Heloisa Helena Ruocco

Longitudinal analysis of regional grey matter loss in Huntington disease: effects of the length of the expanded CAG repeat

Background: The mechanisms guiding the progression of neuronal damage in patients with Huntington disease (HD) are not completely understood. It is unclear whether the genotype—that is, the length of the expanded CAG repeat—guides the location and speed of grey matter decline once HD is clinically manifested. Moreover, the relationship between cortical and subcortical grey matter atrophy and the severity of motor symptoms of HD is controversial. Objectives: In this article, we longitudinally studied, over the period of 1 year, a cohort of 49 patients with HD. We investigated: first, the clinical relevance of regional progressive grey matter atrophy; and second, the relationship between the ratio of atrophy progression and genotype. Methods: The length of the expanded CAG repeat was quantified for all patients and the United Huntington’s Disease Rating Scale (UHDRS) was used to rate the severity of clinical symptoms. Grey matter atrophy was determined using voxel-based morphometry (VBM) of brain MRI. Progression of atrophy was quantified in 37 patients who were submitted to two different MRI scans, the second scan 1 year later than the first. Results: Overall, patients exhibited progressive atrophy involving the caudate, pallidum, putamen, insula, cingulate cortex, cerebellum, orbitofrontal cortex, medial temporal lobes and middle frontal gyri. Patients with a larger UHDRS score exhibited selective atrophy of the caudate, thalamus, midbrain, insula and frontal lobes. Patients with longer, expanded CAG repeat sequences showed faster rates and more widespread atrophy, particularly those patients with more than 55 expanded CAG repeats. Conclusions: These results confirm that brain atrophy progresses after the clinical onset of HD and that regional atrophy is related to symptom severity. Moreover, our results also indicate that intensity and rate of progression of brain atrophy are more pronounced in patients with larger, expanded CAG repeat sequences.

Striatal and extrastriatal atrophy in Huntington's disease and its relationship with length of the CAG repeat

Huntingtons disease (HD) is an autosomal dominant neurodegenerative disorder that affects the striatum most severely. However, except for juvenile forms, relative preservation of the cerebellum has been reported. The objective of the present study was to perform MRI measurements of caudate, putamen, cerebral, and cerebellar volumes and correlate these findings with the length of the CAG repeat and clinical parameters. We evaluated 50 consecutive patients with HD using MRI volumetric measurements and compared them to normal controls. Age at onset of the disease ranged from 4 to 73 years (mean: 43.1 years). The length of the CAG repeat ranged from 40 to 69 (mean: 47.2 CAG). HD patients presented marked atrophy of the caudate and putamen, as well as reduced cerebellar and cerebral volumes. There was a significant correlation between age at onset of HD and length of the CAG repeat, as well as clinical disability and age at onset. The degree of basal ganglia atrophy correlated with the length of the CAG repeat. There was no correlation between cerebellar or cerebral volume and length of the CAG repeat. However, there was a tendency to a positive correlation between duration of disease and cerebellar atrophy. While there was a negative correlation of length of the CAG repeat with age at disease onset and with striatal degeneration, its influence on extrastriatal atrophy, including the cerebellum, was not clear. Extrastriatal atrophy occurs later in HD and may be related to disease duration.

Clinical presentation of juvenile Huntington disease

OBJECTIVE To describe the clinical presentation a group of patients with juvenile onset of Huntington disease. METHOD All patients were interviewed following a structured clinical questionnaire. Patients were genotyped for the trinucleotide cytosine-adenine-guanine (CAG) repeat in the Huntington Disease gene. High resolution brain MRI was performed in all patients. RESULTS We identified 4 patients with juvenile onset of disease among 50 patients with Huntington disease followed prospectively in our Neurogenetics clinic. Age at onset varied from 3 to 13 years, there were 2 boys, and 3 patients had a paternal inheritance of the disease. Expanded Huntington disease allele sizes varied from 41 to 69 trinucleotide repeats. The early onset patients presented with rigidity, bradykinesia, dystonia, dysarthria, seizures and ataxia. MRI showed severe volume loss of caudate and putamen nuclei (p=0.001) and reduced cerebral and cerebellum volumes (p=0.01). CONCLUSION 8% of Huntington disease patients seen in our clinic had juvenile onset of the disease. They did not present with typical chorea as seen in adult onset Huntington disease. There was a predominance of rigidity and bradykinesia. Two other important clinical features were seizures and ataxia, which related with the imaging findings of early cortical atrophy and cerebellum volume loss.

Interferon-beta modifies the peripheral blood cell cytokine secretion in patients with multiple sclerosis

Immunotherapy with Interferon-beta (IFNbeta) results in remarkably beneficial effects in patients with relapsing-remitting multiple sclerosis (MS), although the mechanisms by which it exerts these beneficial effects remain poorly understood. An investigation was made of the effects of IFNbeta on pro-inflammatory and anti-inflammatory cytokine production in peripheral blood cells in MS patients, both untreated and those undergoing immunotherapy, as well as in healthy controls. Results show a significant increase in the production of pro-inflammatory cytokines such as TNFalpha, IFNgamma and IL-12 in the plasma and in the supernatant of leukocyte cultures from MS patients with the untreated disease; IFNbeta administration significantly reduced the levels of TNFalpha and IFNgamma, with no changes in the level of IL-12. The Interferon-beta therapy also led to a significant increase in the production of IL-10, as well as a slight increase in that of TGFbeta. The reduction in pro-inflammatory cytokine production in the treated MS patient group, accompanied by a simultaneous increase in the production of anti-inflammatory cytokines and the reduction of relapse rates suggests that the beneficial effects of IFNbeta immunotherapy result, at least in part, from the modulation of cytokine patterns.

Cytokines and intrathecal IgG synthesis in multiple sclerosis patients during clinical remission

Cytokines and intrathecal IgG synthesis were determined in the cerebrospinal fluid (CSF) and sera to evaluate inflammatory activity in multiple sclerosis (MS) patients during clinical remission. Although the disease was stable, there had been a significant increase of proinflammatory cytokines such as TNFalpha and IFNgamma in the CSF and serum, with no significant changes of IL12 and IL10 production. The changes in the cytokine production patterns were associated with an increase of leukocytes in the CSF, as well as the presence of oligoclonal bands suggesting intrathecal IgG synthesis. These results suggest that even when the disease is clinically silent, one can observe inflammatory activity in these MS patients.

Evidence of Thalamic Dysfunction in Huntington Disease by Proton Magnetic Resonance Spectroscopy

Our objective was to investigate thalamic neuronal dysfunction in patients with Huntington disease (HD). We performed localized single‐voxel proton magnetic resonance spectroscopy (MRS) of the thalamus in 22 HD patients and 25 healthy individuals. The mean age of patients was 48.5 years (ranging from 32 to 71 years). Age at onset varied between 20 and 66 years (mean 38.9 years). The expanded CAG repeat ranged from 40 to 52 (mean 45.2) CAGs. The mean age of control group was 35.4 years, ranging from 19 to 67 years. N‐acetylaspartate (NAA) relative to creatine (NAA/Cr) values in the thalamus of HD patients were decreased when compared with controls (P = 0.0001). The spectroscopic findings were not correlated with motor impairment. However, there was a positive correlation between duration of disease and motor impairment (P = 0.02, r = 0.48), and a tendency for positive correlation between duration of disease and NAA/Cr (P = 0.059, r = 0.4). We found decreased NAA/Cr values in the thalamus of patients with HD, indicating neuronal loss or dysfunction. This is in agreement with previous studies that indicated the involvement of mitochondrial dysfunction in the neurodegenerative process of HD.

Natalizumab adverse events are rare in patients with multiple sclerosis

OBJECTIVE To assess the prevalence and the profile of adverse events (AE) of natalizumab in patients with multiple sclerosis (MS). METHODS Data collection from neurologists attending to patients with MS at specialized units in Brazil. RESULTS Data from 103 patients attending the infusion centers of 16 MS units in 9 Brazilian states were included in the study. The total number of infusions was 1,042. Seventy-nine patients (76.7%) did not present any AE. Twenty-four patients (23.3%) presented only mild AE. There were three major AE, including two deaths. These three occurrences, although not necessarily being drug-related, must be taken into consideration. CONCLUSION The profile of AEs for natalizumab shows that 97% of patients have none or only mild AE. However, still due to safety worries, the use of this medication should be restricted to MS units under the care of specialized neurologists.

Intrathecal immunoglobulin G synthesis and brain injury by quantitative MRI in multiple sclerosis

Objectives: It was the aim of this study to evaluate if the quantitative intrathecal immunoglobulin G (IgG) synthesis correlates with the brain atrophy and the total lesion volume (TLV) in brain magnetic resonance imaging (MRI) of multiple sclerosis (MS) patients. Methods: A total of 50 patients with relapsing-remitting MS were included in this study. MRIs were performed and cerebrospinal fluid samples were collected during the diagnostic determination when patients were in remission without treatment. Results: At study baseline, IgG index values were elevated in 36 patients (72%), and oligoclonal IgG bands were positive in 42 of 50 patients (84%). Brain MRI was abnormal in 94% of patients, and, compared with healthy controls, brain atrophy was observed in MS patients. A positive correlation among IgG index, cerebrospinal fluid leukocyte count and TLV was observed; the Expanded Disability Status Scale correlated positively with TLV and the number of lesions, although a significant relationship between disability and brain atrophy was not demonstrated. Conclusions: Although new parameters will be necessary in longitudinal studies to characterize the axonal injury in various stages of the disease, the data suggest that the high intrathecal IgG synthesis may predict a greater brain lesion burden.

Nearly one-half of Brazilian patients with multiple sclerosis using natalizumab are DNA-JC virus positive

OBJECTIVE Natalizumab is a new and efficient treatment for multiple sclerosis (MS). The risk of developing progressive multifocal leukoencephalopathy (PML) during the use of this drug has created the need for better comprehension of JC virus (JCV) infection. The objective of the present study was to assess the prevalence of JCV-DNA in Brazilian patients using natalizumab. METHOD Qualitative detection of the JCV in the serum was performed with real-time polymerase chain reaction (PCR). RESULTS In a group of 168 patients with MS who were undergoing treatment with natalizumab, JCV-DNA was detectable in 86 (51.2%) patients. DISCUSSION Data on JCV-DNA in Brazil add to the worldwide assessment of the prevalence of the JCV in MS patients requiring treatment with natalizumab.

Alternatives for reducing relapse rate when switching from natalizumab to fingolimod in multiple sclerosis

ABSTRACT Natalizumab is a therapeutic option for treating multiple sclerosis (MS) and is particularly efficacious for patients with highly active disease. A long washout period has been recommended between withdrawal of natalizumab and start of fingolimod (another option for treating MS). This long washout period has been associated with a significant increase in MS activity. In the present study, a group of 96 patients who were switched from natalizumab to fingolimod had short washout periods between drugs, or monthly corticosteroid pulse therapy if longer washout periods were recommended. This therapeutic approach led to the lowest reported relapse rate so far, among patients with MS switching from natalizumab to fingolimod (8.3%). No complications from short withdrawal were observed in this group of patients.