Unveiling the Uncommon: A Unique Case of ALPS-like Syndrome Complicated by Plasma Cell Disorder.

Multiple myeloma is a rare disease in pediatrics, where about 30 cases are described under 15 years old. It is even rarer when atypical multiple myeloma occurs in the context of autoimmunity. This case describes a 9-year-old female with autoimmune lymphoproliferative-like disease and combined immune deficiency that developed acute kidney failure with monoclonal peak associated with RAC2 and TNFRSF9 variants. An adapted protocol from the backbone adult multiple myeloma standard of care with the addition of an allogeneic hematopoietic stem cell transplant was used. The patient, now nearly a year posttransplant, shows 100% chimerism with no sign of relapse.

Safety of Direct Drug Provocation for the Evaluation of Penicillin Allergy in Low-Risk Adults.

BACKGROUND: About 10% of patients have a penicillin allergy label, but less than 5% of them are actually allergic. Unnecessary penicillin avoidance is associated with serious medical consequences. Given the growing number of these labels, it is imperative that our diagnostic strategy for penicillin allergy be as efficient as possible. The validity of traditionally used skin tests (STs) has been questioned, whereas drug provocation testing (DPT), the criterion standard, without previous ST appears very safe in most cases. OBJECTIVE: To evaluate the safety of direct DPT without consideration for ST results and the validity of ST in the diagnosis of penicillin allergy. METHODS: In this prospective cohort study without a control group, we recruited patients consulting an allergist for penicillin allergy. Patients underwent ST followed by DPT regardless of ST results. Patients with anaphylaxis to penicillin within the past 5 years or a severe delayed reaction were excluded, as were those with significant cardiorespiratory comorbidity. RESULTS: None of the 1002 recruited patients had a serious reaction to DPT. Ten (1.0%) had a mild immediate reaction, of whom only 1 (0.1%) was considered likely IgE-mediated. The positive and negative predictive values of ST for an immediate reaction were 3.6% and 99.1%, respectively. CONCLUSIONS: In a low-risk adult population reporting penicillin allergy, ST has very poor positive predictive value. Direct DPT without ST is safe and appears to be an ideal diagnostic strategy to remove penicillin allergy labels that could be implemented in first-line practice.

Parkinson's disease CA2-CA3 hippocampal atrophy is accompanied by increased cholinergic innervation in patients with normal cognition but not in patients with mild cognitive impairment.

Although brain cholinergic denervation has been largely associated with cognitive decline in patients with Parkinson's disease (PD), new evidence suggests that cholinergic upregulation occurs in the hippocampus of PD patients without cognitive deficits. The specific hippocampal sectors and potential mechanisms of this cholinergic compensatory process have been further studied here, using MRI volumetry and morphometry coupled with molecular imaging using the PET radiotracer [18F]-Fluoroethoxybenzovesamicol ([18F]-FEOBV). Following a thorough screening procedure, 18 participants were selected and evenly distributed in three groups, including cognitively normal PD patients (PD-CN), PD patients with mild cognitive impairment (PD-MCI), and healthy volunteers (HV). Participants underwent a detailed neuropsychological assessment, structural MRI, and PET imaging with [18F]-FEOBV. Basal forebrain Ch1-Ch2 volumes were measured using stereotaxic mapping. Hippocampal subfields were automatically defined using the MAGeT-Brain segmentation algorithm. Cholinergic innervation density was quantified using [18F]-FEOBV uptake. Compared with HV, both PD-CN and PD-MCI displayed significantly reduced volumes in CA2-CA3 bilaterally. We found no other hippocampal subfield nor Ch1-Ch2 volume differences between the three groups. PET imaging revealed higher [18F]-FEOBV uptake in CA2-CA3 of the PD-CN compared with HV or PD-MCI. A positive correlation was observed between cognitive performances and [18F]-FEOBV uptake in the right CA2-CA3 subfield. Reduced volume, together with increased [18F]-FEOBV uptake, were observed specifically in the CA2-CA3 hippocampal subfields. However, while the volume change was observed in both PD-CN and PD-MCI, increased [18F]-FEOBV uptake was present only in the PD-CN group. This suggests that a cholinergic compensatory process takes place in the atrophied CA2-CA3 hippocampal subfields and might underlie normal cognition in PD.

Hippocampal subfield associations with memory depend on stimulus modality and retrieval mode.

Hippocampal atrophy is a well-known feature of age-related memory decline, and hippocampal subfields may contribute differently to this decline. In this cross-sectional study, we investigated the associations between hippocampal subfield volumes and performance in free recall and recognition memory tasks in both verbal and visual modalities in older adults without dementia. We collected MRIs from 97 (41 males) right-handed participants aged over 60. We segmented the right and left hippocampi into (i) dentate gyrus and cornu ammonis 4 (DG/CA4); (ii) CA2 and CA3 (CA2/CA3); (iii) CA1; (iv) strata radiatum, lacunosum and moleculare; and (v) subiculum. Memory was assessed with verbal free recall and recognition tasks, as well as visual free recall and recognition tasks. Amyloid-ß and hippocampal tau positivity were assessed using [18F]AZD4694 and [18F]MK6240 PET tracers, respectively. The verbal free recall and verbal recognition performances were positively associated with CA1 and strata radiatum, lacunosum and moleculare volumes. The verbal free recall and visual free recall were positively correlated with the right DG/CA4. The visual free recall, but not verbal free recall, was also associated with the right CA2/CA3. The visual recognition was not significantly associated with any subfield volume. Hippocampal tau positivity, but not amyloid-ß positivity, was associated with reduced DG/CA4, CA2/CA3 and strata radiatum, lacunosum and moleculare volumes. Our results suggest that memory performances are linked to specific subfields. CA1 appears to contribute to the verbal modality, irrespective of the free recall or recognition mode of retrieval. In contrast, DG/CA4 seems to be involved in the free recall mode, irrespective of verbal or visual modalities. These results are concordant with the view that DG/CA4 plays a primary role in encoding a stimulus' distinctive attributes, and that CA2/CA3 could be instrumental in recollecting a visual memory from one of its fragments. Overall, we show that hippocampal subfield segmentation can be useful for detecting early volume changes and improve our understanding of the hippocampal subfields' roles in memory.

Mapping neurotransmitter systems to the structural and functional organization of the human neocortex.

Neurotransmitter receptors support the propagation of signals in the human brain. How receptor systems are situated within macro-scale neuroanatomy and how they shape emergent function remain poorly understood, and there exists no comprehensive atlas of receptors. Here we collate positron emission tomography data from more than 1,200 healthy individuals to construct a whole-brain three-dimensional normative atlas of 19 receptors and transporters across nine different neurotransmitter systems. We found that receptor profiles align with structural connectivity and mediate function, including neurophysiological oscillatory dynamics and resting-state hemodynamic functional connectivity. Using the Neurosynth cognitive atlas, we uncovered a topographic gradient of overlapping receptor distributions that separates extrinsic and intrinsic psychological processes. Finally, we found both expected and novel associations between receptor distributions and cortical abnormality patterns across 13 disorders. We replicated all findings in an independently collected autoradiography dataset. This work demonstrates how chemoarchitecture shapes brain structure and function, providing a new direction for studying multi-scale brain organization.

Cholinergic system changes in Parkinson's disease: emerging therapeutic approaches.

In patients with Parkinson's disease, heterogeneous cholinergic system changes can occur in different brain regions. These changes correlate with a range of clinical features, both motor and non-motor, that are refractory to dopaminergic therapy, and can be conceptualised within a systems-level framework in which nodal deficits can produce circuit dysfunctions. The topographies of cholinergic changes overlap with neural circuitries involved in sleep and cognitive, motor, visuo-auditory perceptual, and autonomic functions. Cholinergic deficits within cognition network hubs predict cognitive deficits better than do total brain cholinergic changes. Postural instability and gait difficulties are associated with cholinergic system changes in thalamic, caudate, limbic, neocortical, and cerebellar nodes. Cholinergic system deficits can involve also peripheral organs. Hypercholinergic activity of mesopontine cholinergic neurons in people with isolated rapid eye movement (REM) sleep behaviour disorder, as well as in the hippocampi of cognitively normal patients with Parkinson's disease, suggests early compensation during the prodromal and early stages of Parkinson's disease. Novel pharmacological and neurostimulation approaches could target the cholinergic system to treat motor and non-motor features of Parkinson's disease.

Tiotropium bromide as adjunct therapy in children with asthma: a clinical experience.

BACKGROUND: The Global Initiative for Asthma has only recently added tiotropium bromide as adjunct controller therapy in severe asthma (Step 4 or 5) in adults (2015) and children (2019). Although not yet approved for pediatric use by Health Canada, it has been occasionally offered by asthma specialists as a therapeutic trial in children with troublesome asthma or treatment for adverse effects. The objective of this study was to describe the indications and real-life clinical experience in initiating tiotropium in children with asthma. METHODS: We designed a retrospective mixed-method case series study of children aged 1-17 years who initiated tiotropium in our tertiary-care centre between 2013 and 2020. Clinical information was extracted from electronic medical records and tiotropium dispensing, from drug claims. Parents/children and physicians independently completed a questionnaire about treatment goals, perceived efficacy, safety, satisfaction, and lessons learned. RESULTS: The 34 (11 females; 23 males) children had a median (range) age of 9.1 (1.4-17.8) years. Children were primarily on Step 4 (85%) or 5 (6%) prior to tiotropium initiation, yet most (84%) did not increase their treatment step after tiotropium initiation. The physicians' treatment goals were to improve asthma control, alleviate adverse effects of current therapy, and/or improve lung function. The most improved symptoms were coughing/moist cough, difficulty breathing, whistling breath, and bronchial secretions/mucus. Although most parents and physicians reported a significant benefit with tiotropium bromide, physicians particularly remarked, as their "lesson learned', on the improvement in chronic symptoms in asthmatic children, particularly those with prominent moist cough and in lung function, in those with seemingly none (or incompletely) reversible obstruction as well as the ability to decrease the ICS and/or LABA dose to lessen adverse effects. A few physicians raised caution on the risk of lower adherence with an additional inhaler. CONCLUSION: In children with severe asthma on Step 4 or 5, tiotropium bromide was primarily used as substitute, rather than additional, adjunct therapy to improve asthma control, alleviate adverse effects, and/or to improve lung function. The latter two indications, combined with its perceived effectiveness in children with prominent moist cough, also suggest additional indications of tiotropium to be formally explored.

Normal cognition in Parkinson's disease may involve hippocampal cholinergic compensation: An exploratory PET imaging study with [18F]-FEOBV.

BACKGROUND: Severe cholinergic degeneration is known to occur in Parkinson's disease (PD) and is thought to play a primary role in the cognitive decline associated with this disease. Although cholinergic losses occur in all patients with PD, cognitive performance remains normal for many of them, suggesting compensatory mechanisms in those. OBJECTIVES: This exploratory study aimed at verifying if normal cognition in PD may involve distinctive features of the brain cholinergic systems. METHODS: Following extensive neuropsychological screening in 25 patients with PD, 12 were selected and evenly distributed between a cognitively normal (PD-CN) group, and a mild cognitive impairment (PD-MCI) group. Each group was compared with matched healthy volunteers (HV) on standardized cognitive scales (MoCA, PDCRS), and PET imaging with [18F]-FEOBV, a sensitive measurement of brain cholinergic innervation density. RESULTS: [18F]-FEOBV uptake reductions were observed in PD-CN as well as in PD-MCI, with the lowest values located in the posterior cortical areas. However, in PD-CN but not in PD-MCI, there was a significant and bilateral increase of [18F]-FEOBV uptake, exclusively located in the hippocampus. Significant correlations were observed between cognitive performance and hippocampal [18F]-FEOBV uptake. CONCLUSION: These findings suggest a compensatory upregulation of the hippocampal cholinergic innervation in PD-CN, which might underly normal cognitive performances in spite of cortical cholinergic denervation in other regions.

Molecular Imaging of the Cholinergic System in Alzheimer and Lewy Body Dementias: Expanding Views.

PURPOSE OF REVIEW: Brain cholinergic denervation is a major feature of Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). We reviewed the topography assessed by a cholinergic molecular imaging study in these two major types of dementia. A small meta-analysis directly comparing vesicular acetylcholine transporter (VAChT) PET scans of AD vs. DLB patients is presented. RECENT FINDINGS: VAChT PET studies showed evidence of extensive cortical cholinergic denervation in both forms of dementia, while multiple subcortical structures were also in DLB. Novel analysis revealed evidence of metathalamic denervation in AD, and epithalamus, premotor/sensorimotor cortical, and striatal losses in DLB. Topographically distinct cortical and subcortical cholinergic lesions can distinguish AD and DLB, and new structures have been highlighted here. Differential vulnerability of specific cholinergic projections is likely associated with specific clinical features of these disorders. Improved understanding of the mechanisms and roles of cholinergic neurotransmission in regions with cholinergic deficits may lead to symptomatic therapies.

FEOBV-PET to quantify cortical cholinergic denervation in AD: Relationship to basal forebrain volumetry.

BACKGROUND AND PURPOSE: Fluorine-18-fluoroethoxybenzovesamicol([18 F]-FEOBV) is a PET radiotracer previously used in neurodegenerative diseases to quantify brain cholinergic denervation. The current exploratory study aimed at verifying the reliability of such an approach in Alzheimer's disease (AD) by demonstrating its concordance with MRI volumetry of the cholinergic basal forebrain (ChBF). METHODS: The sample included 12 participants evenly divided between healthy volunteers and patients with AD. All participants underwent MRI ChBF volumetry and PET imaging with [18 F]-FEOBV. Comparisons were made between the two groups, and partial correlations were performed in the AD patients between [18 F]-FEOBV uptake in specific cortical regions of interest (ROIs) and volumetry of the corresponding ChBF subareas, which include the nucleus basalis of Meynert (Ch4), and the medial septum/vertical limb of the diagonal band of Broca (Ch1/2). RESULTS: Patients with AD showed both lower ChBF-Ch4 volumetric values and lower [18 F]-FEOBV cortical uptake than healthy volunteers. Volumes of the Ch4 subdivision were significantly correlated with the [18 F]-FEOBV uptake values observed in the relevant ROIs. Volumes of the Ch1/2, which remains relatively unaffected in AD, did not correlate with [18 F]-FEOBV uptake in the hippocampus, nor in any cortical area. CONCLUSION: These results suggest that cortical cholinergic denervation as measured with [18 F]-FEOBV PET is proportional to ChBF atrophy measured by MRI-based volumetry, further supporting the reliability and validity of [18 F]-FEOBV PET to quantify cholinergic degeneration in AD.

Cognitive dysfunction after out-of-hospital cardiac arrest: Rate of impairment and clinical predictors.

BACKGROUND: The purpose of this study was to evaluate the rate and domains of cognitive impairment in out-of-hospital cardiac arrest (OHCA) survivors, as compared to patients who experienced a myocardial infarction (MI), and to explore mechanisms and predictors of this impairment. METHODS AND RESULTS: OHCA survivors with "good" neurological recovery (i.e., Cerebral Performance Categories Scale ≤ 2) (n = 79), as well as a control group of MI patients (n = 69), underwent a comprehensive neuropsychological assessment. Forty-three percent of OHCA survivors were cognitively impaired (in the lowest decile on a global measure of cognitive functioning). Rates of impairment were approximately six times higher in the OHCA group than the MI group. Attention, memory, language and executive function were affected. Downtime was a significant predictor of cognitive impairment; the interaction between downtime and immediate intervention was significant such that, at short downtimes, receiving cardiopulmonary resuscitation (CPR) or defibrillation within 1 min of collapse predicted less cognitive impairment. CONCLUSIONS: OHCA survivors - even those with seemingly good neurological recovery - are at risk for cognitive impairment. Cognitive rehabilitation may be an important consideration post-OHCA.

Social support, neurocognition, and posttraumatic stress disorder: Findings from the Canadian Longitudinal Study on Aging.

OBJECTIVE: Most research investigating neurocognitive changes in participants with PTSD has focused on young adults. Numerous studies have recognized the crucial role of social support in diminishing the likelihood of developing PTSD. The current study evaluates the cognitive performance of middle-aged and older adults with symptoms of PTSD, and examines if perceived social support can act as a cognitive reserve factor. METHOD: The study was conducted using data from the Canadian Longitudinal Study on Aging, a nationwide study on health and aging. The current study included 1,096 participants in the PTSD group and 22,158 participants in the comparison group, all between the ages of 45 and 85. Participants completed the MOS (Medical Outcomes Study) Social Support Survey as well as neuropsychological tests in the domains of executive functioning, declarative memory, and prospective memory. RESULTS: The PTSD group had worse performance in the domains of executive functioning and prospective memory than the comparison group. Furthermore, when examining global cognitive impairments (impairment was defined as scoring 1.5 or more standard deviations below age and education adjusted comparison group), the PTSD group demonstrated greater impairment rates than the comparison group on two or more tests. Moderation analyses revealed that greater social support was associated with better executive functioning for the comparison group, although this was not found to be true for the PTSD group. CONCLUSION: The PTSD group experienced greater cognitive deficits compared to the comparison group. Higher levels of perceived social support were associated with better performance on neurocognitive measures for the comparison group. However, social support did not appear to moderate this relationship for the PTSD group.

Social Support Buffers Against Cognitive Decline in Single Mild Traumatic Brain Injury With Loss of Consciousness: Results From the Canadian Longitudinal Study on Aging.

OBJECTIVES: We investigated rates of cognitive decline at 3-year follow-up from initial examination in people reporting mild traumatic brain injury (mTBI) with loss of consciousness (LOC) more than a year prior to initial examination. We examined the role of social support as predictor of preserved cognitive function in this sample. METHOD: Analyses were conducted on 440 participants who had self-reported LOC of <1 min, 350 with LOC of 1-20 min, and 10,712 healthy controls, taken from the Canadian Longitudinal Study on Aging (CLSA), a nationwide study on health and aging. RESULTS: People who reported at baseline that they had experienced mTBI with LOC of 1-20 min more than a year prior were 60% more likely to have experienced global cognitive decline than controls at three-year follow-up. Cognitive decline was most apparent on measures of executive functioning. Logistic regression identified increased social support as predictors of relatively preserved cognitive function. DISCUSSION: mTBI with longer time spent unconscious (i.e., LOC 1-20 min) is associated with greater cognitive decline years after the head injury. Perceived social support, particularly emotional support, may help buffer against this cognitive decline.

Risk of adrenal insufficiency following intra-articular or periarticular corticosteroid injections among children with chronic arthritis.

Objectives Intra-articular and/or periarticular corticosteroid injection (IACI) is a common procedure in pediatric rheumatology. Despite many adult studies demonstrating a significant risk of adrenal insufficiency (AI) following the procedure, very little evidence is available in the pediatric literature regarding this risk. The main goal of this study is to evaluate the prevalence of AI in children with chronic arthritis following IACI. Methods This is a retrospective study including children aged 0-18 years who had an IACI from June 2017 to July 2019. An 8:00 morning cortisol (8MC) sample was drawn around two weeks after the injection, and an ACTH 1mcg stimulation test was performed if morning cortisol level was low. AI was defined as an 8MC under 50 nmol/L or an abnormal ACTH stimulation test. Risks factors for AI and its duration were assessed. Results Sixty patients were included in this study. AI prevalence was 30% with 18 of 60 affected patients. The corticosteroid dose injected was statistically associated with the development of AI. Median duration of AI was 181 days for the nine patients who were followed up until resolution of AI. Four patients developed symptoms of AI, namely fatigue (2 of 4), nausea (2 of 4) and abdominal pain (3 of 4). None were hospitalized or died. Conclusions In this cohort of children with chronic arthritis who had an IACI, we found a high prevalence of AI. Monitoring and counseling of such complication is warranted until further evidence is available.

Long-term cognitive impairment following single mild traumatic brain injury with loss of consciousness: Findings from the Canadian Longitudinal Study on Aging.

Objective: We examined the extent to which loss of consciousness (LOC) following mild traumatic brain injury (mTBI) may be associated with impairments in executive functions and declarative memory more than a year after brain injury.Method: Analyses were run on 548 participants who had self-reported LOC of <1 min, 441 with LOC of 1-20 min, and 13,609 no brain injury comparison participants, taken from the Canadian Longitudinal Study on Aging (CLSA), a nationwide study on health and aging.Results: Those that had mTBI with LOC of 1-20 min were more likely than no head injury comparisons to be impaired on measures of executive functioning and declarative memory. Impairments were evident when examining for single- and two-test impairment rates on measures of executive functioning and declarative memory.Conclusions: A subset of people that had reported a single mTBI with LOC more than 12 months ago may experience impairments in executive functioning and declarative memory, particularly those who spent more time unconscious.