Storage Disease Research Articles

Acidified drinking water improves motor function, prevents tremors and changes disease trajectory in Cln2R207X mice, a model of late infantile Batten disease

Batten disease is a group of mostly pediatric neurodegenerative lysosomal storage disorders caused by mutations in the CLN1–14 genes. We have recently shown that acidified drinking water attenuated neuropathological changes and improved motor function in the Cln1R151X and Cln3−/− mouse models of infantile CLN1 and juvenile CLN3 diseases. Here we tested if acidified drinking water has beneficial effects in Cln2R207X mice, a nonsense mutant model of late infantile CLN2 disease. Cln2R207X mice have motor deficits, muscle weakness, develop tremors, and die prematurely between 4 and 6 months of age. Acidified water administered to Cln2R207X male mice from postnatal day 21 significantly improved motor function, restored muscle strength and prevented tremors as measured at 3 months of age. Acidified drinking water also changed disease trajectory, slightly delaying the death of Cln2R207X males and females. The gut microbiota compositions of Cln2R207X and wild-type male mice were markedly different and acidified drinking water significantly altered the gut microbiota of Cln2R207X mice. This suggests that gut bacteria might contribute to the beneficial effects of acidified drinking water. Our study demonstrates that drinking water is a major environmental factor that can alter disease phenotypes and disease progression in rodent disease models.

Niemann-Pick Disease With Bilateral Adrenal Mass

Abstract Niemann–Pick disease (NPD) is a heterogeneous group of lysosomal storage disorders with autosomal recessive inheritance pattern. There are 4 types of NPD. Patients with NPD type B generally have better prognosis, allowing them to survive into adulthood. They have a widespread clinical presentation, affecting multiple organs but rarely neurological involvement. Here, we describe the case of a 38-year-old woman with unexplained hepatosplenomegaly and young hypertensive intracranial bleed. Evaluation for young hypertension further revealed a nonfunctional bilateral adrenal mass and gross hepatosplenomegaly. NPD was confirmed through dried blood spot investigation. It showed low activity of acid sphingomyelinase and genetic testing also detected 2 pathogenic mutations. She is being managed by a multidisciplinary team for supportive treatment that includes regular symptoms monitoring and genetic counseling.

A one-year pilot study comparing direct-infusion high resolution mass spectrometry based untargeted metabolomics to targeted diagnostic screening for inherited metabolic diseases.

Background: Early diagnosis of inherited metabolic diseases (IMDs) is important because treatment may lead to reduced mortality and improved prognosis. Due to their diversity, it is a challenge to diagnose IMDs in time, effecting an emerging need for a comprehensive test to acquire an overview of metabolite status. Untargeted metabolomics has proven its clinical potential in diagnosing IMDs, but is not yet widely used in genetic metabolic laboratories. Methods: We assessed the potential role of plasma untargeted metabolomics in a clinical diagnostic setting by using direct infusion high resolution mass spectrometry (DI-HRMS) in parallel with traditional targeted metabolite assays. We compared quantitative data and qualitative performance of targeted versus untargeted metabolomics in patients suspected of an IMD (n = 793 samples) referred to our laboratory for 1year. To compare results of both approaches, the untargeted data was limited to polar metabolites that were analyzed in targeted plasma assays. These include amino acid, (acyl)carnitine and creatine metabolites and are suitable for diagnosing IMDs across many of the disease groups described in the international classification of inherited metabolic disorders (ICIMD). Results: For the majority of metabolites, the concentrations as measured in targeted assays correlated strongly with the semi quantitative Z-scores determined with DI-HRMS. For 64/793 patients, targeted assays showed an abnormal metabolite profile possibly indicative of an IMD. In 55 of these patients, similar aberrations were found with DI-HRMS. The remaining 9 patients showed only marginally increased or decreased metabolite concentrations that, in retrospect, were most likely to be clinically irrelevant. Illustrating its potential, DI-HRMS detected additional patients with aberrant metabolites that were indicative of an IMD not detected by targeted plasma analysis, such as purine and pyrimidine disorders and a carnitine synthesis disorder. Conclusion: This one-year pilot study showed that DI-HRMS untargeted metabolomics can be used as a first-tier approach replacing targeted assays of amino acid, acylcarnitine and creatine metabolites with ample opportunities to expand. Using DI-HRMS untargeted metabolomics as a first-tier will open up possibilities to look for new biomarkers.

Tagged IDS causes efficient and engraftment-independent prevention of brain pathology during lentiviral gene therapy for Mucopolysaccharidosis type II

Mucopolysaccharidosis type II (OMIM 309900) is a lysosomal storage disorder caused by iduronate 2-sulfatase (IDS) deficiency and accumulation of glycosaminoglycans, leading to progressive neurodegeneration. As intravenously infused enzyme replacement therapy cannot cross the blood-brain barrier (BBB), it fails to treat brain pathology, highlighting the unmet medical need to develop alternative therapies. Here, we test modified versions of hematopoietic stem and progenitor cell (HSPC)-mediated lentiviral gene therapy (LVGT) using IDS tagging in combination with the ubiquitous MND promoter to optimize efficacy in brain and to investigate its mechanism of action. We find that IDS tagging with IGF2 or ApoE2, but not RAP12x2, improves correction of brain heparan sulfate and neuroinflammation at clinically relevant vector copy numbers. HSPC-derived cells engrafted in brain show efficiencies highest in perivascular areas, lower in choroid plexus and meninges, and lowest in parenchyma. Importantly, the efficacy of correction was independent of the number of brain-engrafted cells. These results indicate that tagged versions of IDS can outperform untagged IDS in HSPC-LVGT for the correction of brain pathology in MPS II, and they imply both cell-mediated and tag-mediated correction mechanisms, including passage across the BBB and increased uptake, highlighting their potential for clinical translation.

Phenotypic effect of GBA1 variants in individuals with and without Parkinson's disease: The RAPSODI study

BackgroundVariants in the GBA1 gene cause the lysosomal storage disorder Gaucher disease (GD). They are also risk factors for Parkinson's disease (PD), and modify the expression of the PD phenotype.The penetrance of GBA1 variants in PD is incomplete, and the ability to determine who among GBA1 variant carriers are at higher risk of developing PD, would represent an advantage for prognostic and trial design purposes. ObjectivesTo compare the motor and non-motor phenotype of GBA1 carriers and non-carriers. MethodsWe present the cross-sectional results of the baseline assessment from the RAPSODI study, an online assessment tool for PD patients and GBA1 variant carriers. The assessment includes clinically validated questionnaires, a tap-test, the University of Pennsyllvania Smell Identification Test and cognitive tests. Additional, homogeneous data from the PREDICT-PD cohort were included. ResultsA total of 379 participants completed all parts of the RAPSODI assessment (89 GBA1-negative controls, 169 GBA1-negative PD, 47 GBA1-positive PD, 47 non-affected GBA1 carriers, 27 GD). Eighty-six participants were recruited through PREDICT-PD (43 non-affected GBA1 carriers and 43 GBA1-negative controls). GBA1-positive PD patients showed worse performance in visual cognitive tasks and olfaction compared to GBA1-negative PD patients. No differences were detected between non-affected GBA1 carriers carriers and GBA1-negative controls. No phenotypic differences were observed between any of the non-PD groups. ConclusionsOur results support previous evidence that GBA1-positive PD has a specific phenotype with more severe non-motor symptoms. However, we did not reproduce previous findings of more frequent prodromal PD signs in non-affected GBA1 carriers.

Implementation and results of a risk-sharing scheme for enzyme replacement therapy in lysosomal storage diseases

ObjectiveTo describe a risk-sharing program's implementation and results on enzyme replacement therapy for lysosomal diseases. MethodThe program was designed and implemented in a referral hospital for congenital metabolic diseases. The conclusion of agreements required the following phases: 1) To define and agree on response variables and criteria to treatment; 2) to assign discount percentage to each stage of effectiveness; 3) to prepare and sign the agreement by all parties; 4) to implement the agreement; 5) to individualize purchases management; 6) to evaluate clinical results, and 7) to issue an annual report. ResultsEight patients were included in the program (four with Hurler's disease, two with Pompe and two with Gaucher), five of them were women and three were men. After analyzing the defined variables and response criteria, all patients presented full effectiveness after two or three years of follow-up except one of them that could not be evaluated. Given the effectiveness achieved, the hospital made full payment of all administered therapies. ConclusionsThe implanted risk-sharing program is Spain's first published event of paying for clinical results using orphan drugs. Economic impact has been limited, and program implementation has gone through a complex process of formulation and management. However, the greatest achievement has been to reduce the knowledge gap between efficacy and effectiveness, stating that the therapies administered have shown the optimal benefits for which the funder is willing to pay.

Palliative Care in Children with Inherited Metabolic Diseases: Why does it matter?

Inherited metabolic diseases (IMD) bring considerable burden on the child and family. Challenging areas for health care include the identification of distressing symptoms, prognostic uncertainty, and bereavement. Literature regarding the impact of paediatric palliative care (PPC) is scarce. This study aims to evaluate children with IMD referred to a PPC team (PPCT) and to analyse its impact on home care, decision to limit treatment (DLT), use of hospital resources (emergency department admissions - EDA, hospital admissions - HA, intensive care admissions - ICA) and end of life support. Retrospective cohort study of children with IMD referred to a specialized PPCT (2016-2022). We assessed clinical data: symptoms control, time of referral and length of the follow-up period, DLT, device dependency, use of hospital resources prior to and after referral, place of death and end-of-life support. Fifteen children with IMD were referred to PPCT (8% of total referrals), with median age of 7 years (4 months - 17 years); 53% female. All children were non or pre-verbal. Most prevalent symptoms were neurologic and motor impairment (100%), respiratory and gastrointestinal (75%). 80% had tube feeding, 90% had some respiratory device (non-invasive ventilation in 23%). All children had multidrug use, with a mean of 6 drugs per child (2-9). 73% had home PPC and 80% had DLT planned. Nine children died (78% in hospital), after a mean of 17 months of follow-up (2 months to 4 years), all with DLT planned. 67% had support from PPCT at the end of life. All these families received emotional support. Decrease in EDA (10 vs 2) was noticed before and after PPCT. No impact was seen in HA and ICA (6 vs 5 and 1 vs 1, respectively) and there was a longer mean of hospitalisation stay (15 vs 32 days). Our cohort includes a group of children with severe, complex and neurodegenerative IMD. They need multiple medications for symptoms control, are highly dependent on medical devices and consume significant healthcare resources. Communication impairment adds complexity being a major barrier to symptom assessment. PPCT referral allowed home support, anticipated care plans development with end of life and bereavement support, as well as a tendency towards a reduction in EDA. These findings reinforce the need for holistic approach to identify and address the PPC needs of children with IMD.

Lentiviral gene therapy with IGF2-tagged GAA normalizes the skeletal muscle proteome in murine Pompe disease

Pompe disease is a lysosomal storage disorder caused by deficiency of acid alpha-glucosidase (GAA), resulting in glycogen accumulation with profound pathology in skeletal muscle. We recently developed an optimized form of lentiviral gene therapy for Pompe disease in which a codon-optimized version of the GAA transgene (LV-GAAco) was fused to an insulin-like growth factor 2 (IGF2) peptide (LV-IGF2.GAAco), to promote cellular uptake via the cation-independent mannose-6-phosphate/IGF2 receptor. Lentiviral gene therapy with LV-IGF2.GAAco showed superior efficacy in heart, skeletal muscle, and brain of Gaa−/− mice compared to gene therapy with untagged LV-GAAco. Here, we used quantitative mass spectrometry using TMT labeling to analyze the muscle proteome and the response to gene therapy in Gaa−/− mice. We found that muscle of Gaa−/− mice displayed altered levels of proteins including those with functions in the CLEAR signaling pathway, autophagy, cytoplasmic glycogen metabolism, calcium homeostasis, redox signaling, mitochondrial function, fatty acid transport, muscle contraction, cytoskeletal organization, phagosome maturation, and inflammation. Gene therapy with LV-GAAco resulted in partial correction of the muscle proteome, while gene therapy with LV-IGF2.GAAco resulted in a near-complete restoration to wild type levels without inducing extra proteomic changes, supporting clinical development of lentiviral gene therapy for Pompe disease. SignificanceLysosomal glycogen accumulation is the primary cause of Pompe disease, and leads to a cascade of pathological events in cardiac and skeletal muscle and in the central nervous system. In this study, we identified the proteomic changes that are caused by Pompe disease in skeletal muscle of a mouse model. We showed that lentiviral gene therapy with LV-IGF2.GAAco nearly completely corrects disease-associated proteomic changes. This study supports the future clinical development of lentiviral gene therapy with LV-IGF2.GAAco as a new treatment option for Pompe disease.

Nanoreporter Identifies Lysosomal Storage Disease Lipid Accumulation Intracranially.

Dysregulated lipid metabolism contributes to neurodegenerative pathologies and neurological decline in lysosomal storage disorders as well as more common neurodegenerative diseases. Niemann-Pick type A (NPA) is a fatal neurodegenerative lysosomal storage disease characterized by abnormal sphingomyelin accumulation in the endolysosomal lumen. The ability to monitor abnormalities in lipid homeostasis intracranially could improve basic investigations and the development of effective treatment strategies. We investigated the carbon nanotube-based detection of intracranial lipid content. We found that the near-infrared emission of a carbon nanotube-based lipid sensor responds to lipid accumulation in neuronal and in vivo models of NPA. The nanosensor detected lipid accumulation intracranially in an acid sphingomyelinase knockout mouse via noninvasive near-infrared spectroscopy. This work indicates a tool to improve drug development processes in NPA, other lysosomal storage diseases, and neurodegenerative diseases.

Hypertrophic Cardiomyopathy and Ventricular Preexcitation in the Young: Cause and Accessory Pathway Characteristics.

The cause of hypertrophic cardiomyopathy (HCM) in the young is highly varied. Ventricular preexcitation (preexcitation) is well recognized, yet little is known about the specificity for any cause and the characteristics of the responsible accessory pathways (AP). Retrospective cohort study of patients <21 years of age with HCM/preexcitation from 2000 to 2022. The cause of HCM was defined as isolated HCM, storage disorder, metabolic disease, or genetic syndrome. Atrioventricular AP (true AP) were distinguished from fasciculoventricular fibers (FVF) using standard invasive electrophysiology study criteria. AP were defined as high risk if any of the following were <250 ms: shortest preexcited RR interval in atrial fibrillation, shortest paced preexcited cycle length, or anterograde AP effective refractory period. We identified 345 patients with HCM and 28 (8%) had preexcitation (isolated HCM, 10/220; storage disorder, 8/17; metabolic disease, 5/19; and genetic syndrome, 5/89). Six (21%) patients had clinical atrial fibrillation (1 with shortest preexcited RR interval <250 ms). Twenty-two patients underwent electrophysiology study which identified 23 true AP and 16 FVF. Preexcitation was exclusively FVF mediated in 8 (36%) patients. Five (23%) patients had AP with high-risk conduction properties (including ≥1 patient in each etiologic group). Multiple AP were seen in 8 (36%) and AP plus FVF in 10 (45%) patients. Ablation was acutely successful in 13 of 14 patients with recurrence in 3. One procedure was complicated by complete heart block after ablation of a high-risk midseptal AP. There were significant differences in QRS amplitude and delta wave amplitude between groups. There were no surface ECG features that differentiated AP from FVF. Young patients with HCM and preexcitation have a high likelihood of underlying storage disease or metabolic disease. Nonisolated HCM should be suspected in young patients with large QRS and delta wave amplitudes. Surface ECG is not adequate to discriminate preexcitation from a benign FVF from that secondary to potentially life-threatening AP.

Tau accumulation in degradative organelles is associated to lysosomal stress

Neurodegenerative disorders are characterized by the brain deposition of insoluble amyloidogenic proteins, such as α-synuclein or Tau, and the concomitant deterioration of cell functions such as the autophagy-lysosomal pathway (ALP). The ALP is involved in the degradation of intracellular macromolecules including protein aggregates. ALP dysfunction due to inherited defects in lysosomal or non-lysosomal proteins causes a group of diseases called lysosomal storage disorders (LSD) because of abnormal accumulation of lysosomal degradation substrates. Supporting the contribution of ALP defects in neurodegenerative diseases, deposition of amyloidogenic proteins occurs in LSD. Moreover, heterozygous mutations of several ALP genes represent risk factors for Parkinson’s disease. The reciprocal contribution of α-synuclein accumulation and lysosomal dysfunction have been extensively studied. However, whether this adverse crosstalk also embraces Tau pathology needs more investigation. Here, we show in human primary fibroblasts that Tau seeds isolated from the brain of Alzheimer’s disease induce Tau accumulation in acidic degradative organelles and lysosomal stress. Furthermore, inhibition of glucocerebrosidase, a lysosomal enzyme mutated in Gaucher’s disease and a main risk for Parkinson’s disease, causes lysosomal dysfunction in primary fibroblasts and contributes to the accumulation of Tau. Considering the presence of Tau lesions in Parkinson’s disease as well as in multiple neurodegenerative disorders including Alzheimer’s disease, our data call for further studies on strategies to alleviate ALP dysfunction as new therapeutic opportunity for neurodegenerative diseases and LSD.

Tetrahydrocannabinol in Pediatrics: Room for Improvement?

Introduction: The use of medical cannabis in pediatrics is not common in clinical practice, and there is a lack of prospective studies, especially in pediatric subpopulations. This study aimed to provide data on the off-label administration of tetrahydrocannabinol (∆9-THC) in a pediatric tertiary center in Austria. Methods: A retrospective data analysis was performed to assess the use of ∆9-THC at the Department of Pediatrics and Adolescent Medicine at the Comprehensive Center of Pediatrics (Medical University Vienna) from 2016 to 2018. The use of ∆9-THC in the Pediatric Department at the Medical University Vienna between 2016 and 2018 was analyzed using a retrospective design. Results: The most common diagnoses of patients receiving ∆9-THC were brain cancer and genetic diseases, including inborn metabolic disorders. The 32 patients who had received ∆9-THC had an arithmetic mean of 9.42 diagnoses and were treated with an arithmetic mean of 13.52 other drugs. Eleven of the 32 patients died by the end of the study period, indicating palliative use. Conclusion: The data shows that only severely ill patients were treated with ∆9-THC. A lack of information on the drug’s indications, duration, and dosage was noticed in the files, which could represent problems for patient safety.

The diagnostic journey for patients with late-onset GM2 Gangliosidoses

Late-onset forms of GM2 gangliosidosis―mainly, Tay-Sachs disease and Sandhoff disease―are under-recognized in clinical practice. In these rare lysosomal storage disorders, deficiency of β-hexosaminidase A results in excessive accumulation of GM2 ganglioside primarily within neurons, leading to cell death and progressive neurodegenerative symptoms, including ataxia, dysarthria, muscle weakness, tremors, atrophy, and psychosis. Presentation is variable and often mimics more common neurodegenerative disorders. We conducted semi-structured interviews on GM2 gangliosidoses diagnosis and treatment with five experts, 30 neurologists, and 28 patients and caregivers. Symptom onset occurred during adolescence/early adulthood in 92% of patients (median age: 14 years). Patients first visited a healthcare provider at a median age of 20 years and received a GM2 diagnosis at a median age of 26 years. Nearly all patients reported problems with their legs and balance starting from symptom onset. Problems with memory, attention span, speech and fatigue were reported more after diagnosis. Patients visited an average of eight healthcare providers before receiving a diagnosis; 64% were diagnosed by a neurologist. Four neurologists (13%) in our sample were aware that there are late-onset forms of GM2 gangliosidosis. The path to diagnosis is long for this late-onset form of a classically fatal infantile disease.

Urinary Metabolic Distinction of Niemann-Pick Class 1 Disease through the Use of Subgroup Discovery.

In this investigation, we outline the applications of a data mining technique known as Subgroup Discovery (SD) to the analysis of a sample size-limited metabolomics-based dataset. The SD technique utilized a supervised learning strategy, which lies midway between classificational and descriptive criteria, in which given the descriptive property of a dataset (i.e., the response target variable of interest), the primary objective was to discover subgroups with behaviours that are distinguishable from those of the complete set (albeit with a differential statistical distribution). These approaches have, for the first time, been successfully employed for the analysis of aromatic metabolite patterns within an NMR-based urinary dataset collected from a small cohort of patients with the lysosomal storage disorder Niemann-Pick class 1 (NPC1) disease (n = 12) and utilized to distinguish these from a larger number of heterozygous (parental) control participants. These subgroup discovery strategies discovered two different NPC1 disease-specific metabolically sequential rules which permitted the reliable identification of NPC1 patients; the first of these involved 'normal' (intermediate) urinary concentrations of xanthurenate, 4-aminobenzoate, hippurate and quinaldate, and disease-downregulated levels of nicotinate and trigonelline, whereas the second comprised 'normal' 4-aminobenzoate, indoxyl sulphate, hippurate, 3-methylhistidine and quinaldate concentrations, and again downregulated nicotinate and trigonelline levels. Correspondingly, a series of five subgroup rules were generated for the heterozygous carrier control group, and 'biomarkers' featured in these included low histidine, 1-methylnicotinamide and 4-aminobenzoate concentrations, together with 'normal' levels of hippurate, hypoxanthine, quinolinate and hypoxanthine. These significant disease group-specific rules were consistent with imbalances in the combined tryptophan-nicotinamide, tryptophan, kynurenine and tyrosine metabolic pathways, along with dysregulations in those featuring histidine, 3-methylhistidine and 4-hydroxybenzoate. In principle, the novel subgroup discovery approach employed here should also be readily applicable to solving metabolomics-type problems of this nature which feature rare disease classification groupings with only limited patient participant and sample sizes available.

A Delphi Survey Study to Formulate Statements on the Treatability of Inherited Metabolic Disorders to Decide on Eligibility for Newborn Screening.

The Wilson and Jungner (W&J) and Andermann criteria are meant to help select diseases eligible for population-based screening. With the introduction of next-generation sequencing (NGS) methods for newborn screening (NBS), more inherited metabolic diseases (IMDs) can technically be included, and a revision of the criteria was attempted. This study aimed to formulate statements and investigate whether those statements could elaborate on the criterion of treatability for IMDs to decide on eligibility for NBS. An online Delphi study was started among a panel of Dutch IMD experts (EPs). EPs evaluated, amended, and approved statements on treatability that were subsequently applied to 10 IMDs. After two rounds of Delphi, consensus was reached on 10 statements. Application of these statements selected 5 out of 10 IMDs proposed for this study as eligible for NBS, including 3 IMDs in the current Dutch NBS. The statement: 'The expected benefit/burden ratio of early treatment is positive and results in a significant health outcome' contributed most to decision-making. Our Delphi study resulted in 10 statements that can help to decide on eligibility for inclusion in NBS based on treatability, also showing that other criteria could be handled in a comparable way. Validation of the statements is required before these can be applied as guidance to authorities.

Two fluorimetric determinations of acid α-glucosidase activity in dried blood spot: Pompe disease in Iranian population

IntroductionPompe disease is a lysosomal storage disorder. This study aimed to validate and compare 2 fluorimetric methods for measuring α-glucosidase acid activity in dried blood spot sample (DBS), with potential applications in neonatal screening, and disease follow-up of Pompe patients among the Iranian population for the first time. Materials and methodsThe evaluation involved 3 enzyme levels and 7 parameters. The analysis included 141 Healthy individuals, 8 Pompe patients, and 10 obligate heterozygotes using reference and modified methods. ResultsBoth methods exhibited highly linear calibration curves. The limit of detection (LOD) and limit of quantification (LOQ) were obtained in the micromolar concentration range in 2 methods. Inter-day and intra-day precision, expressed as relative standard deviations (RSD%) were calculated. The normal ranges were determined in healthy individuals. Receiver operating characteristic (ROC) curves were analyzed, and 2 parameters, total neutral α-glucosidase (NAG)/acid α-glucosidase (GAA) and pH ratio, were identified as cut-off values with excellent accuracy, sensitivity, and specificity for evaluating Pompe disease in both methods. ConclusionsEstablishing and implementing these 2 methods for the Iranian population effectively differentiated between healthy and patient individuals. Method II, with its shorter incubation time, demonstrated practicality in the clinical setting.

Prevalence of myocarditis and its contribution to the course of primary myocardial hypertrophy

Aim. To assess the incidence of myocarditis in patients with primary myocardial hypertrophy and to study its contribution to the disease course.Material and methods. The study included 100 patients with primary left ventricular myocardial hypertrophy, 52 men and 48 women (mean age, 51,5±15,7 years; followup period 10,4 [2,1; 36,1] months). All patients underwent electrocardiography, 24-hour electrocardiographic monitoring, echocardiography, as well as DNA analysis (n=96), myocardium pathological study (n=29), cardiac magnetic resonance imaging (n=31), cardiac multislice computed tomography (n=26), assessment of anti-cardiac antibodies (n=43), free light chain level in serum and urine by immunofixation method (n=10); 99mTc-pyrophosphate myocardial scintigraphy (n=5); biopsy of the rectal mucosa and/or subcutaneous fat for amyloid (n=9).Results. In 68%, true (sarcomeric) hypertrophic cardiomyopathy (HCM) was diagnosed, in 16% — amyloidosis with cardiac involvement, in 10% — storage diseases, in 3% — neuromuscular diseases, in 2% — myocardial hypertrophy was combined with severe restriction (mixed phenotype), and in 1% — LEOPARD syndrome. Concomitant myocarditis was diagnosed in 30% of patients. In HCM, myocarditis was detected in 31% of cases. These patients had a significantly higher heart failure class (heart failure class 3 [2; 3] vs 2 [1; 3], p=0,026) and mortality (33,3% vs 6,4%, p=0,01). In amyloidosis, the incidence of myocarditis was 31,3%. In these patients, ventricular tachycardia was observed significantly more often: 80,0% vs 18,2% (p=0,036). The prevalence of concomitant myocarditis in the subgroup of storage diseases was 30%: 2 patients with Fabry disease and 1 patient with Danon disease. Of the three patients with neuromuscular diseases, myocarditis was diagnosed in 1. In the subgroups with the restrictive phenotype and LEOPARD syndrome, no cases of myocarditis were recorded. Treatment of myocarditis made it possible to stabilize the patients' condition.Conclusion. Concomitant myocarditis led to heart failure progression, worsening ventricular arrhythmias and, as a consequence, an increased risk of sudden cardiac death. It is necessary to actively diagnose and treat myocarditis in patients with primary myocardial hypertrophy.

THU468 Finding An Effective Treatment For Osteoporosis In Gaucher Disease

Abstract Disclosure: C. Lesniak: None. M.S. Akula: None. Background: Gaucher disease is a rare autosomal recessive disorder, leading to a deficiency of the enzyme glucocerebrosidase and accumulation of lipid-laden macrophages and dysfunction of multiple organs. The skeletal system is commonly affected resulting in reduced bone mineral density (BMD), marrow infiltration and bone infarction. Enzyme replacement therapy (ERT) has been a mainstay of treatment, and bisphosphonate therapy has been used to help treat osteoporosis, but newer agents are not well studied in this population. Case Description: The patient is a 62 year old female with a history of Gaucher disease Type 1 (GD1) and osteoporosis, treated with alendronate. She was diagnosed with GD1 in childhood and treated with glucocerebrosidase as ERT. She was diagnosed with osteoporosis in 2018 and started on bisphosphonates after a DXA scan showed a T-score at the lumbar spine of −3.2 and -1.4 at the left hip. She denied bone or back pain and has no history of any osteolytic lesions or osteonecrosis. Workup for secondary causes of osteoporosis was negative. She was taking alendronate 70 mg weekly, calcium 1800 mg daily, and vitamin D 4000 IU daily. Labs showed calcium 9.1 mg/dL, TSH 1.530 uIU/mL, PTH 34 pg/mL, and 25-hydroxy vitamin D 38.7 ng/mL. Repeat DXA scan showed worsening osteoporosis with a T-score at the lumbar spine of −3.4 and left hip of −2.5. As her BMD worsened while on alendronate for 3 years, teriparatide was offered as an alternative treatment. Discussion: Gaucher disease is a rare lysosomal storage disorder affecting multiple organs. Up to 90% of patients with GD1 have bone involvement of some kind. DXA scan should be done soon after diagnosis. Reduced BMD in GD1 is common and is associated with increased fracture risk. ERT has been the main management option to treat bone manifestations with improvement in BMD shown after 3-5 years. After 8 years of treatment with ERT, patients have been shown to reach the BMD of the age and sex matched population. In addition to ERT, calcium and vitamin D3 are recommended to increase BMD. There is no standard of treatment for osteoporosis in Gaucher patients, although bisphosphonates have been shown to improve BMD. Had our patient had early DXA scans, treatment may have been initiated sooner. A single case report showed improvement in BMD with the use of teriparatide after bisphosphonate failure. The efficacy of alternative agents, such as teriparatide and romosumab, in treating osteoporosis in patients with Gaucher disease needs to be further investigated. Presentation: Thursday, June 15, 2023

SAT172 Unmasking A Pediatric Disease In Adult, A Belated Diagnosis

Abstract Disclosure: H. Syed: None. P. Au: None. M.J. Gardner: None. Background: Glycogen storage diseases (GSD) are a rare group of diseases that change the way the body uses and stores glycogen. They are usually diagnosed in the pediatric population. Hypoglycemia can be a sign. Clinical Case: A 32 year old female presented with worsening and more frequent episodes of hypoglycemia. She had no history of diabetes and was not on any hypoglycemic agents. She had been having episodes of spontaneous hypoglycemia since childhood and would get symptomatic as well. No comprehensive workup had been done prior. The episodes were becoming more frequent. A blinded continuous glucose monitor was placed on the patient to monitor her glucose levels. Results indeed showed few episodes of hypoglycemia with glucose levels in the 40s. Interestingly, she also had postprandial hyperglycemia with glucose level above 180 following an episode of hypoglycemia. She underwent a 72 hour fast in the hospital and became hypoglycemic within 24 hours with a low blood glucose of 55, consistent with hypoglycemia, and she was also symptomatic as well. At the same time, her beta hydroxybutyrate increased to 3.91 mmol/L, consistent with ketosis. Her insulin level and C-peptide level at the time of hypoglycemia were 4.35 mcunit/mL and 0.239 nmol/L, respectively, and thus insulinoma was ruled out. She next underwent a mixed meal study during which her postprandial blood glucose increased to at least 198 indicating postprandial hyperglycemia. At the same time, patient's postprandial lactate also elevated to 4 mmol/L, consistent with lactic acidosis. Her symptoms of hypoglycemia resolved once her blood sugar (BG) improved. She met criteria for Whipple’s triad. She also had had an 8 am cortisol of 13.06 mcg/dL and had an appropriate response to the ACTH stimulation test with a 60 minute post cortisol above 20 mcg/dL, thus ruling out adrenal insufficiency as a cause of hypoglycemia. These findings of the 72 hour fast that resulted in hypoglycemia, followed by postprandial hyperglycemia with lactic acidosis are consistent with Glycogen Storage Disorder Type 0. Treatment involves intake of uncooked cornstarch with protein. Patient incorporated both uncooked cornstarch along with increasing amount of protein in her diet and started using a continuous glucose monitor with alarm to monitor her BGs. As a result her episodes of frequent hypoglycemia improved. Conclusion: This case illustrates a rare case of hypoglycemia in an adult that was not thoroughly investigated when she was in her childhood and adolescence. This case teaches the importance of being familiar with pediatric conditions since it is possible that pediatric conditions, especially if they are missed by providers and not appropriately diagnosed. Presentation: Saturday, June 17, 2023

Follow-up of pre-motor symptoms of Parkinson’s disease in adult patients with Gaucher disease type 1 and analysis of their lysosomal enzyme profiles in the CSF

BackgroundParkinson’s disease (PD) is the second most common neurodegenerative disease worldwide. Its classic motor symptoms may be preceded by non-motor symptoms (NMS). Population studies have identified GBA variants as risk factors for idiopathic PD. The increased risk of PD has also been suggested in other Lysosomal Storage Disorders (LSDs). Objective: To assess the evolution of the prevalence of NMS compatible with PD in a cohort of South Brazilian adult patients with Gaucher Disease (GD) type 1, already evaluated 3 years ago (2018). Cerebrospinal Fluid (CSF) was collected to assess the levels of LSD enzymes (beta-hexosaminidases, beta-glucuronidase) and biomarker of macrophage activation (chitotriosidase, ChT), compared to controls (metachromatic leukodystrophy, MLD). Cognition was evaluated by the Montreal Cognitive Assessment (MoCA) questionnaire, daytime sleepiness by the Epworth Sleepiness Scale (ESS), depression by Beck´s Inventory, constipation by the Unified Multiple System Atrophy Rating Scale (UMSARS) scale, and REM sleep behavior disorder by the single-question screen. Hyposmia was assessed with Sniffin’ Sticks (SST).ResultsNineteen patients completed the follow-up (mean age of the sample was 44 years; range, 26–71). The patient with the highest number of NMS at the baseline (4 including the lowest SST score) was diagnosed with PD four years later. Apart from an improvement in the ESS score, no other statistical significance was found between the number of NMS between the first and second evaluation, nor between patients with one L444P variant (n = 5) and the rest of the cohort. CSF was collected in five patients (mean age of the sample was 40 years, range 30–53. A significant difference was found in the mean CSF activity levels of beta-hexosaminidases and beta-glucuronidase between GD1 and MLD patients. Mean ChT (CSF) was 62 nmol/h/mL in GD patients and 142 in MLD (n = 6) patients.ConclusionsThe patient with the highest number of NMS in our 2018 cohort was the one that developed PD, corroborating with the importance of this longitudinal follow-up. CSF and plasma analysis might allow a better understanding of the neurodegenerative processes connecting PD and the lysosomal environment. Further analysis is needed to understand this relationship.