Updated Parkinson's disease motor subtypes classification and correlation to cerebrospinal homovanillic acid and 5-hydroxyindoleacetic acid levels.

Introduction: Motor classifications of Parkinson's Disease (PD) have been widely used. This paper aims to update a subtype classification using the MDS-UPDRS-III and determine if cerebrospinal neurotransmitter profiles (HVA and 5-HIAA) differ between these subtypes in a cohort from the Parkinson's Progression Marker Initiative (PPMI). Methods: UPDRS and MDS-UPDRS scores were collected for 20 PD patients. Akinetic-rigid (AR), Tremor-dominant (TD), and Mixed (MX) subtypes were calculated using a formula derived from UPDRS, and a new ratio was developed for subtyping patients with the MDS-UPDRS. This new formula was subsequently applied to 95 PD patients from the PPMI dataset, and subtyping was correlated to neurotransmitter levels. Data were analyzed using receiver operating characteristic models and ANOVA. Results: Compared to previous UPDRS classifications, the new MDS-UPDRS TD/AR ratios produced significant areas under the curve (AUC) for each subtype. The optimal sensitivity and specificity cutoff scores were ≥0.82 for TD, ≤0.71 for AR, and >0.71 and <0.82 for Mixed. Analysis of variance showed that the AR group had significantly lower HVA and 5-HIAA levels than the TD and HC groups. A logistic model using neurotransmitter levels and MDS-UPDRS-III could predict the subtype classification. Conclusions: This MDS-UPDRS motor classification system provides a method to transition from the original UPDRS to the new MDS-UPDRS. It is a reliable and quantifiable subtyping tool for monitoring disease progression. The TD subtype is associated with lower motor scores and higher HVA levels, while the AR subtype is associated with higher motor scores and lower 5-HIAA levels.

Olfactory Dysfunction in Huntington's Disease.

Olfactory dysfunction is a common symptom in patients with neurodegenerative disorders, including Huntington's disease (HD). Understanding its pathophysiology is important in establishing a preventive and therapeutic plan. In this literature review, we cover the physiology of olfaction, its role in neurodegeneration, and its characteristics in patients with HD. In the general population, olfactory dysfunction is present in 3.8-5.8%and the prevalence increases significantly in those older than 80 years. For HD, data regarding prevalence rates are lacking and the scales used have been inconsistent or have been restructured due to concerns about cross-cultural understanding. Pathogenic huntingtin deposits have been found in the olfactory bulb of individuals with HD, although no studies have correlated this with the grade of olfactory impairment. Olfactory dysfunction is present in both premanifest and manifest patients with HD, showing a progressive decline over time with more severe deficits at advanced stages. No specific treatment for olfactory impairment in HD has been proposed; identifying and avoiding potential medications that cause olfactory dysfunction, as well as general safety recommendations remain the basis of the therapeutic strategy.

Daniel Alcides Carrion (1857-1885) and a history of medical martyrdom.

Daniel Carrion, a sixth-year medical student, died while investigating the effects of self-inoculation of the causative organism of Oroya Fever and Bartonellosis and thereby contributed to understanding of the disease before the organisms had been identified.

Lionel Charles Renwick (Rennick) Emmett (1913-96): physician and Olympian.

Lionel Charles Renwick Emmett, a physician who trained in pre-independent India as a medical student, participated in the 1936 Berlin Summer Olympics as a part of the Indian field hockey team that won the Gold Medal.