Infeccions per Enterovirus i Parechovirus que produeixen patologies neurològiques i sistèmiques en el pacient pediàtric. Vigilància epidemiològica i estudi de biomarcadors de gravetat

[cat] INTRODUCCIÓ: Aquesta Tesi doctoral s’inscriu en el marc de dos projectes FIS consecutius que han dut a terme una activitat de vigilància epidemiològica de les infeccions per Enterovirus (EV) i Parechovirus (HPeV) a Espanya. Al març de 2016 a Catalunya es van reportar una sèrie de pacients pediàtrics amb patologia neurològica aguda associada a infecció per EV. A Espanya, mai no s’havia descrit un brot d’infecció per EV amb aquestes característiques clíniques. OBJECTIUS: Descriure les característiques dels pacients pediàtrics ingressats per infeccions per EV amb manifestacions neurològiques en el nostre medi durant la temporada epidèmica de l’any 2016. Demostrar la neuroinfecció en els pacients afectes pel brot d’encefalitis de tronc per EV mitjançant noves tècniques de biologia molecular per a la detecció de múltiples patògens. Descriure quins són els valors de neopterina en LCR en els pacients amb encefalitis de tronc per EV. Descriure les característiques dels pacients pediàtrics ingressats per infeccions per HPeV amb manifestacions neurològiques i sistèmiques en el nostre medi durant el període 2015-2018. PACIENTS I MÈTODES: Es dissenyen tres estudis amb recollida prospectiva de dades clíniques, analítiques, radiològiques i microbiològiques en els quals s’inclouen pacients pediàtrics amb manifestacions neurològiques, detecció d’EV en alguna mostra i absència d’una altra etiologia plausible, amb diferents períodes d’inclusió a partir d’abril de 2016. El quart estudi, fruit de la vigilància epidemiològica de les infeccions per HPeV entre 2015 i 2018, és un article a propòsit de dos casos. Els quatre estudis es realitzen en un hospital pediàtric de tercer nivell (Hospital Sant Joan de Déu, Universitat de Barcelona) i els resultats es presenten a la memòria d’aquesta tesi. S’efectuen els procediments estadístics pertinents per al tractament de dades. RESULTATS: Durant l’any 2016 a Catalunya, la circulació de l’EV-A71 va condicionar l’aparició d’un brot d’encefalitis de tronc en pacients pediàtrics. La soca predominant corresponia a una nova soca recombinant C1 detectada per primer cop a Alemanya l’any 2015. L’únic genotip d’EV aïllat en els pacients amb encefalitis de tronc o encefalomielitis va ser l’EV-A71. La PCR niada múltiple va permetre demostrar la presència d’EV en el LCR d’alguns pacients amb encefalitis de tronc, reforçant la hipòtesi de la neuroinfecció. No es va trobar cap coinfecció bacteriana ni viral amb rellevància clínica. El perfil del pacient afecte d’encefalitis de tronc per EV-A71 era de lactant o pre-escolar. Destaca la baixa proporció de manifestacions mucocutànies. La majoria van presentar encefalitis de tronc i només una minoria encefalomielitis amb fallada cardiopulmonar. L’edat menor de 12 mesos i els valors més elevats de leucòcits i procalcitonina en plasma es van associar amb fallada cardiopulmonar. La presència d’encefalomielitis es va associar amb la persistència de seqüeles als 30 dies. Els nivells de neopterina en LCR estan elevats en la majoria de pacients amb encefalitis de tronc per EV. Nivells més elevats de neopterina en LCR es van correlacionar amb la presència de lesions i lesions extenses a la RM. Durant el període 2015-2018 es van identificar 4 pacients amb infecció per HPeV-3; en dos lactants es va detectar hiperferritinèmia extrema en el context d’una infecció de curs benigne.[eng] INTRODUCTION: This Doctoral Thesis is part of two consecutive FIS projects that have carried out an epidemiological surveillance of Enterovirus (EV) and Parechovirus (HPeV) infections in Spain. An outbreak of EV infection affecting children with acute neurological manifestations was reported in Catalonia in March 2016. OBJECTIVES: To describe the characteristics of paediatric patients hospitalized due to EV infection with neurological manifestations in 2016. To demonstrate neuroinfection in patients with EV brainstem encephalitis using new molecular biology techniques for multiple pathogen detection. To describe the values of CSF neopterin in patients with EV brainstem encephalitis. To describe the characteristics of paediatric patients hospitalized due to HPeV infection between 2015-2018. PATIENTS AND METHODS: In the first three studies, patients with neurological manifestations were included if EV infection was detected in any sample and no other cause was identified. Data were prospectively collected. The three studies had different inclusion periods, beginning in April 2016. The fourth study is a case report including two cases with HPeV-3 infection. The four studies were carried out in a tertiary paediatric hospital (Hospital Sant Joan de Déu, University of Barcelona). Appropriate statistical analysis was carried out to analyse the data. RESULTS: An outbreak of brainstem encephalitis associated with EV-A71 infection affecting paediatric patients occurred in Catalonia in 2016. Most of the detected EV-A71 strains were subgenogroup C1, wich formed a subclade together with the variant strain detected in Germany in 2015. EV was detected in CSF samples of some patients with brainstem encephalitis using multiple nested PCR, reinforcing the hypothesis of neuroinfection. No relevant bacterial or viral coinfections were found. Age younger than 12 months, higher plasma white blood cell counts and higher plasma procalcitonin levels were related to a more severe disease. The presence of encephalomyelitis was associated with the persistence of sequelae at day 30. CSF neopterin levels are elevated in the majority of patients with EV brainstem encephalitis. Higher CSF neopterin levels correlated with the presence of lesions and extensive lesions on MRI. Four patients with HPeV-3 infection were identified between 2015-2018; in two infants with a self-limited disease, extreme hyperferritinemia was found

Diagnostic strategies in patients with undiagnosed and rare diseases

Rare diseases are life-threatening or chronically debilitating conditions affecting millions of people worldwide. In many instances, the patients experience a delay in their diagnosis or remain undiagnosed despite extensive investigations carried out by specialists. There are several explanations to account for this phenomenon including the socioeconomic context and the lack of an established consensus for diagnostic testing. Nonetheless, the widespread use of genetic and genomic tests in the past decades has had a major impact on clinical reasoning paradigms, and new troves of data are constantly being generated and analyzed. This requires constantly updating tools to match the discovery rate and allow reanalysis. In this review, we summarize the latest international recommendations and guidelines to address the problem of diagnostic deficit as well as present the current diagnostic workflows. Increasing access to exome and genome sequencing technologies and biological validation, gaining insight into the interpretation of multi-omics datasets, and fostering data sharing would reduce the long diagnostic odyssey and diagnostic gap

Early-onset severe spinocerebellar ataxia 42 with neurodevelopmental deficits (SCA42ND): Case report, pharmacological trial, and literature review

Early-onset severe spinocerebellar ataxia 42 with neurodevelopmental deficits (SCA42ND, MIM#604065) is an ultrarare autosomal dominant syndrome related to de novo CACNA1G gain-of-function pathogenic variants. All patients with SCA42ND show cerebellar atrophy and/or hypoplasia on neuroimaging and share common features such as dysmorphic features, global developmental delay, and axial hypotonia, all manifesting within the first year of life. To date, only 10 patients with SCA42ND have been reported with functionally confirmed gain-of-function variants, bearing either of two recurrent pathogenic variants. We describe a girl with congenital ataxia, without epilepsy, and a de novo p.Ala961Thr pathogenic variant in CACNA1G. We review the published subjects with the aim of better characterizing the dysmorphic features that may be crucial for clinical recognition of SCA42ND. Cerebellar atrophy, together with digital anomalies, particularly broad thumbs and/or halluces, should lead to clinical suspicion of this disease. We describe the first pharmacological attempt to treat a patient with SCA42ND using zonisamide, an antiepileptic drug with T-type channel blocker activity, in an off-label indication using an itemized study protocol. No efficacy was observed at the dose tested. However, without pharmacological treatment, she showed a positive evolution in neurodevelopment during the follow-up.This work was supported by a National Grant PI17/00101 from the National R&D&I Plan, cofinanced by the Instituto de Salud Carlos III (Subdirectorate-General for Evaluation and Promotion of Health Research) and FEDER (European Regional Development Fund). M.S. is supported by the Generalitat de Catalunya (PERIS SLT008/18/00194). J.M.F-F. is supported by the Spanish Ministry of Science and Innovation, the State Research Agency (AEI, Agencia Estatal de Investigación), and FEDER Funds (Fondo Europeo de Desarrollo Regional): Grants RTI2018-094809-B-I00, and CEX2018-000792-M through the “María de Maeztu” Programme for Units of Excellence in R&D to “Departament de Ciències Experimentals i de la Salut”

CACNA1A mutations causing early onset ataxia: profiling clinical, dysmorphic and structural-functional findings

The CACNA1A gene encodes the pore-forming α1A subunit of the voltage-gated CaV2.1 Ca2+ channel, essential in neurotransmission, especially in Purkinje cells. Mutations in CACNA1A result in great clinical heterogeneity with progressive symptoms, paroxysmal events or both. During infancy, clinical and neuroimaging findings may be unspecific, and no dysmorphic features have been reported. We present the clinical, radiological and evolutionary features of three patients with congenital ataxia, one of them carrying a new variant. We report the structural localization of variants and their expected functional consequences. There was an improvement in cerebellar syndrome over time despite a cerebellar atrophy progression, inconsistent response to acetazolamide and positive response to methylphenidate. The patients shared distinctive facial gestalt: oval face, prominent forehead, hypertelorism, downslanting palpebral fissures and narrow nasal bridge. The two α1A affected residues are fully conserved throughout evolution and among the whole human CaV channel family. They contribute to the channel pore and the voltage sensor segment. According to structural data analysis and available functional characterization, they are expected to exert gain- (F1394L) and loss-of-function (R1664Q/R1669Q) effect, respectively. Among the CACNA1A-related phenotypes, our results suggest that non-progressive congenital ataxia is associated with developmental delay and dysmorphic features, constituting a recognizable syndromic neurodevelopmental disorder.This work was funded by the Spanish Ministry of Health, Consumer Affairs and Social Welfare, the Spanish Ministry of Science and Innovation, the State Research Agency (AEI, Agencia Estatal de Investigación), and FEDER Funds (Fondo Europeo de Desarrollo Regional): Grants RTI2018-094809-B-I00 to J.M.F.F. and CEX2018-000792-M through the “María de Maeztu” Programme for Units of Excellence in R&D to “Departament de Ciències Experimentals i de la Salut”. M.S. is supported by the Generalitat de Catalunya (PERIS SLT008/18/00194) and National Grant PI17/00101 from the National R&D&I Plan, cofinanced by the Instituto de Salud Carlos III (Subdirectorate-General for Evaluation and Promotion of Health Research) and FEDER (European Regional Development Fund)

Cerebrospinal fluid neopterin as a biomarker of neuroinflammatory diseases.

The elevation of neopterin in cerebrospinal fuid (CSF) has been reported in several neuroinfammatory disorders. However, it is not expected that neopterin alone can discriminate among diferent neuroinfammatory etiologies. We conducted an observational retrospective and case-control study to analyze the CSF biomarkers neopterin, total proteins, and leukocytes in a large cohort of pediatric patients with neuroinfammatory disorders. CSF samples from 277 subjects were included and classifed into four groups: Viral meningoencephalitis, bacterial meningitis, acquired immunemediated disorders, and patients with no-immune diseases (control group). CSF neopterin was analyzed with high-performance liquid chromatography. Microbiological diagnosis included bacterial CSF cultures and several specifc real-time polymerase chain reactions. Molecular testing for multiple respiratory pathogens was also included. Antibodies against neuronal and glial proteins were tested. Canonical discriminant analysis of the three biomarkers was conducted to establish the best discriminant functions for the classifcation of the diferent clinical groups. Model validation was done by biomarker analyses in a new cohort of 95 pediatric patients. CSF neopterin displayed the highest values in the viral and bacterial infection groups. By applying canonical discriminant analysis, it was possible to classify the patients into the diferent groups. Validation analyses displayed good results for neuropediatric patients with no-immune diseases and for viral meningitis patients, followed by the other groups. This study provides initial evidence of a more efcient approach to promote the timely classifcation of patients with viral and bacterial infections and acquired autoimmune disorders. Through canonical equations, we have validated a new tool that aids in the early and diferential diagnosis of these neuroinfammatory conditions