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Background: Biochemical testing is a common first-tier approach in the setting of genetic evaluation of patients with unexplained developmental delay. However, results can be unclear, and a plan for second-tier analysis must be determined based on the patient's biochemical results and clinical presentation - in many cases, triggering a diagnostic odyssey. Case presentation: A male patient from the United States presenting with unexplained developmental delay, microcephaly, hypotonia, and feeding difficulties was referred for clinical genetic evaluation at age 8 months. Biochemical testing revealed an isolated marked elevation of glutaric acid on urine organic acid profile, without elevations of related metabolites. Further testing included GCDH sequencing, a neurometabolic gene panel, chromosomal microarray, Prader Willi/Angelman testing, and lysosomal disease enzyme panel, all of which were non-diagnostic. The patient had persistent developmental delay and hypotonia, dystonia, sensorineural hearing loss, and abnormal brain myelination on magnetic resonance imaging. Whole exome sequencing (WES) was performed and revealed a dual diagnosis of glutaric aciduria III (GA III) and BCAP31-related disorder, an X-linked intellectual disability syndrome, caused by a novel pathogenic variant. Conclusions: GA III has historically been considered clinically benign, with few reported cases. This patient's presenting symptoms were similar to those commonly seen in GA I and GA II, however the biochemical abnormalities were not consistent with these disorders, prompting additional molecular and biochemical testing. Ultimately, WES confirmed a diagnosis of BCAP31-related syndrome, a rare neurological disorder, which explained the patient's presenting symptoms. WES also identified a secondary diagnosis of GA III. We present a patient with two rare genetic conditions, highlighting the importance of deep phenotyping and the utility of WES in the setting of a patient with dual genetic diagnoses.
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A genetic diagnosis of primary cardiomyopathies can be a long-unmet need in patients with complex phenotypes. We investigated a three-generation family with cardiomyopathy and various extracardiac abnormalities that had long sought a precise diagnosis. The 41-year-old proband had hypertrophic cardiomyopathy (HCM), left ventricular noncompaction, myocardial fibrosis, arrhythmias, and a short stature. His sister showed HCM, myocardial hypertrabeculation and fibrosis, sensorineural deafness, and congenital genitourinary malformations. Their father had left ventricular hypertrophy (LVH). The proband's eldest daughter demonstrated developmental delay and seizures. We performed a clinical examination and whole-exome sequencing for all available family members. All patients with HCM/LVH shared a c.4411-2A>C variant in ALPK3, a recently known HCM-causative gene. Functional studies confirmed that this variant alters ALPK3 canonical splicing. Due to extracardiac symptoms in the female patients, we continued the search and found two additional single-gene disorders. The proband's sister had a p.Trp329Gly missense in GATA3, linked to hypoparathyroidism, sensorineural deafness, and renal dysplasia; his daughter had a p.Ser251del in WDR45, associated with beta-propeller protein-associated neurodegeneration. This unique case of three monogenic disorders in one family shows how a comprehensive approach with thorough phenotyping and extensive genetic testing of all symptomatic individuals provides precise diagnoses and appropriate follow-up, embodying the concept of personalized medicine. We also present the first example of a splicing functional study for ALPK3 and describe the genotype-phenotype correlations in cardiomyopathy.
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Linhagem , Humanos , Feminino , Masculino , Adulto , Cardiomiopatias/genética , Cardiomiopatias/diagnóstico , Sequenciamento do Exoma , Anormalidades Múltiplas/genética , Perda Auditiva Neurossensorial/genética , Fenótipo , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/diagnósticoRESUMO
This case report chronicles the diagnostic odyssey and resolution of a 27-year-old female with a complex neurodevelopmental disorder (NDD) using Whole Exome Sequencing (WES). The patient presented to a precision medicine clinic with multiple diagnoses including intellectual disability, autism spectrum disorder (ASD), obsessive-compulsive disorder (OCD), tics, seizures, and pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). Although this patient previously had chromosomal microarray and several single-gene tests, the underlying cause of this patient's symptoms remained elusive. WES revealed a pathogenic missense mutation in the HNRNPU gene, associated with HNRNPU-related neurodevelopmental disorder (HNRNPU-NDD) and developmental and epileptic encephalopathy-54 (DEE54, OMIM: # 617391). Following this diagnoses, other treating clinicians identified additional indications for genetic testing, however, as the WES data was readily available, the clinical team was able to re-analyze the WES data to address their inquiries without requiring additional tests. This emphasizes the pivotal role of WES in expediting diagnoses, reducing costs, and providing ongoing clinical utility throughout a patient's life. Accessible WES data in primary care settings can enhance patient care by informing future genetic inquiries, enhancing coordination of care, and facilitating precision medicine interventions, thereby mitigating the burden on families and the healthcare system.
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The COVID-19 pandemic had a disproportionate impact on ethnically minoritised and other marginalised communities, yet little is known about the impacts of long COVID-19 (LC) on this group. Living with LC takes its toll both physically, emotionally and financially and even more so when a diagnosis is hard to come by. By using qualitative interviews centring the view of undiagnosed and marginalised communities already classed as 'underserved' in the medical literature, we show the range of barriers and impacts faced by these groups in the UK, and the strategies of resilience they use. Whether trapped on a 'diagnostic odyssey' at the level of primary care, struggling to maintain employment and businesses, or managing family commitments, we argue many minoritised communities are caught in a liminal space of misrecognition, invalidation and ambiguity. We show how these impacts are generated by tensions and challenges in the process and categorisation of diagnosis, and how this effects the daily lives of many individuals already on the receiving end of health inequity. We also offer some examples and suggestions for best practices.
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OBJECTIVE: To elucidate the patient's journey to epilepsy surgery and identify the risk factors contributing to surgical delay in pediatric patients with drug-resistant epilepsy (DRE) due to focal cortical dysplasia (FCD). METHODS: A retrospective review was conducted of 93 pediatric patients who underwent curative epilepsy surgery for FCD between January 2012 and March 2023 at a tertiary epilepsy center. The Odyssey plot demonstrated the treatment process before epilepsy surgery, including key milestones of epilepsy onset, first hospital visit, epilepsy diagnosis, MRI diagnosis, DRE diagnosis, and surgery. The primary outcome was surgical delay; the duration from DRE to surgery. Multivariate linear regression models were used to examine the association between surgical delay and clinical, investigative, and treatment characteristics. RESULTS: The median age at seizure onset was 1.3 years (interquartile range [IQR] 0.14-3.1), and at the time of surgery, it was 6 years (range 1-11). Notably, 46% experienced surgical delays exceeding two years. The Odyssey plot visually highlighted that surgical delay comprised a significant portion of the patient journey. Although most patients underwent MRI before referral, MRI abnormalities were identified before referral only in 39% of the prolonged group, compared to 70% of the non-prolonged group. Multivariate analyses showed that delayed notification of MRI abnormalities, longer duration from epilepsy onset to DRE, older age at onset, number of antiseizure medications tried, and moderate to severe intellectual disability were significantly associated with prolonged surgical delay. CONCLUSION: Pediatric DRE patients with FCD experienced a long journey until surgery. Early and accurate identification of MRI abnormalities is important to minimize surgical delays.
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Epilepsia Resistente a Medicamentos , Imageamento por Ressonância Magnética , Malformações do Desenvolvimento Cortical , Tempo para o Tratamento , Humanos , Masculino , Feminino , Pré-Escolar , Estudos Retrospectivos , Epilepsia Resistente a Medicamentos/cirurgia , Criança , Lactente , Fatores de Risco , Malformações do Desenvolvimento Cortical/cirurgia , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Tempo para o Tratamento/estatística & dados numéricos , Adolescente , Procedimentos Neurocirúrgicos , Epilepsia/cirurgia , Epilepsia/etiologia , Displasia Cortical FocalRESUMO
Obtaining a genetic diagnosis of a primary mitochondrial disease (PMD) is often framed as a diagnostic odyssey. Yet, even after receiving a diagnosis, parents of affected children experience ongoing therapeutic and prognostic uncertainty and considerable psychosocial challenges. Semi-structured interviews (N = 24) were conducted with parents of 13 children (aged 2-19 years) with a genetically confirmed PMD. Paternal (N = 11) and maternal (N = 13) perspectives were obtained, and thematic analysis was performed on all interviews. A genetic diagnosis was valuable and empowering for parents, despite eliciting varied emotional responses. While the diagnosis helped focus management decisions, families often felt overwhelmed and unsupported in navigating the healthcare system. Most parents reported a serious impact on their romantic relationship. The sources of social support varied, with a preference for established friendship and family support networks over disease-specific community support groups. Most parents favored prenatal genetic testing in the event of a future pregnancy. This study provides insight into the lived experiences of parents after a genetic diagnosis of PMD in their children. The findings draw awareness to supportive care needs and highlight important gaps that should be addressed to ensure that parents feel supported within a holistic framework of management for PMDs.
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BACKGROUND: The 'diagnostic odyssey' is a common challenge faced by patients living with rare diseases and poses a significant burden for patients, their families and carers, and the healthcare system. The diagnosis of rare diseases in clinical settings is challenging, with patients typically experiencing a multitude of unnecessary tests and procedures. To improve diagnosis of rare disease, clinicians require evidence-based guidance on when their patient may be presenting with a rare disease. This study aims to identify common experiences amongst patients with rare diseases, to inform a series of 'red flags' that can aid diagnosis of rare diseases in non-specialist settings. A questionnaire was developed by Medics for Rare Diseases, informed by the experiences of clinicians, rare disease patients and patient advocates, and was shared with UK-based rare disease patient groups. Study participants were engaged via social media platforms, blogs and email newsletters of three umbrella rare disease organisations. The questionnaire, comprising 22 questions, was designed to identify typical experiences relating to physical and psychosocial manifestations and presentation of disease, patient interactions with healthcare providers, and family history. RESULTS: Questionnaire responses were received from 79 different rare disease patient groups and the common experiences identified were used to inform seven red flags of rare disease: multi-system involvement (3 or more); genetic inheritance pattern; continued presentation throughout childhood and adulthood; difficulties at school, especially relating to absences, difficulty participating in physical education and experiences of bullying or social isolation; multiple specialist referrals; extended period with unexplained symptoms; and misdiagnosis. In light of the red flags identified, recommendations for primary care and education settings have been proposed, focusing on the need for holistic assessment and awareness of both physical and psychosocial factors. CONCLUSIONS: This study identified key commonalities experienced by patients with rare disease across physical and psychosocial domains, in addition to understanding patients' history and experiences with healthcare providers. These findings could be used to develop a clinical decisionmaking tool to support non-specialist practitioners to consider when their patient may have an undiagnosed rare condition, which may minimise the challenges of the 'diagnostic odyssey' and improve the patient experience.
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Atenção à Saúde , Doenças Raras , Humanos , Criança , Doenças Raras/diagnóstico , Cuidadores , Pessoal de SaúdeRESUMO
Angelman syndrome (AS, MIM #105830) is a neurodevelopmental disorder characterized by severe intellectual disability, profound developmental delay, movement or balance problems, an excessively cheerful disposition, and seizures. AS results from inadequate expression of the maternal UBE3A gene (MIM #601623), which encodes an E3 ligase in the ubiquitin-proteasome pathway. Here we present the case of two sisters with features consistent with AS who had negative methylation analyses. An autism/intellectual disability expanded panel revealed a maternally inherited novel UBE3A (NM_001354506.2) variant c.2443C>T p.(Pro815Ser) in both patients that was initially classified as a variant of uncertain significance. The patients were enrolled in Indiana University's Undiagnosed Rare Disease Clinic (URDC) to further investigate the variant. Additional data, including deep phenotyping, familial segregation analysis, and in silico studies, suggest that the variant is likely pathogenic. 3D modeling studies based on the available crystal structure revealed that the Pro815Ser variant can introduce more flexibility into the protein and alter its enzymatic activity. Recent literature confirms the pathogenic nature of the variant. Reanalysis of the UBE3A variant has heightened existing knowledge of AS and has offered this family an end to their diagnostic odyssey.
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Síndrome de Angelman , Irmãos , Ubiquitina-Proteína Ligases , Humanos , Síndrome de Angelman/genética , Síndrome de Angelman/diagnóstico , Feminino , Ubiquitina-Proteína Ligases/genética , Doenças Raras/genética , Doenças Raras/diagnóstico , Fenótipo , Linhagem , Mutação , Criança , Deficiência Intelectual/genética , Deficiência Intelectual/diagnóstico , Predisposição Genética para Doença , Pré-EscolarRESUMO
BACKGROUND: Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by progressive muscle weakness and atrophy. Clinical trial data suggest early diagnosis and treatment are critical. The purpose of this study was to evaluate neurology appointment wait times for newborn screening identified infants, pediatric cases mirroring SMA symptomatology, and cases in which SMA is suspected by the referring physician. Approaches for triaging and expediting referrals in the US were also explored. METHODS: Cure SMA surveyed healthcare professionals from two cohorts: (1) providers affiliated with SMA care centers and (2) other neurologists, pediatric neurologists, and neuromuscular specialists. Surveys were distributed directly and via Medscape Education, respectively, between July 9, 2020, and August 31, 2020. RESULTS: Three hundred five total responses were obtained (9% from SMA care centers and 91% from the general recruitment sample). Diagnostic journeys were shorter for infants eventually diagnosed with SMA Type 1 if they were referred to SMA care centers versus general sample practices. Appointment wait times for infants exhibiting "hypotonia and motor delays" were significantly shorter at SMA care centers compared to general recruitment practices (p = 0.004). Furthermore, infants with SMA identified through newborn screening were also more likely to be seen sooner if referred to a SMA care center versus a general recruitment site. Lastly, the majority of both cohorts triaged incoming referrals. The average wait time for infants presenting at SMA care centers with "hypotonia and motor delay" was significantly shorter when initial referrals were triaged using a set of "key emergency words" (p = 0.036). CONCLUSIONS: Infants directly referred to a SMA care center versus a general sample practice were more likely to experience shorter SMA diagnostic journeys and appointment wait times. Triage guidelines for referrals specific to "hypotonia and motor delay" including use of "key emergency words" may shorten wait times and support early diagnosis and treatment of SMA.
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PURPOSE: Genomic medicine can end diagnostic odysseys for patients with complex phenotypes; however, limitations in insurance coverage and other systemic barriers preclude individuals from accessing comprehensive genetics evaluation and testing. METHODS: The Texome Project is a 4-year study that reduces barriers to genomic testing for individuals from underserved and underrepresented populations. Participants with undiagnosed, rare diseases who have financial barriers to obtaining exome sequencing (ES) clinically are enrolled in the Texome Project. RESULTS: We highlight the Texome Project process and describe the outcomes of the first 60 ES results for study participants. Participants received a genetic evaluation, ES, and return of results at no cost. We summarize the psychosocial or medical implications of these genetic diagnoses. Thus far, ES provided molecular diagnoses for 18 out of 60 (30%) of Texome participants. Plus, in 11 out of 60 (18%) participants, a partial or probable diagnosis was identified. Overall, 5 participants had a change in medical management. CONCLUSION: To date, the Texome Project has recruited a racially, ethnically, and socioeconomically diverse cohort. The diagnostic rate and medical impact in this cohort support the need for expanded access to genetic testing and services. The Texome Project will continue reducing barriers to genomic care throughout the future study years.
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Sequenciamento do Exoma , Testes Genéticos , Populações Vulneráveis , Humanos , Feminino , Masculino , Testes Genéticos/métodos , Adulto , Pessoa de Meia-Idade , Área Carente de Assistência Médica , Exoma/genética , Acessibilidade aos Serviços de Saúde , Adolescente , Genômica/métodos , Adulto Jovem , IdosoRESUMO
The Kondo-Fu type of spondyloepiphyseal dysplasia (SEDKF) is a rare skeletal dysplasia caused by homozygous or compound heterozygous mutations in the MBTPS1 gene. The MBTPS1 gene encodes a protein that is involved in the regulation of cholesterol and fatty acid metabolism. Mutations in MBTPS1 can lead to reduced levels of these lipids, which can have a number of effects on development, including skeletal anomalies, growth retardation, and elevated levels of blood lysosomal enzymes. This work reports the case of a 5-year-old girl with SEDKF. The patient had a severely short stature and a number of skeletal anomalies, including kyphosis, pectus carinatum, and reduced bone mineral density. She also had early onset cataracts and inguinal hernias. Genetic testing revealed two novel compound heterozygous variants in the MBTPS1 gene. These variants are predicted to disrupt the function of the MBTPS1 protein, which is consistent with the patient's clinical presentation. This case report adds to the growing body of evidence that mutations in the MBTPS1 gene are causal of SEDKF. We summarized the features of previous reported cases (with age ranges from 4 to 24 years) and identified that 80% had low stature, 70% low weight, 80% had bilateral cataracts and 70% showed Spondyloepiphyseal dysplasia on X-rays. The findings of this study suggest that SEDKF is a clinically heterogeneous disorder that can present with a variety of features. Further studies are needed to better understand the underlying mechanisms of SEDKF and to develop more effective treatments.
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BACKGROUND: Familial hemophagocytic lymphohistiocytosis (FHL) is an immunological disorder characterized by overactivation of macrophages and T lymphocytes. This autosomal recessive condition has been characterized into multiple types depending on the genetic etiology. FHL type 3 is associated with bi-allelic pathogenic variants in the UNC13D gene. CASE PRESENTATION: We present a 12-year diagnostic odyssey for a family with FHL that signifies the advances of FHL genetic testing in a clinical genetic diagnostic laboratory setting. We describe the first case of a large UNC13D gross deletion in trans to a nonsense variant in a family with FHL3, which may have been mediated by Alu elements within introns 12 and 25 of the UNC13D gene. CONCLUSIONS: This case highlights the importance of re-evaluating past genetic testing for a patient and family as test technology evolves in order to end a diagnostic odyssey.
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Linfo-Histiocitose Hemofagocítica , Humanos , Alelos , Testes Genéticos , Íntrons , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/genética , Proteínas de Membrana/genética , Mutação , CriançaRESUMO
Elevated rates of consanguinity and inbreeding are responsible for the high prevalence of recessively inherited diseases among inbred populations including Tunisia. In addition, the co-occurrence of two of these conditions, called also comorbidity, within the same individual or in members of the same family are often described in Tunisia which is challenging for diagnosis. The high throughput sequencing has improved the diagnosis of inherited diseases. We report here on a 32-year-old woman born to consanguineous parents. She presented with congenital ichthyosis and muscular dystrophy. She was primarily suspected as suffering from Chanarin-Dorfman syndrome (CDS) with unusual form. Screening of founder mutations allowed only the elucidation of the molecular etiology of Ichthyosis. As the result was inconclusive, Whole Exome Sequencing (WES) was conducted. WES data analysis led to the identification of a mutation in the CAPN3 gene underlying limb-girdle muscular dystrophy type 2A (LGMD2A). Sanger sequencing confirmed the familial segregation of mutations. This work presents the first case worldwide of individual comorbidity of bathing suit ichthyosis and LGMD2A. The co-occurrence of two diseases should be systematically considered when establishing a diagnosis especially in consanguineous populations. WES is a powerful tool for molecular diagnosis in particular for revealing comorbidities and rectifying the diagnosis.
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Distrofia Muscular do Cíngulo dos Membros , Feminino , Humanos , Adulto , Sequenciamento do Exoma , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação , ComorbidadeRESUMO
BACKGROUND AND OBJECTIVES: A gap exists between difficulty in diagnosis and importance of early recognition and intervention in pediatric Guillain-Barré syndrome (GBS). Therefore, this study aimed to establish a diagnostic odyssey plot that allows "at-a-glance" overview of the diagnostic odyssey of GBS in children, including overall diagnostic delay, physician-related and patient-related diagnostic delays, and length and frequency of diagnostic errors. METHODS: In this single-center retrospective cohort study, standardized data were obtained from children with GBS from 2003 to 2020. Overall diagnostic delay (time between symptom onset and diagnosis), physician-related diagnostic delay (time between the first medical visit and diagnosis), and patient-related diagnostic delay (time between symptom onset and the first medical visit) were analyzed. RESULTS: The study examined a total of 21 patients (11 men, median age 4.5 years). Overall, there were 40 misdiagnoses among 17 patients, while four were diagnosed correctly at the first visit. The overall diagnostic delay was 9 days [interquartile range (IQR), 6-17 days]. Physician-related diagnostic delay, but not patient-related diagnostic delay, was correlated with the overall diagnostic delay. Patients in the late-diagnosed group were more frequently misdiagnosed during their diagnostic odyssey than patients in the other groups. Risk factors associated with diagnostic delay included delayed onset of weakness and sensory deficits, absence of swallowing problems, and misdiagnosis as orthopedic disorders or viral infections. DISCUSSION: A unique diagnostic odyssey exists in pedaitric GBS. Several clinical risk factors were associated with the diagnostic delay.
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Síndrome de Guillain-Barré , Masculino , Humanos , Criança , Pré-Escolar , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/complicações , Estudos Retrospectivos , Diagnóstico Tardio , Erros de DiagnósticoRESUMO
The diagnostic odyssey for people living with rare diseases (PLWRD) is often prolonged for myriad reasons including an initial failure to consider rare disease and challenges to systemically and systematically identifying and tracking undiagnosed diseases across the diagnostic journey. This often results in isolation, uncertainty, a delay to targeted treatments and increase in risk of complications with significant consequences for patient and family wellbeing. This article aims to highlight key time points to consider a rare disease diagnosis along with elements to consider in the potential operational classification for undiagnosed rare diseases during the diagnostic odyssey. We discuss the need to create a coding framework that traverses all stages of the diagnostic odyssey for PLWRD along with the potential benefits this will have to PLWRD and the wider community.
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Receiving a genetic diagnosis can be challenging for parents as they learn to cope and adapt to this news. They often experience a myriad of emotions ranging from shock to relief. Yet overwhelmingly, parents report a negative experience with this process. Factors that improve parental satisfaction include being provided written information, emotional and psychosocial support, and connections with other parents. Genetics care providers are particularly equipped to solicit parental needs and provide support before, during, and after receiving a diagnosis. This review will provide suggestions and recommendations for supporting parents throughout the diagnostic testing experience and receiving a genetic diagnosis.
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Testes Genéticos , Aprendizagem , Humanos , Pais , RedaçãoRESUMO
The "odyssey plot" was used to visualize referral delays in epilepsy surgery. Participants were 36 patients (19 males; 13-67 years, median 27 years) with mesial temporal lobe epilepsy with hippocampal sclerosis (HS) who underwent resection surgery. The "referral odyssey plot" included five clinical episodes: seizure onset (T1), first visits to a non-epileptologist (T2) and to an epileptologist (T3), first admission to our epilepsy monitoring unit (EMU) (T4), and resection surgery (T5). For each patient, we identified the first seizure type: the physician who first diagnosed focal aware seizure (FAS), focal impaired awareness seizure (FIAS), focal to bilateral tonic-clonic seizure (FBTCS), and radiologically suspected HS. Within the overall delay (T1-T5, median 18 years; interquartile range [IQR] 14), non-epileptologist's delay (T2-T3, 11.5 years; IQR 12.25) was far (p < 0.0001) longer than patient's (T1-T2, 0 year; IQR 2.25), epileptologist's (T3-T4, 1 year; IQR 4), or after-EMU delay (T4-T5, 1 year; IQR 1). FAS onset cases had significantly longer T1-T2 (N = 5, median 7 years; IQR 6) than FIAS (N = 22, 0 year; IQR 1, p < 0.005) or FBTCS onset cases (N = 9, 0 year; IQR 0, p < 0.001). FAS was correctly diagnosed first by non-epileptologists in 17.9%, by out-patient epileptologists in 35.7%, and at the EMU in 46.4%. FIAS was correctly diagnosed first by non-epileptologists in 94.4% and by out-patient epileptologists in 5.6%. Non-epileptologists diagnosed FBTCS in all cases. HS was diagnosed by non-epileptologists in 13.9%, by out-patient epileptologists in 47.2%, and at the EMU in 38.9%. Early referral to epileptologists is most critical for early surgery. Early utilization of the EMU is highly recommended because FAS is often overlooked by outpatient epileptologists. The odyssey plot will be useful to improve the healthcare system for other types of epilepsy.
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Introduction: Rare genetic diseases are a major cause for severe illness in children. Whole exome sequencing (WES) is a powerful tool for identifying genetic causes of rare diseases. For a better and faster assessment of the vast number of variants that are identified in the index patient in WES, parental sequencing can be applied ("trio WES"). Methods: We assessed the diagnostic rate of routine trio WES including analysis of copy number variants in 224 pediatric patients during an evaluation period of three years. Results: Trio WES provided a diagnosis in 67 (30%) of all 224 analysed children. The turnaround time of trio WES analysis has been reduced significantly from 41 days in 2019 to 23 days in 2021. Copy number variants could be identified to be causative in 10 cases (4.5%), underlying the importance of copy number variant analysis. Variants in three genes which were previously not associated with a clinical condition (GAD1, TMEM222 and ZNFX1) were identified using the matching tool GeneMatcher and were part of the first description of a new syndrome. Discussion: Trio WES has proven to have a high diagnostic yield and to shorten the process of identifying the correct diagnosis in paediatric patients. Re-evaluation of all 224 trio WES 1-3 years after initial analysis did not establish new diagnoses. Initiating (trio) WES as a first-tier diagnostics including copy number variant detection should be considered as early as possible, especially for children treated in ICU, if a monogenetic disease is suspected.
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BACKGROUND: Advances in genomics provide improved opportunities for diagnosis of complex neurogenetic disorders, yet the optimal approach to translate these benefits to the outpatient clinic is unclear. AIMS: We retrospectively reviewed referral indications and outcomes of an integrated multidisciplinary team (MDT) clinic pathway for adults with suspected neurogenetic disorders. The associated cost implications were estimated. METHODS: Consecutive patients who attended the neurogenomics clinic from January 2017 to April 2020 were included. The clinic comprised neurologists, clinical geneticists and genetic counsellors, who assessed each patient concurrently. RESULTS: Ninety-nine new patients were referred spanning 45 different clinical diagnoses. Following MDT clinical assessment, 23% (23/99) of referral diagnoses were revised prior to molecular testing. Eighty-one patients (82%) underwent genetic testing, including 43 exome-based panels, 15 whole-genome sequencing, 14 single gene tests, 27 repeat-primed polymerase chain reaction testing and two chromosomal microarrays. Overall, 33/99 patients (33%) received a diagnosis, either a molecular diagnosis (n = 24, of which 22 were diagnostic and two were predictive) or a clinical diagnosis (n = 9). Of the clinical diagnosis cohort, five patients received a diagnosis without molecular testing and four patients whose negative testing (one diagnostic and three predictive) allowed exclusion of genetic differentials and, hence, confirmation of clinical diagnoses. The diagnostic rate following MDT and diagnostic testing was 30% (28/94), excluding the five predictive testing cases. MDT assessment aligned with eventual molecular diagnoses in 96% of cases. The estimated average costs were AU$1386 per patient undergoing MDT assessment and AU$4159 per diagnosis achieved. CONCLUSIONS: We present an integrated multidisciplinary neurogenomics clinic pathway providing a diagnostic yield of 33% (30% excluding predictive testing cases), with costing implications. The relatively high diagnostic yield may be attributed to multidisciplinary input integrating accurate phenotyping of complex disorders and interpretation of genomic findings.