Homozygous pArg610del Mutation Unusually Associated With Severe Delay of Growth in 2 Acid Sphingomyelinase Deficiency-affected Sibs.

BACKGROUND: Typically, patients with Acid Sphingomyelinase Deficiency (ASMD) because of p.Arg610del mutation, have mild phenotype with normal linear growth. OBSERVATION: We reported the case of 2 Tunisian brothers who have been referred for splenomegaly, polyadenopathies, pubertal, and growth delay. Molecular testing of SMPD1 gene revealed the presence of a homozygous p.Arg610del mutation. Lysosphingomyelin and its isoform-509 were both increased confirming ASMD for both cases. Growth hormone deficiency was highly suspected but growth hormone response after stimulating tests was acceptable for both patients. CONCLUSIONS: There is no correlation between phenotype-genotype in case of p.Arg610del mutation that could be associated to a severe delay of growth.

Cognition and anatomy of adult Niemann-Pick disease type C: Insights for the Alzheimer field.

Niemann-Pick disease type C (NPC) is a rare lysosomal storage disorder causing an intracellular lipid trafficking defect and varying damage to the spleen, liver, and central nervous system. The adult form, representing approximately 20% of the cases, is associated with progressive cognitive decline. Intriguingly, brains of adult NPC patients exhibit neurofibrillary tangles, a characteristic hallmark of Alzheimer's disease (AD). However, the cognitive, psychiatric, and neuropathological features of adult NPC and their relation to AD have yet to be explored. We systematically reviewed the literature on adult NPC with a particular focus on cognitive and neuroanatomical abnormalities. The careful study of cognition in adult NPC allows drawing critical insights in our understanding of the pathophysiology of AD as well as normal cognition.

Pulmonary Involvement in Niemann-Pick Disease: A State-of-the-Art Review.

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.

Systemic lupus erythematosus occurring in a patient with Niemann-Pick type B disease.

Niemann-Pick disease is an inherited lipid storage disorder caused by the deficiency of acid sphingomyelinase, which results in accumulation of sphingomyelin within cells of several organs and consequent tissue damage. The broad clinical spectrum of this disorder may overlap with that of systemic lupus erythematosus, hindering differential diagnosis. Herein, we report the case of a patient affected by Niemann-Pick type B disease intertwined with clinical and serological features of systemic lupus erythematosus. Two novel mutations in the SMPD1 gene were found in compound heterozygosity: p.A36V and IVS2 + 8 T > G.

[Ocular manifestation of an adult Niemann-Pick disease type B]. / Felnottkori B-típusú Niemann­Pick-betegség szemészeti manifesztációja.

Niemann-Pick disease is a rare, autosomal recessive inherited lysosomal storage disorder. The pathophysiological background for this condition is the deficiency or reduced function of the enzyme sphingomyelinase, as well as a deficiency in the intracellular cholesterol transporter protein. Due to the breakdown defect, sphingomyelin and cholesterol accumulate in the lysosomes of cells. The disease is divided into 5 subtypes (A, A/B, B, C, D). The authors present the case of a 24-year-old young man diagnosed with Niemann-Pick disease type B as a child, focusing on the ophthalmic manifestation of the disease. During the examination of the patient, fundus photographs and fundus autofluorescence imaging were taken, and optical coherence tomography (OCT), optical coherence tomography angiography (OCTA), and visual field (perimetry) examinations were performed. The characteristic macular halo and the cherry-red spot in the fovea were clearly visible during ophthalmoscopy and on the fundus photographs. The OCT images showed focal thickening with high reflectivity in the ganglion cell layer corresponding to the macular halo, and the area of the foveola was spared. With visual field examination, an intact field of vision was found on both eyes. Similar to the presented patient, symptoms in patients with the B subtype are milder, and besides the visceral symptoms, there are no neurological symptoms, and the specific ophthalmic abnormalities do not cause visual impairment. Currently, Niemann-Pick disease is considered a rare disease, and the diagnosis of the patients is often delayed or even missed due to non-specific or mild symptoms. Through consultation between medical specialties, ophthalmological examination can also contribute to the correct diagnosis in cases with mild general symptoms. Timely diagnosis can potentially lead to mitigation of symptoms thanks to the ever-expanding therapeutic options, stabilization of the disease progression, and increase of the patients' life expectancy. Orv Hetil. 2023; 164(46): 1838-1844.

Three-years misdiagnosis of Niemann Pick disease type B with novel mutations in SMPD1 gene as Budd-Chiari syndrome.

BACKGROUND: The chronic visceral subtype of acid sphingomyelinase deficiency, commonly known as Niemann Pick disease type B (NPDB), is a relatively rare autosomal recessive genetic disorder that is caused by mutations in the SMPD1 gene. NPDB with sea-blue histiocytes (SBH) clinically mimics Budd-Chiari syndrome (BCS), as it lacks specific clinical characteristics. This makes its diagnosis difficult. CASE PRESENTATION: Here, we report a case of NPDB with SBH that was misdiagnosed as BCS for three years. A 20-year-old female with abdominal distension, hepatosplenomegaly, and haematological anomalies was initially diagnosed with BCS based on her imaging finding of a thin hepatic vein and rapid blood flow at the confluence of the hepatic vein and inferior vena cava. Her bone marrow cytology found sea-blue histiocytes. Liver biopsy showed foamy cytoplasm in hepatocytes surrounded by numerous Kupffer cells. Sequencing analysis of the SMPD1 gene led to the finding of two missense mutations in the heterozygous state: C.829 T > C (p.Trp277Arg) in exon 2 (novel) and c.1805G > A (p.Arg602His) in exon 6 (already described). These findings established the diagnosis of NPDB. CONCLUSION: The patient presented with hepatosplenomegaly, haematological anomalies, and dyslipidaemia. Thus, NPDB should be considered following the exclusion of related diseases. The diagnosis of NPDB was suspected by clinical symptoms and routine laboratory tests and was confirmed by liver biopsy and gene sequencing. The novel mutation c.829 T > C in exon 2 of the SMPD1 gene has never been reported and needs to be further investigated.

Hepatopulmonary Syndrome and Multiple Arteriovenous Fistulas in a Child with Niemann-Pick Disease.

Background: Niemann-Pick disease (NPD) is caused by abnormal storage of sphingomyelin. NPD may affect the pulmonary system and cause hypoxia. In the present case, both hepatopulmonary syndrome (HPS) and pulmonary arteriovenous fistulas (PAVFs) developed in a child with NPD and were successfully treated with repeated embolization. Case Presentation: We have reported the case of a 16-year-old-girl with NPD who suffered severe hypoxia, dyspnea, fatigue, had multiple PAVFs, and was diagnosed with type 2 HPS. To improve oxygenation, 10 PAVFs were embolized. She needed re-embolization after 9 months because of hypoxia redevelopment. Conclusions: Pulmonary involvement, HPS, and/or PAVFs could be responsible for hypoxemia in patients with NPD, who should, therefore, be investigated for HPS and PAVFs. Embolization could be beneficial. Some patients may need repeated embolization.

Deficiency of niemann-pick type C-1 protein impairs release of human immunodeficiency virus type 1 and results in Gag accumulation in late endosomal/lysosomal compartments.

Human immunodeficiency virus type 1 (HIV-1) relies on cholesterol-laden lipid raft membrane microdomains for entry into and egress out of susceptible cells. In the present study, we examine the need for intracellular cholesterol trafficking pathways with respect to HIV-1 biogenesis using Niemann-Pick type C-1 (NPC1)-deficient (NPCD) cells, wherein these pathways are severely compromised, causing massive accumulation of cholesterol in late endosomal/lysosomal (LE/L) compartments. We have found that induction of an NPC disease-like phenotype through treatment of various cell types with the commonly used hydrophobic amine drug U18666A resulted in profound suppression of HIV-1 release. Further, NPCD Epstein-Barr virus-transformed B lymphocytes and fibroblasts from patients with NPC disease infected with a CD4-independent strain of HIV-1 or transfected with an HIV-1 proviral clone, respectively, replicated HIV-1 poorly compared to normal cells. Infection of the NPCD fibroblasts with a vesicular stomatitis virus G-pseudotyped strain of HIV-1 produced similar results, suggesting a postentry block to HIV-1 replication in these cells. Examination of these cells using confocal microscopy showed an accumulation and stabilization of Gag in LE/L compartments. Additionally, normal HIV-1 production could be restored in NPCD cells upon expression of a functional NPC1 protein, and overexpression of NPC1 increased HIV-1 release. Taken together, our findings demonstrate that intact intracellular cholesterol trafficking pathways mediated by NPC1 are needed for efficient HIV-1 production.

Human umbilical cord blood-derived mesenchymal stem cells improve neurological abnormalities of Niemann-Pick type C mouse by modulation of neuroinflammatory condition.

Niemann-Pick type C (NP-C) disease is a devastating developmental disorder with progressive and fatal neurodegeneration. We have used a mouse model of Niemann-Pick type C (NP-C) disease to evaluate the effects of direct intracerebral transplantation of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) on the progression of neurological disease in this order. Here, we show that hUCB-MSCs transplantation into NP-C mice prevents the loss of Purkinje neurons and inhibits cerebellar apoptotic cell death. Interestingly, these effects were associated with the modulation of inflammatory responses, as evidenced by increased anti-inflammatory cytokine IL-10, and reduced abnormal astrocytic activation. Furthermore, our results show that the hUCB-MSCs transplantation reduced the cholesterol accumulation level in neurons in NP-C mice compared with sham-transplanted animals. This study provides the first evidence that hUCB-MSCs can improve neurological symptoms in NP-C disease, suggesting it as a potential therapeutic agent against neurodegenerative diseases.

Expression of Npc1 in glial cells corrects sterility in Npc1(-/-) mice.

Niemann-Pick type C1 (NPC) disease is an autosomal recessive neurodegenerative disorder. One feature of the mouse model of NPC1 is it's infertility. We have made transgenic mice which express the Npc1 protein exclusively in fibrillary astrocytes, using the glial fibrillary acidic protein (GFAP) promoter. This selective expression of Npc1 corrects sterility in GFAP-Npc1(-/-), Npc1(-/-) mice. Counts of acidophils in the pituitary of GFAP-Npc1E, Npc1(-/-) mice, as compared Npc1(-/-) mice, and measurements of dopamine D2 receptor (DRD2) mRNA in the pituitary, suggest mechanisms for fertility enhancement. We conclude that the correction of sterility in GFAP-Npc1E, Npc1(-/-) mice is a result of restoring hypothalamic control of the pituitary.

Niemann-Pick disease in association with syringocystadenoma papilliferum.

This report describes a solitary syringocystadenoma papilliferum, a rare skin tumor, in a 9-year-old boy who was known to have Niemann-Pick disease. To our knowledge, this association has not been described in the medical literature and this is the first report describing such association.

Respiratory impairment in Niemann-Pick B disease: Two case reports and review for the pulmonologist.

Acid sphingomyelinase deficiency (ASMD), also called Niemann-Pick disease, is a storage disorder with pulmonary involvement but few respiratory symptoms in adults. However, the disease may evolve towards clinically relevant respiratory symptoms with referral to the pulmonologist for management and care. Based on two case reports illustrating respiratory impairment, the aim of this work was to review clinical features, diagnosis, respiratory prognostic and therapeutics for the pulmonologist. Overall, storage disorder should be suspected in the presence of hepatosplenomegaly and interstitial lung disease. Concomitant thrombopenia or hyperlipidemia should also draw attention. Following recent consensus guidelines, diagnosis is based on enzyme assay for ASM activity in blood, with subsequent gene sequencing once the biochemical diagnosis has been confirmed. Disease is slowly progressive and the main causes of death are respiratory and liver failure. Presence of emphysema lesions or worsening of respiratory symptoms should call for the intensification of treatment. Though enzyme replacement therapy is a promising way of development, lung transplantation might be considered for these patients in the absence of contraindication.

Highly variable neural involvement in sphingomyelinase-deficient Niemann-Pick disease caused by an ancestral Gypsy mutation.

Niemann-Pick disease (NPD), an autosomal recessive disorder resulting from mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene, is subdivided into the acute, lethal neuronopathic type A, and the chronic visceral type B, explained by the different residual activity levels of acid sphingomyelinase (ASMase). An increasing number of reports on intermediate forms, challenging this traditional clinical classification, have described a broad range of neurological manifestations; however genotype-phenotype correlations have been compromised by relatively small sample sizes and/or allelic heterogeneity. Here we present a genetically homogeneous group of 20 Gypsy patients with intermediate NPD, where we observed a surprising diversity of neurological features. All affected subjects were homozygous for the same ancestral mutation, W391G in SMPD1, yet displayed the entire spectrum of phenotypic variation observed previously in unrelated affected subjects of diverse ethnicity and disease-causing mutations, ranging from subclinical retinal involvement to severe ataxia, cognitive deficits and psychiatric disorders. The clinical heterogeneity of W391G homozygotes points to additional factors, beyond SMPD1 and residual ASMase, which determine the localization, extent and severity of neural involvement. The phenotype similarity of affected relatives suggests a possible role of genetic modifying factors. In practical terms, W391 is common in the Gypsy population and the diagnosis of NPD should be borne in mind despite the atypical course of the disease. Generally, our findings indicate that mutation analysis is of limited value in predicting brain damage, and the option of enzyme replacement therapy should be considered in intermediate NPD.

Lung disease in Niemann-Pick disease.

BACKGROUND: Lung involvement in children with Niemann-Pick disease has rarely been studied systematically. OBJECTIVE: To assess the involvement of the lung and the value of bronchoalveolar lavage in children with Niemann-Pick diseases. DESIGN: Retrospective analysis of patient records. PATIENTS: Thirteen patients, with type A (n = 1), type B (n = 10), and type C (n = 2) Niemann-Pick disease, aged 2 months to 9 years at diagnosis, were included in the study. INTERVENTIONS: Lung involvement was assessed by clinical evaluation, chest radiograph, lung computed tomography (CT) scan, pulmonary function tests, and bronchoalveolar lavage fluid analysis. RESULTS: Respiratory symptoms were present at diagnosis in 10 patients and developed during follow up in the three other patients. All patients showed signs of interstitial lung disease on chest X-ray and lung CT scan. Bronchoalveolar lavage fluid analysis (n = 7) revealed a marked accumulation of foamy macrophages (Niemann-Pick cells) in all patients. At follow up, one patient died of respiratory failure, five patients required long term oxygen therapy and seven other patients presented a chronic obstructive pulmonary disease (n = 6) or chronic cough (n = 1). CONCLUSION: Lung disease was observed in all the patients included in the present study. Bronchoalveolar lavage may be useful in Niemann-Pick diseases by showing the presence of characteristic Niemann-Pick cells.

Niemann-Pick disease type B: HRCT assessment of pulmonary involvement.

OBJECTIVE: To analyze HRCT findings in patients with Niemann-Pick disease (NPD) type B, in order to determine the frequency of HRCT patterns and their distribution in the lung parenchyma, as well as the most common clinical characteristics. METHODS: We studied 13 patients (3 males and 10 females) aged 5 to 56 years. HRCT images were independently evaluated by two observers, and disagreements were resolved by consensus. The inclusion criteria were presence of abnormal HRCT findings and diagnosis of NPD type B confirmed by histopathological examination of a bone marrow, lung, or liver biopsy specimen. RESULTS: The most common clinical findings were hepatosplenomegaly and mild to moderate dyspnea. The most common HRCT patterns were smooth interlobular septal thickening and ground-glass opacities, which were both present in all patients. Intralobular lines were present in 12 patients (92.3%). A crazy-paving pattern was observed in 5 patients (38.4%), and areas of air trapping were identified in only 1 case (7.6%). Pulmonary involvement was bilateral in all cases, with the most affected area being the lower lung zone. CONCLUSIONS: Smooth interlobular septal thickening, with or without associated ground-glass opacities, in patients with hepatosplenomegaly is the most common finding in NPD type B.

Rapid whole-genome sequencing identifies a novel homozygous NPC1 variant associated with Niemann-Pick type C1 disease in a 7-week-old male with cholestasis.

Niemann-Pick type C disease (NPC; OMIM #257220) is an inborn error of intracellular cholesterol trafficking. It is an autosomal recessive disorder caused predominantly by mutations in NPC1 Although characterized as a progressive neurological disorder, it can also cause cholestasis and liver dysfunction because of intrahepatocyte lipid accumulation. We report a 7-wk-old infant who was admitted with neonatal cholestasis, and who was diagnosed with a novel homozygous stop-gain variant in NPC1 by rapid whole-genome sequencing (WGS). WGS results were obtained 16 d before return of the standard clinical genetic test results and prompted initiation of targeted therapy.