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Background: Sitosterolemia is a rare lipid disorder caused by mutations in adenosine triphosphate-binding cassette genes (ABCG) 5 and 8., Objective: To evaluate the phenotypic/genotypic features of sitosterolemia in a group of Turkish patients., Methods: Seven probands with unexplained hematologic abnormalities and their 13 relatives were enrolled. Sterol levels were measured by gas chromatography and genetic studies were performed using Sanger sequencing. Individuals were diagnosed with sitosterolemia if they were found to have frankly elevated sitosterol level >15 μg/mL and/or pathogenic variants of the ABCG5/ABCG8., Results: The seven probands and their six relatives  were diagnosed with frank sitosterolemia, and all these patients had hematologic abnormalities. The remaining seven relatives were asymptomatic heterozygous carriers. Three novel variants in the ABCG5 gene (c.161G>A, c.1375C>T, IVS10-1G>T), one novel variant in the ABCG8 gene (c.1762G>C) and one known variant in the ABCG5 gene (c.1336 C>T) were identified. No variant was identified in one case. The mean sitosterol level was significantly higher and mean platelet count was significantly lower in patients with homozygous variants compared to heterozygous variants (p<0.05, for all). Diets low in plant sterols were recommended for 13 symptomatic cases. Four homozygotes received ezetimibe, and their splenomegaly, anemia, and thrombocytopenia completely resolved except one., Conclusion: The five pathogenic variants identified in this study indicate the genetic heterogeneity of sitosterolemia in Turkish population. Patients with unexplained hematologic abnormalities (specifically macrothrombocytopenia) should have their sterol level measured as initial testing. Ezetimibe can be a good choice for sitosterolemia., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2021. Published by Elsevier Inc.)

Purpose: Evaluation standards and treatment initiation timing have been debated for a long time, particularly for late-onset Fabry disease (FD), because of its slow progression. However, early initiation of enzyme replacement therapy (ERT) for FD could be effective in stabilizing the disease progression and potentially preventing irreversible organ damage. We aimed to examine globotriaosylceramide (Gb3) deposits in patients' endomyocardial biopsies to understand the early pathogenesis of FD cardiomyopathy., Methods: Immunofluorescent (IF) staining of Gb3 and lysosomal-associated membrane protein 1 (LAMP-1) was performed on endomyocardial biopsies of patients suspected of Fabry cardiomyopathy who had negative or only slight Gb3 accumulation determined by toluidine blue staining and electron microscopic examination., Results: The IF staining results revealed that all patients examined had abundant Gb3 accumulation in their cardiomyocytes, including the ones who are negative for inclusion bodies. Furthermore, we found that early Gb3 deposits were mostly confined within lysosomes, while they appeared extralysosomally at a later stage., Conclusion: A significant amount of lysosomal Gb3 deposits could be detected by IF staining in cardiac tissue before the formation of inclusion bodies, suggesting the cardiomyocytes might have been experiencing cellular stress and damage early on, before the appearance of typical pathological changes of FD during the disease progression.

Objectives: The level of 8-hydroxy-2-deoxyguanosise (8-OHdG) is a marker of oxidative stress. The objective of this study was to evaluate the effect of enzyme replacement therapy (ERT) on the level of 8-OHdG in patients with Fabry cardiomyopathy and the clinical evolution of Fabry cardiomyopathy., Methods: We measured the serum levels of 8-OHdG in 20 healthy control and 22 patients with Fabry cardiomyopathy before and after ERT., Results: The mean lysoGb3 and 8-OHdG levels was significantly increased in patients with Fabry cardiomyopathy compared with that of control subjects (lysoGb3, 3.6 ± 1.1 nM vs. 0.4 ± 0.1 nM, p < 0.01; 8-OHdG, 4.5 ± 0.5 ng/mL vs. 3.4 ± 0.4 ng/mL, P < 0.05). The mean lysoGb3 and 8-OHdG levels was significantly reduced after ERT for 14.2 months (lysoGb3, 3.6 ± 1.1 nM vs. 2.9 ± 1.1 nM, P < 0.05; 8-OHdG, 4.5 ± 0.5 ng/mL to 4 ± 0.4 ng/mL, P < 0.05). These changes were accompanied by decreases in LVM and LVMI., Conclusions: We demonstrated that the serum 8-OHdG levels is increased in patients with Fabry cardiomyopathy (FC) and that successful management of FC with ERT is associated with a decrease in this oxidative stress marker. Serum 8-OHdG levels can be used not only as a noninvasive biomarker of oxidative stress in patients with FC but also an objective and quantitative parameter in the follow-up of patients during ERT., (Copyright © 2017. Published by Elsevier Inc.)

Background: Fabry disease (FD) is a lysosomal storage disease in which glycosphingolipids (GB3) accumulate in organs of the human body, leading to idiopathic hypertrophic cardiomyopathy and target organ damage. Its pathophysiology is still poorly understood., Objectives: We aimed to generate patient-specific induced pluripotent stem cells (iPSC) from FD patients presenting cardiomyopathy to determine whether the model could recapitulate key features of the disease phenotype and to investigate the energy metabolism in Fabry disease., Methods: Peripheral blood mononuclear cells from a 30-year-old Chinese man with a diagnosis of Fabry disease, GLA gene (IVS4+919G>A) mutation were reprogrammed into iPSCs and differentiated into iPSC-CMs and energy metabolism was analyzed in iPSC-CMs., Results: The FD-iPSC-CMs recapitulated numerous aspects of the FD phenotype including reduced GLA activity, cellular hypertrophy, GB3 accumulation and impaired contractility. Decreased energy metabolism with energy utilization shift to glycolysis was observed, but the decreased energy metabolism was not modified by enzyme rescue replacement (ERT) in FD-iPSCs-CMs., Conclusion: This model provided a promising in vitro model for the investigation of the underlying disease mechanism and development of novel therapeutic strategies for FD. This potential remedy for enhancing the energetic network and utility efficiency warrants further study to identify novel therapies for the disease., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Fabry disease is a lysosomal storage disorder with an incidence of 1:1600 for the late-onset IVS4+919G>A cardiac variant mutation in Taiwan. Signs and symptoms of this cardiac variant include left ventricular hypertrophy, mitral insufficiency and/or arrhythmias. The search for biomarkers that might predict the clinical outcomes and guide treatment options is important. We thus investigated relationships between Fabry disease biomarkers (such as globotriaosylceramide (Gb 3 ), globotriaosylsphingosine (lyso-Gb 3 )/related analogues) and age, gender, enzyme activity, clinical manifestations and severity of the disease in these patients., Method: Urine and plasma biomarkers were analyzed using tandem mass spectrometry. A large cohort of 191 adult and pediatric Fabry patients carrying the IVS4+919G>A mutation was studied. Some patients were members of the same family., Results: Our results show that the plasma lyso-Gb 3 level, and urinary analogue levels of lyso-Gb 3 at m/z (+16), (+34), and (+50) adjusted for gender and age had a positive association with the left ventricular mass index, and/or the Mainz Severity Score Index., Conclusions: It might thus be of particular interest to monitor children with high levels of these biomarkers, as part of a longitudinal study in order to determine if the excretion profile at a young age is predictive of the outcomes of disease severity in adulthood., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Fabry disease (FD) causes progressive glycosphingolipid accumulation and damage in various organs, and several proinflammatory processes may be involved in this disease. Enzyme replacement therapy (ERT) can reduce the severity of Fabry cardiomyopathy (FC), but whether ERT could attenuate proinflammatory cytokines in FC remains unclear. In this study, we attempted to evaluate the efficacy of ERT on proinflammatory cytokines and vascular cell adhesion biomarkers., Methods: We enrolled 25 patients with FC and administered ERT to them according to the present clinical guideline. We analyzed and compared echocardiographic and blood examination results between 25 patients with FD without left ventricular hypertrophy (LVH), 25 patients with FC with LVH who were receiving ERT, and 25 healthy age- and sex-matched controls. The parameters of cardiac function at baseline and 12 months after ERT were assessed through echocardiography, and the expression profiles of proinflammatory biomarkers were determined., Results: Left ventricular mass (LVM), LVM index (LVMI), interventricular septal thickness at diastole, and serum levels of globotriaosylsphingosine (Gb3) were elevated in patients with FC. Meanwhile, several proinflammatory cytokines, including interleukin (IL)-6, IL-2, IL-1b, tumor necrosis factor-α, intercellular adhesion molecule, soluble vascular cell adhesion molecule, and monocyte chemoattractant protein-1 (MCP-1) were concomitantly increased. ERT significantly reduced these transthoracic echocardiographic parameters and lyso-Gb3 and proinflammatory cytokine levels. The changes in IL-6, MCP-1, and lyso-Gb3 levels were positively correlated with the change in LVMI., Conclusions: Our study has revealed that proinflammatory biomarkers, particularly IL-6 and MCP-1, may represent effective biomarkers for evaluating ERT outcomes in patients with FC., (Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Propionyl-CoA carboxylase (PCC) is a mitochondrial enzyme involved in the catabolism of several essential amino acids and odd chain fatty acids. Previous PCC assays have involved either a radiometric assay or have required mitochondria isolation and/or enzyme purification., Methods: We developed an enzymatic method to analyze PCC activity in phytohemagglutinin (PHA) stimulated lymphocytes that involves high performance liquid chromatography., Results: The method shows good linearity and sensitivity. PCC activity was unaffected even when lymphocytes were isolated and PHA stimulated after a whole blood sample had been stored at 4°C for 5days. This indicates that this method is suitable for analyzing samples from distant medical centers. The PCC activity of patients with propionic acidemia was found to be much lower than that of normal individuals and carriers. However, this PCC assay is significantly affected by the red blood cell contamination. In conclusion, this is a reliable method for performing PCC assays and only requires 0.5 to 1.0ml of whole blood from newborns., Conclusions: The PCC assay established in this study is useful for the confirmation of PA in individuals, and prenatal diagnosis and genetic counseling for the affected families., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background & Aims: Many studies have reported that serum total homocysteine (tHcy) levels in cystathionine-beta-synthase (CBS) carriers are usually normal and only elevated after a methionine load. However, the amount of methionine required for a loading test is non-physiological and is never reached with regular feeding. Therefore, CBS carriers do not seem to be at an increased risk of cardiovascular diseases. However, the risk of cardiovascular diseases of CBS carriers with folate deficiency has not been studied. We recently found an extraordinarily high carrier rate (1/7.78) of a novel CBS mutation (p.D47E, c.T141A) in an Austronesian Taiwanese Tao tribe who live in a geographic area with folate deficiency. We evaluated if the CBS carriers tend to have higher fasting serum tHcy concentrations than non-carriers in presence of folate deficiency., Methods: The serum tHcy and folate levels before and after folate replacement were measured in 48 adult Tao carriers, 40 age-matched Tao non-carriers and 40 age-matched Han Taiwanese controls., Results: The serum tHcy level of the Tao CBS carriers (17.9 ± 3.8 μmol/l) was significantly higher than in Tao non-carriers (15.7 ± 3.5 μmol/l; p < 0.008) and Taiwanese controls (11.8 ± 2.9 μmol/l; p < 0.001). Furthermore, a high prevalence of folate deficiency in the Tao compared with the Taiwanese controls (4.9 ± 1.8 ng/ml vs. 10.6 ± 5.5 ng/ml; p < 0.001) was also noted. Of note, the difference in tHcy levels between the carriers and non-carriers was eliminated by folate supplementation. (carriers:13.65 ± 2.13 μmol/l; non-carriers:12.39 ± 3.25 μmol/l, p = 0.321)., Conclusions: CBS carriers tend to have a higher tHcy level in the presence of folate deficiency than non-carriers. Although many reports have indicated that CBS carriers are not associated with cardiovascular disease, the risk for CBS carriers with folate deficiency has not been well studied. Owing to a significantly elevated level of fasting tHcy without methionine loading, it is important to evaluate the risk of cardiovascular disease in CBS carriers with folate deficiency., (Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background: Clinical observation and treatment of children with homozygous familial hypercholesterolemia (HoFH) has rarely been reported. We report clinical observations and treatment of 10 ethnic Chinese children with HoFH due to low-density lipoprotein receptor (LDLR) defect., Objectives: In children with HoFH, we evaluated the response to conventional cholesterol-lowering drug therapy and performed LDLR gene analysis., Methods: A retrospective review of lipid profile changes in pediatric patients diagnosed with HoFH seen in our pediatric endocrinology outpatient clinic was performed. HoFH was diagnosed by molecular study of these patients and their parents., Results: One novel (c.64del G) and 12 known mutations were found in the LDLR gene. Mutation of p.C308Y was the most common and was found in 26% of the studied alleles.Seven patients had fair responses to conventional drug therapy (high-dose statin with ezetimibe) with a reduction of 50% or more of the total cholesterol levels. The low-density lipoprotein-cholesterol levels of three patients decreased to lower than 160 mg/dL. One who had a good response to conventional drug therapy developed significant atheromatous plaques (largest plaque: 7.4 × 2.7 cm) in the extracranial carotid arteries and myocardial ischemia changes at 11 years old., Conclusion: The results suggest that despite aggressive therapy, many patients are not well controlled; atherosclerosis may progress, and novel therapies are required., (Copyright © 2015 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

Background: Interest in lysosomal storage diseases in newborn screening programs has increased in recent years. Two techniques, fluorescence (4-MU) and tandem mass spectrometry (MS/MS) methods are frequently used. We report a pilot study of large scale newborn screening for Fabry, Pompe, Gaucher, and MPS I diseases by using the MS/MS method in Taiwan and compared the performance of the MS/MS with 4-MU methods., Methods: More than 100,000 dried blood spots (DBSs) were collected consecutively as part of the national Taiwan newborn screening programs. The enzyme activities were detected by the MS/MS method from a DBS punch. Mutation analysis was further performed for newborns with detected enzyme deficiency., Results: The DNA sequence analysis for suspected cases revealed 64 newborns with confirmed Fabry mutations, 16 were classified as infantile or late-onset Pompe disease, and 1 was characterized as Gaucher disease. The positive predict value increased from 4.0% to 7.1% in the Pompe study, and from 61.0% to 95.5% in the Fabry study by the MS/MS method compared to 4-MU assay., Conclusions: The MS/MS method has been validated as a more specific, powerful and efficient tool than the 4-MU assay. It also provided a multiplex solution of newborn screening for lysosomal storage diseases., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Previous studies revealed a high incidence of late-onset Fabry disease mutation, IVS4+919G>A, in Taiwan. However, the natural course is largely unclear and suitable biomarkers for monitoring disease progress are unavailable., Methods and Results: Patients carrying IVS4+919G>A or classical Fabry mutations were enrolled in this study. The subjects ranged from newborn to eighty year old adults. Plasma globotriaosylceramide (Gb3) and globotriaosylsphingosine (lysoGb3) were measured by LC-MS/MS in subjects to evaluate the sensitivity of these two biomarkers. All adult males and symptomatic females could be distinguished from healthy controls by an elevated plasma lysoGb3 level. The lysoGb3 level was also related to the left ventricular mass considering gender and age (p<0.01). Moreover, approximately 70% of male and 45% of female newborns already had an elevated plasma lysoGb3 level which increased gradually as the subjects got older (p<0.01)., Conclusions: Plasma lysoGb3 is a more sensitive and reliable biomarker than plasma Gb3. LysoGb3 also correlated with age and left ventricular mass index in Fabry patients with IVS4+919G>A mutation. Because lots of infants with the IVS4+919G>A mutation already had elevated lysoGb3 levels at birth, that indicates that the development of hypertrophic cardiomyopathy may require a long and insidious course after lysoGb3 accumulation., (© 2013. Published by Elsevier B.V. All rights reserved.)

Background: As an X-linked genetic disorder, Fabry disease was first thought to affect males only, and females were generally considered to be asymptomatic carriers. However, recent research suggests that female carriers of Fabry disease may still develop vital organ damage causing severe morbidity and mortality. In the previous newborn screening, from 299,007 newborns, we identified a total of 20 different Fabry mutations and 121 newborns with Fabry mutations. However, we found that most female carriers are not detected by enzyme assays., Methods: A streamlined method for high resolution melting (HRM) analysis was designed to screen for GLA gene mutations using a same PCR and melting program. Primer sets were designed to cover the 7 exons and the Chinese common intronic mutation, IVS4+919G>A of GLA gene., Results: The HRM analysis was successful in identifying heterozygous and hemizygous patients with the 20 surveyed mutations. We were also successful in using this method to test dry blood spots of newborns afflicted with Fabry mutations without having to determine DNA concentration before PCR amplification., Conclusion: The results of this study show that HRM could be a reliable and sensitive method for use in the rapid screening of females for GLA mutations., (Copyright © 2011 Elsevier B.V. All rights reserved.)

6-Pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is the most frequent form of tetrahydrobiopterin (BH4) deficiency related to hyperphenylalaninemia (HPA). PTPS deficiency may not only cause a typical phenylketonuric phenotype, but is also accompanied by various neurological signs and symptoms due to impaired synthesis of catecholamines and serotonin. The treatment of PTPS deficiency is aimed at normalizing phenylalanine levels and brain neurotransmitters. The BH4 can be administered to normalize phenylalanine (PHE) levels easily, but, owing to severe side effects, the neurotransmitters, L-DOPA and 5-hydroxytryptophan, should be administered for these patients very carefully. However, optimal dosage of the neurotransmitters for PTPS deficiency patients is difficult to be determined. Several reports have described unsatisfied outcomes in a large percentage of patients with PTPS deficiency, despite early detection and treatment. Between 1988 and 2000, 12 newborns with PTPS deficiency identified by newborn screening were referred and received early treatment at our hospital. The mean IQ score of these 12 patients was 96.7 (±9.7; range: 86-119), which is considerably higher than previous reports of other populations of PTPS-deficient patients. In this report, we reviewed the disorders of BH4 briefly and then described treatments of our PTPS-deficient patients., (Copyright © 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.)

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy., (Copyright © 2011. Published by Elsevier B.V. All rights reserved.)

Giant congenital melanocytic nevi are rare, with an estimated incidence of approximately 1 in 20,000 live births. They increase the lifetime risk for malignant melanoma and neurological deficits, including leptomeningeal melanocytosis and epilepsy. Recently, we encountered two patients in whom giant congenital melanocytic nevi were noted at birth. Case 1 presented with the largest nevus spreading across the posterior scalp, neck, chest wall, shoulder and upper back. At the age of 2 months, magnetic resonance imaging (MRI) was performed and no leptomeningeal melanocytosis was found. Case 2 presented with a huge nevus covering most parts of the lower abdomen, lower back, buttocks and bilateral upper thighs. She also had normal MRI findings in the newborn period. At the age of 7 years, leptomeningeal thickening on the surface of the junction between the pons and midbrain was found on brain MRI although she was neurologically asymptomatic. Here, we describe these two cases with congenital melanocytic nevi and review the literature about its clinical manifestations, outcomes, risks for malignant melanoma and neurocutaneous melanosis, and possible surgical interventions.

Marfan syndrome has been associated with approximately 562 mutations in the fibrillin-1 (FBN1) gene. Mutation scanning of the FBN1 gene with DNA direct sequencing is time-consuming and expensive because of its large size. This study analyzed the diagnostic value of high-resolution melting analysis as an alternative method for scanning of the FBN1 gene. A total of 75 polymerase chain reaction (PCR) amplicons (179-301bp, average 256bp) that covered the complete coding regions and splicing sites were evaluated on the 96-well LightCycler system. Melting curves were analyzed as fluorescence derivative plots (-dF/dT vs. temperature). To determine the sensitivity of this method, a total of 82 samples from patients with Marfan syndrome and 50 unaffected individuals were analyzed. All mutations reported in this study had been confirmed previously by direct sequencing analysis. Melting analysis identified 48 heterozygous variants. The variant c.3093 G>T (exon 25) was incorrectly identified by melting curve analysis. The sensitivity of the technique in this sample was 98.78% (81/82). This study demonstrated that high-resolution melting analysis is a reliable gene scanning method with greater speed than DNA sequencing. Our results support the use of this technology as an alternative method for the diagnosis of Marfan syndrome as well as its suitability for high-throughput mutation scanning of other large genes.

In this study, we attempted to determine if different locations of a tumor influence the hypothalamopituitary axis function and outcomes with childhood craniopharyngiomas. The preoperative, postoperative, and long-term follow-up endocrinological disturbances of 66 children with a craniopharyngioma were retrospectively studied. The patients were divided into two subgroups according to the location of the tumor (intrasellar and third ventricle floor). The mean age at onset was 8.02 (range, 1.42-17.58)years. These patients were followed-up for a median duration of 7.2 (range, 2-22)years. Vision problems as the first symptom were more common in Group One (with intrasellar tumors) compared to Group Two (55.6% vs 15.4%; p=0.001; Fisher's exact test). Increased intracranial pressure was the most common initial symptom in patients in Group Two (51.3%) and the second most common symptom in Group One (37%). The majority of patients in both Group One and Group Two required some forms of pituitary hormone supplements (96% vs 84%). At the last follow-up, more patients with intrasellar craniopharyngiomas needed cortisone supplements (79.2% in Group One vs 45.9% in Group Two; p=0.016; Fisher's exact test); however, children with third ventricle floor tumors had more prevalent weight gain (4.2% in Group One vs 27.0% in Group Two; p=0.038; Fisher's exact test). There were different initial presentations and endocrinological outcomes between children with intrasellar and third ventricle floor craniopharyngiomas. The intrasellar tumors had greater pituitary hormone disturbance. However, at the long-term follow-up, children with third ventricle floor tumors had a greater prevalence of being overweight and obese, which was associated with hypothalamic dysfunction.

6-Pyruvoyl-tetrahydropterin synthase (6PTPS) deficiency is a major cause of biopterin deficiency. 6PTPS patients usually have an elevated serum phenylalanine level, a deficiency of neurotransmitters (serotonin and dopamine), and neurological symptoms, if without treatment. We herein investigated the possibility of neurological dysfunction in early-treated patients. In the study, 12 early-treated 6PTPS patients were studied. Their auditory simple reaction time, movement rhythm variation (MRV), somatosensory evoked potentials to median nerve stimulation, and hand muscle responses to transcranial magnetic stimulation, were measured. MRV is a test of repetitive voluntary movements, and was used with and without auditory cues at 0.3 Hz. The 6PTPS patients had an increased motor threshold but normal motor and sensory central conduction times. They performed very well in simple reactions (6PTPS 208.4+/-16.7 ms, control 200.3+/-11.7 ms, p=0.18), but not in continuous tasks. The continuous performance tests showed that MRV had increased in the 6PTPS patients (with cues: 6PTPS 7.35+/-0.94, control 5.47+/-0.80, p<0.0001; without cues: 6PTPS 9.87+/-1.44, control 6.59+/-0.68, p<0.0001). Without cues, MRV had increased in both the 6PTPS and control groups, but more significantly in the 6PTPS patients (6PTPS 2.51+/-0.97, control 1.25+/-0.42; p=0.0001). Our findings indicate that early-treated 6PTPS patients have subtle neurological dysfunctions. They may not maintain movement rhythm as well as normal subjects, even with external cues. Hence, MRV is a good method to assess motor control.