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One-year results of the placebo-controlled ASCEND trial of olipudase alfa enzyme replacement therapy in adults with chronic acid sphingomyelinase deficiency

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... Two separate clinical studies evaluating olipudase alfa for the treatment of chronic ASMD in adult and paediatric patients have also demonstrated positive results [27,31]. The Phase I/II open label, ascending dose, multicentre ASCEND-Peds study (NCT02292654) evaluated the safety, tolerability, and pharmacokinetics of olipudase alfa in 20 paediatric patients with chronic visceral ASMD over a 64-week study period [27]. ...
... Most AEs were mild to moderate in severity, and no permanent treatment discontinuations were reported. The ongoing Phase II/III randomised, double-blind, placebo-controlled ASCEND (adults) study (NCT02004691) evaluated the efficacy, safety, and pharmacokinetics/pharmacodynamics of olipudase alfa in 36 adults with chronic visceral ASMD over a 52-week primary analysis period, which is now being followed by an extension period (all treated patients) of up to 4 years [31]. Patients received either olipudase alfa intravenous infusion or placebo every two weeks at an escalating dose from 0.1 mg/kg up to 3 mg/kg administered every two weeks. ...
... Similarly, in 2016, olipudase alfa has gained orphan designation and 'PRIority Medicines' (PRIME) designation by the European Medicines Agency, along with being awarded the SAKIGAKE designation in Japan, in order to expedite the regulatory process [33]. [31]. The aim of the dose-escalation process of olipudase alfa is gradual sphingomyelin debulking to prevent high ceramide release. ...
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Acid sphingomyelinase deficiency (ASMD) is a rare inherited lipid storage disorder caused by a deficiency in lysosomal enzyme acid sphingomyelinase which results in the accumulation of sphingomyelin, predominantly within cells of the reticuloendothelial system located in numerous organs, such as the liver, spleen, lungs, and central nervous system. Although all patients with ASMD share the same basic metabolic defect, a wide spectrum of clinical presentations and outcomes are observed, contributing to treatment challenges. While infantile neurovisceral ASMD (also known as Niemann–Pick disease type A) is rapidly progressive and fatal in early childhood, and the more slowly progressive chronic neurovisceral (type A/B) and chronic visceral (type B) forms have varying clinical phenotypes and life expectancy. The prognosis of visceral ASMD is mainly determined by the association of hepatosplenomegaly with secondary thrombocytopenia and lung disease. Early diagnosis and appropriate management are essential to reduce the risk of complications and mortality. The accessibility of the new enzyme replacement therapy olipudase alfa, a recombinant human ASM, has been expedited for clinical use based on positive clinical data in children and adult patients, such as improved respiratory status and reduced spleen volume. The aim of this article is to share the authors experience on monitoring ASMD patients and stratifying the severity of the disease to aid in care decisions.
... Besides, the spleen size decreased by 39.5% at the end of the study, compared with a 0.5% increase in the placebo arm. ERT showed an acceptable safety profile, with only five patients experiencing severe adverse events that were not treatment-related, and none of the patients discontinued treatment (81). ...
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Acid sphingomyelinase deficiency (ASMD) is an autosomal-recessive progressive multiorgan metabolic disorder due to pathogenic variants in the sphingomyelin phosphodiesterase 1 (SMPD1) gene. It can lead to death in early childhood in its most severe form. According to previous registries, the birth prevalence of ASMD is nearly 0.4–0.6 per 100,000 live births. The diagnosis of ASMD is usually delayed or missed due to the wide variability of clinical manifestations of the disease. Until recently, the management of ASMD patients was based on symptomatic treatments and supportive care; however, the introduction of enzyme replacement therapy (ERT) has revolutionized the management landscape of ASMD. ERT with a recombinant human Acid Sphingomyelinase Enzyme (ASM) administered intravenously demonstrated a significant improvement in the non-neuronopathic type of ASMD in phase 2/3 trials. In June 2022, the European Medical Agency granted the ERT, olipudase alfa, marketing authorization. The prevalence of inherited metabolic disorders, including lysosomal storage diseases (LSDs), is relatively higher in the Arab world than in the rest of the world due to the high consanguinity rate. In this study, we aim to review the current landscape of ASMD in the Gulf Cooperation Council (GCC) countries and gather insights from experts regarding the roadmap to diagnosis, prevalence, and management approaches of ASMD in the region.
... 3,4 Last, although authors are correct that there is currently no approved treatment for ASMD, the enzyme replacement therapy olipudase alfa (recombinant human acid sphingomyelinase) is in late-stage clinical development to address the non-central nervous system manifestations of ASMD. Two open-label studies of olipudase alfa, a Phase 1B trial in adults with chronic ASMD (NCT01722526) 5 and a Phase 2 trial in children with chronic ASMD (NCT02292654), 6 as well as a placebocontrolled Phase 2/3 study in 36 adults with chronic ASMD (NCT02004691) 7 have shown decreases in spleen and liver volume and improvements in dyslipidemia and pulmonary function, as well as improved growth in children. ...
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Background: Acid sphingomyelinase deficiency (ASMD) (also known as Niemann-Pick disease types A and B) is a rare and debilitating lysosomal storage disorder. This prospective, multi-center, multinational longitudinal study aimed to characterize the clinical features of chronic forms of ASMD and disease burden over time in children and adults. Results: Fifty-nine patients (31 males/28 females) ranging in age from 7 to 64 years with chronic ASMD types A/B and B and at least two disease symptoms participated from 5 countries. Disease characteristics were assessed at baseline, after 1 year, and at the final visit (ranging from 4.5 to 11 years). Thirty patients (51%) were < 18 years at baseline (median age 12 years), and 29 were adults (median age 32 years). Overall, 32/59 patients completed the final visit, 9 died, 9 discontinued, and 9 were lost to follow up. Common clinical characteristics that tended to worsen gradually with time were splenomegaly, hepatomegaly, interstitial lung disease, lung diffusion capacity (DLCO), and dyslipidemia. Spleen volumes ranged from 4 to 29 multiples of normal at baseline, and splenomegaly was moderate or severe in 86%, 83%, and 90% of individuals at baseline, year 1, and final visits, respectively. The proportion of all individuals with interstitial lung disease was 66% (39/59) at baseline and 78% (25/32) at the final visit, while median % predicted DLCO decreased by > 10% from baseline to the final visit. Nine patients died (15%), eight of causes related to ASMD (most commonly pneumonia); of these eight patients, five (63%) had symptom onset at or before age 2. Overall, six of the nine deaths occurred before age 50 with three occurring before age 20. Individuals with either severe splenomegaly or prior splenectomy were ten times more likely to have died during the follow-up period than those with smaller or intact spleens (odds ratio 10.29, 95% CI 1.7, 62.7). Most children had growth deficits that persisted into adulthood. Conclusions: This study provides important information about the natural history of chronic ASMD and provides a longitudinal view of the spectrum of disease manifestations and major morbidities in children and adults and supports the selection of clinically meaningful endpoints in therapeutic trials.
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Purpose To assess olipudase alfa enzyme replacement therapy for non–central nervous system manifestations of acid sphingomyelinase deficiency (ASMD) in children. Methods This phase 1/2, international, multicenter, open-label trial (ASCEND-Peds/NCT02292654) administered intravenous olipudase alfa every 2 weeks with intrapatient dose escalation to 3 mg/kg. Primary outcome was safety through week 64. Secondary outcomes included pharmacokinetics, spleen and liver volumes, lung diffusing capacity (DL CO ), lipid profiles, and height through week 52. Results Twenty patients were enrolled: four adolescents (12–17 years), nine children (6–11 years), and seven infants/early child (1–5 years). Most adverse events were mild or moderate, including infusion-associated reactions (primarily urticaria, pyrexia, and/or vomiting) in 11 patients. Three patients had serious treatment-related events: one with transient asymptomatic alanine aminotransferase increases, another with urticaria and rash (antidrug antibody positive [ADA+]), and a third with an anaphylactic reaction (ADA+) who underwent desensitization and reached the 3 mg/kg maintenance dose. Mean splenomegaly and hepatomegaly improved by >40% ( p < 0.0001). Mean % predicted DL CO improved by 32.9% ( p = 0.0053) in patients able to perform the test. Lipid profiles and elevated liver transaminase levels normalized. Mean height Z -scores improved by 0.56 ( p < 0.0001). Conclusion In this study in children with chronic ASMD, olipudase alfa was generally well-tolerated with significant, comprehensive improvements in disease pathology across a range of clinically relevant endpoints.
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Background Enzyme replacement therapy (ERT) with olipudase alfa, a recombinant human acid sphingomyelinase (rhASM), is being developed to treat patients with ASM deficiency (ASMD), commonly known as Niemann–Pick disease (NPD) types A or B. This study assessed the effect of ERT on lipid parameters and inflammatory markers. Methods Serum and plasma samples from five adults with NPD type B (NPD-B) who received olipudase alfa ERT for 26 weeks were analysed. We also collected fasting blood samples from fifteen age- and sex-matched participants as reference and comparison group. We measured fasting lipid profile, apolipoproteins B48 and B100 (apoB48 and apoB100), apolipoprotein A1 (apoA1), proprotein convertase subtilisin/klexin type 9 ( PCSK9) mass, oxidised low-density lipoprotein (oxLDL), small dense low-density lipoprotein cholesterol (sdLDL-C) and tumour necrosis factor α (TNF-α). Results Patients with NPD-B, compared with age and sex matched reference group, had higher triglycerides, PCSK9, apoB48, oxLDL and TNF-α and lower high density lipoprotein cholesterol (HDL-C) and apoA1. Treatment with ERT was associated with improved lipid parameters including total cholesterol, triglycerides, low density lipoprotein cholesterol (LDL-C), sdLDL-C, oxLDL and apoB100. Though there was an increase in apoA1, HDL-C was slightly reduced. TNF-α showed a reduction. ApoB100 decreased in parallel with a decrease in total serum PCSK9 mass after ERT. Conclusion This study demonstrated that patients with NPD-B had a proatherogenic lipid profile and higher circulating TNF-α compared to reference group. There was an improvement in dyslipidaemia after olipudase alfa. It was possible that reductions in LDL-C and apoB100 were driven by reductions in TNF-α and PCSK9 following ERT.
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Acid sphingomyelinase deficiency (ASMD; also known as Niemann-Pick Disease [NPD] A and B) is a rare lysosomal storage disease characterized by the pathological accumulation of sphingomyelin within multiple cell types throughout the body. The infantile neurovisceral (ASMD type A, also known as Niemann-Pick Disease type A) form of the disease is characterized by markedly low or absent enzyme levels resulting in both visceral and severe neurodegenerative involvement with death in early childhood. We report here the clinical course and autopsy findings in the case of a 3 year old male patient with infantile neurovisceral ASMD. A comprehensive examination of the autopsy tissue was conducted, including routine paraffin processing and staining, high resolution light microscopy and staining for sphingomyelin, and ultrastructural examination by electron microscopy. Profound sphingomyelin accumulation was present in virtually every organ and cell type. We report the clinicopathologic correlations of these findings and discuss the relevance of these results to the clinical practice of physicians following all patients with ASMD. This case represents one of the most extensive and detailed examinations of ASMD type A to date.
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Available from: https://www.ncbi.nlm.nih.gov/books/NBK556149/ Pulmonary function tests are performed to assess lung function. Spirometry is the most common and widely used lung function test among all followed by diffusing capacity of the lungs for carbon monoxide (DLCO). It is also known as the transfer factor.[1] DLCO is a measurement to assess the ability of the lungs to transfer gas from inspired air to the bloodstream.[2] Carbon monoxide (CO) has a high affinity for hemoglobin, and it follows the same pathway as that of oxygen to finally bind with hemoglobin. Inhaled CO is used for this test due to its high affinity for hemoglobin (200-250 times that of oxygen). Among other potential gases to be used for evaluating diffusing capacity, oxygen is not preferred since its uptake is limited by cardiac uptake and total body consumption. In brief, during a ten-second breath-hold, DLCO measures uptake of CO per unit time per mm of driving pressure of CO (cc of CO/sec/mm of Hg). The respiratory membrane forms the diffusing barrier. It separates air within the alveoli from blood flowing in the pulmonary capillaries. It consists of the following layers: Alveolar epithelium. Interstitium. Capillary endothelium. According to the Fick's equation for the diffusion of gas[3]: Vg=[k*(A)(ΔP)] / T: V = volume of gas transferred per unit time. K = diffusion coefficient of the gas. A = surface area for gas exchange. ΔP = partial pressure difference of gas. T = membrane thickness; from this law, factors that influence the movement of gas molecules across the capillary membrane are the surface area of the membrane (A), the thickness of the membrane (T), driving pressure/pressure gradient across the capillary membrane (ΔP).[4] As a consequence, the diffusion of gas across the alveolar membrane increases with: Increased surface area of the membrane (A) Increased alveolar pressure gradient(ΔP) Increased solubility of the gas. Decreased membrane thickness (T). On the other hand, the diffusion of gas across the alveolar membrane decreases with: Decreased surface area of the membrane (A) Decreased alveolar pressure gradient(ΔP) Decreased solubility of the gas. Increased membrane thickness (T).
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The liver is a major site of lipoprotein synthesis and metabolism. Liver manifestations of chronic visceral ASMD include hepatomegaly, fibrosis, elevated liver enzymes and a pro-atherogenic lipid profile. Measurements of sphingomyelin (SM) levels in liver biopsies and lyso-SM in plasma were used as pharmacodynamic biomarkers. Five adult patients with chronic visceral ASMD were enrolled in a 26-week phase 1b trial of enzyme replacement therapy (ERT) with olipudase alfa (NCT01722526) followed by an ongoing long-term extension study (NCT02004704). We compare the changes in hepatic SM levels, plasma lyso-SM, and lipoprotein profiles after 42 months of treatment. Progressive clearance of histologic SM storage was observed throughout the trial, along with similar reductions in plasma lyso-SM. Improvements in liver enzymes were observed at 6 months and remained stable at 42 months. Progressive reductions from baseline in pro-atherogenic lipid profiles (total cholesterol, LDL-C, VLDL-C, triglycerides) were observed at month 6 and 42. Conversely, there were progressive increases in anti-atherogenic markers, HDL-C and apolipoprotein A-I, with HDL-C increases up to 200% over baseline levels after 42 months of treatment. These data demonstrate that hepatic clearance of SM during olipudase alfa treatment over 42 months is associated with overall improvements in the lipid profiles of ASMD patients. The clinical relevance of these findings needs to be determined in the future, but we speculate that these improvements may reduce the risk for liver cirrhosis and cardiovascular disease. Trial registration: Clintrials.gov trial registration # NCT01722526
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Background Acid sphingomyelinase deficiency (ASMD) also known as Niemann-Pick disease, is a rare lysosomal storage disorder with a diverse disease spectrum that includes slowly progressive, chronic visceral (type B) and neurovisceral forms (intermediate type A/B), in addition to infantile, rapidly progressive fatal neurovisceral disease (type A). Purpose and methods We review the published evidence on the relevance of splenomegaly and reduced lung diffusion capacity to the clinical burden of chronic forms of ASMD. Targeted literature searches were conducted to identify relevant ASMD and non-ASMD studies for associations between diffusing capacity of the lungs for carbon monoxide (DLCO) and splenomegaly, with clinical parameters and outcome measures. Results Respiratory disease and organomegaly are primary and independent contributors to mortality, disease burden, and morbidity for patients with chronic ASMD. The degree of splenomegaly correlates with short stature, atherogenic lipid profile, and degree of abnormality of hematologic parameters, and thus may be considered a surrogate marker for bleeding risk, abnormal lipid profiles and possibly, liver fibrosis. Progressive lung disease is a prevalent clinical feature of chronic ASMD, contributing to a decreased quality of life (QoL) and an increased disease burden. In addition, respiratory-related complications are a major cause of mortality in ASMD. Conclusions The reviewed evidence from ASMD natural history and observational studies supports the use of lung function and spleen volume as clinically meaningful endpoints in ASMD trials that translate into important measures of disease burden for patients.
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Background Acid sphingomyelinase deficiency (ASMD), a rare lysosomal storage disease, results from mutations in SMPD1, the gene encoding acid sphingomyelinase (ASM). As a result, sphingomyelin accumulates in multiple organs including spleen, liver, lung, bone marrow, lymph nodes, and in the most severe form, in the CNS and peripheral nerves. Clinical manifestations range from rapidly progressive and fatal infantile neurovisceral disease, to less rapidly progressing chronic neurovisceral and visceral forms that are associated with significant morbidity and shorter life span due to respiratory or liver disease. Objectives To provide a contemporary guide of clinical assessments for disease monitoring and symptom management across the spectrum of ASMD phenotypes. Methods An international group of ASMD experts in various research and clinical fields used an evidence-informed consensus process to identify optimal assessments, interventions, and lifestyle modifications. Results Clinical assessment strategies for major organ system involvement, including liver, spleen, cardiovascular, pulmonary, and neurological/developmental are described, as well as symptomatic treatments, interventions, and/or life style modifications that may lessen disease impact. Conclusions There is currently no disease-specific treatment for ASMD, although enzyme replacement therapy with a recombinant human ASM (olipudase alfa) is in clinical development. Current monitoring addresses symptoms and multisystem involvement. Recommended interventions and lifestyle modifications are designed to address morbidity and disease complications and improve patient quality of life. While infantile neurovisceral ASMD is uniformly fatal in early childhood, patients with chronic visceral and chronic neurovisceral ASMD require appropriate management throughout childhood and adulthood by an interdisciplinary clinical team.
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Olipudase alfa, a recombinant human acid sphingomyelinase (ASM), is an enzyme replacement therapy for the treatment of nonneurologic manifestations of acid sphingomyelinase deficiency (ASMD). This ongoing, open-label, long-term study (NCT02004704) assessed safety and efficacy of olipudase alfa following 30 months of treatment in five adult patients with ASMD. There were no deaths, serious or severe events, or discontinuations during 30 months of treatment. The majority of adverse events were mild and included headache, nausea, and abdominal pain. No patient developed anti-drug antibodies and there were no clinically significant adverse changes in vital signs, hematology, or cardiac safety parameters. Statistically significant reductions in liver (31%) and spleen (39%) volumes were maintained through 30 months of treatment. There was a mean increase in lung diffusing capacity of 35%, and clinically relevant improvements in infiltrative lung disease parameters. Lipid profiles improved in all patients. Improvements in bone mineral density of the spine were observed in some patients. Chitotriosidase in serum and lyso-sphingomyelin in dried blood spots decreased with olipudase alfa treatment, suggesting utility as biomarkers for monitoring treatment efficacy. Olipudase alfa is the first etiology-specific treatment in development for ASMD. This study demonstrates that treatment with olipudase alfa for 30 months is well-tolerated and associated with life-transforming sustained improvements in relevant disease clinical measures. Electronic supplementary material The online version of this article (10.1007/s10545-017-0123-6) contains supplementary material, which is available to authorized users.
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Anti-drug antibodies (ADA) pose a potential risk to patient safety and efficacy and are routinely monitored during clinical trials. Pre-existing drug-reactive antibodies are present in patients without prior drug exposure and are defined by their ability to bind to a component of the drug. These pre-existing drug-reactive antibodies are frequently observed and could represent an adaptive immune response of an individual who has been previously exposed to antigens with structural similarities to the biotherapeutic. Clinical consequences of these antibodies can vary from no impact to adverse effects on patient safety, exposure, and efficacy, and are highly dependent on biotherapeutic modality, disease indications, and patient demographics. This paper describes how the immunogenicity risk assessment of a biotherapeutic integrates the existence of pre-existing drug-reactive antibodies, and provides recommendations for risk-based strategies to evaluate treatment-emergent ADA responses.
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Acid sphingomyelinase deficiency (ASMD), a rare lysosomal storage disease, is an autosomal recessive genetic disorder caused by different SMPD1 mutations. Historically, ASMD has been classified as Niemann-Pick disease (NPD) types A (NPD A) and B (NPD B). NPD A is associated with a uniformly devastating disease course, with rapidly progressing psychomotor degeneration, leading to death typically by the age of 3 years, most often from respiratory failure. In contrast, the clinical phenotype and life expectancy of patients with NPD B may vary widely. Almost all patients have hepatosplenomegaly and an atherogenic lipid profile, and most patients have interstitial lung disease with progressive impairment of pulmonary function and hematologic abnormalities including cytopenias. Other common clinical manifestations include liver dysfunction, heart disease, skeletal abnormalities and growth delays. Some patients with ASMD who survive beyond early childhood have intermediate phenotypes (variant NPD B) characterized by combinations of non-neurologic and mild to severe neurologic symptoms. The physical and psychosocial burden of illness in patients with NPD B is substantial. Common symptoms include shortness of breath, joint or limb pain, abdominal pain, bleeding and bruising. The disease often leads to chronic fatigue, limited physical or social activity and difficulties in performing daily activities or work. Many patients die before or in early adulthood, often from pneumonia/respiratory failure or liver failure. Available treatments are limited to symptom management and supportive care. An enzyme replacement therapy currently in clinical development is expected to be the first treatment addressing the underlying pathology of the disease. Early diagnosis and appropriate management are essential for reducing the risk of complications. While knowledge about ASMD is evolving, more evidence about ASMD and the natural history across the disease spectrum is needed, to improve disease recognition, timely diagnosis and appropriate disease management.
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Acid sphingomyelinase deficiency (ASMD; Niemann-Pick disease type A and B) is a lysosomal storage disorder characterized by abnormal intracellular sphingomyelin (SM) accumulation. Prominent liver involvement results in hepatomegaly, fibrosis/cirrhosis, abnormal liver chemistries, and a proatherogenic lipid profile. Olipudase alfa (recombinant human ASM) is in clinical development as an investigational enzyme replacement therapy for the non-neurological manifestations of ASMD. In a phase 1b study conducted to evaluate the safety and tolerability of within-patient dose escalation with olipudase alfa, measurement of SM levels in liver biopsies was used as a pharmacodynamic biomarker of substrate burden. Five adult patients with non neuronopathic ASMD received escalating doses of olipudase alfa every 2 weeks for 26 weeks. Liver biopsies obtained at baseline and 26 weeks after treatment were evaluated for SM storage by histomorphometric analysis, biochemistry, and electron microscopy. Biopsies were also assessed for inflammation and fibrosis, and for the association of SM levels with liver volume, liver function tests, and lipid profiles. At baseline, SM storage present in Kupffer cells and hepatocytes ranged from 9.8% to 53.8% of the microscopic field. After 26 weeks of treatment, statistically significant reductions in SM (P<0.0001) measured by morphometry were seen in 4 patients with evaluable liver biopsies. The 26-week biopsy of the fifth patient was insufficient for morphometric quantitation. Posttreatment SM levels ranged from 1.2% to 9.5% of the microscopic field, corresponding to an 84% to 92% relative reduction from baseline. Improvements in liver volume, liver function tests, and lipid profiles were also observed. This study illustrates the utility of SM assessment by liver biopsy as a pharmacodynamic biomarker of disease burden in these patients.
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Background: Acid sphingomyelinase deficiency (ASMD), [Niemann-Pick Disease Types A and B (NPD A and B)], is an inherited metabolic disorder resulting from deficiency of the lysosomal enzyme acid sphingomyelinase. Accumulation of sphingomyelin in hepatocytes, reticuloendothelial cells, and in some cases neurons, results in a progressive multisystem disease that encompasses a broad clinical spectrum of neurological and visceral involvement, including: infantile neurovisceral ASMD (NPD A) that is uniformly fatal by 3years of age; chronic neurovisceral ASMD (intermediate NPD A/B; NPD B variant) that has later symptom onset and slower neurological and visceral disease progression; and chronic visceral ASMD (NPD B) that lacks neurological symptoms but has significant disease-related morbidities in multiple organ systems. The purpose of this study was to characterize disease-related morbidities and causes of death in patients with the chronic visceral and chronic neurovisceral forms of ASMD. Methods: Data for 85 patients who had died or received liver transplant were collected by treating physicians (n=27), or abstracted from previously published case studies (n=58). Ages at symptom onset, diagnosis, and death; cause of death; organ involvement, and morbidity were analyzed. Results: Common disease-related morbidities included splenomegaly (96.6%), hepatomegaly (91.4%), liver dysfunction (82.6%), and pulmonary disease (75.0%). The overall leading causes of death were respiratory failure and liver failure (27.7% each) irrespective of age. For patients with chronic neurovisceral ASMD (31.8%), progression of neurodegenerative disease was a leading cause of death along with respiratory disease (both 23.1%) and liver disease (19.2%). Patients with chronic neurovisceral disease died at younger ages than those with chronic visceral disease (median age at death 8 vs. 23.5years). Conclusions: The analysis emphasizes that treatment goals for patients with chronic visceral and chronic neurovisceral ASMD should include reducing splenomegaly and improving liver function and respiratory status, with the ultimate goal of decreasing serious morbidity and mortality.
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Niemann–Pick disease is a rare autosomal recessive lysosomal storage disease with three subtypes. Types A and B result from a deficiency of acid sphingomyelinase activity, associated with the accumulation of lipid-laden macrophages (so-called Niemann–Pick cells) in various tissues, especially the liver and spleen. Type A is a fatal neurodegenerative disorder of infancy. Type B Niemann–Pick disease is a less severe form with milder neurological involvement, characterized by hepatosplenomegaly, hyperlipidemia, and pulmonary involvement; most patients live into adulthood. Type C Niemann–Pick disease is a complex lipid storage disorder caused by defects in cholesterol trafficking, resulting in a clinical presentation dominated by neurological involvement. Pulmonary involvement occurs in all three types of Niemann–Pick disease, but most frequently in type B. Respiratory manifestations range from a lack of symptoms to respiratory failure. Progression of respiratory disease is slow, but inexorable, due to the accumulation of Niemann–Pick cells in the alveolar septa, bronchial walls, and pleura, potentially leading to a progressively worsening restrictive pattern on pulmonary function testing. Bronchoalveolar lavage has important diagnostic value because it shows the presence of characteristic Niemann–Pick cells. Radiographic findings consist of a reticular or reticulonodular pattern and, eventually, honeycombing, involving mainly the lower lung zones. The most common changes identified by high-resolution computed tomography are ground-glass opacities, mild smooth interlobular septal thickening, and intralobular lines. The aim of this review is to describe the main clinical, imaging, and pathological aspects of Niemann–Pick disease, with a focus on pulmonary involvement.
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Ruxolitinib, a potent Janus kinase 1/2 inhibitor, resulted in rapid and durable improvements in splenomegaly and disease-related symptoms in the 2 phase 3 COMFORT studies. Additionally, ruxolitinib was associated with prolonged survival compared with placebo (COMFORT-I) and best available therapy (COMFORT-II). We present a pooled analysis of overall survival in the COMFORT studies using an intent-to-treat analysis and an analysis correcting for crossover in the control arms. Overall, 301 patients received ruxolitinib (COMFORT-I, n=155; COMFORT-II, n=146) and 227 patients received placebo (n=154) or best available therapy (n=73). After a median 3 years of follow-up, intent-to-treat analysis showed that patients who received ruxolitinib had prolonged survival compared with patients who received placebo or best available therapy (hazard ratio=0.65; 95% confidence interval, 0.46-0.90; P=.01); the crossover-corrected hazard ratio was 0.29 (95% confidence interval, 0.13-0.63). Both patients with intermediate-2 or high-risk disease showed prolonged survival, and patients with high-risk disease in the ruxolitinib group had survival similar to that of patients with intermediate-2-risk disease in the control group. The Kaplan-Meier estimate of overall survival at week 144 was 78% in the ruxolitinib arm, 61% in the intent-to-treat control arm, and 31% in the crossover-adjusted control arm. While larger spleen size at baseline was prognostic for shortened survival, reductions in spleen size with ruxolitinib treatment correlated with longer survival. These findings are consistent with previous reports and support that ruxolitinib offers a survival benefit for patients with myelofibrosis compared with conventional therapies. (ClinicalTrials.gov identifiers: COMFORT-I, NCT00952289; COMFORT-II, NCT00934544). Copyright © 2015, Ferrata Storti Foundation.
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Olipudase alfa, a recombinant human acid sphingomyelinase (rhASM), is an investigational enzyme replacement therapy (ERT) for patients with ASM deficiency [ASMD; Niemann-Pick Disease (NPD) A and B]. This open-label phase 1b study assessed the safety and tolerability of olipudase alfa using within-patient dose escalation to gradually debulk accumulated sphingomyelin and mitigate the rapid production of metabolites, which can be toxic. Secondary objectives were pharmacokinetics, pharmacodynamics, and exploratory efficacy. Five adults with nonneuronopathic ASMD (NPD B) received escalating doses (0.1 to 3.0mg/kg) of olipudase alfa intravenously every 2weeks for 26weeks. All patients successfully reached 3.0mg/kg without serious or severe adverse events. One patient repeated a dose (2.0mg/kg) and another had a temporary dose reduction (1.0 to 0.6mg/kg). Most adverse events (97%) were mild and all resolved without sequelae. The most common adverse events were headache, arthralgia, nausea and abdominal pain. Two patients experienced single acute phase reactions. No patient developed hypersensitivity or anti-olipudase alfa antibodies. The mean circulating half-life of olipudase alfa ranged from 20.9 to 23.4h across doses without accumulation. Ceramide, a sphingomyelin catabolite, rose transiently in plasma after each dose, but decreased over time. Reductions in sphingomyelin storage, spleen and liver volumes, and serum chitotriosidase activity, as well as improvements in infiltrative lung disease, lipid profiles, platelet counts, and quality of life assessments, were observed. This study provides proof-of-concept for the safety and efficacy of within-patient dose escalation of olipudase alfa in patients with nonneuronopathic ASMD. Copyright © 2015. Published by Elsevier Inc.
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Enzyme replacement therapy with olipudase alfa (recombinant human acid sphingomyelinase) is being developed for Niemann-Pick disease type B (NPD B). A single-center, open-label, nonrandomized, single-ascending-dose trial evaluated the safety of intravenous olipudase alfa (0.03-1.0 mg/kg) in 11 adults with NPD B. Patients were monitored in the hospital for 72 h after infusion and had follow-up visits on days 14 and 28. Plasma ceramide, a product of sphingomyelin catabolism by olipudase alfa, showed dose-dependent elevations by 6 h postdose, or postinfusion. No serious adverse drug reactions (ADRs) occurred during the study. Acute phase reaction-type ADRs, as evidenced by elevated inflammatory biomarkers (high-sensitivity C-reactive protein, interleukin-8, and calcitonin) and constitutional symptoms (fever, pain, nausea, and/or vomiting) emerged 12-24 h following doses ≥0.3 mg/kg olipudase alfa. Three patients experienced hyperbilirubinemia. The study was terminated after a patient dosed at 1 mg/kg exhibited severe hyperbilirubinemia; he was subsequently diagnosed with Gilbert syndrome. The maximum tolerated dose of olipudase alfa in adults with NPD B was 0.6 mg/kg. First-dose ADRs were likely induced by elevated concentrations of ceramide (or its downstream derivatives) generated by the catabolism of accumulated sphingomyelin. Within-patient dose escalation to slowly catabolize sphingomyelin stores may be a strategy to mitigate first-dose ADRs in patients with NPD B.Genet Med advance online publication 02 April 2015Genetics in Medicine (2015); doi:10.1038/gim.2015.24.
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Recombinant human acid sphingomyelinase (rhASM) is being developed as an enzyme replacement therapy for patients with acid sphingomyelinase deficiency (Niemann-Pick disease type A and B), which causes sphingomyelin to accumulate in lysosomes. In the acid sphingomyelinase knock-out (ASMKO) mouse, intravenously administered rhASM reduced tissue sphingomyelin levels in a dose-dependent manner. When rhASM was administered to normal rats, mice, and dogs, no toxicity was observed up to a dose of 30 mg/kg. However, high doses of rhASM ≥ 10 mg/kg administered to ASMKO mice resulted in unexpected toxicity characterized by cardiovascular shock, hepatic inflammation, adrenal hemorrhage, elevations in ceramide and cytokines (especially IL-6, G-CSF, and keratinocyte chemoattractant [KC]), and death. The toxicity could be completely prevented by the administration of several low doses (3 mg/kg) of rhASM prior to single or repeated high doses (≥ 20 mg/kg). These results suggest that the observed toxicity involves the rapid breakdown of large amounts of sphingomyelin into ceramide and/or other toxic downstream metabolites, which are known signaling molecules with cardiovascular and pro-inflammatory effects. Our results suggest that the nonclinical safety assessment of novel therapeutics should include the use of specific animal models of disease whenever feasible.
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Symptomatic burden in myeloproliferative neoplasms is present in most patients and compromises quality of life. We sought to validate a broadly applicable 18-item instrument (Myeloproliferative Neoplasm Symptom Assessment Form [MPN-SAF], coadministered with the Brief Fatigue Inventory) to assess symptoms of myelofibrosis, essential thrombocythemia, and polycythemia vera among prospective cohorts in the United States, Sweden, and Italy. A total of 402 MPN-SAF surveys were administered (English [25%], Italian [46%], and Swedish [28%]) in 161 patients with essential thrombocythemia, 145 patients with polycythemia vera, and 96 patients with myelofibrosis. Responses among the 3 administered languages showed great consistency after controlling for MPN subtype. Strong correlations existed between individual items and key symptomatic elements represented on both the MPN-SAF and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30. Enrolling physicians' blinded opinion of patient symptoms (6 symptoms assessed) were highly correlated with corresponding patients' responses. Serial administration of the English MPN-SAF among 53 patients showed that most MPN-SAF items are well correlated (r > 0.5, P < .001) and highly reproducible (intraclass correlation coefficient > 0.7). The MPN-SAF is a comprehensive and reliable instrument that is available in multiple languages to evaluate symptoms associated with all types of MPNs in clinical trials globally.
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The objective of this study was to characterize the clinical features of patients with Niemann-Pick disease type B and to identify efficacy end points for future clinical trials of enzyme-replacement therapy. Fifty-nine patients who had Niemann-Pick disease type B, were at least 6 years of age, and manifested at least 2 disease symptoms participated in this multicenter, multinational, cross-sectional survey study. Medical histories; physical examinations; assessments of cardiorespiratory function, clinical laboratory data, and liver and spleen volumes; radiographic evaluation of the lungs and bone age; and quality-of-life assessments were obtained during a 2- to 3-day period. Fifty-three percent of the patients were male, 92% were white, and the median age was 17.6 years. The R608del mutation accounted for 25% of all disease alleles. Most patients initially presented with splenomegaly (78%) or hepatomegaly (73%). Frequent symptoms included bleeding (49%), pulmonary infections and shortness of breath (42% each), and joint/limb pain (39%). Growth was markedly delayed during adolescence. Patients commonly had low levels of platelets and high-density lipoprotein, elevated levels of low-density lipoprotein, very-low-density lipoprotein, triglycerides, leukocyte sphingomyelin, and serum chitotriosidase, and abnormal liver function test results. Nearly all patients had documented splenomegaly and hepatomegaly and interstitial lung disease. Patients commonly showed restrictive lung disease physiology with impaired pulmonary gas exchange and decreased maximal exercise tolerance. Quality of life was only mildly decreased by standardized questionnaires. The degree of splenomegaly correlated with most aspects of disease, including hepatomegaly, growth, lipid profile, hematologic parameters, and pulmonary function. This study documents the multisystem involvement and clinical variability of Niemann-Pick B disease. Several efficacy end points were identified for future clinical treatment studies. Because of its correlation with disease severity, spleen volume may be a useful surrogate end point in treatment trials, whereas biomarkers such as chitotriosidase also may play a role in monitoring patient treatment responses.
Article
Acid Sphingomyelinase Deficiency (ASMD), or Niemann-Pick type A/B disease, is a rare lipid storage disorder leading to accumulation of sphingomyelin and its precursors primarily in macrophages. The disease has a broad phenotypic spectrum ranging from a fatal infantile form with severe neurological involvement (the infantile neurovisceral type) to a primarily visceral form with different degrees of pulmonary, liver, spleen and skeletal involvement (the chronic visceral type). With the upcoming possibility of treatment with enzyme replacement therapy, the need for biomarkers that predict or reflect disease progression has increased. Biomarkers should be validated for their use as surrogate markers of clinically relevant endpoints. In this review, clinically important endpoints as well as biochemical and imaging markers of ASMD are discussed and potential new biomarkers are identified. We suggest as the most promising biomarkers that may function as surrogate endpoints in the future: diffusion capacity measured by spirometry, spleen volume, platelet count, low-density lipoprotein cholesterol, liver fibrosis measured with a fibroscan, lysosphingomyelin and walked distance in six minutes. Currently, no biomarkers have been validated. Several plasma markers of lipid-laden cells, fibrosis or inflammation are of high potential as biomarkers and deserve further study. Based upon current guidelines for biomarkers, recommendations for the validation process are provided.
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The eponym Niemann-Pick disease (NPD) refers to a group of patients who present with varying degrees of lipid storage and foam cell infiltration in tissues, as well as overlapping clinical features including hepatosplenomegaly, pulmonary insufficiency and/or central nervous system (CNS) involvement. Due to the pioneering work of Roscoe Brady and co-workers, we now know that there are two distinct metabolic abnormalities that account for NPD. The first is due to the deficient activity of the enzyme acid sphingomyelinase (ASM; “types A & B” NPD), and the second is due to defective function in cholesterol transport (“type C” NPD). Herein only types A and B NPD will be discussed. Type A NPD patients exhibit hepatosplenomegaly in infancy and profound CNS involvement. They rarely survive beyond 2–3 years of age. Type B patients also have hepatosplenomegaly and pathologic alterations of their lungs, but there are usually no CNS signs. The age of onset and rate of disease progression varies greatly among type B patients, and they frequently live into adulthood. Intermediate patients also have been reported with mild to moderate neurological findings. All patients with types A and B NPD have mutations in the gene encoding ASM (SMPD1), and thus the disease is more accurately referred to as ASM deficiency (ASMD). Herein we will review the clinical, pathological, biochemical, and genetic findings in types A and B NPD, and emphasize the seminal contributions of Dr. Brady to this disease. We will also discuss the current status of therapy for this disorder.
Article
Purpose: The purpose of this study was to perform a systematic evaluation of morbidity and mortality in type B Niemann-Pick disease. Methods: A total of 103 patients with Niemann-Pick disease (49 males, 54 females, age range: 1-72 years) participated in natural history studies through Mount Sinai's International Center for Types A and B Niemann-Pick Disease between 1992 and 2012. Results: Serious morbidities included significant neurological, hepatic, and cardiac disease. Thirteen patients had some degree of neurological impairment. Nine patients had cirrhosis or liver failure requiring transplantation. Coronary artery and valvular heart disease were present in nine patients. Of note, only four patients were oxygen dependent, although progressive pulmonary disease is a well-described feature of Niemann-Pick disease. During the follow-up period, 18 deaths occurred. The median age of death was 15.5 years (range 1-72). Causes of death included pneumonia, liver failure, and hemorrhage. The majority of deaths (12 of 18) occurred in patients <21 years, yielding a mortality rate of 19% in the pediatric population. Conclusion: This study demonstrates that Niemann-Pick disease is a life-threatening disorder with significant morbidity and mortality, especially in the pediatric population. The information collected in this series highlights the need for safe, effective therapy for Niemann-Pick disease.
Article
Acid sphingomyelinase deficiency (ASMD) is a lysosomal storage disorder characterized by the pathologic accumulation of sphingomyelin (SM) in multiple cell types, and occurs most prominently within the liver, spleen, and lungs, leading to significant clinical disease. Seventeen ASMD patients underwent a liver biopsy during baseline screening for a phase 1 trial of recombinant human acid sphingomyelinase (rhASM) in adults with Niemann-Pick disease type B. Eleven of the 17 were enrolled in the trial and each received a single dose of rhASM and underwent a repeat liver biopsy on day 14. Biopsies were evaluated for fibrosis, SM accumulation, and macrophage infiltration by light and electron microscopy. When present, fibrosis was periportal and pericellular, predominantly surrounding affected Kupffer cells. Two baseline biopsies exhibited frank cirrhosis. SM was localized to isolated Kupffer cells in mildly affected biopsies and was present in both Kupffer cells and hepatocytes in more severely affected cases. Morphometric quantification of SM storage in liver biopsies ranged from 4% to 44% of the microscopic field. Skin biopsies were also performed at baseline and day 14 to compare the SM distribution in a peripheral tissue with that of liver. SM storage was present at lower levels in multiple cell types of the skin, including dermal fibroblasts, macrophages, vascular endothelial cells, vascular smooth muscle cells, and Schwann cells. This phase 1 trial of rhASM in adults with ASMD provided a unique opportunity for a prospective assessment of hepatic and skin pathology in this rare disease and their potential usage as pharmacodynamic biomarkers.
Article
Prediction equations for DLCO and diffusing capacity per unit of lung volume (DL/VA) were generated from 245 normal subjects (122 women and 123 men) using a standardized technique for measuring DLCO. Measurements were made at an altitude of 1,400 meters. Multiple linear regressions were made using standard and robust regression techniques. The resultant equations predicted values for DLCO and DL/VA that were higher than most previously reported values. The use of robust regressions did not add to the predictability of standard linear regressions.
Article
To characterize the lipid profiles in patients with types A and B Niemann Pick disease (NPD) and determine if lipid abnormalities are associated with evidence of early cardiovascular disease or correlate with genotype. The study was a cross-sectional analysis of 10 patients with NPD type A and 30 patients with NPD type B that was carried out in the General Clinical Research Center. For each patient, fasting lipid profile and glucose, T4, height or length, weight, resting blood pressure, and acid sphingomyelinase deficiency genotype were measured. In type B patients, electrocardiograhic-gated helical computed tomography of the heart also was obtained. Lipid abnormalities included low (<35 mg/dL) high-density lipoprotein cholesterol in 100% of patients and hypertriglyceridemia and increased low-density lipoprotein cholesterol in 62% (25/40) and 67% (27/40) of patients, respectively. Coronary artery calcium scores were positive (>1.0) in 10 of 18 type B patients studied. There was no correlation of the Delta R608 genotype with a milder phenotype for the lipid abnormalities, as has been observed for a number of other NPD manifestations. Lipid abnormalities are part of the phenotype in types A and B NPD and may be associated with early atherosclerotic heart disease.
Article
Gaucher disease, the most common lysosomal storage disorder, is a heterogeneous multisystem condition. Patients with non-neuronopathic (type 1) Gaucher disease may suffer from hepatomegaly, splenomegaly, thrombocytopenia, bleeding tendencies, anemia, hypermetabolism, skeletal pathology, growth retardation, pulmonary disease, and decreased quality of life. Enzyme replacement therapy (ERT) with mannose-terminated glucocerebrosidase reverses or ameliorates many of the manifestations of type 1 Gaucher disease. However, the variable disease pattern and severity, and the uncertain manner of progression, render the decision to initiate ERT difficult. Thus, implementation of treatment and evaluation of the therapeutic response must be tailored to the individual patient. To obtain an evidence-based consensus on contemporary therapeutic goals, an international panel of physicians with extensive clinical experience in Gaucher disease met to review the extant literature on its treatment. The panel adopted an integrated system-based approach to arrive at a comprehensive guide to individualized management. Here we establish goals of treatment in Gaucher disease and propose a comprehensive schedule of monitoring of all relevant aspects to confirm the achievement, maintenance, and continuity of the therapeutic response.
Article
Type B Niemann-Pick disease (NPD-B) caused by acid sphingomyelinase deficiency is a rare, autosomal recessive, lysosomal storage disorder with a broad range of disease severity. The objectives of this study were to document the natural history of the disease in a large, clinically heterogeneous patient population that was followed for a period of 10 years and to determine how genotype influences phenotype. Twenty-nine patients with NPD-B had serial evaluations at least 9 months apart. Organ volumes, hematologic indices, lipid concentrations, pulmonary function, and hepatic activity were studied, and individual phenotypic severity was compared with genotype. All patients with intact spleens had splenomegaly (mean value: 12.7 multiples of normal [MN]; range: 4.5-27.3 MN), and all but 1 had hepatomegaly (mean volume: 1.91 MN; range: 0.93-3.21 MN). At initial visit, 39% had thrombocytopenia and 3% had leukopenia. At final visit, the percentages increased to 54% and 34%, respectively. Mean annual decreases in platelet count and leukocyte count were 7 x 10(3) and 0.2 x 10(3) per mm3, respectively. The typical atherogenic lipid profile was worse in older patients. A total of 69% of patients had low diffusion capacity for carbon monoxide, and more than one third had low forced expiratory volume in 1 second, forced vital capacity, and forced expiratory volume in 1 second/forced vital capacity at initial visit. All measurements of pulmonary function showed a gradual deterioration over time. Liver dysfunction was characterized by stable elevation of hepatic transaminases and bilirubin. Homozygotes for DeltaR608, P323A, and P330R had milder disease than patients with all other genotypes. The natural history of NPD-B is characterized by hepatosplenomegaly with progressive hypersplenism, worsening atherogenic lipid profile, gradual deterioration in pulmonary function, and stable liver dysfunction.
Article
Macrophage-related pulmonary diseases are a heterogeneous group of disorders characterized by macrophage accumulation, activation or dysfunction. These conditions include smoking-related interstitial lung diseases, metabolic disorders such as Niemann-Pick or Gaucher disease, and rare primary lung tumors. High-resolution computed tomography abnormalities include pulmonary ground-glass opacification secondary to infiltration by macrophages, centrilobular nodules or interlobular septal thickening reflecting peribronchiolar or septal macrophage accumulation, respectively, emphysema caused by macrophage dysfunction, and honeycombing following macrophage-related lung matrix remodeling.
Article
To evaluate findings at radiography, computed tomography (CT), and pulmonary function testing in patients with type B Niemann-Pick disease. The study was approved by the institutional review board or ethics committee at each study site and was compliant with HIPAA at the U.S. site. Written informed consent was obtained from each patient or guardian and minor assent was obtained from all children before any study-related procedures. Pulmonary involvement in 53 patients (27 male and 26 female patients; age range, 7-65 years; mean age, 23.3 years) with type B Niemann-Pick disease was evaluated with imaging and pulmonary function tests. All patients underwent chest radiography and thin-section CT, and images were independently interpreted by one of two radiologists. Spirometry (forced vital capacity [FVC] and forced expiratory volume in 1 second [FEV1]) was performed and diffusing capacity of lung for carbon monoxide (Dlco) was evaluated in all patients who could comply. A score for the degree of interstitial lung disease was derived at both radiography and CT, and the CT scores were then compared with results of pulmonary function testing and patient age by means of linear regression. CT scores were compared between the upper and lower lung zones by using the Wilcoxon signed rank test. Chest radiography and CT, respectively, revealed interstitial lung disease in 47 (90%) and 51 (98%) of the 52 patients who completed both imaging examinations. There was a basilar predominance of interstitial lung disease at CT. Six patients had pulmonary nodules, one of which was calcified at chest radiography. There were no statistically significant correlations between interstitial lung disease score at CT and age or percentage predicted FVC, FEV1, or Dlco values. Although pulmonary function test indexes may be abnormal, imaging findings do not necessarily correlate with pulmonary function in patients with type B Niemann-Pick disease.
Article
To document the prevalence of neurologic disease in Niemann-Pick disease (NPD) NPD-B. Sixty-four patients with NPD-B had detailed neurologic and ophthalmologic evaluations. The presence of neurologic abnormalities was compared with genotype. Nineteen of 64 patients (30%) had neurologic abnormalities, which were minor and nonprogressive in 14 (22%), and global and progressive in 5 (8%). In these five patients, the onset of neurologic difficulties occurred between 2 and 7 years of age and was associated with peripheral neuropathy, retinal abnormalities, and the Q292K mutation. No patients with at least one copy of DeltaR608 had neurologic involvement. The majority of patients with NPD-B have no neurologic abnormalities. In patients with neurologic abnormalities, the findings can be minor and static or severe and progressive. The latter phenotype follows a course distinct from that of classic NPD-A and is associated with the Q292K mutation and characteristic retinal findings. Thus, similar to other lysosomal storage disorders, there is a broad spectrum of neurologic abnormalities in acid sphingomyelinase deficiency, which makes the current classification scheme inaccurate.
Using and interpreting carbon monoxide diffusing capacity (DLco) correctly
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Hypersplenism: history and current status
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