Interhypothalamic adhesion and multiple cerebral abnormalities in a 2-year-old boy.

International audienceInterhypothalamic adhesion (IHA) is a band of tissue spanning the anterior recess of the third ventricle, linear in the transverse and frontal planes. Recently described, in 2008 [1] in a patient with a Chiari type II malformation, IHA is commonly associated with multiple congenital anomalies [2] particularly midline disorders but can also be isolated. IHA is related with hypothalamo-pituitary dysfunctions and seizures in most of patient, but asymptomatic patients have been reported [3]. Here, we present a case of IHA associated with corpus callosum agenesis (CCA)

AP4 deficiency: A novel form of neurodegeneration with brain iron accumulation?

OBJECTIVE: To describe the clinico-radiological phenotype of 3 patients harboring a homozygous novel AP4M1 pathogenic mutation. METHODS: The 3 patients from an inbred family who exhibited early-onset developmental delay, tetraparesis, juvenile motor function deterioration, and intellectual deficiency were investigated by magnetic brain imaging using T1-weighted, T2-weighted, T2*-weighted, fluid-attenuated inversion recovery, susceptibility weighted imaging (SWI) sequences. Whole-exome sequencing was performed on the 3 patients. RESULTS: In the 3 patients, brain imaging identified the same pattern of bilateral SWI hyposignal of the globus pallidus, concordant with iron accumulation. A novel homozygous nonsense mutation was identified in AP4M1, segregating with the disease and leading to truncation of half of the adap domain of the protein. CONCLUSIONS: Our results suggest that AP4M1 represents a new candidate gene that should be considered in the neurodegeneration with brain iron accumulation (NBIA) spectrum of disorders and highlight the intersections between hereditary spastic paraplegia and NBIA clinical presentations

Case Report: Cerebrovascular Events Associated With Bacterial and SARS-CoV-2 Infections in an Adolescent

International audienceNeurologic manifestations associated with Covid-19 are increasingly reported, especially stroke and acute cerebrovascular events. Beyond cardiovascular risk factors associated with age, some young adults without medical or cardiovascular history had stroke as a presenting feature of Covid-19. Suggested stroke mechanisms in this setting are inflammatory storm, subsequent hypercoagulability, and vasculitis. To date, a handful of pediatric stroke cases associated with Covid-19 have been reported, either with a cardioembolic mechanism or a focal cerebral arteriopathy. We report the case of an adolescent who presented with febrile meningism and stupor. Clinical, biological, and radiological features favored the diagnosis of Lemierre syndrome (LS), with Fusobacterium necrophorum infection (sphenoid sinusitis and meningitis) and intracranial vasculitis. The patient had concurrent SARS-CoV-2 infection. Despite medical and surgical antimicrobial treatment, stroke prevention, and venous thrombosis prevention, he presented with severe cerebrovascular complications. Venous thrombosis and stroke were observed, with an extension of intracranial vasculitis, and lead to death. As both F. necrophorum and SARS-CoV-2 enhance inflammation, coagulation, and activate endothelial cells, we discuss how this coinfection may have potentiated and aggravated the usual course of LS. The potentiation by SARS-CoV-2 of vascular and thrombotic effects of a bacterial infection may represent an underreported cerebrovascular injury mechanism in Covid-19 patients. These findings emphasize the variety of mechanisms underlying stroke in this disease. Moreover, in the setting of SARS-CoV-2 pandemic, we discuss in what extent sanitary measures, namely, lockdown and fear to attend medical facilities, may have delayed diagnosis and influenced outcomes. This case also emphasizes the role of clinical assessment and the limits of telemedicine for acute neurological condition diagnosis

Phenotypic diversity of brain MRI patterns in mitochondrial aminoacyl-tRNA synthetase mutations

International audienceBackground and purpose: Mitochondrial aminoacyl-tRNA synthetases-encoded by ARS2 genes-are evolutionarily conserved enzymes that catalyse the attachment of amino acids to their cognate tRNAs, ensuring the accuracy of the mitochondrial translation process. ARS2 gene mutations are associated with a wide range of clinical presentations affecting the CNS.Methods: Two senior neuroradiologists analysed brain MRI of 25 patients (age range: 3 d-25 yrs.; 11 males; 14 females) with biallelic pathogenic variants of 11 ARS2 genes in a retrospective study conducted between 2002 and 2019.Results: Though several combinations of brain MRI anomalies were highly suggestive of specific aetiologies (DARS2, EARS2, AARS2 and RARS2 mutations), our study detected no MRI pattern common to all patients. Stroke-like lesions were associated with pathogenic SARS2 and FARS2 variants. We also report early onset cerebellar atrophy and calcifications in AARS2 mutations, early white matter involvement in RARS2 mutations, and absent involvement of thalami in EARS2 mutations. Finally, our findings show that normal brain MRI results do not exclude the presence of ARS2 mutations: 5 patients with normal MRI images were carriers of pathogenic IARS2, YARS2, and FARS2 variants.Conclusion: Our study extends the spectrum of brain MRI anomalies associated with pathogenic ARS2 variants and suggests ARS2 mutations are largely underdiagnosed

Abnormal Spontaneous Blood Oxygenation Level Dependent Fluctuations in Children with Focal Cortical Dysplasias:Initial findings in surgically confirmed cases

Background  Focal cortical dysplasias (FCD) are a frequent cause of drug-resistant epilepsy in children but are often undetected on structural magnetic resonance imaging (MRI). We aimed to measure and validate the variation of resting state functional MRI (rs-fMRI) blood oxygenation level dependent (BOLD) metrics in surgically proven FCDs in children, to assess the potential yield for detecting and understanding these lesions. Methods  We prospectively included pediatric patients with surgically proven FCD with inconclusive structural MRI and healthy controls, who underwent a ten-minute rs-fMRI acquired at 3T. Rs-fMRI data was pre-processed and maps of values of regional homogeneity (ReHo), degree centrality (DC), amplitude of low frequency fluctuations (ALFF) and fractional ALFF (fALFF) were calculated. The variations of BOLD metrics within the to-be-resected areas were analyzed visually, and quantitatively using lateralization indices. BOLD metrics variations were also analyzed in fluorodeoxyglucose-positron emission tomography (FDG-PET) hypometabolic areas. Results  We included 7 patients (range: 3-15 years) and 6 aged-matched controls (range: 6-17 years). ReHo lateralization indices were positive in the to-be-resected areas in 4/7 patients, and in 6/7 patients in the additional PET hypometabolic areas. These indices were significantly higher compared to controls in 3/7 and 4/7 patients, respectively. Visual analysis revealed a good spatial correlation between high ReHo areas and MRI structural abnormalities (when present) or PET hypometabolic areas. No consistent variation was seen using DC, ALFF, or fALFF. Conclusion  Resting-state fMRI metrics, noticeably increase in ReHo, may have potential to help detect MRI-negative FCDs in combination with other morphological and functional techniques, used in clinical practice and epilepsy-surgery screening.</p

Radiogenomics of diffuse intrinsic pontine gliomas (DIPGs): correlation of histological and biological characteristics with multimodal MRI features

International audienceThe diffuse intrinsic pontine gliomas (DIPGs) are now defined by the type of histone H3 mutated at lysine 27. We aimed to correlate the multimodal MRI features of DIPGs, H3K27M mutant, with their histological and molecular characteristics

Severe Acute Flaccid Myelitis Associated With Enterovirus in Children: Two Phenotypes for Two Evolution Profiles?

International audienceAcute flaccid myelitis (AFM) is an acute paralysis syndrome defined by a specific inflammation of the anterior horn cells of the spinal cord. From 2014, worrying waves of life-threatening AFM consecutive to enterovirus infection (EV-D68 and EV-A71) have been reported. We describe 10 children displaying an AFM with an EV infection, the treatments performed and the 1 to 3-years follow-up. Two groups of patients were distinguished: 6 children (“polio-like group”) had severe motor disability whereas 4 other children (“brainstem group”) displayed severe brainstem weakness requiring ventilation support. Electrodiagnostic studies (n = 8) support the presence of a motor neuronopathy associated to myelitis. The best prognosis factor seems to be the motor recovery after the first 4 weeks of the disease

Arterial spin labeling brain MRI study to evaluate the impact of deafness on cerebral perfusion in 79 children before cochlear implantation

International audienceAge at implantation is considered to be a major factor, influencing outcomes after pediatric cochlear implantation. In the absence of acoustic input, it has been proposed that cross-modal reorganization can be detrimental for adaptation to the new electrical input provided by a cochlear implant. Here, through a retrospective study, we aimed to investigate differences in cerebral blood flow (CBF) at rest prior to implantation in children with congenital deafness compared to normally hearing children. In addition, we looked at the putative link between pre-operative rest-CBF and the oral intelligibility scores at 12 months post-implantation. Finally, we observed the evolution of perfusion with age, within brain areas showing abnormal rest-CBF associated to deafness, in deaf children and in normally hearing children. In children older than 5 years old, results showed a significant bilateral hypoperfusion in temporal regions in deaf children, particularly in Heschl's gyrus, and a significant hyperperfusion of occipital regions. Furthermore, in children older than 5 years old, whole brain voxel-by-voxel correlation analysis between pre-operative rest-CBF and oral intelligibility scores at 12 months post-implantation, showed significant negative correlation localized in the occipital regions: children who performed worse in the speech perception test one year after implantation were those presenting higher preoperative CBF values in these occipital regions. Finally, when comparing mean relative perfusion (extracted from the temporal regions found abnormal on whole-brain voxel-based analysis) across ages in patients and controls, we observed that the temporal perfusion evolution was significantly different in deaf children than in normally hearing children. Indeed, while temporal perfusion increased with age in normally hearing children, it remained stable in deaf children. We showed a critical period around 4 years old, where in the context of auditory deprivation, there is a lack of synaptic activity in auditory regions. These results support the benefits of early cochlear implantation to maximize the effectiveness of auditory rehabilitation and to avoid cross-modal reorganization

Heterogeneity of PNPT1 neuroimaging: Mitochondriopathy, interferonopathy or both?

© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.Background: Biallelic variants in PNPT1 cause a mitochondrial disease of variable severity. PNPT1 (polynucleotide phosphorylase) is a mitochondrial protein involved in RNA processing where it has a dual role in the import of small RNAs into mitochondria and in preventing the formation and release of mitochondrial double-stranded RNA into the cytoplasm. This, in turn, prevents the activation of type I interferon response. Detailed neuroimaging findings in PNPT1-related disease are lacking with only a few patients reported with basal ganglia lesions (Leigh syndrome) or non-specific signs. Objective and methods: To document neuroimaging data in six patients with PNPT1 highlighting novel findings. Results: Two patients exhibited striatal lesions compatible with Leigh syndrome; one patient exhibited leukoencephalopathy and one patient had a normal brain MRI. Interestingly, two unrelated patients exhibited cystic leukoencephalopathy resembling RNASET2-deficient patients, patients with Aicardi-Goutières syndrome (AGS) or congenital CMV infection. Conclusion: We suggest that similar to RNASET2, PNPT1 be searched for in the setting of cystic leukoencephalopathy. These findings are in line with activation of type I interferon response observed in AGS, PNPT1 and RNASET2 deficiencies, suggesting a common pathophysiological pathway and linking mitochondrial diseases, interferonopathies and immune dysregulations