Bilateral Simultaneous Retinal Detachment in Pseudophakia

Cataract surgery is the most frequent surgical intervention, with approximately 700,000 operations per year in Germany alone. One of the most serious complications is retinal detachment, with a reported incidence rate of pseudophakic retinal detachment of 0.75-1.65%. We report the case of a patient who suffered from a simultaneous bilateral pseudophakic retinal detachment. Interestingly, the bilateral detachments in the left and the right eye started with only some hours' delay. He had no acute trigger for the retinal detachment and no risk factors besides the cataract surgery performed on both eyes some weeks earlier. Simultaneous bilateral retinal detachments will be more common, due to increasing numbers of cataract surgeries and the demographic development. We conclude that funduscopy should be regularly performed in mydriasis to avoid sight-threatening simultaneous bilateral retinal detachments

Bilateral Simultaneous Retinal Detachment in Pseudophakia

Cataract surgery is the most frequent surgical intervention, with approximately 700,000 operations per year in Germany alone. One of the most serious complications is retinal detachment, with a reported incidence rate of pseudophakic retinal detachment of 0.75-1.65%. We report the case of a patient who suffered from a simultaneous bilateral pseudophakic retinal detachment. Interestingly, the bilateral detachments in the left and the right eye started with only some hours' delay. He had no acute trigger for the retinal detachment and no risk factors besides the cataract surgery performed on both eyes some weeks earlier. Simultaneous bilateral retinal detachments will be more common, due to increasing numbers of cataract surgeries and the demographic development. We conclude that funduscopy should be regularly performed in mydriasis to avoid sight-threatening simultaneous bilateral retinal detachments

The antioxidant Trolox restores mitochondrial membrane potential and Ca2+-stimulated ATP production in human complex I deficiency

Malfunction of mitochondrial complex I caused by nuclear gene mutations causes early-onset neurodegenerative diseases. Previous work using cultured fibroblasts of complex-I-deficient patients revealed elevated levels of reactive oxygen species (ROS) and reductions in both total Ca2+ content of the endoplasmic reticulum (ERCa) and bradykinin(Bk)-induced increases in cytosolic and mitochondrial free Ca2+ ([Ca2+]C; [Ca2+]M) and ATP ([ATP]C; [ATP]M) concentration. Here, we determined the mitochondrial membrane potential (Δψ) in patient skin fibroblasts and show significant correlations with cellular ROS levels and ERCa, i.e., the less negative Δψ, the higher these levels and the lower ERCa. Treatment with 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) normalized Δψ and Bk-induced increases in [Ca2+]M and [ATP]M. These effects were accompanied by an increase in ERCa and Bk-induced increase in [Ca2+]C. Together, these results provide evidence for an integral role of increased ROS levels in complex I deficiency and point to the potential therapeutic value of antioxidant treatment

Impact of genetic and non-genetic factors on phenotypic diversity in NBAS-associated disease

Biallelic pathogenic variants in neuroblastoma-amplified sequence (NBAS) cause a pleiotropic multisystem disorder. Three clinical subgroups have been defined correlating with the localisation of pathogenic variants in the NBAS gene; variants affecting the C-terminal region of NBAS result in SOPH syndrome (short stature, optic atrophy, Pelger-Huët anomaly), variants affecting the Sec 39 domain are associated with infantile liver failure syndrome type 2 (ILFS2) and variants affecting the ß-propeller domain give rise to a combined phenotype. However, there is still unexplained phenotypic diversity across the three subgroups, challenging the current concept of genotype-phenotype correlations in NBAS-associated disease. Therefore, besides examining the genetic influence, we aim to elucidate the potential impact of pre-symptomatic diagnosis, emergency management and other modifying variables on the clinical phenotype. We investigated genotype-phenotype correlations in individuals sharing the same genotypes (n = 30 individuals), and in those sharing the same missense variants with a loss-of-function variant in trans (n = 38 individuals). Effects of a pre-symptomatic diagnosis and emergency management on the severity of acute liver failure (ALF) episodes also were analysed, comparing liver function tests (ALAT, ASAT, INR) and mortality. A strong genotype-phenotype correlation was demonstrated in individuals sharing the same genotype; this was especially true for the ILFS2 subgroup. Genotype-phenotype correlation in patients sharing only one missense variant was still high, though at a lower level. Pre-symptomatic diagnosis in combination with an emergency management protocol leads to a trend of reduced severity of ALF. High genetic impact on clinical phenotype in NBAS-associated disease facilitates monitoring and management of affected patients sharing the same genotype. Pre-symptomatic diagnosis and an emergency management protocol do not prevent ALF but may reduce its clinical severity

ZSCAN10 deficiency causes a neurodevelopmental disorder with characteristic oto-facial malformations

Neurodevelopmental disorders are major indications for genetic referral and have been linked to more than 1500 loci including genes encoding transcriptional regulators. The dysfunction of transcription factors often results in characteristic syndromic presentations; however, at least half of these patients lack a genetic diagnosis. The implementation of machine learning approaches has the potential to aid in the identification of new disease genes and delineate associated phenotypes. Next generation sequencing was performed in seven affected individuals with neurodevelopmental delay and dysmorphic features. Clinical characterization included reanalysis of available neuroimaging datasets and 2D portrait image analysis with GestaltMatcher. The functional consequences of ZSCAN10 loss were modelled in mouse embryonic stem cells (mESCs), including a knockout and a representative ZSCAN10 protein truncating variant. These models were characterized by gene expression and western blot analyses, chromatin immunoprecipitation and quantitative PCR (ChIP-qPCR) and immunofluorescence staining. Zscan10 knockout mouse embryos were generated and phenotyped. We prioritized bi-allelic ZSCAN10 loss-of-function variants in seven affected individuals from five unrelated families as the underlying molecular cause. RNA-sequencing analyses in Zscan10−/− mESCs indicated dysregulation of genes related to stem cell pluripotency. In addition, we established in mESCs the loss-of-function mechanism for a representative human ZSCAN10 protein truncating variant by showing alteration of its expression levels and subcellular localization, interfering with its binding to DNA enhancer targets. Deep phenotyping revealed global developmental delay, facial asymmetry and malformations of the outer ear as consistent clinical features. Cerebral MRI showed dysplasia of the semicircular canals as an anatomical correlate of sensorineural hearing loss. Facial asymmetry was confirmed as a clinical feature by GestaltMatcher and was recapitulated in the Zscan10 mouse model along with inner and outer ear malformations. Our findings provide evidence of a novel syndromic neurodevelopmental disorder caused by bi-allelic loss-of-function variants in ZSCAN10

Clinico-Genetic, Imaging and Molecular Delineation of COQ8A-Ataxia: A Multicenter Study of 59 Patients.

OBJECTIVE: To foster trial-readiness of coenzyme Q8A (COQ8A)-ataxia, we map the clinicogenetic, molecular, and neuroimaging spectrum of COQ8A-ataxia in a large worldwide cohort, and provide first progression data, including treatment response to coenzyme Q10 (CoQ10). METHODS: Cross-modal analysis of a multicenter cohort of 59 COQ8A patients, including genotype-phenotype correlations, 3D-protein modeling, in vitro mutation analyses, magnetic resonance imaging (MRI) markers, disease progression, and CoQ10 response data. RESULTS: Fifty-nine patients (39 novel) with 44 pathogenic COQ8A variants (18 novel) were identified. Missense variants demonstrated a pleiotropic range of detrimental effects upon protein modeling and in vitro analysis of purified variants. COQ8A-ataxia presented as variable multisystemic, early-onset cerebellar ataxia, with complicating features ranging from epilepsy (32%) and cognitive impairment (49%) to exercise intolerance (25%) and hyperkinetic movement disorders (41%), including dystonia and myoclonus as presenting symptoms. Multisystemic involvement was more prevalent in missense than biallelic loss-of-function variants (82-93% vs 53%; p = 0.029). Cerebellar atrophy was universal on MRI (100%), with cerebral atrophy or dentate and pontine T2 hyperintensities observed in 28%. Cross-sectional (n = 34) and longitudinal (n = 7) assessments consistently indicated mild-to-moderate progression of ataxia (SARA: 0.45/year). CoQ10 treatment led to improvement by clinical report in 14 of 30 patients, and by quantitative longitudinal assessments in 8 of 11 patients (SARA: -0.81/year). Explorative sample size calculations indicate that ≥48 patients per arm may suffice to demonstrate efficacy for interventions that reduce progression by 50%. INTERPRETATION: This study provides a deeper understanding of the disease, and paves the way toward large-scale natural history studies and treatment trials in COQ8A-ataxia. ANN NEUROL 2020;88:251-263

C. elegans ATAD-3 Is Essential for Mitochondrial Activity and Development

Contains fulltext : 80701.pdf (publisher's version ) (Open Access)BACKGROUND: Mammalian ATAD3 is a mitochondrial protein, which is thought to play an important role in nucleoid organization. However, its exact function is still unresolved. RESULTS: Here, we characterize the Caenorhabditis elegans (C. elegans) ATAD3 homologue (ATAD-3) and investigate its importance for mitochondrial function and development. We show that ATAD-3 is highly conserved among different species and RNA mediated interference against atad-3 causes severe defects, characterized by early larval arrest, gonadal dysfunction and embryonic lethality. Investigation of mitochondrial physiology revealed a disturbance in organellar structure while biogenesis and function, as indicated by complex I and citrate synthase activities, appeared to be unaltered according to the developmental stage. Nevertheless, we observed very low complex I and citrate synthase activities in L1 larvae populations in comparison to higher larval and adult stages. Our findings indicate that atad-3(RNAi) animals arrest at developmental stages with low mitochondrial activity. In addition, a reduced intestinal fat storage and low lysosomal content after depletion of ATAD-3 suggests a central role of this protein for metabolic activity. CONCLUSIONS: In summary, our data clearly indicate that ATAD-3 is essential for C. elegans development in vivo. Moreover, our results suggest that the protein is important for the upregulation of mitochondrial activity during the transition to higher larval stages

Genetic landscape of pediatric acute liver failure of indeterminate origin.

BACKGROUND AIMS Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, main causes are viral infections (12-16%) and inherited metabolic diseases (14-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. METHODS With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. RESULTS In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF (RALF). WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (46%), and in children with RALF (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8) and DGUOK (n=7) were the most frequent findings. When categorizing, most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%) and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplants. CONCLUSION This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics

Mutations in the Key Autophagy Tethering Factor EPG5 Link Neurodevelopmental and Neurodegenerative Disorders Including Early-Onset Parkinsonism

OBJECTIVE: Autophagy is a fundamental biological pathway with vital roles in intracellular homeostasis. During autophagy, defective cargoes including mitochondria are targeted to lysosomes for clearance and recycling. Recessive truncating variants in the autophagy gene EPG5 have been associated with Vici syndrome, a severe early-onset neurodevelopmental disorder with extensive multisystem involvement. Here, we aimed to delineate the extended, age-dependent EPG5-related disease spectrum.METHODS: We investigated clinical, radiological, and molecular features from the largest cohort of EPG5-related patients identified to date, complemented by experimental investigation of cellular and animal models of EPG5 defects.RESULTS: Through worldwide collaboration, we identified 211 patients, 97 of them previously unpublished, with recessive EPG5 variants. The phenotypic spectrum ranged from antenatally lethal presentations to milder isolated neurodevelopmental disorders. A novel Epg5 knock-in mouse model of a recurrent EPG5 missense variant featured motor impairments and defective autophagy in brain areas particularly relevant for the neurological disorders in milder presentations. Novel age-dependent neurodegenerative manifestations in our cohort included adolescent-onset parkinsonism and dystonia with cognitive decline, and myoclonus. Radiological features suggested an emerging continuum with brain iron accumulation disorders. Patient fibroblasts showed defects in PINK1-Parkin-dependent mitophagic clearance and α-synuclein overexpression, indicating a cellular basis for the observed neurodegenerative phenotypes. In Caenorhabditis elegans, EPG5 knockdown caused motor impairments, defective mitophagic clearance, and changes in mitochondrial respiration comparable to observations in C. elegans knockdown of parkinsonism-related genes.INTERPRETATION: Our findings illustrate a lifetime neurological disease continuum associated with pathogenic EPG5 variants, linking neurodevelopmental and neurodegenerative disorders through the common denominator of defective autophagy. ANN NEUROL 2025 ANN NEUROL 2025.</p