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Background: Deep brain stimulation (DBS) in Parkinson’s disease (PD) requires extensive trial-and-error programming, often taking over a year to optimize. An objective, rapid biomarker of stimulation success is needed. Our team developed a functional magnetic resonance imaging (fMRI)-based algorithm to identify optimal DBS settings. This study prospectively compared fMRI-guided programming with standard-of-care (SoC) clinical programming in a double-blind, crossover, non-inferiority trial. Methods: Twenty-two PD-DBS patients were prospectively enrolled for fMRI using a 30-sec DBS-ON/OFF cycling paradigm. Optimal settings were identified using our published classification algorithm. Subjects then underwent >1 year of SoC programming. Clinical improvement was assessed under SoC and fMRI-determined stimulation conditions. Results: fMRI optimization significantly reduced the time required to determine optimal settings (1.6 vs. 5.6 months, p<0.001). Unified Parkinson’s Disease Rating Scale (UPDRSIII) improved comparably with both approaches (23.8 vs. 23.6, p=0.9). Non-inferiority was demonstrated within a predefined margin of 5 points (p=0.0018). SoC led to greater tremor improvement (p=0.019), while fMRI showed greater bradykinesia improvement (p=0.040). Conclusions: This is the first prospective evaluation of an algorithm able to suggest stimulation parameters solely from the fMRI response to stimulation. It suggests that fMRI-based programming may achieve equivalent outcomes in less time than SoC, reducing patient burden while potentially enhancing bradykinesia response.
Background: Self-injurious behaviours (SIB) are repetitive, non-accidental movements that result in physical damage inflicted upon oneself, without suicidal intent. SIB are prevalent among children with autism spectrum disorder and can lead to permanent disability or death. Neuromodulation at a locus of neural circuitry implicated in SIB, the nucleus accumbens (NAc), may directly influence these behaviours. Methods: We completed a phase I, open-label clinical trial of deep brain stimulation (DBS) of the NAc in children with severe, treatment-refractory SIB (ClinicalTrials.gov NCT03982888). Participants were monitored for 12 months following NAc-DBS to assess the primary outcomes of safety and feasibility. Secondary outcomes included serial assessments of SIB, ambulatory actigraphy, and changes in brain glucose metabolism induced by DBS. Results: Six children underwent NAc-DBS without any serious adverse events. NAc-DBS resulted in significant reductions in SIB and SIB-associated behaviours across multiple standardized scales, concurrent with clinically meaningful improvements in quality-of-life. Ambulatory actigraphy showed reductions in high-amplitude limb movements and positron emission tomography revealed treatment-induced reductions in metabolic activity within the thalamus, striatum, and temporoinsular cortex. Conclusions: This first-in-children phase 1 clinical trial demonstrates the safety and feasibility of NAc-DBS in children with severe, refractory SIB at high risk of physical injury and death and supports further investigations.
The success of deep brain stimulation (DBS) relies on applying carefully titrated therapeutic stimulation at specific targets. Once implanted, the electrical stimulation parameters at each electrode contact can be modified. Iteratively adjusting the stimulation parameters enables testing for the optimal stimulation settings. Due to the large parameter space, the currently employed empirical testing of individual parameters based on acute clinical response is not sustainable. Within the constraints of short clinical visits, optimization is particularly challenging when clinical features lack immediate feedback, as seen in DBS for dystonia and depression and with the cognitive and axial side effects of DBS for Parkinson’s disease. A personalized approach to stimulation parameter selection is desirable as the increasing complexity of modern DBS devices also expands the number of available parameters. This review describes three emerging imaging and electrophysiological methods of personalizing DBS programming. Normative connectome-base stimulation utilizes large datasets of normal or disease-matched connectivity imaging. The stimulation location for an individual patient can then be varied to engage regions associated with optimal connectivity. Electrophysiology-guided open- and closed-loop stimulation capitalizes on the electrophysiological recording capabilities of modern implanted devices to individualize stimulation parameters based on biomarkers of success or symptom onset. Finally, individual functional MRI (fMRI)-based approaches use fMRI during active stimulation to identify parameters resulting in characteristic patterns of functional engagement associated with long-term treatment response. Each method provides different but complementary information, and maximizing treatment efficacy likely requires a combined approach.
Deep brain stimulation (DBS) is one of the most effective tools in the treatment of Parkinson’s disease. Being a last-resort therapy for many years, it recently advanced to a valuable option in moderate and even earlier stages. Different nuclei of the basal ganglia have been successfully targeted with various effects, risks and stimulation-induced side effects. Advances in implantation technique and accuracy, neuroimaging and implant technology helped make DBS a mostly safe and successful procedure, although the full potential of recent technical advantages such as directional stimulation, brain sensing or remote programming have yet to be fully explored.
During the first thousand days of life, fetus and infant’s nutrition depends on mother’s diet. Polyunsaturated fatty acids (PUFA) are important substrates in infant neurogenesis. We related erythrocyte membrane (EM) and breast milk fatty acids (FA) profile in lactating mothers with the EM FA profile in exclusively breastfed infants and evaluated maternal fat consumption. We conducted an observational, cross-sectional analytical study. During the 2016–2019 period, milk and blood samples from adult mothers 90 days post-partum and infant’s blood were analysed, and FA were determined by GC. A frequency of consumption survey of fatty acids precursor foods and sources was conducted. The sample included forty-five mother–infant EM and forty-five milk samples donated by the same mothers. A low percentage of DHA (0·14 (0·12–0·2)) was found in milk, consistent with mother’s low consumption of DHA-rich foods. A significant positive correlation between infant’s EM DHA percentage and milk DHA percentage (r = 0·39; P value 0·008), as well as between infant’s EM ω-3 fatty acids sum and milk DHA percentage (r = 0·39; P value 0·008), was found. When milk had a DHA percentage greater than or equal to 0·20 %, infants had a significant increase in DHA in their EM. Mother’s consumption of DHA precursors and sources was NS. The relation between the DHA percentage distribution found in maternal milk, and the DHA percentage distribution found in infant’s and mother’s EM was proven in this population. Dietary fatty acid intake is associated with the maternal milk lipid distribution and with mothers’ and infant’s EM fatty acids percentage.
Background: Deep Brain Stimulation (DBS) has become increasingly prevalent in the management of paediatric movement disorders, with the globus pallidus interna (GPi) serving as the most utilized target. However, limitations exist, including variable responses in genetic versus acquired forms of movement disorder and structural damage in the GPi would preclude its use as a target. Given these limitations, there is a pressing need to explore alternative targets. We investigated the application of non-GPi targets in paediatrics through a systematic review. Methods: Individual data points were gathered from references identified through a systematic electronic search and analysed descriptively. We included paediatric patients (0-18 years) with movement disorders who underwent non-GPi-DBS. We excluded adults and other indications. Results: Preliminarily, 64 patients were identified from 40 references. Dystonia was the most common movement disorder type, followed by tremor and chorea. The subthalamic nucleus was the frequent DBS target for dystonia, yielding promising outcomes of improvement as measured on the Burke-Fahn-Marsden movement scale ranging from 43% to 95%. The ventral intermediate nucleus was the second most employed target, demonstrating favourable results. Conclusions: Non-pallidal DBS targets hold promise as potentially efficient and safe. However, to further validate their effectiveness and safety, larger multi-centre randomized studies are required.
Background: Subthalamic nucleus (STN) deep brain stimulation (DBS) improves the cardinal symptoms of Parkinson’s disease (PD). However, the therapeutic mechanisms are incompletely understood. By leveraging patient-specific brain responses to DBS using functional magnetic resonance imaging (fMRI) acquired during stimulation, we identify and validate symptom-specific networks associated with clinical improvement. Methods: Forty PD patients with STN-DBS were enrolled for fMRI using a 30-sec DBS-ON/OFF cycling paradigm. The four cardinal motor outcomes of PD were chosen a priori and measured using the Movement Disorder Society-Sponsored Revision of the Unified Parkinson’s Disease Rating Scale, part III (MDS-UPDRSIII): axial instability, tremor, rigidity, bradykinesia. Stimulation-dependent changes in blood oxygen level-dependent (BOLD) signal were correlated with each symptom. Results: The relationship between BOLD response and outcomes revealed significant networks of clinical response (p<0.001). Using BOLD responses from the network hubs, each symptom-specific model was significantly predictive of actual improvement: axial instability (R2=0.38, p=0.000026), bradykinesia (R2=0.29, p=0.00033), rigidity (R2=0.40, p=0.000013), tremor (R2=0.26, p=0.00073). Conclusions: Using patient-specific imaging, we provide evidence of an association between DBS-evoked fMRI response and individual symptom improvement. Brain networks associated with clinical improvement were different depending on the PD symptom examined, suggesting the presence of symptom-specific networks of efficacy which may allow personalization of DBS therapy.
Background: Success of deep brain stimulation (DBS) in Parkinson’s disease (PD) relies on time-consuming trial-and-error testing of stimulation settings. Here, we prospectively compared an fMRI-based stimulation optimization algorithm with >1 year of standard-of-care (SoC) programming in a double-blind, crossover, non-inferiority trial. Methods: Twenty-seven PD-DBS patients were prospectively enrolled for fMRI using a 30-sec DBS-ON/OFF cycling paradigm. Optimal settings were identified using our published classification algorithm. Subjects then underwent >1 year of SoC programming. Clinical improvement was assessed, after an overnight medication washout period, under SoC and fMRI-determined stimulation conditions. A predefined non-inferiority margin was -5 points on the Unified Parkinson’s Disease Rating Scale (UPDRSIII). Results: UPDRSIII improved from 45.3 (SD=14.6) at baseline to 24.9 (SD=10.9) and 24.1 (SD=10.9) during SoC and fMRI-determined stimulation, respectively. The mean difference in scores was 0.8 (SD=8.5; 95% CI -4.5 to 6.2). The non-inferiority margin was not contained within the 95% confidence interval, establishing non-inferiority (p=0.013). Conclusions: This is the first prospective evaluation of an algorithm able to suggest stimulation parameters solely from the fMRI response to stimulation. It suggests equivalent outcomes may be achieved in 3 hours of fMRI scanning immediately after surgery compared to SoC requiring 6 or more in-person clinic visits throughout >1 year.
Reduced hearing is associated with increased risk for social, emotional, and behavioral difficulties. Studies to date have typically compared DHH children with their hearing peers without regard for unilateral hearing loss (UHL) versus bilateral hearing loss (BHL). Children with UHL are often perceived as more like their typically hearing peers than their peers with BHL. Children with UHL typically access sound and spoken language which facilitates their functioning with fewer supports (e.g., interpreters, captioning). These children, however, show cognitive, academic, and communication profiles more similar to children with BHL than typically hearing peers. They may also experience similar social, emotional, and behavioral challenges as their BHL peers. We examined social, emotional, and behavioral functioning in a clinically referred sample of children with UHL versus BHL.
Participants and Methods:
Parents of 100 children aged 2 to 17 years (M=7.12) with either UHL (n=30) or BHL (n=70) completed the Behavioral Assessment System for Children, Third Edition (BASC-3) as part of neuropsychological evaluation in a Deaf and Hard of Hearing Program within a tertiary pediatric hospital. BASC-3 scores based on General Combined norms were compared to an expected distribution of typically developing hearing children using non-parametric one-sample tests. Profiles of scores for children with UHL and BHL were examined in a repeated measures MANOVA.
Results:
The groups of children with UHL and BHL showed similar age, gender, race, ethnicity, and Area Deprivation Index compositions. Eighty four percent of BHL children communicated with spoken language, and 100% of UHL children communicated with spoken language (p=.02). There were similar rates of comorbid diagnoses for ADHD (20%), Anxiety/Depression (18%), Autism Spectrum Disorder (8%), and Intellectual Disability/Global Developmental Delay (9%). However, children with BHL tended to be at greater risk for Language Disorders (50%) than those with UHL (30%, = 3.41 p=.065). Together, children with hearing loss showed significantly higher scores on the BASC-3 Hyperactivity, Aggression, Attention Problems, Atypicality, and Withdrawal clinical scales than expected (One-Sample Kolmogorov-Smirnov Test; p<.01). Profile analysis showed that children with any type of hearing loss had a varied pattern of scores across scales (F(7,686)=4.33, p<.01), with highest scores on Hyperactivity and Attention Problems scales and lowest scores on Somatization. Scale profiles did not differ, however, between UHL and BHLgroups (p=.127).
Conclusions:
Children with UHL have access to auditory input, typically enabling early language development more like their hearing peers compared to children with BHL. In turn, these children may be overlooked more so than their BHL peers. However, the likelihood of social, emotional, and behavioral difficulties is similar between the two groups of children with hearing loss, whether that is unilateral or bilateral. Our study showed both groups of children had similar profiles across BASC-3 scales with elevations relative to norms. Measuring these everyday functions in children with hearing loss is important for early detection of risks to promote early intervention.
Children with unilateral hearing loss (UHL) have difficulty hearing in noisy environments and localizing sounds, impacting learning and social opportunities across contexts. Using a visible device like a cochlear implant (CI) may improve functioning but can also create psychological risk. Audiological measures alone are insufficient for predicting social, emotional, educational, adaptive, and quality-of-life post-operative outcomes, which are highly variable in this population and can also be impacted by a secondary diagnosis. Extending beyond audition to consider the “whole child” through neuropsychological evaluation may produce a sharper picture of potential outcomes, with or without surgical/audiological intervention. Given recent FDA approval for CI in children with UHL, more are receiving this elective surgery despite difficulties predicting who will experience significant benefit. Here we describe neuropsychological profiles of children with UHL who underwent CI candidacy evaluation at a tertiary pediatric hospital.
Participants and Methods:
During pre-operative clinical care, CI candidates completed targeted neuropsychological evaluation to identify patient- and family-level factors that could impact CI use and outcomes from surgery. Cognitive, language, attention/executive, visuoperceptual/visuomotor, academic, adaptive, and emotional/behavioral functioning were assessed. Evaluations integrated history, observations, caregiver report forms, and performance-based test data.
Results:
18 individuals were evaluated (age 7-months to 16-years). Most had left-sided UHL (67%) and were male (61%). Known hearing loss etiologies were congenital cytomegalovirus (n=5), enlarged vestibular aqueduct (n=1), traumatic brain injury (n=1), meningitis (n=1), cholesteatoma (n=1), neurofibromatosis type 1 (n=1), and Waardenburg syndrome (n=1). Indices of general cognitive ability were generally low average to average. Patterns of cognitive impairment were not restricted to language-based tasks (e.g., Beery VMI-6 range 56-109, M=89.42, SD=16.27). Standardized parent ratings of everyday executive functioning, social/emotional/behavioral functioning, and adaptive skills were collected. Eight (44%) had a behavioral health diagnosis: Attention Deficit Hyperactivity Disorder (n=2), Global Developmental Delay (n=2), Unspecified Neurodevelopmental Disorder (n=2), Autism Spectrum Disorder (n=1), and Depression (n=1). Thirteen (72%) received or will receive a CI, of whom 38% had a behavioral health diagnosis. Average Area Deprivation Index (a marker of socio-economic status) was lower for individuals who ultimately received CIs (M=18%tile) compared to those who did not (M=25%tile).
Conclusions:
There may be increased rates of neurodevelopmental/psychological conditions among children with UHL, especially when the etiology involves the central nervous system. Albeit preliminary, results align with findings from bilateral hearing loss samples. Findings highlight the importance of routine neuropsychological screening in children with UHL and close interdisciplinary collaboration for optimal outcomes. Socio-economic disparities among those who do and do not receive CI need further exploration as those who did not receive CIs tended to be from less resourced neighborhoods. Additional research is warranted to understand the full range of risk and protective factors for children with UHL and how these relate to outcomes for those who opt for cochlear implantation.
Standardized assessment measures can provide data to inform a diagnosis of Autism Spectrum Disorder (ASD). Most measures assessing ASD characteristics rely on some degree of behavioral response to sound (e.g., responding to name, demonstrating listening response), and are often not appropriate for use with children who are Deaf and Hard of Hearing (DHH), especially with individuals who use signed languages. Few studies have reported on the Behavioral Assessment System for Children, Third Edition (BASC-3) for DHH children, and we aim to describe BASC-3 profiles in children with ASD who are DHH.
Participants and Methods:
Participants include eight DHH patients diagnosed with ASD through interdisciplinary team evaluations by developmental-behavioral pediatricians, speech-language pathologists, and neuropsychologists with expertise in DHH child development. Demographics include a mean age of 6.17 years, and 62.5% were Male. Self-reported racial distribution was 75% White, 12.5% Black and 12.5% declined to answer. Average Area Deprivation Index (marker of socioeconomic status) was 32.13%tile. As a part of the evaluation, parents rated their children using the BASC-3. Languages include spoken English (75%) and American Sign Language (25%). Relevant co-occurring
neurodevelopmental/psychological diagnoses include Global Developmental Delay (n=1), Moderate Intellectual Disability (n=1), and Depression (n=1). Types of hearing loss include sensorineural (75%), conductive (12.5%), and mixed (12.5%). Three participants had different degrees of bilateral hearing loss in each ear: mild sloping-severe, moderate rising-mild (n=1), profound, moderate rising-normal level (n=1), and profound, moderate (n=1). Four participants had the same level of hearing loss in both ears: moderate-moderately severe (n=1), moderately severe-severe (n=1), severe-profound (n=1), and profound (n=1). One child had a unilateral moderate hearing loss. Technology utilized: unilateral hearing aid (n=2), bilateral hearing aids (n=2), unilateral cochlear implant (n=1), bilateral cochlear implants (n=2), and bimodal technology (n=1). BASC-3 scales of interest in this study were the developmental social disorders scale (DSD), Autism probability index (AUI), clinical scales, and adaptive scales. BASC-3 scores were standardized using General Combined norms and means were plotted.
Results:
BASC-3 mean scores on clinical scales were elevated (T>60) on Atypicality (M=71), Hyperactivity (M=63), Withdrawal (M=63), and Attention Problems (M=65) in children with ASD who are DHH in this sample. BASC-3 mean scores on adaptive scales were below threshold (T<40) on Social Skills (M=37), Functional Communication (M=39), and overall Adaptive Skills (M=39). DSD scores were in the at-risk (T>60<70) range for 2 out of 8 cases and clinically significant (T>70) for 5 out of 8 cases.
The AUI was clinically significant for 2 out of the 3 cases within the age range for reporting AUI data.
Conclusions:
In this preliminary sample of DHH children with a confirmed diagnosis of ASD by comprehensive specialized interdisciplinary clinical evaluations, parent ratings on the BASC-3 were consistent with what is known about BASC-3 profiles in hearing children diagnosed with ASD. Our findings suggest it may be helpful to review the DSD, AUI, clinical scales, and adaptive skills scales profiles when assessing DHH children at risk for ASD. Further research, including a larger sample size and assessment of language differences among participants, is necessary.
The integrity of chromatin in the spermatozoon is essential for reproductive outcome. The aim of this study was to evaluate the most effective and cost-effective method to reduce the percentage of spermatozoa with defects in chromatin decondensation for use in assisted reproductive technologies (ART) procedures. Sperm samples from 15 sub-fertile males were examined at CFA Naples to determine the sperm decondensation index (SDI), using the aniline blue test, before and after preparation, comparing density gradients with two different swim-up approaches. All three techniques led to a reduction in decondensed spermatozoa with no statistical difference (P > 0.05) between the control and the treated sperm. In contrast, we found a highly significant decrease in SDI (P < 0.01) after the two swim-up methods in all the samples, confirming the efficacy of these methods in lowering the percentage of chromatin compaction damage. There was no statistical difference between the two swim-up methods, however swim-up from the pellet led to improved count, motility and the percentage of normal condensed spermatozoa. We suggest that swim-up from the pellet be used in ART on sub-fertile males, both to reduce cell stress by multiple centrifugation and improve the recovery rate of mature spermatozoa.
Neurodegeneration with brain iron accumulation (NBIA) is a rare genetic disorder. Its clinical manifestations comprise a wide spectrum mainly movement disorders. Seizure as a clinical manifestation is known to occur in some NBIAs, but the exact prevalence of epilepsy in each individual disorder is not well elucidated. The aim of this review was to investigate the frequency of seizures in NBIA disorders as well as to determine the associated features of patients with seizures.
Method:
The electronic bibliographic databases PubMed, Scopus, Embase, and Google Scholar were systematically searched for all cases in any type of article from inception to December 16, 2019. All the reported cases of NBIA (with or without genetic confirmation) were identified. Case reports with an explicit diagnosis of any types of NBIA, which have reported occurrence (or absence) of any type of seizure or epilepsy, in the English language, were included. Seizure incidence rate, type, and age of onset were reported as frequencies and percentages.
Result:
1698 articles were identified and 51 were included in this review. Of 305 reported cases, 150 (49.2%) had seizures (phospholipase A2-associated neurodegeneration (PLAN) = 64 (50.8%), beta-propeller protein-associated neurodegeneration (BPAN) = 57 (72.1%), pantothenate kinase-associated neurodegeneration (PKAN) = 11 (23.4%), and others = 18 (very variable proportions)). The most frequent seizure type in NBIA patients was generalized tonic-clonic seizure with the mean age of seizure onset between 2 and 36 years. However, most of these papers had been published before the new classification of epilepsy became accessible. Affected patients were more likely to be females.
Conclusion:
Seizures are common in NBIA, particularly in PLAN and BPAN. In PKAN, the most common type of NBIA, around 10% of patients are affected by seizures. BPAN is the most possible NBIA accompanying seizure. Most of the findings regarding the seizure characteristics in the NBIAs are biased due to the huge missing data. Therefore, any conclusions should be made with caution and need further investigations.
Background: Dopamine Dysregulation Syndrome (DDS) is an adverse non-motor complication of dopamine replacement therapy in Parkinson’s Disease. The current literature on DDS is limited, and it remains underdiagnosed and challenging to manage. Methods: We performed a retrospective chart review and classified patients according to risk factors that have been identified in the literature, UPDRS scores, intervention and outcome. Univariate analyses were performed to quantify these characteristics. Results: Prior psychiatric illness was identified in 70% of patients, impulse control disorder in 89% and substance abuse in 3.7%. Interventions included reduction of dopamine therapy (88.9%), deep brain stimulation (DBS) of the subthalamic nucleus (STN, 48.1%) or globus pallidus interna (GPi, 7.4%), and levodopa-carbidopa intestinal gel (LCIG) infusion (11.1%). Baseline UPDRS IV before treatment and MDS III after treatment were not significant between intervention groups (p=0.09 and p=0.13 respectively). Overall 88.9% patients improved at follow up, with medication only (75%), STN DBS (100%), GPi DBS (100%) and LCIG (33%). Relapse rate was 18.2%, in the STN group only. Conclusions: Our results suggest that GPi DBS, in concurrence with dopaminergic medication reduction, is the most effective intervention. STN DBS might be also beneficial although the associated medications reduction causes DDS relapse in a subgroup of patients.
Infant neurodevelopment is a complex process which may be affected by different events during pregnancy, such as hypertensive disorders of pregnancy (HDP). We conducted a prospective cohort study to compare the prevalence of neurodevelopmental disorders in infants born to mothers with and without HDP at six months of age. Participants attended the Health Observatory of Instituto de Desarrollo e Investigaciones Pediátricas “Prof. Dr. Fernando E. Viteri” during 2018 and 2019. Infant neurodevelopment was assessed with the Bayley Scales of Infant and Toddler Development—Third Edition (Bayley-III). Data were analyzed using Chi-square, Student’s t-test and Mann–Whitney test. Of the 132 participating infants, 68 and 64 were born to mothers with and without HDP, respectively. At six months, the prevalence of risk of neurodevelopmental delay was significantly higher in infants born to mothers with than without HDP (27.9% vs. 9.4%; p = 0.008) (odds ratio, 3.71; 95% confidence interval, 1.30; 12.28). In conclusion, infants born to mothers with HDP had three times increased risk of neurodevelopmental delay at six months of age.
Essential tremor (ET) is a common movement disorder with ˜5% prevalence in individuals above the age of 65, but in rare cases, it arises during childhood. Growing evidence suggests the role of cerebellum in the disease mechanism. ET is highly heritable, however, poor replication of risk loci point to its significant heterogeneity. Thus, it is important to genetically investigate kindreds with a strong aggregation of ET.
Methods:
We conducted a clinical and whole-genome investigation of a large Caucasian Canadian family, in which six out of eight patients are affected by childhood-onset ET in four consecutive generations. Eight family members were available for study, including three patients affected by ET. Whole-genome sequencing (WGS) was conducted for the four most informative individuals, followed by Sanger sequencing in the entire kindred.
Results:
We searched for rare variants absent in the eldest unaffected individual, but present in the patients (two siblings and their third-degree relative). Our stringent whole-genome filtering approach revealed a rare heterozygous p. Arg90Gln substitution in TCP10L (rs151233771) in all three investigated patients. Sanger sequencing confirmed the p. Arg90Gln variant and revealed its absence in the rest of the family members.
Conclusions:
Whole-genome data of the family with ET resulted in a single candidate gene mapped to 21q22.11 locus (TCP10L) with the highest brain expression in cerebellum. Our study encourages future replication studies to validate the genetic link between TCP10L and ET, and suggests the p. Arg90Gln variant for functional investigation.
Levodopa-carbidopa intestinal gel infusion (LCIG) is an established therapy for advanced Parkinson disease (PD), resulting in a significant improvement of quality of life. With increased LCIG adoption worldwide, potential complications due to abnormal vitamin absorption or metabolism have been reported in these patients. Neurologists are unfamiliar with vitamins physiology and pathophysiological mechanisms in case of their deficiency. Unfortunately, clinical and laboratory guidelines related to vitamin monitoring and supplementation in the context of treatment with LCIG are not available. We herein summarize the current knowledge on three vitamins that are reduced with LCIG therapy reporting on their physiology, laboratory testing, and clinical impact of their deficiency/excess. In addition, we proposed an opinion-based recommendation for clinicians treating LCIG patients. Patients and caregivers should be informed about the risk of vitamin deficiency. Vitamin B12, homocysteine, and methylmalonic acid (MMA) should be tested before starting LCIG, six months after and once/year thereafter. Vitamin B6 and folate testing is not universally available but it should be considered if homocysteine is elevated but MMA and/or total vitamin B12 are normal. Prophylaxis of vitamin deficiency should be started as soon as LCIG is implemented, possibly even before. Dietary recommendations are enough in most patients although a subgroup of patients is at higher risk and should receive Vitamin B12 regularly and cycles of B6. Finally, once diagnosed a vitamin deficiency should be readily treated and accompanied by clinical and laboratory monitoring. Resistant cases should receive non-oral routes of administration and possibly discontinue LCIG, even temporarily.