Raphael Machado de Castilhos

A Randomized, Phase 2 Clinical Trial of Lithium Carbonate in Machado-Joseph Disease

Because lithium exerts neuroprotective effects in preclinical models of polyglutamine disorders, our objective was to assess the safety and efficacy of lithium carbonate (0.5‐0.8 milliequivalents per liter) in patients with Machado‐Joseph disease (spinocerebellar ataxia type 3 [MJD/SCA3]).

Mutations, Clinical Findings and Survival Estimates in South American Patients with X-Linked Adrenoleukodystrophy

In this study, we analyzed the ABCD1 gene in X-linked adrenoleukodystrophy (X-ALD) patients and relatives from 38 unrelated families from South America, as well as phenotypic proportions, survival estimates, and the potential effect of geographical origin in clinical characteristics. Methods X- ALD patients from Brazil, Argentina and Uruguay were invited to participate in molecular studies to determine their genetic status, characterize the mutations and improve the genetic counseling of their families. All samples were screened by SSCP analysis of PCR fragments, followed by automated DNA sequencing to establish the specific mutation in each family. Age at onset and at death, male phenotypes, genetic status of women, and the effect of family and of latitude of origin were also studied. Results We identified thirty-six different mutations (twelve novel). This population had an important allelic heterogeneity, as only p.Arg518Gln was repeatedly found (three families). Four cases carried de novo mutations. Intra-familiar phenotype variability was observed in all families. Out of 87 affected males identified, 65% had the cerebral phenotype (CALD). The mean (95% CI) ages at onset and at death of the CALD were 10.9 (9.1–12.7) and 24.7 (19.8–29.6) years. No association was found between phenotypic manifestations and latitude of origin. One index-case was a girl with CALD who carried an ABCD1 mutation, and had completely skewed X inactivation. Conclusions This study extends the spectrum of mutations in X-ALD, confirms the high rates of de novo mutations and the absence of common mutations, and suggests a possible high frequency of cerebral forms in our population.

Huntington disease and Huntington disease-like in a case series from Brazil

The aim of this study was to identify the relative frequency of Huntingtons disease (HD) and HD‐like (HDL) disorders HDL1, HDL2, spinocerebellar ataxia type 2 (SCA2), SCA17, dentatorubral‐pallidoluysian degeneration (DRPLA), benign hereditary chorea, neuroferritinopathy and chorea‐acanthocytosis (CHAC), in a series of Brazilian families. Patients were recruited in seven centers if they or their relatives presented at least chorea, besides other findings. Molecular studies of HTT, ATXN2, TBP, ATN1, JPH3, FTL, NKX2‐1/TITF1 and VPS13A genes were performed. A total of 104 families were ascertained from 2001 to 2012: 71 families from South, 25 from Southeast and 8 from Northeast Brazil. There were 93 HD, 4 HDL2 and 1 SCA2 families. Eleven of 104 index cases did not have a family history: 10 with HD. Clinical characteristics were similar between HD and non‐HD cases. In HD, the median expanded (CAG)n (range) was 44 (40–81) units; R2 between expanded HTT and age‐at‐onset (AO) was 0.55 (p = 0.0001, Pearson). HDL2 was found in Rio de Janeiro (2 of 9 families) and Rio Grande do Sul states (2 of 68 families). We detected HD in 89.4%, HDL2 in 3.8% and SCA2 in 1% of 104 Brazilian families. There were no cases of HDL1, SCA17, DRPLA, neuroferritinopathy, benign hereditary chorea or CHAC. Only six families (5.8%) remained without diagnosis.

Planning future clinical trials in Machado Joseph disease: Lessons from a phase 2 trial

BACKGROUND In a recent phase 2 clinical trial in spinocerebellar ataxia type 3/Machado Joseph disease (SCA3/MJD), a neurogenetic disorder without specific therapy, benefits of lithium carbonate were found only on secondary efficacy outcomes, all related to ataxic features. In order to help designing future studies, we further analyzed the trial data searching for treatment response modifiers and metric properties of spinocerebellar ataxia (SCA) scales. METHODS Efficacy analysis was performed with the Neurological Examination Score for the Assessment of Spinocerebellar Ataxia (NESSCA) and the Scale for the Assessment and Rating of Ataxia (SARA) subscores and with the subgroup of patients with independent gait according to the 8-meter walking-time (8MW). Interactions of clinical/molecular findings with treatment response, minimally important differences (MIDs), and sample size estimations for NESSCA, SARA, Spinocerebellar Ataxia Functional Index (SCAFI) and Composite Cerebellar Functional Score (CCFS) were evaluated. RESULTS 62 SCA3/MJD patients had been randomly assigned (1:1) for the double-blind, placebo-controlled trial. While cerebellar NESSCA (range: 0-7 points) differed between groups 0.64 points (95% CI 0.23 to 1.05, p<0.001) over the whole 48weeks of study, favoring lithium, no effect was found on non-ataxia subscores. Among patients able to perform the 8MW on baseline, NESSCA (p=0.010) and SCAFI (p=0.015) differed between groups favoring lithium. Finally, estimated sample sizes for the scales were provided. CONCLUSION Lithium efficacy on cerebellar NESSCA, and on SCAFI and CCFS in the primary analysis, together with the lack of effect on non-ataxia features suggests that lithium should be tested in phase 3 trials in SCA3/MJD and that ataxia scales should be preferred to multisystem neurological instruments as the primary outcome. The inclusion of early stage patients is advisable in future clinical trials in SCA3/MJD. TRIAL REGISTRATION clinicaltrials.gov identifier: NCT01096082.

Genetic aspects of Huntington's disease in Latin America. A systematic review.

We aimed to present a systematic review on Huntingtons disease (HD) in Latin America (LA). PubMed and LILACS were searched up to March 2015, reporting confirmed HD cases in LA. Case series, cross‐sectional, case–control, and prospective studies were included. From 534 communications, 47 were eligible. Population‐based studies were not found; minimal prevalence of 0.5–4/100,000 was estimated for Venezuela and Mexico. Geographical isolates were well characterized in Venezuela and in Peru. CAG repeats at HTT gene varied between 7–33 and 37–112 in normal and expanded alleles, respectively. Intermediate alleles were found in 4–10% of controls. Ages at onset and the expanded CAG repeats correlated with r from – 0.55 to –0.91. While haplotype patterns of Venezuelan and Brazilian chromosomes were similar to those observed in Europeans, haplotypes from Peruvian HD patients did not match the same pattern. The limited number of papers found suggests that HD is poorly diagnosed in LA. Minimal prevalence seemed to be halfway between those of Caucasians and Asians. Range of CAG repeats was similar to those of Europeans. Haplotype studies indicate that majority of HD patients might be of Caucasian descent; an Asian origin for some Peruvian patients was proposed.

Peripheral Oxidative Stress Biomarkers in Spinocerebellar Ataxia Type 3/Machado–Joseph Disease

Objectives Spinocerebellar ataxia type 3/Machado–Joseph disease (SCA3/MJD) is a polyglutamine disorder with no current disease-modifying treatment. Conformational changes in mutant ataxin-3 trigger different pathogenic cascades, including reactive oxygen species (ROS) generation; however, the clinical relevance of oxidative stress elements as peripheral biomarkers of SCA3/MJD remains unknown. We aimed to evaluate ROS production and antioxidant defense capacity in symptomatic and presymptomatic SCA3/MJD individuals and correlate these markers with clinical and molecular data with the goal of assessing their properties as disease biomarkers. Methods Molecularly confirmed SCA3/MJD carriers and controls were included in an exploratory case–control study. Serum ROS, measured by 2′,7′-dichlorofluorescein diacetate (DCFH-DA) as well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) antioxidant enzyme activities, levels were assessed. Results Fifty-eight early/moderate stage symptomatic SCA3/MJD, 12 presymptomatic SCA3/MJD, and 47 control individuals were assessed. The DCFH-DA levels in the symptomatic group were 152.82 nmol/mg of protein [95% confidence interval (CI), 82.57–223.08, p < 0.001] higher than in the control and 243.80 nmol/mg of protein (95% CI, 130.64–356.96, p < 0.001) higher than in the presymptomatic group. The SOD activity in the symptomatic group was 3 U/mg of protein (95% CI, 0.015–6.00, p = 0.048) lower than in the presymptomatic group. The GSH-Px activity in the symptomatic group was 13.96 U/mg of protein (95% CI, 5.90–22.03, p < 0.001) lower than in the control group and 20.52 U/mg of protein (95% CI, 6.79–34.24, p < 0.001) lower than in the presymptomatic group and was inversely correlated with the neurological examination score for spinocerebellar ataxias (R = −0.309, p = 0.049). Conclusion Early/moderate stage SCA3/MJD patients presented a decreased antioxidant capacity and increased ROS generation. GSH-Px activity was the most promising oxidative stress disease biomarker in SCA3/MJD. Further longitudinal studies are necessary to identify both the roles of redox parameters in SCA3/MJD pathophysiology and as surrogate outcomes for clinical trials.

ATXN3, ATXN7, CACNA1A, and RAI1 Genes and Mitochondrial Polymorphism A10398G Did Not Modify Age at Onset in Spinocerebellar Ataxia Type 2 Patients from South America

Fernanda S. Pereira & Thais L. Monte & Lucas D. Locks-Coelho & Amanda S. P. Silva & Orlando Barsottini & Jose L. Pedroso & Mario Cornejo-Olivas & Pilar Mazzetti & Clecio Godeiro & Fernando R. Vargas & Maria-Angelica F. D. Lima & Helio van der Linden Jr & Maria Betânia Pereira Toralles & Paula F. V. Medeiros & Erlane Ribeiro & Pedro Braga-Neto & Diego Salarini & Raphael M. Castilhos & Maria-Luiza Saraiva-Pereira & Laura Bannach Jardim & Rede Neurogenetica

Free and Cued Selective Reminding Test sensitivity

We read with great interest the recent article by Teichmann et al. [1], who presented results of the Free and Cued Selective Reminding Test (FCSRT) accuracy to differentiate typical (amnestic) Alzheimer’s disease (AD) from other neurodegenerative diseases. The authors assessed FCSRT in a group of 992 individuals, most of them with the diagnosis of AD, and stated that FCSRT would have a sensitivity of 100% and a specificity of 75% to diagnose typical AD. A diagnostic test for amnestic variant of AD that is very sensitive and specific in early stages of dementia would be extremely useful to distinguish it more accurately from other neurodegenerative diseases, especially in the context of possible disease-modifying therapy, probably effective in early or prodromic phases. FCSRT has been suggested by the International Working Group as a test to characterize amnestic syndrome of hippocampal type [2] and in fact has been demonstrating high correlation with AD pathology [3] and high sensitivity to predict mild cognitive impairment conversion to dementia [4]. However, we consider that the methods used to analyze the test performance introduced some bias to the results. The authors stated, in the methods section, that FCSRT was used to select patients to enter the study, rather than other test or set of tests, that would diagnose a patient as having amnestic variant of AD; that is, all patients with amnestic hippocampal syndrome were selected by the same instrument that is in fact being tested. Indeed, the sensitivity described in table 1 was 100%, both for AD dementia as for prodromal AD. The use of biomarkers for AD does not help in the mitigation of this bias, as this simply implies that patients included in the study had most likely AD pathology. Both the sensitivity and specificity of a test must be established regardless of the means for which the true diagnosis was established. In other words, the diagnostic test being evaluated should not be a part of the information used to establish the diagnosis [5]. Because there is no gold standard test for the presence of hippocampal amnestic deficits, it would be more useful to compare FCSRT with a larger

The Use of the Clinical Dementia Rating Scale Sum of Boxes Scores in Detecting and Staging Cognitive Impairment/Dementia in Brazilian Patients With Low Educational Attainment

The aim of this study was to evaluate the Clinical Dementia Rating Scale sum of the boxes (CDR-SB) diagnostic validity in detecting and staging cognitive impairment/dementia in a sample of Brazilian patients with amnestic mild cognitive impairment (aMCI), Alzheimer disease (AD), and vascular dementia (VD), of low educational attainment. Data were obtained from the Dementia Clinic of Hospital de Clínicas de Porto Alegre database and included 407 participants (115 healthy elderly, 41 aMCI, 165 AD, and 86 VD). Receiver operating characteristic curves were generated to detect best CDR-SB cutoffs. Average education was 4 years. A CDR-SB cutoff ≥0.5 was obtained to correctly identify MCI from normal controls (sensitivity of 100% and specificity of 98.3%). The cutoff ≥4.5 correctly identified aMCI from dementia altogether or separately (AD and VD) (sensitivity of 96.4% and specificity of 100%) in 96.9% of the individuals. Similar AUC was found for ⩽4 and >4 years of education. The CDR-SB showed good clinical validity to detect and classify severity of cognitive impairment Brazilian patients with low educational attainment. Findings were similar to the original study carried out with higher educated individuals.