William Fernández

Exploration of genetic susceptibility factors for Parkinson’s disease in a South American sample

1Neurosciences Research Group, School of Medicine and Institute of Genetics, Universidad Nacional de Colombia, Bogota, Colombia 2Department of Internal Medicine, 3Department of Pediatrics, 4Department of Pathology, School of Medicine, Universidad Nacional de Colombia, Bogota, Colombia 5MSc Program in Neurosciences, Universidad Nacional de Colombia, Bogota, Colombia 6Present address: Biomedical Science Research Group, School of Medicine, Universidad Antonio Narino, Bogota, Colombia

Analysis of four scales for global severity evaluation in Parkinson’s disease

Global evaluations of Parkinson’s disease (PD) severity are available, but their concordance and accuracy have not been previously tested. The present international, cross-sectional study was aimed at determining the agreement level among four global scales for PD (Hoehn and Yahr, HY; Clinical Global Impression of Severity, CGIS; Clinical Impression of Severity Index, CISI-PD; and Patient Global Impression of Severity, PGIS) and identifying which of them better correlates with itemized PD assessments. Assessments included additional scales for evaluation of the movement impairment, disability, affective disorders, and quality of life. Spearman correlation coefficients, weighted and generalized kappa, and Kendall’s concordance coefficient were used. Four hundred thirty three PD patients, 66% in HY stages 2 or 3, mean disease duration 8.8 years, were analyzed. Correlation between the global scales ranged from 0.60 (HY with PGIS) to 0.91 (CGIS with CISI-PD). Kendall’s coefficient of concordance resulted 0.76 (P<0.0001). HY and CISI-PD showed the highest association with age, disease duration, and levodopa-equivalent daily dose, and CISI-PD with measures of PD manifestations, disability, and quality of life. PGIS and CISI-PD correlated similarly with anxiety and depression scores. The lowest agreement in classifying patients as mild, moderate, or severe was observed between PGIS and HY or CISI-PD (58%) and the highest between CGIS and CISI-PD (84.3%). The four PD global severity scales agree moderately to strongly among them; clinician-based ratings estimate PD severity, as established by other measures, better than PGIS; and the CISI-PD showed the highest association with measures of impairment, disability, and quality of life.

Care of patients with Huntington's disease in South America: a survey

Huntingtons disease (HD) is a rare neurodegenerative disease with a multitude of symptoms, which requires access to specialized multidisciplinary care for adequate management. The aim of this study was to survey the characteristics of care in various HD centers in South America (SA). Methods A questionnaire was sent to 24 centers involved in the care for HD patients in SA. Results Of the total 24 centers, 19 (79.2%) are academic units. The majority of centers (62.5%) are general movement disorders clinics. Multidisciplinary care is available in 19 (79.2%) centers and in 20 (83.3%) care is provided free of charge. Genetic testing and counseling are available in 25 and 66.6% of centers, respectively. The majority of centers (83.3%) have no institutional support for end-stage care. Conclusions Although HD centers in SA are committed to providing multidisciplinary care, access to genetic counseling and end-stage care are lacking in most centers.

Self-Assessment of Disability in Parkinson's Disease: The MDS-UPDRS Part II Versus Clinician-Based Ratings

Parkinsons disease (PD) is characterized by motor and nonmotor symptoms that progress with time, causing disability. The performance of a disease‐specific, self‐applied tool for assessing disability, the MDS‐UPDRS Part II, is tested against generic and rater‐based rating scales.

Análisis de mutaciones en los genes PINK1 Y PARKIN en pacientes colombianos con enfermedad de Parkinson

Parkinsons disease is a complex neurodegenerative disorder, characterized by the progressive loss of dopaminergic neurons of the substance nigra pars compacta. It has been determined that factors both environmental and genetic contribute to its development. Mutations in the genes PINK1 and PARKIN have been associated with the early onset of disease and family history. The goal of this study was to identify mutations in the PINK1 genes (exons 4 and 6) and PARKIN (exons 2 and 7) in 22 Colombian patients with Parkinsons disease of early onset and/ or family history, by PCR amplification and sequencing. The sequences were compared with the reference consensus sequence. A homozygous change mutation was detected in the reading frame (frame shift) c.155dela in exon 2 of the PARKIN gene in a patient with early onset of the disease and family history. In addition, the presence of a polymorphism in intron 2 of the PARKIN gene was identified in seven patients, one of them in homozygous state. Mutations were not found in exons 4 and 6 of the gene PINK1. A homozygous mutation c.155dela in exon 2 of PARKIN was found in a female patient with Parkinsons disease early onset with family history. No changes to the gene PINK1 were found.