD. Clinical rationale for the study. RBD is an early clinical manifestation of α-synucleinopathies with a more than 90% risk of phenoconversion to PD, dementia with Lewy bodies (DLB) or multiple system atrophy (MSA). It remains a subject for debate as to whether and how RBD patients should be informed about the high risk of phenoconversion. The patient’s right to full knowledge regarding his or her health conflicts with the potentially destructive impact of this information on his or her mental state and quality of life of them and their relatives. Material and methods. Thirty-nine patients with PD whose disease was preceded by RBD were surveyed. Data on the course of RBD and PD was collected. Questions were asked about early information about the high risk of phenoconversion to patients with RBD and factors determining the opinion of the surveyed persons. Results. The majority ( > 60%) of respondents gave a positive answer when asked whether patients should be informed about their high risk of developing PD once diagnosed with RBD. Only a few (7.7%) respondents believed that disclosing such information to the patient should be possible only after obtaining his or her consent. Respondents associated consent to information about the high risk of developing PD in people with RBD with high expectations of the healthcare system. We were unable to determine whether factors such as the gender of the subject, the clinical course of the PD, and the RBD duration had an impact on patients’ opinions regarding disclosing knowledge about phenoconversion. Conclusions and clinical implications. Our study provides important information that should influence physicians’ communication with patients with RBD, especially regarding how they communicate about the high risk of phenoconversion. Introduction. The aim of our study was to find out the opinion of patients with Parkinson’s Disease (PD) whose disease was preceded by REM sleep behaviour disorder (RBD) regarding early information about the high risk of phenoconversion in RBD. Clinical rationale for the study. RBD is an early clinical manifestation of α-synucleinopathies with a more than 90% risk of phenoconversion to PD, dementia with Lewy bodies (DLB) or multiple system atrophy (MSA). It remains a subject for debate as to whether and how RBD patients should be informed about the high risk of phenoconversion. The patient’s right to full knowledge regarding his or her health conflicts with the potentially destructive impact of this information on his or her mental state and quality of life of them and their relatives. Material and methods. Thirty-nine patients with PD whose disease was preceded by RBD were surveyed. Data on the course of RBD and PD was collected. Questions were asked about early information about the high risk of phenoconversion to patients with RBD and factors determining the opinion of the surveyed persons. Results. The majority ( > 60%) of respondents gave a positive answer when asked whether patients should be informed about their high risk of developing PD once diagnosed with RBD. Only a few (7.7%) respondents believed that disclosing such information to the patient should be possible only after obtaining his or her consent. Respondents associated consent to information about the high risk of developing PD in people with RBD with high expectations of the healthcare system. We were unable to determine whether factors such as the gender of the subject, the clinical course of the PD, and the RBD duration had an impact on patients’ opinions regarding disclosing knowledge about phenoconversion. Conclusions and clinical implications. Our study provides important information that should influence physicians’ communication with patients with RBD, especially regarding how they communicate about the high risk of phenoconversion.

The formulation of the gut–brain–microbiota axis (GBA) theory has led to new research directions that have expanded our understanding of the pathogenesis, phenotypic variability, and clinical course of Parkinson’s disease (PD). Models of PD pathogenesis, based on the Braak hypothesis, suggest a subtype of the disease in which pathological changes begin in the gut many years before the onset of brain pathology and the manifestation of motor symptoms. Gut microbiota may influence nervous system function along the GBA by influencing intestinal permeability, chronic inflammation, and α-synuclein aggregation. Accumulating evidence suggests that the gut microbiota may also regulate the synthesis and metabolism of neurotransmitters, including dopamine (DA), serotonin (5-HT), acetylcholine (ACh) and γ-aminobutyric acid (GABA), both in the gut and brain, and indirectly stimulate central nervous system activity via the vagus nerve, which receives signals from the enteric nervous system. Research on the effects of microbiota on GBA has paved the way for the identification of novel treatment strategies, including probiotics, prebiotics, synbiotics, postbiotics, antibiotics, and fecal microbiota transplantation (FMT), aimed at not only symptomatic but also disease-modifying treatment of PD. In this article, we propose a novel approach to GBA as a link between gut microbiota and gut and brain neurotransmitter metabolism in PD. We review the latest research on the gut epithelial barrier. We analyze and summarize the potential of therapeutic interventions targeting gut microbiota and their impact on neurotransmitter regulation in PD.

POEMS syndrome is a rare multisystem disorder, characterized by the presence of polyneuropathy, organomegaly, endocrinopathy, monoclonal protein and skin changes. The variety of clinical pictures and asynchronous manifestation of dominant features make diagnosis difficult. We report a case of a 42-year-old man with polyneuropathy who was initially negative for monoclonal protein and so Guillain-Barré syndrome was diagnosed. Other signs and symptoms, including monoclonal gammopathy, developed later in the course of the disease and finally POEMS syndrome was diagnosed.

Aim. Drug-induced parkinsonism (DIP) is the most common form of parkinsonism after Parkinson’s disease (PD) itself. It has been widely believed that DIP is characterised by symmetry of symptoms. Studies of patients with DIP in whom PD had been ruled out by SPECT-DaTSCAN have shown that symptom asymmetry is a common element of DIP clinical presentation. The aim of our study was to determine whether the asymmetry of symptoms in DIP is related to any abnormality within the presynaptic part of the nigrostriatal dopaminergic system. Materials and methods. Eleven patients with the diagnosis of DIP and asymmetric symptoms were studied. Their individual SPECT-DaTSCANs were normal. Indices calculated for the whole group of radiotracer uptake in the whole striatum, putamen and caudate contralateral to more severe DIP symptoms were compared to values obtained in the opposite hemisphere. Results. We did not find significant differences in radiotracer uptake in structures contralateral to more severe clinical symptoms when compared to the homolateral hemisphere. Conclusions. Our results have not confirmed the presence of a presynaptic nigrostriatal deficit which could be related to asymmetry of DIP. The factors responsible for the asymmetry of DIP symptoms should be sought in the postsynaptic part of the nigrostriatal dopaminergic system. Aim. Drug-induced parkinsonism (DIP) is the most common form of parkinsonism after Parkinson’s disease (PD) itself. It has been widely believed that DIP is characterised by symmetry of symptoms. Studies of patients with DIP in whom PD had been ruled out by SPECT-DaTSCAN have shown that symptom asymmetry is a common element of DIP clinical presentation. The aim of our study was to determine whether the asymmetry of symptoms in DIP is related to any abnormality within the presynaptic part of the nigrostriatal dopaminergic system. Materials and methods. Eleven patients with the diagnosis of DIP and asymmetric symptoms were studied. Their individual SPECT-DaTSCANs were normal. Indices calculated for the whole group of radiotracer uptake in the whole striatum, putamen and caudate contralateral to more severe DIP symptoms were compared to values obtained in the opposite hemisphere. Results. We did not find significant differences in radiotracer uptake in structures contralateral to more severe clinical symptoms when compared to the homolateral hemisphere. Conclusions. Our results have not confirmed the presence of a presynaptic nigrostriatal deficit which could be related to asymmetry of DIP. The factors responsible for the asymmetry of DIP symptoms should be sought in the postsynaptic part of the nigrostriatal dopaminergic system.