Explore the vast range of titles available.

Enzyme replacement therapy is currently considered the standard of care for the treatment of mucopolysaccharidoses (MPS) type I, II, VI, and IV. This approach has shown substantial efficacy mainly on somatic symptoms of the patients, but no benefit was found for other clinical manifestations, such as neurological involvement. New strategies are currently being tested to address these limitations, in particular to obtain sufficient therapeutic levels in the brain. Intrathecal delivery of recombinant enzymes or chimeric enzymes represent promising approaches in this respect. Further innovation will likely be introduced by the recent advancements in the knowledge of lysosomal biology and function. It is now clear that the clinical manifestations of MPS are not only the direct effects of storage, but also derive from a cascade of secondary events that lead to dysfunction of several cellular processes and pathways. Some of these pathways may represent novel therapeutic targets and allow for development of novel or adjunctive therapies for these disorders.

Background If symptomatic in infants, the autosomal recessive disease lysosomal acid lipase deficiency (LAL-D; sometimes called Wolman disease or LAL-D/Wolman phenotype) is characterized by complete loss of LAL enzyme activity. This very rare, rapidly progressive form of LAL-D results in severe manifestations leading to failure to thrive and death, usually by 6 months of age. We report results from 2 open-label studies of enzyme replacement therapy with sebelipase alfa, a recombinant human LAL, in infants with LAL-D: the phase 2/3 Sur v ival of LAL-D I nfants T reated With Sebelipase Al fa (VITAL) study (NCT01371825) and a phase 2 dose-escalation study (LAL-CL08 [CL08]; NCT02193867). In both, infants received once-weekly intravenous infusions of sebelipase alfa. Results The analysis population contained 19 patients (9 in VITAL; 10 in CL08). Kaplan–Meier estimates of survival to 12 months and 5 years of age were 79% and 68%, respectively, in the combined population, and the median age of surviving patients was 5.2 years in VITAL and 3.2 years in CL08. In both studies, median weight-for-age, length-for-age, and mid-upper arm circumference-for-age z scores increased from baseline to end of study. Decreases in median liver and spleen volume over time were noted in both studies. Short-term transfusion-free hemoglobin normalization was achieved by 100% of patients eligible for assessment in VITAL, in an estimated median (95% confidence interval [CI]) time of 4.6 (0.3–16.6) months. In CL08, short-term transfusion-free hemoglobin normalization was achieved by 70% of patients eligible for assessment, in an estimated median (95% CI) time of 5.5 (3.7–19.6) months. No patient discontinued treatment because of treatment-emergent adverse events. Most infusion-associated reactions (94% in VITAL and 88% in CL08) were mild or moderate in severity. Conclusions The findings of these 2 studies of infants with rapidly progressive LAL-D demonstrated that enzyme replacement therapy with sebelipase alfa prolonged survival with normal psychomotor development, improved growth, hematologic parameters, and liver parameters, and was generally well tolerated, with an acceptable safety profile. Plain Language Summary • Lysosomal acid lipase deficiency (LAL-D) is a rare, inherited disease in which fatty material (cholesterol and triglycerides) becomes trapped in cells throughout the body, causing organ damage. • Infants can experience a particularly aggressive form of this disease where the functioning of the liver and intestine is impaired, thus leading to an enlarged abdomen and failure to grow and thrive. • If left untreated, LAL-D in infants leads to death, usually by 6 months of age. • This publication reports the results from 2 studies involving 19 infants with rapidly progressive LAL-D; infants received once-weekly intravenous infusions of sebelipase alfa for up to 3 or 5 years, depending on the study. • Results show that with sebelipase alfa treatment, the likelihood of an infant with LAL-D surviving to 12 months of age is 79% and the likelihood of surviving to 5 years of age is 68%. • Throughout both studies, treatment with sebelipase alfa was associated with (1) improvements in growth (weight, length/height, and arm circumference), (2) improvements in liver function, and (3) a decrease in liver and spleen size. • All patients experienced 1 or more adverse events (unwanted side effects), most of which were mild or moderate in severity; no patient stopped receiving treatment because of these events.

Heterozygous mutations in the gene encoding RagD GTPase were shown to cause a novel autosomal dominant condition characterized by kidney tubulopathy and cardiomyopathy. We previously demonstrated that RagD, and its paralogue RagC, mediate a non-canonical mTORC1 signaling pathway that inhibits the activity of TFEB and TFE3, transcription factors of the MiT/TFE family and master regulators of lysosomal biogenesis and autophagy. Here we show that RagD mutations causing kidney tubulopathy and cardiomyopathy are “auto- activating”, even in the absence of Folliculin, the GAP responsible for RagC/D activation, and cause constitutive phosphorylation of TFEB and TFE3 by mTORC1, without affecting the phosphorylation of “canonical” mTORC1 substrates, such as S6K. By using HeLa and HK-2 cell lines, human induced pluripotent stem cell-derived cardiomyocytes and patient-derived primary fibroblasts, we show that RRAGD auto-activating mutations lead to inhibition of TFEB and TFE3 nuclear translocation and transcriptional activity, which impairs the response to lysosomal and mitochondrial injury. These data suggest that inhibition of MiT/TFE factors plays a key role in kidney tubulopathy and cardiomyopathy syndrome. Mutations in the RRAGD gene are causative of an autosomal dominant disorder characterized by kidney tubulopathy and cardiomyopathy. Here, the authors identify a new RRAGD P88L mutation, demonstrating that all the identified RRAGD mutations inhibit the nuclear translocation of MiT/TFE transcription factors, resulting in defective responses to lysosomal or mitochondrial damage.

Background GD and ASMD are lysosomal storage disorders that enter into differential diagnosis due to the possible overlap in their clinical manifestations. The availability of safe and effective enzymatic therapies has recently led many investigators to develop and validate new screening tools, such as algorithms, for the diagnosis of LSDs where the lack of disease awareness or failure to implement newborn screening results in a delayed diagnosis. Results the proposed algorithm allows for the clinical and biochemical differentiation between GD and ASMD. It is based on enzyme activity assessed on dried blood spots by multiplexed tandem mass spectrometry (MS/MS) coupled to specific biomarkers as second-tier analysis. Conclusions we believe that this method will provide a simple, convenient and sensitive tool for the screening of a selected population that can be used by pediatricians and other specialists (such as pediatric hematologists and pediatric hepatologists) often engaged in diagnosing these disorders.

Background Newborn screening (NBS) programs have significantly improved the health and outcomes of patients with inherited metabolic disorders (IMDs). Methods based on liquid chromatography/mass spectrometry (LC–MS/MS) analysis are viewed worldwide as the gold standard procedure for the expanded NBS programs for these disorders. Advanced molecular technologies point to genomic sequencing as an alternative and feasible strategy for the screening of genetic diseases, including IMDs. However, each of the two approaches has potential limitations when used as a first-tier analysis. In this study, we tested a workflow-based parallel biochemical and sequencing analyses to determine whether this approach could improve the diagnostic outcome. Results For each patient identified by LC–MS/MS as positive, we performed both the biochemical confirmatory tests and next-generation sequencing (NGS) procedures from the same Dried Blood Spot (DBS). NGS analysis was based on applying Exome Sequencing libraries, limiting the analysis to 105 actionable genes involved in IMDs. This allows overtaking the actual limitations of NBS on DBS, enhancing our capacity to identify variants that can drive a genetic disease. Through this approach, we could reach 100% of cases solved, with 37.9% of cases (41/108) for which the combination of the biochemical and NGS analysis was indispensable for a correct diagnosis. In total, we could identify 17 affected, 34 false positives, 12 individuals referred to us for maternal conditions. In 45 newborns the molecular analysis showed heterozygosity for mutations in one or more of the genes analyzed, with results compatible with the biochemical profile indicative of NBS positivity. Conclusions In this study, we validated the performance of the proposed workflow. The advantage of this approach is limiting molecular analysis only to positive newborns and using a restricted panel of 105 genes relevant for the expanded NBS, with a 100% rate of diagnosis and potential reduction of the costs related to NBS procedures and reduced impact on patients and families.

Severe skeletal muscle damage has been recently reported in patients with SARS-CoV-2 infection and as a rare vaccination complication. On Apr 28, 2021 a 68-year-old man who was previously healthy presented with an extremely severe rhabdomyolysis that occurred nine days following the first dose of SARS-CoV-2 ChAdOx1 nCov-19 vaccination. He had no risk factors, and denied any further assumption of drugs except for fermented red rice, and berberine supplement. The clinical scenario was complicated by a multi organ failure involving bone marrow, liver, lung, and kidney. For the rapid increase of the inflammatory markers, a cytokine storm was suspected and multi-target biologic immunosuppressive therapy was started, consisting of steroids, anakinra, and eculizumab, which was initially successful resulting in close to normal values of creatine phosphokinase after 17 days of treatment. Unfortunately, 48 days after the vaccination an accelerated phase of deterioration, characterized by severe multi-lineage cytopenia, untreatable hypotensive shock, hypoglycemia, and dramatic increase of procalcitonin (PCT), led to patient death. Physicians should be aware that severe and fatal rhabdomyolysis may occur after SARS-CoV2 vaccine administration.

Background Late-onset Pompe’s disease (LOPD) is a progressive treatable metabolic myopathy due to partial acid α-glucosidase (GAA) deficiency, with potential onset during the pediatric age. To date, Pompe’s disease is not widely included in newborn screening panels, so that clinical suspect remains essential for timely diagnosis and management. Clinical identification of LOPD was shown to be challenging in adult patients, whereas data in children and adolescents are scanty. We conducted an Italian nationwide multicentric survey in order to delineate the characteristics of LOPD in the pediatric population. This prompted us to propose a diagnostic algorithm to facilitate the identification of LOPD in pediatrics. Results The survey provided information on 38 Italian pediatric patients with a definite biochemical and molecular diagnosis of LOPD firstly suspected based on clinical approach. Nineteen patients (50%) reached medical attention because of clinical symptoms of LOPD (79% within 3 years of age; 21% at 3–18 years of age) and 19 (50%) because of incidental finding of asymptomatic hyperCKemia. All the 38 LOPD patients showed hyperCKemia (56%: range 500–1000 U/l; 18%; range 250–500 U/l; 18% range 1000–2000 U/l; 8% >2000 U/l), almost invariably accompained by concomitant hypertransaminasemia (91%). Main clinical symptoms before 3 years of age were inability to (1) sit at 8 months, (2) walk indipendently at 18 months, and (3) climb stairs at 30 months. Later pediatric presentations (3–18 years of age) were limitation to (1) get up from supine position, (2) perform sport activity, and (3) run. In symptomatic patients, diagnostic latency (i.e. the time interval between clinical onset and diagnosis of LOPD) ranged from < 1 year (58%) to 2–12 years (42%). Conclusions Clinical diagnosis of LOPD in pediatrics is challenging in spite of its frequent presentation within 3 years of age. A selective screening by measuring GAA activity on dried blood spot in the two main clinical diagnostic contexts of LOPD in pediatrics – namely (1) age-related myopathic symptoms or (2) asymptomatic hyperCKemia (and hypertransaminasemia) – will likely ensure diagnostic anticipation for those patients not screened for Pompe’s disease in the neonatal period.

Background Besides major clinical/biochemical features, neutropenia and inflammatory bowel disease (IBD) constitute common complications of Glycogen storage disease type Ib (GSD Ib). However, their management is still challenging. Although previous reports have shown benefit of empagliflozin administration on neutropenia, no follow-up data on bowel (macro/microscopic) morphology are available. We herein present for the first time longitudinal assessment of bowel morphology in a GSD Ib child suffering from Crohn disease-like enterocolitis treated with empagliflozin. Case presentation A 14-year-old boy with GSD Ib and severe IBD was (off-label) treated with empagliflozin (20 mg/day) after informed oral and written consent was obtained from the patient’s parents. No adverse events were noted. Clinical symptoms and stool frequency improved within the first week of treatment. Pediatric Crohn disease activity index (PCDAI) normalised within the first month of treatment. Abdomen magnetic resonance imaging (MRI) performed 3 months after treatment initiation showed dramatic decrease in disease activity and length. Similar findings were reported on histology at 5.5 months. At 7.5 months hemoglobin levels normalised and fecal calprotectin almost normalised. Improved neutrophil count, metabolic control and quality of life were also noted. G-CSF dose was decreased by 33% and the patient was partly weaned from tube feeding. Conclusions This is the first report presenting extensive gastrointestinal morphology follow-up in a GSD Ib patient receiving empagliflozin. The present case suggests that empagliflozin can be safe and effective in inducing IBD remission in GSD Ib patients and can even postpone surgery. Future studies are required to confirm its effect over time and assess its benefit in various disease stages. The development of an international collaborating networks for systematic data collection is worthy.

Lysosomal storage diseases (LSDs) are rare inherited metabolic diseases characterized by an abnormal accumulation of various toxic materials in the cells as a result of enzyme deficiencies leading to tissue and organ damage. Among clinical manifestations, cardiac diseases are particularly important in Pompe glycogen storage diseases (PD), in glycosphingolipidosis Fabry disease (FD), and mucopolysaccharidoses (MPS). Here, we evaluated the occurrence of aortopathy in knock out (KO) mouse models of three different LSDs, including PD, FD, and MPS IIIB. We measured the aortic diameters in 15 KO male mice, 5 for each LSD: 5 GLA-/- mice for FD, 5 NAGLU-/- mice for MPS IIIB, 5 GAA-/- mice for PD, and 15 wild type (WT) mice: 5 for each strain. In order to compare the aortic parameters between KO and WT mice deriving from the same colonies, different diameters were echocardiographically measured: aortic annulus, aortic sinus, sino-tubular junction, ascending aorta, aortic arch and descending aorta. Storage material content and aortic defects of the KO mice were also analyzed by histology, when available. Compared to their correspondent WT mice: GAA-/- mice showed greater diameters of ascending aorta (1.61mm vs. 1.11mm, p-value = 0.01) and descending aorta (1.17mm vs 1.02mm, p-value 0.04); GLA-/- mice showed greater diameters of aortic annulus (1.35mm vs. 1.22mm, p-value = 0.01), sinus of Valsalva (1.6mm vs. 1.38mm, p-value<0.01), ascending aorta (1.57mm vs. 1.34mm, p-value<0.01), aortic arch (1.36mm vs. 1.22mm, p-value = 0.03) and descending aorta (1.29mm vs. 1.11mm, p-value<0.01); NAGLU-/- mice showed greater diameters of sinus of Valsalva (1.46mm vs. 1.31mm, p-value = 0.05), ascending aorta (1.42mm vs. 1.29mm, p-value<0.01), aortic arch (1.34mm vs. 1.28mm, p-value<0.01) and descending aorta (1.18mm vs. 1.1mm, p-value 0.01). We evaluated for the first time the aortic diameters in 3 LSD mouse models and identified different aortopathy patterns, in concordance with recent human findings. Our results are relevant in view of using KO mouse models for efficiently testing the efficacy of new therapies on distinct cardiovascular aspects of LSDs.