Bickerstaff's brainstem encephalitis associated with anti-GM1 and anti-GD1a antibodies.

Bickerstaff's brainstem encephalitis (BBE) is a Guillain-Barré syndrome (GBS) spectrum disorder associated with predominantly central nervous system predilection. Patients exhibit a variable constellation of depressed consciousness, bilateral external ophthalmoplegia, ataxia and long tract signs. Although the pathophysiology is not fully understood, it has been associated with anti-GQ1b antibodies in two-thirds of patients. We present a patient with clinical features consistent with BBE and positive anti-GM1 and anti-GD1a antibodies. A diagnostic approach to the acutely unwell patient with brainstem encephalitis is explored in this clinical context with a literature review of the aforementioned ganglioside antibody significance. Intravenous immunoglobulin therapy is highlighted in BBE using up-to-date evidence-based extrapolation from GBS.

Paroxysmal dysarthria-ataxia syndrome: Literature review on MRI findings and report of a peculiar case with clinically isolated syndrome coexisting with anti-N-methyl-d-aspartate receptor antibodies.

Paroxysmal dysarthria and ataxia (PDA) syndrome constitutes a rare neurological disorder, and is generally reported in cases of multiple sclerosis (MS) involving the midbrain. We present an illustrative case of 32-year-old female who developed clinically isolated syndrome manifested paroxysmal dysarthria, ataxia, ptosis and diplopia, coexisting with anti-N-methyl-d-aspartate receptor antibodies. We review the literature and identify 23 other cases with brain MRI examinations to summarize the lesion locations and clinical characteristics of PDA syndrome, and ultimately provide a new framework for understanding this rare condition. The current case expands the spectrum of symptoms in PDA syndrome, which was including but not limited to dysarthria and ataxia. Caudal paramedian midbrain lesions involving decussation of the superior cerebellar peduncles appear to be critical for PDA syndrome.

Fetal coenzyme Q10 deficiency in intrahepatic cholestasis of pregnancy.

AIM: Intrahepatic cholestasis of pregnancy (ICP) is considered a high-risk condition because it may have serious consequences for the fetus health. ICP is characterized by the accumulation of bile acids in maternal serum which contribute to an imbalance between the production of reactive oxygen species and the antioxidant defenses increasing the oxidative stress experienced by the fetus. Previously, it was reported a significant decrease in plasma coenzyme Q10 (CoQ10) in women with ICP. CoQ10 is a redox substance integrated in the mitochondrial respiratory chain and is recognized as a potent antioxidant playing an intrinsic role against oxidative damage. The objective of the present study was to investigate the levels of CoQ10 in umbilical cord blood during normal pregnancy and in those complicated with ICP, all of them compared to the maternal ones. METHODS: CoQ10 levels and bile acid levels in maternal and umbilical cord blood levels during normal pregnancies (n=23) and in those complicated with ICP (n=13), were investigated. RESULTS: A significant decrease in neonate CoQ10 levels corrected by cholesterol (0.105±0.010 vs. 0.069±0.011, P<0.05, normal pregnancy vs. ICP, respectively), together with an increase of total serum bile acids (2.10±0.02 vs. 7.60±2.30, P<0.05, normal pregnancy vs. ICP, respectively) was observed. CONCLUSIONS: A fetus from an ICP mother is exposed to a greater risk derived from oxidative damage. The recognition of CoQ10 deficiency is important since it could be the starting point for a new and safe intervention strategy which can establish CoQ10 as a promising candidate to prevent the risk of oxidative stress.

Allopregnanolone Treatment Improves Plasma Metabolomic Profile Associated with GABA Metabolism in Fragile X-Associated Tremor/Ataxia Syndrome: a Pilot Study.

Currently, there is no effective treatment for the fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset neurodegenerative disorder. In this pilot study, we evaluated whether allopregnanolone, a natural neurosteroid that exerts beneficial effects in neurodegenerative diseases, nervous system injury, and peripheral neuropathies, could improve lymphocytic bioenergetics and plasma pharmacometabolomics in six males with FXTAS (68 ± 3 years old; FMR1 CGG repeats 94 ± 4; FXTAS stages ranging from 3 to 5) enrolled in a 12-week open-label intervention study conducted at the University of California Davis from December 2015 through July 2016. Plasma pharmacometabolomics and lymphocytic mitochondria function were assessed at baseline (on the day of the first infusion) and at follow-up (within 48 h from the last infusion). In parallel, quantitative measurements of tremor and ataxia and neuropsychological evaluations of mental state, executive function, learning, memory, and psychological symptoms were assessed at the same time points. Allopregnanolone treatment impacted significantly GABA metabolism, oxidative stress, and some of the mitochondria-related outcomes. Notably, the magnitude of the individual metabolic response, as well as the correlation with some of the behavioral tests, was overwhelmingly carrier-specific. Based on this pilot study, allopregnanolone treatment has the potential for improving cognitive and GABA metabolism in FXTAS aligned with the concept of precision medicine.

Neurotrophin Expression in Lymphocytes: a Powerful Indicator of Degeneration in Parkinson's Disease, Amyotrophic Lateral Sclerosis and Ataxia.

Deregulated neurotrophin is an etiological factor in the pathology of neurodegenerative diseases (ND) that are clinically different entities but characterised by similar limb dysfunction. Earlier validation of peripheral biomarkers can provide significant translational benefit to ND patients. We analysed brain-derived neurotrophic factor (BDNF)-tropomyosin possessing tyrosine-related kinase (Trk B) and its key downstream proteins which are implicated in ND such as Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and ataxia. Blood from ND patients with PD, ALS and Ataxia with movement dysfunctions were obtained to analyse mRNA and protein expressions of the above mentioned factors in lymphocytes. The mRNA and protein expression of BDNF-Trk B and its key downstream molecules showed a significant variation when compared to control and among NDs. The study intends to show that on identifying the variation of these key molecules in the blood samples of patients with ND can serve as early diagnostic candidates. Thus by intervening, the neurotrophins and their pathways can help in early diagnosis and optimising levels of diagnostic certainty.

Single-step blood direct PCR: A robust and rapid method to diagnose triplet repeat disorders.

OBJECTIVE: DNA extraction prior to polymerase chain reaction (PCR) amplification in genetic diagnoses of triplet repeat disorders (TRDs) is tedious and labour-intensive and has the limitations of sample contamination with foreign DNA, including that from preceding samples. Therefore, we aimed to develop a rapid, robust, and cost-effective method for expeditious genetic investigation of TRDs from whole blood as a DNA template. METHODS: Peripheral blood samples were collected from 70 clinically suspected patients of progressive ataxia. The conventional method using genomic DNA and single-step Blood-Direct PCR (BD-PCR) method with just 2µl of whole blood sample were tested to amplify triplet repeat expansion in genes related to spinocerebellar ataxia (SCA) types 1, 2, 3, 12 and Friedreich's ataxia (FRDA). Post-PCR, the allele sizes were mapped and repeat numbers were calculated using GeneMapper and macros run in Microsoft Excel programmes. RESULTS: Successful amplification of target regions was achieved in all samples by both methods. The frequency of the normal and mutated allele was concordant between both methods, diagnosing 37% positive for a mutation in either of the candidate genes. The BD-PCR resulted in higher intensities of product peaks of normal and pathogenic alleles. CONCLUSIONS: The nearly-accurate sizing of the normal and expanded allele was achieved in a shorter time (4-5h), without DNA extraction and any risk of cross contamination, which suggests the BD-PCR to be a reliable, inexpensive, and rapid method to confirm TRDs. This technique can be introduced in routine diagnostic procedures of other tandem repeat disorders.

Unexplained spikes in lamotrigine serum concentration: nonlinear elimination?

OBJECTIVES: The objective of this study was to evaluate possible nonlinear lamotrigine (LTG) pharmacokinetics at elevated concentration. LTG is reported to have linear kinetics, so that elimination rate is linearly proportional to blood concentration and a change in dose is accompanied by a proportionate change in serum concentration. We encountered patients in whom LTG serum concentration increased dramatically in response to minor or no change in LTG dose. We studied this phenomenon in patients with LTG toxicity in one clinic. MATERIALS AND METHODS: Using electronic medical records from 1997 to 2014, we identified patients who developed clinical LTG toxicity with LTG serum concentrations >20 mg/l, after tolerating lamotrigine at lower serum concentrations. We reviewed LTG dose change and other changes that preceded the episode of toxicity. RESULTS: Twenty-two patients had at least one episode of LTG toxicity with levels higher than 20 mg/l (of 922 patients with available levels). The peak serum concentration varied from 21.1 to 40.3 mg/l (mean 28.7). The increase in level was explained in three patients (post-delivery in one, addition of valproate in two). In the 18 others, the increase was not explained or it was disproportionate to an increase in LTG dose. CONCLUSIONS: Spikes in LTG levels and associated clinical toxicity may occur unexpectedly, suggesting that elimination kinetics may be nonlinear in some individuals at serum concentrations in the upper range. Measurement and close monitoring of LTG levels is warranted for new symptoms that could be consistent with lamotrigine toxicity, particularly when the baseline serum concentration has been >10 mg/l.

Novel Blood Biomarkers Are Associated with White Matter Lesions in Fragile X- Associated Tremor/Ataxia Syndrome.

BACKGROUND: The need for accessible cellular biomarkers of neurodegeneration in carriers of the fragile X mental retardation 1 (FMR1) premutation (PM) alleles. OBJECTIVE: To assess the mitochondrial status and respiration in blood lymphoblasts from PM carriers manifesting the fragile X-associated tremor/ataxia syndrome (FXTAS) and non-FXTAS carriers, and their relationship with the brain white matter lesions. METHODS: Oxygen consumption rates (OCR) and ATP synthesis using a Seahorse XFe24 Extracellular Flux Analyser, and steady-state parameters of mitochondrial function were assessed in cultured lymphoblasts from 16 PM males (including 11 FXTAS patients) and 9 matched controls. The regional white matter hyperintensity (WMH) scores were obtained from MRI. RESULTS: Mitochondrial respiratory activity was significantly elevated in lymphoblasts from PM carriers compared with controls, with a 2- to 3-fold increase in basal and maximum OCR attributable to complex I activity, and ATP synthesis, accompanied by unaltered mitochondrial mass and membrane potential. The changes, which were more advanced in FXTAS patients, were significantly associated with the WMH scores in the supratentorial regions. CONCLUSION: The dramatic increase in mitochondrial activity in lymphoblasts from PM carriers may represent either the early stages of disease (specific alterations in short-lived blood cells) or an activation of the lymphocytes under pathological situations. These changes may provide early, convenient blood biomarkers of clinical involvements.

Elevated mercury bound to serum proteins in methylmercury poisoned rats after selenium treatment.

Methylmercury is a toxic pollutant and is generated by microbial methylation of elemental or inorganic mercury in the environment. Previous study found decreased hepatic MDA levels and urinary mercury levels in methylmercury poisoned rats after sodium selenite treatment. This study further found increased mercury levels in serum samples from methylmercury poisoned rats after selenium treatment. By using size exclusion chromatography coupled to inductively coupled plasma mass spectrometry, three Hg- binding protein fractions and two Se-binding protein fractions were identified with the molecular weight of approximately 21, 40, and 75 kDa and of 40 and 75 kDa, respectively. Elevated mercury level in the 75 kDa protein fraction was found binding with both Hg and Se, which may explain the decreased urinary Hg excretion in MeHg poisoned rats after Se treatment. MALDI-TOF-MS analysis of the serum found that the 75 kDa protein fractions were albumin binding with both Hg and Se and the 21 kDa fraction was Hg- binding metallothionein.

ß-glucuronidase mRNA levels are correlated with gait and working memory in premutation females: understanding the role of FMR1 premutation alleles.

Fragile X tremor ataxia syndrome (FXTAS) is a late-onset disorder manifesting in a proportion of FMR1 premutation individuals (PM: 55-199 CGG triplet expansions). FXTAS is associated with elevated levels of FMR1 mRNA which are toxic. In this study, relationships between neurocognitive and intra-step gait variability measures with mRNA levels, measured in blood samples, were examined in 35 PM and 35 matched control females. The real-time PCR assays measured FMR1 mRNA, and previously used internal control genes: ß-Glucuronidase (GUS), Succinate Dehydrogenase 1 (SDHA) and Eukaryotic Translation Initiation Factor 4A (EI4A2). Although there was significant correlation of gait variability with FMR1 mRNA levels (p = 0.004) when normalized to GUS (FMR1/GUS), this was lost when FMR1 was normalized to SDHA and EI4A2 (2IC). In contrast, GUS mRNA level normalized to 2IC showed a strong correlation with gait variability measures (p < 0.007), working memory (p = 0.001) and verbal intelligence scores (p = 0.008). PM specific changes in GUS mRNA were not mediated by FMR1 mRNA. These results raise interest in the role of GUS in PM related disorders and emphasise the importance of using appropriate internal control genes, which have no significant association with PM phenotype, to normalize FMR1 mRNA levels.

Skewed X Inactivation in Women Carrying the FMR1 Premutation and Its Relation with Fragile-X-Associated Tremor/Ataxia Syndrome.

BACKGROUND: Fragile-X-associated tremor/ataxia syndrome (FXTAS) is a late-onset multisystem neurological disorder characterized by intention tremor and cerebellar ataxia. OBJECTIVE: We hypothesized that in FMR1 premutation females with FXTAS, a normal X chromosome might more frequently be inactivated; therefore, the aim of this study was to determine the relationship between skewed X chromosome inactivation (XCI) and FXTAS. METHODS: We studied the XCI patterns of cases of FMR1 premutation in 10 women with FXTAS and 21 without FXTAS. RESULTS: The distribution of XCI patterns in the FXTAS and no-FXTAS groups showed differences regarding the allele presenting severe skewed XCI. In the FXTAS group, all cases preferentially inactivated the non-expanded X chromosome, whereas in the no-FXTAS group, all inactivated the expanded X chromosome. Nevertheless, no significant differences were found on comparing XCI frequencies among FMR1 premutation carriers with and without FXTAS. As expected, we found statistically significant differences in the skewed XCI on comparing FMR1 premutation women and controls. CONCLUSION: Although the reduced sample size and blood XCI patterns are two limitations of this study, our results suggest that the skewed XCI of the normal FMR1 allele may be a risk factor for the development of FXTAS. Furthermore, our findings also support the protective effect of the expression of a normal FMR1 allele.

Anti-GQ1b antibody syndrome: anti-ganglioside complex reactivity determines clinical spectrum.

BACKGROUND AND PURPOSE: Anti-GQ1b antibodies have been found in patients with Miller Fisher syndrome as well as its related conditions. Our aim was to identify the mechanism by which autoantibodies produce various clinical presentations in 'anti-GQ1b antibody syndrome'. METHODS: Immunoglobulin G antibodies to ganglioside complex (GSC) of GQ1b or GT1a with GM1, GD1a, GD1b or GT1b were tested in sera from patients with anti-GQ1b (n = 708) or anti-GT1a (n = 696) IgG antibodies. Optical densities of the single anti-GQ1b or anti-GT1a antibodies were used as reference (100%), and those of anti-GSC antibodies were expressed in percentages to reference. The relationships between anti-GSC antibody reactivity and the corresponding clinical features were assessed by multivariate logistic regression analysis. RESULTS: Ophthalmoplegia and hypersomnolence were significantly associated with complex-attenuated anti-GQ1b and anti-GT1a antibodies. Ataxia was associated with GD1b- and GT1b-enhanced anti-GQ1b antibodies or GM1-enhanced anti-GT1a antibodies. Bulbar palsy was associated with GT1b-enhanced anti-GQ1b antibodies. Neck weakness was associated with GD1a-enhanced anti-GQ1b antibodies. Arm weakness was associated with GD1b-enhanced anti-GQ1b and GD1a-enhanced anti-GT1a antibodies. Leg weakness was associated with GD1a-enhanced anti-GQ1b and anti-GT1a antibodies. CONCLUSIONS: Differences in fine specificity of anti-GQ1b antibodies are associated with clinical features, possibly due to the different expression of gangliosides in different parts of the nervous system.

A novel non-invasive sampling method using buccal mucosa cells for determination of coenzyme Q10.

Coenzyme Q10 (CoQ10) is an important cofactor in the mitochondrial respiratory chain and a potent endogenous antioxidant. CoQ10 deficiency is often associated with numerous diseases, and patients can benefit from CoQ10 supplementation, being more effective when diagnosed and treated early. Due to the increased interest in CoQ10 deficiency, several methods for CoQ10 analysis from plasmatic, muscular, fibroblast, and platelet matrices have been developed. These sampling techniques are not only highly invasive but also too traumatic for periodic clinical monitoring. In the present work, we describe the development and validation of a novel non-invasive sampling method for quantification of CoQ10 in buccal mucosa cells (BMCs) by microHPLC. This method is suitable for using in a routine laboratory and useful for sampling patients in pediatry. CoQ10 correlation was demonstrated between BMCs and plasma levels (Spearman r, 0.4540; p < 0.001). The proposed method is amenable to be applied in the post treatment monitoring, especially in pediatric patients as a non-invasive sample collection. More studies are needed to assess whether this determination could be used for diagnosis and if this matrix could replace the traditional ones.

Contactin 1 IgG4 associates to chronic inflammatory demyelinating polyneuropathy with sensory ataxia.

A Spanish group recently reported that four patients with chronic inflammatory demyelinating polyneuropathy carrying IgG4 autoantibodies against contactin 1 showed aggressive symptom onset and poor response to intravenous immunoglobulin. We aimed to describe the clinical and serological features of Japanese chronic inflammatory demyelinating polyneuropathy patients displaying the anti-contactin 1 antibodies. Thirteen of 533 (2.4%) patients with chronic inflammatory demyelinating polyneuropathy had anti-contactin 1 IgG4 whereas neither patients from disease or normal control subjects did (P = 0.02). Three of 13 (23%) patients showed subacute symptom onset, but all of the patients presented with sensory ataxia. Six of 10 (60%) anti-contactin 1 antibody-positive patients had poor response to intravenous immunoglobulin, whereas 8 of 11 (73%) antibody-positive patients had good response to corticosteroids. Anti-contactin 1 IgG4 antibodies are a possible biomarker to guide treatment option.

Intracisternal cyclodextrin prevents cerebellar dysfunction and Purkinje cell death in feline Niemann-Pick type C1 disease.

Niemann-Pick type C1 (NPC) disease is a lysosomal storage disease caused by mutations in the NPC1 gene, leading to an increase in unesterified cholesterol and several sphingolipids, and resulting in hepatic disease and progressive neurological disease. We show that subcutaneous administration of the pharmaceutical excipient 2-hydroxypropyl-ß-cyclodextrin (HPßCD) to cats with NPC disease ameliorated hepatic disease, but doses sufficient to reduce neurological disease resulted in pulmonary toxicity. However, direct administration of HPßCD into the cisterna magna of presymptomatic cats with NPC disease prevented the onset of cerebellar dysfunction for greater than a year and resulted in a reduction in Purkinje cell loss and near-normal concentrations of cholesterol and sphingolipids. Moreover, administration of intracisternal HPßCD to NPC cats with ongoing cerebellar dysfunction slowed disease progression, increased survival time, and decreased the accumulation of brain gangliosides. An increase in hearing threshold was identified as a potential adverse effect. These studies in a feline animal model have provided critical data on efficacy and safety of drug administration directly into the central nervous system that will be important for advancing HPßCD into clinical trials.

Primary coenzyme Q10 deficiency presenting as fatal neonatal multiorgan failure.

Coenzyme Q10 deficiency is a clinically and genetically heterogeneous disorder, with manifestations that may range from fatal neonatal multisystem failure, to adult-onset encephalopathy. We report a patient who presented at birth with severe lactic acidosis, proteinuria, dicarboxylic aciduria, and hepatic insufficiency. She also had dilation of left ventricle on echocardiography. Her neurological condition rapidly worsened and despite aggressive care she died at 23 h of life. Muscle histology displayed lipid accumulation. Electron microscopy showed markedly swollen mitochondria with fragmented cristae. Respiratory-chain enzymatic assays showed a reduction of combined activities of complex I+III and II+III with normal activities of isolated complexes. The defect was confirmed in fibroblasts, where it could be rescued by supplementing the culture medium with 10 µM coenzyme Q10. Coenzyme Q10 levels were reduced (28% of controls) in these cells. We performed exome sequencing and focused the analysis on genes involved in coenzyme Q10 biosynthesis. The patient harbored a homozygous c.545T>G, p.(Met182Arg) alteration in COQ2, which was validated by functional complementation in yeast. In this case the biochemical and morphological features were essential to direct the genetic diagnosis. The parents had another pregnancy after the biochemical diagnosis was established, but before the identification of the genetic defect. Because of the potentially high recurrence risk, and given the importance of early CoQ10 supplementation, we decided to treat with CoQ10 the newborn child pending the results of the biochemical assays. Clinicians should consider a similar management in siblings of patients with CoQ10 deficiency without a genetic diagnosis.

GD1b-specific antibodies may bind to complex of GQ1b and GM1, causing ataxia.

Monospecific IgG antibodies to GD1b ganglioside (GD1b-specific antibodies) have been found in patients with acute ataxic neuropathy and Guillain-Barré syndrome, but the association of the GD1b-specific antibodies with specific neurological conditions has yet to be established. We tested sera from more than 10,000 patients with various neurological disorders, and found six sera, which contained IgG antibodies to GD1b, but not to LM1, GM1, GM1b, GD1a, GalNAc-GD1a, GT1a, GT1b and GQ1b. All six patients who carried GD1b-specific antibodies presented with acute onset of ataxia and monophasic course of the illness, of whom five demonstrated cerebellar-like ataxia. Four patients had antecedent symptoms of upper respiratory tract infection. The six patients demonstrated areflexia, and four complained of distal numbness. All the six patients who had the GD1b-specific antibodies carried IgG antibodies to complex of GQ1b/GM1 and GT1a/GM1. GD1b-specific antibodies were significantly absorbed by GQ1b/GM1 and GT1a/GM1 and anti-GQ1b/GM1 and -GT1a/GM1 antibodies were absorbed by GD1b. In conclusion, the GD1b-specific antibodies, which recognizes GQ1b/GM1 or GT1a/GM1 complex, are associated with acute ataxia.