Simplified Criteria for Identification of Familial Hypercholesterolemia in Children: Application in Real Life.

BACKGROUND: The diagnosis of familial hypercholesterolemia (FH) in children is primarily based on main criteria including low-density lipoprotein cholesterol (LDL-C) levels, increased in the proband and relatives, and its inheritance. Two other relevant parameters are symptoms, rarely occurring in children, as rare are the FH homozygous patients, and the mutation detection of related genes. The latter allows the final diagnosis, although it is not commonly available. Moreover, the application of diagnostic scores, useful in adults, is poorly applied in children. The aim of this study was to compare the reliability of criteria here applied with different scores, apart from genetic analysis, for FH diagnosis. The latter was then confirmed by genetic analysis. METHODS: n. 180 hypercholesterolemic children (age 10.2 ± 4.6 years) showing LDL-C levels ≥95th percentile (age- and sex-related), the dominant inheritance pattern of hypercholesterolemia (including LDL-C ≥95th percentile in one parent), were considered potentially affected by FH and included in the study. The molecular analysis of the LDLR, APOB and PCSK9 genes was applied to verify the diagnostic accuracy. Biochemical and family history data were also retrospectively categorized according to European Atherosclerosis Society (EAS), Simon Broome Register (SBR), Pediatric group of the Italian LIPIGEN (LIPIGEN-FH-PED) and Dutch Lipid Clinic Network (DLCN) criteria. Detailed kindred biochemical and clinical assessments were extended to three generations. The lipid profile was detected by standard laboratory kits, and gene analysis was performed by traditional sequencing or Next-Generation Sequencing (NGS). RESULTS: Among 180 hypercholesterolemic subjects, FH suspected based on the above criteria, 164/180 had the diagnosis confirmed, showing causative mutations. The mutation detection rate (MDR) was 91.1%. The scoring criteria proposed by the EAS, SBR and LIPIGEN-FH-PED (resulting in high probable, possible-defined and probable-defined, respectively) showed high sensitivity (~90%), low specificity (~6%) and high MDR (~91%). It is noteworthy that their application, as a discriminant for the execution of the molecular investigation, would lead to a loss of 9.1%, 9.8% and 9.1%, respectively, of FH-affected patients, as confirmed by the genetic analysis. DLCN criteria, for which LDL-C cut-offs are not specific for childhood, would lead to a loss of 53% of patients with mutations. CONCLUSIONS: In the pediatric population, the combination of LDL-C ≥95th percentile in the proband and the dominant inheritance pattern of hypercholesterolemia, with LDL-C ≥95th percentile in one parent, is a simple, useful and effective diagnostic criterion, showing high MDR. This pattern is crucial for early FH diagnosis. EAS, SBR and LIPIGEN-FH-PED criteria can underestimate the real number of patients with gene mutations and cannot be considered strictly discriminant for the execution of molecular analysis.

Impact of 12-SNP and 6-SNP Polygenic Scores on Predisposition to High LDL-Cholesterol Levels in Patients with Familial Hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) comprises high LDL-cholesterol (LDL-c) levels and high cardiovascular disease risk. In the absence of pathogenic variants in causative genes, a polygenic basis was hypothesized. METHODS: In a population of 418 patients (excluding homozygotes) with clinical suspicion of FH, the FH-causative genes and the regions of single nucleotide polymorphisms (SNPs) included in 12-SNP and 6-SNP scores were sequenced by next-generation sequencing, allowing for the detection of pathogenic variants (V+) in 220 patients. To make a comparison, only patients without uncertain significance variants (V-/USV-) were considered (n = 162). RESULTS: Higher values of both scores were observed in V+ than in V-. Considering a cut-off leading to 80% of V-/USV- as score-positive, a lower prevalence of patients positive for both 12-SNP and 6-SNP scores was observed in V+ (p = 0.010 and 0.033, respectively). Mainly for the 12-SNP score, among V+ patients, higher LDL-c levels were observed in score-positive (223 mg/dL -IQR 187-279) than in negative patients (212 mg/dL -IQR 162-240; p = 0.006). Multivariate analysis confirmed the association of scores and LDL-c levels independently of age, sex, and presence of pathogenic variants and revealed a greater association in children. CONCLUSIONS: The 12-SNP and 6-SNP polygenic scores could explain hypercholesterolemia in patients without pathogenic variants as well as the variability of LDL-c levels among patients with FH-causative variants.

Apolipoprotein B and Lipid Profile in Italian Children and Adolescents.

RATIONALE: The prevention of cardiovascular (CV) disease is mandatory from childhood onwards. Among biochemical markers related to the clinical cardiovascular outcome, LDL cholesterol (LDL-C), non-HDL-C and apolipoprotein B (ApoB) are recognized as main target parameters. Emphasis on ApoB concentrations is growing, as representative of any class of atherogenic lipoprotein. This consideration allows checking of subjects under 18 years of age when the CV risk occurs. The aim of this study is to evaluate ApoB levels in a sample of Italian hyperlipidemic children and adolescents, and their siblings, to test any relationship with their lipid profile. METHODS: A retrospective study, including 1877 children and adolescents (aged 0-18 years), was performed. Clinical and biochemical data were selected from a database, including the lipid profile, ApoB analysis and anthropometric parameters of any proband. Participants had been checked as potentially hyperlipidemia affected, the suspicion raised by familial CV risk or because the dyslipidemia was already known. Data from the first visit at the University Hospitals in Rome and Turin were collected. Patients affected by secondary hyperlipidemia or obesity were excluded. Blood test analysis was performed in fasting conditions by automated commercial kits. Participants were classified according to gender, age (stratified in subgroups: 0-5, 6-10, 11-14, and 15-18 years old) and anthropometric parameters, referred to as weight in Kg and height in cm, and BMI calculated. Lipid profile results were stratified in relation to acceptable, borderline, or increased levels, as indicated by NCEP, and any potential relation with ApoB established. Statistics were performed by Epi-Info 7 programs to evaluate the variance analysis. Either parent could sign the informed consent. RESULTS: Among the whole sample n.1010 and n.867 participants were females and males, respectively. TC values acceptable (≤170 mg/dL), borderline (171-200 mg/dL) and elevated (≥201 mg/dL) were found in 411 (22%), 585 (31%) and 881 (47%) participants, respectively. The LDL-C cut-off considered was 110 mg/dL (90° percentile). Mean ApoB progressively increased from 65 to 110 mg/dL according to TC levels and resulted in significant correlation when any age subgroup and gender was considered. The highest ApoB values, TC and LDL-C related, were found in the youngest subgroup, regardless of gender. CONCLUSION: ApoB results increase progressively and in parallel with TC and LDL-C and represent a further parameter to distinguish between normal and hyperlipidemic subjects. Serum levels are close to 70 mg/dL and to 100 mg/dL in the former and latter group, respectively.

Clinical Approach in the Management of Paediatric Patients with Familial Hypercholesterolemia: A National Survey Conducted by the LIPIGEN Paediatric Group.

Detection and treatment of patients with familial hypercholesterolemia (FH) starting from childhood is fundamental to reduce morbidity and mortality. The activity of National realities such as the LIPIGEN (LIpid transPort disorders Italian GEnetic Network) Paediatric Group, founded in 2018, is a milestone in this context. The aim of this exploratory survey, conducted in October 2021 among Italian lipid clinics included in the LIPIGEN Paediatric Group, was to investigate the current clinical approach in the management and treatment of paediatric patients with suspected FH. A digital questionnaire composed of 20 questions investigating nutritional treatment and nutraceutical and pharmacological therapy for children and adolescents with FH was proposed to the principal investigators of 30 LIPIGEN centres. Twenty-four centres responded to the section referring to children aged < 10 years and 30 to that referring to adolescents. Overall, 66.7% of children and 73.3% of adolescents were given lipid-lowering nutritional treatment as the first intervention level for at least 3-4 months (29.2% and 23.3%) or 6-12 months (58.3% and 53.3%). Nutraceuticals were considered in 41.7% (regarding children) and 50.0% (regarding adolescents) of the centres as a supplementary approach to diet. Lipid-lowering drug therapy initiation was mainly recommended (91.7% and 80.0%). In 83.3% of children and 96.7% of adolescents, statins were the most frequently prescribed drug. We highlighted several differences in the treatment of paediatric patients with suspected FH among Italian centres; however, the overall approach is in line with the European Atherosclerosis Society (EAS) recommendations for FH children and adolescents. We consider this survey as a starting point to reinforce collaboration between LIPIGEN centres and to elaborate in the near future a consensus document on the management of paediatric patients with suspected FH so as to improve and uniform detection, management, and treatment of these patients in our country.

The Effects of Omega 3 and Omega 6 Fatty Acids on Glucose Metabolism: An Updated Review.

Massive changes have occurred in our diet. A growing consumption of vegetal oils rich in omega-6 (ω-6) and a depletion of omega-3 (ω-3) fatty acids (FAs) in our food has led to an imbalance between ω-3 and ω-6. In particular, eicosapentaenoic (EPA)/arachidonic acid (AA) ratio seems to be an indicator of this derangement, whose reduction is associated to the development of metabolic diseases, such as diabetes mellitus. Our aim was therefore to investigate the literature on the effects of ω-3 and ω-6 FAs on glucose metabolism. We discussed emerging evidence from pre-clinical studies and from clinical trials. Notably, conflicting results emerged. Source of ω-3, sample size, ethnicity, study duration and food cooking method may be responsible for the lack of univocal results. High EPA/AA ratio seems to be a promising indicator of better glycemic control and reduced inflammation. On the other hand, linoleic acid (LA) appears to be also associated to a minor incidence of type 2 diabetes mellitus, although it is still not clear if the outcome is related to a reduced production of AA or to its intrinsic effect. More data derived from multicenter, prospective randomized clinical trials are needed.

Mediterranean Dietary Treatment in Hyperlipidemic Children: Should It Be an Option?

BACKGROUND: Diet is considered the cornerstone of lipid management in hyperlipidemic children but evidence to demonstrate the effects of nutrient benefits on the lipid profile is limited. AIM: The aim of this study is to evaluate the impact of the Mediterranean diet on low-density lipoprotein (LDL-C) and non-high density lipoprotein (HDL-C) decrease in primary hyperlipidemia affected children and in the achievement of therapeutical target levels. METHODS: A retrospective cohort study was used, recruiting n = 223 children (10.05 ± 3.26 mean age years) with familial hypercholesterolemia (FH) (n = 61, 27%) and polygenic hypercholesterolemia (PH) (n =162, 73%). Secondary hyperlipidemias were excluded. Based on LDL-C and non-HDL-C decrease, participants were divided into two groups, named the Responder Group and Non-Responder Group. Participants and their families underwent dietary education by an expert nutritionist and were asked to fill in a weekly diary to be delivered at visits. Dietary indications were in line with daily caloric requirement, daily food quality and quantity intakes typical of the Mediterranean diet. These include carbohydrates, extra virgin olive oil, yoghurt and milk derivatives, fish and vegetable proteins, fresh seasonal vegetables and fresh fruits. Nuts or almonds were also recommended. The advice to limit intakes of meat, in particular red meat, and caution against junk food and sugar added food and beverages was provided. At medical visits, carried out at baseline (T0) and 6 months later (T1), children underwent anthropometric measurements and blood collection. Standard kits and methods were applied for lipid analysis. Statistical methods were performed by SAS version 9.4 (SAS Institute, Cary, NC, USA). Signed informed consent was given by parents according to the Declaration of Helsinki and the study was approved by the Local Committee. RESULTS: The Responder Group (n = 156/223, 70%) included 45 FH and 111 PH children, while the Non-Responder Group (n = 67/223, 30%) included 16 FH and 51 PH children. The Responder Group showed total cholesterol (TC), LDL-C and non-HDL-C median percentage decreases of 9.45, 13.51 and 10.90, respectively. These statistically significant changes (p ≤ 0.0001) were similar in the FH and PH subgroups but just PH subjects reached the LDL-C and non-HDL-C target, which fell below 130 mg/dL and 145 mg/dL, respectively. Saturated fatty acids (SFAs) were the main dietary parameter that distinguished between the Responder Group and the Non-Responder Group (p = 0.014). Positive correlations were found at T1 between dietary total lipids, SFAs and cholesterol with serum LDL-C, non-HDL-C and TC variations. These latter serum parameters had an inverse correlation with dietary carbohydrate at T1. Among macronutrients, SFAs were finally demonstrated to be the predictor of serum lipids variation at T1. CONCLUSIONS: The dietary intervention with a Mediterranean diet in children with primary hyperlipidemia significantly improves the lipid profile both in FH and PH subgroups and allows target levels of LDL-C and non-HDL-C in PH subjects to be reached. Responsiveness benefits should be primarily attributed to the reduction in SFAs, but changes in dietary lipids, cholesterol and carbohydrate intake may also play a role. In contrast, the Non-Responder Group showed a worsening of lipid profile regarding the unchanged diet.

Genetic spectrum of familial hypercholesterolemia and correlations with clinical expression: Implications for diagnosis improvement.

Familial hypercholesterolemia (FH) is the most common genetic disease caused by variants in LDLR, APOB, PCSK9 genes; it is characterized by high levels of LDL-cholesterol and premature cardiovascular disease. We aim to perform a retrospective analysis of a genetically screened population (528 unrelated patients-342 adults and 186 children) to evaluate the biochemical and clinical correlations with the different genetic statuses. Genetic screening was performed by traditional sequencing and some patients were re-analyzed by next-generation-sequencing. Pathogenic variants, mainly missense in the LDLR gene, were identified in 402/528 patients (76.1%), including 4 homozygotes, 17 compound heterozygotes and 1 double heterozygotes. A gradual increase of LDL-cholesterol was observed from patients without pathogenic variants to patients with a defective variant, to patients with a null variant and to patients with two variants. Six variants accounted for 51% of patients; a large variability of LDL-cholesterol was observed among patients carrying the same variant. The frequency of pathogenic variants gradually increased from unlikely FH to definite FH, according to the Dutch Lipid Clinic Network criteria. Genetic diagnosis can help prognostic evaluation of FH patients, discriminating between the different genetic statuses or variant types. Clinical suspicion of FH should be considered even if few symptoms are present or if LDL-cholesterol is only mildly increased.

Lipid profile assessed in the family pediatrician's office: the COLIBRI'- SIMPeF study.

There is limited information on the prevalence of dyslipidemia in the Italian pediatric population. Aim of the study was to evaluate total cholesterol, high-density lipoprotein (HDL)-cholesterol and triglyceride levels, and associated factors in a large sample of Italian children, applying a micro-sampling procedure in the family pediatrician's office. In a population of 1910 children (50.2% males, age 7-11 years), 27.6% was overweight or obese and 28.3% had at least one parent with referred hypercholesterolemia. Total cholesterol and triglyceride levels were elevated in 4.5% and 23.5% of the subjects, respectively, while HDL cholesterol was below 40 mg/dl in 3.3%. Male gender (OR 1.58, 95% CI 1.01-2.49) and positive family history (OR 2.13, 95% CI 1.36-3.32) were independent predictors of hypercholesterolemia, while BMI z-score was associated with low HDL cholesterol (OR 1.46, 95% CI 1.13-1.88) and high levels of triglycerides (OR 1.39, 95% CI 1.26-1.55).Conclusion: The prevalence of dyslipidemia in our sample is worthy of attention. The study suggests the opportunity and feasibility to check for the presence of dyslipidemia at the family pediatrician's office. Familiarity is associated with high cholesterol levels, regardless of the children's weight class, while weight excess identifies subjects with the typical lipid profile of metabolic syndrome. What is Known: • Few data are available on the lipid profile in Italian children. • Early treatment of hypercholesterolemia is effective in reducing cardiovascular events later in life; there is no agreement on how to screen for dyslipidemia in childhood, however. What is New: • In a large sample of Italian children, familiarity doubles the risk of hypercholesterolemia, while increased BMI is associated with low HDL cholesterol levels and hypertriglyceridemia. • The pediatrician may perform an assessment of plasma lipids in his office as a first step to diagnose familial hypercholesterolemia.

Eight-week hempseed oil intervention improves the fatty acid composition of erythrocyte phospholipids and the omega-3 index, but does not affect the lipid profile in children and adolescents with primary hyperlipidemia.

Children affected by primary hyperlipidemia have a high risk of developing cardiovascular diseases (CVDs) during adulthood. Several studies have reported a positive association between the intake of polyunsaturated fatty acids (PUFAs) and improvements in lipid markers and CVD risk. Dietary supplements may represent a potential strategy in the management of hyperlipidemia. In this context, the effectiveness of hempseed oil (HSO) rich in PUFAs (particularly linoleic acid (LA) and α-linolenic acid (ALA)) in the modulation of hyperlipidemia has been poorly investigated. The present pilot study aimed to explore the impact of HSO supplementation on the serum lipid profile and fatty acid (FA) composition of red blood cells (RBCs) in children and adolescents with primary hyperlipidemia. A randomized, 8 week long, parallel dietary intervention study was performed. Thirty-six hyperlipidemic probands (6-16 years) on diet therapy were randomized into two groups: the HSO group, receiving 3 g of HSO providing 1.4 g of LA and 0.7 g/day of ALA, and the control group. Both groups received specific dietary guidelines. Before and after the intervention, blood samples were collected and the serum lipid profile, FA composition of RBCs and omega-3-index were analyzed. Eight weeks of supplementation with HSO significantly (p < .01) reduced the RBC content of total saturated and monounsaturated FAs (-5.02 ±â€¯7.94% and - 2.12 ±â€¯2.23%, respectively), increased the levels of total n-3 and n-6 PUFAs (+1.57 ±â€¯1.96% and + 5.39 ±â€¯7.18%, respectively) and the omega-3 index (+1.18 ±â€¯1.42%), but failed to affect the serum lipid profile compared to the control group. In conclusion, our findings seem to support the contribution of HSO supplementation in improving the RBC phospholipid composition and omega-3 index, while no effect was observed regarding modulation of the lipid profile. Further controlled studies are necessary to achieve a complete understanding of the effects of HSO in the modulation of hyperlipidemia and CVD risk in this and other target groups.

Lipid profile and genetic status in a familial hypercholesterolemia pediatric population: exploring the LDL/HDL ratio.

Background Familial hypercholesterolemia (FH) is a genetic disorder caused by mutations in genes involved in low-density lipoprotein (LDL) uptake (LDLR, APOB and PCSK9). Genetic diagnosis is particularly useful in asymptomatic children allowing for the detection of definite FH patients. Furthermore, defining their genetic status may be of considerable importance as the compound heterozygous status is much more severe than the heterozygous one. Our study aims at depicting the genetic background of an Italian pediatric population with FH focusing on the correlation between lipid profile and genetic status. Methods Out of 196 patients with clinically suspected FH (LDL-cholesterol [LDL-C] levels above 3.37 mmol/L, cholesterol level above 6.46 mmol/L in a first-degree relative or the presence of premature cardiovascular acute disease in a first/second-degree relative), we screened 164 index cases for mutations in the LDLR, APOB and PCSK9 genes. Results Patients with mutations (129/164) showed increased levels of LDL-C, 95th percentile-adjusted LDL-C and LDL/high-density lipoprotein (HDL) ratio and decreased levels of HDL-C, adjusted HDL-C. The association of the LDL/HDL ratio with the presence of mutations was assessed independently of age, (body mass index) BMI, parental hypercholesterolemia, premature coronary artery disease (CAD), triglycerides by multivariate logistic regression (odds ratio [OR]=1.701 [1.103-2.621], p=0.016). The LDL/HDL ratio gradually increased from patients without mutations to patients with missense mutations, null mutations and compound heterozygotes. Conclusions In conclusion, the LDL/HDL ratio proved to be a better parameter than LDL-C for discriminating patients with from patients without mutations across different genetic statuses.

Effect of short-term hazelnut consumption on DNA damage and oxidized LDL in children and adolescents with primary hyperlipidemia: a randomized controlled trial.

Children with primary hyperlipidemia are prone to develop premature atherosclerosis, possibly associated with increased oxidative stress. Nutritional therapy is the primary strategy in the treatment of hyperlipidemia and associated conditions. Dietary interventions with bioactive-rich foods, such as nuts, may contribute to the modulation of both lipid profile and the oxidative/antioxidant status. Our study aimed to assess the impact of a dietary intervention with hazelnuts on selected oxidative stress markers in children and adolescents with primary hyperlipidemia. A single-blind, 8-week, randomized, controlled, three-arm, parallel-group study was performed. Children and adolescents diagnosed with primary hyperlipidemia (n=60) received dietary guidelines and were randomized into three groups: group 1 received hazelnuts with skin (HZN+S), and group 2 hazelnuts without skin (HZN-S), at equivalent doses (15-30 g/day, based on body weight); group 3 (controls) received only dietary recommendations (no nuts). At baseline and after 8 weeks, plasma oxidized low-density lipoprotein (ox-LDL) concentrations, oxidative levels of DNA damage in PBMCs and potential correlation with changes in serum lipids were examined. A reduction of endogenous DNA damage by 18.9%±51.3% (P=.002) and 23.1%±47.9% (P=.007) was observed after HZN+S and HZN-S, respectively. Oxidatively induced DNA strand breaks decreased by 16.0%±38.2% (P=.02) following HZN+S treatment. Ox-LDL levels did not change after HZN+S intervention but positively correlated with total cholesterol and LDL cholesterol. A short-term hazelnut intervention improves cell DNA protection and resistance against oxidative stress but not ox-LDL in hyperlipidemic pediatric patients. The trial was registered at ISRCTN.com, ID no. ISRCTN12261900.

Evidence of dysbiosis in the intestinal microbial ecosystem of children and adolescents with primary hyperlipidemia and the potential role of regular hazelnut intake.

Hyperlipidemia starts at a pediatric age and represents an unquestionable risk factor for cardiovascular disease. Modulation of the intestinal microbial ecosystem (IME), in principle, can ameliorate lipid profiles. In this study, we characterized the IME of children and adolescents with primary hyperlipidemia by analyzing fecal samples through 16S rRNA gene profiling (n = 15) and short chain fatty acid (SCFA) quantification (n = 32). The same analyses were also carried out on age-matched normolipidemic controls (n = 15). Moreover, we evaluated the modulatory effect of regular hazelnut intake (approximately 0.43 g of hazelnuts with skin per kg of body weight) on the IME of 15 children and adolescents with hyperlipidemia for eight weeks. We found alterations of numerous operational taxonomic units potentially associated with SCFA-producing bacteria and reductions in the fecal levels of acetate, butyrate and propionate in hyperlipidemic subjects. Furthermore, we observed that an eight-week hazelnut intervention may induce limited changes in fecal microbiota composition but can significantly modulate the fecal levels of predominant intestinal SCFAs, such as acetate. Finally, correlation analyses indicated that changes in lipidemic parameters are linked to modifications of the abundance of specific bacterial taxa, such as the families Lachnospiraceae and Ruminococcaceae and the genera Akkermansia, Bacteroides, Roseburia, and Faecalibacterium. This study suggests that children and adolescents with primary hyperlipidemia possess an altered IME. The promising results presented here support the need for future dietary interventions aimed at positively modulating the IME of hyperlipidemic subjects.

Effect of hazelnut on serum lipid profile and fatty acid composition of erythrocyte phospholipids in children and adolescents with primary hyperlipidemia: A randomized controlled trial.

BACKGROUND & AIM: Regular intake of nuts improves lipid profile and thus reduces the cardiovascular (CV) risk associated with hyperlipidemia. The aim of the study was to investigate the effect of a dietary intervention with hazelnuts (HZNs, 15-30 g/day, depending on patient weight) on serum lipid profile, anthropometric parameters and fatty acids (FAs) composition of erythrocyte phospholipids in children and adolescents with primary hyperlipidemia. METHODS: Eight-week randomized, single blind, controlled, three-arm, parallel-group study. Sixty-six subjects were enrolled and randomized in 3 groups receiving: 1) hazelnuts with skin (HZN+S); 2) hazelnuts without skin (HZN-S); 3) dietary advices for hyperlipidemia only (controls). Before and after intervention, clinical parameters were measured and blood samples were collected for the evaluation of serum lipid levels and phospholipid FA composition of erythrocytes. RESULTS: Two-way ANOVA showed a significant effect of time on serum low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C)/LDL-C ratio and non-HDL-C (p ≤ 0.001), but not of treatment and time × treatment interaction. In particular, HZN+S and HZN-S significantly reduced the concentrations of LDL-C and increased HDL-C/LDL-C ratio. HZNs also had a favorable impact on FAs composition of erythrocyte phospholipids, as demonstrated by time × treatment interaction, with a significant increase of monounsaturated fatty acids (MUFAs) (p = 0.008) and MUFAs/saturated fatty acids (SFAs) ratio (p = 0.002) with respect to the control group. CONCLUSIONS: For the first time, we documented a positive effect of HZN consumption on lipid profile and FA composition of erythrocyte phospholipids in children with primary hyperlipidemia. Further studies are encouraged to better define HZN impact on the markers of CV risk in this population. The trial was registered under ISRCTN.com, ID no. ISRCTN12261900.

Identification and in vitro characterization of two new PCSK9 Gain of Function variants found in patients with Familial Hypercholesterolemia.

Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by pathogenic variants in genes encoding for LDL receptor (LDLR), Apolipoprotein B and Proprotein convertase subtilisin/kexin type 9 (PCSK9). Among PCSK9 variants, only Gain-of- Function (GOF) variants lead to FH. Greater attention should be paid to the classification of variants as pathogenic. Two hundred sixty nine patients with a clinical suspect of FH were screened for variants in LDLR and the patients without pathogenic variants were screened for variants in PCSK9 and APOB. Functional characterization of PCSK9 variants was performed by assessment of protein secretion, of LDLR activity in presence of PCSK9 variant proteins as well as of the LDLR affinity of the PCSK9 variants. Among 81 patients without pathogenic variants in LDLR, 7 PCSK9 heterozygotes were found, 4 of whom were carriers of variants whose role in FH pathogenesis is still unknown. Functional characterization revealed that two variants (p.(Ser636Arg) and p.(Arg357Cys)) were GOF variants. In Conclusions, we demonstrated a GOF effect of 2 PCSK9 variants that can be considered as FH-causative variants. The study highlights the important role played by functional characterization in integrating diagnostic procedures when the pathogenicity of new variants has not been previously demonstrated.

Neonatal screening for biotinidase deficiency: A 30-year single center experience.

We reviewed the outcome of newborn screening for biotinidase deficiency performed at our department since 1987. Among 1,097,894 newborns screened, 461 were recalled, and 18 were identified as affected by complete or partial biotinidase deficiency (incidence 1:61,000, false positive rate 0.04%). The common missense mutation Q456H was found in 80% of patients with profound biotinidase deficiency. Of them, one patient harbored the novel mutation M399I in compound heterozygosity (M399I/Q456H). The complex allele A171T/D444H in cis was found in two patients with profound biotinidase deficiency (in homozygosity and in compound heterozygosity with the R211H mutation, respectively) and in one patient with partial biotinidase deficiency (in compound heterozygosity with the protective allele D444H in trans). All detected patients were treated and followed up at our Center until present. Biotin therapy (10-20 mg/day) allowed the full prevention of clinical symptoms in all patients with no adverse effects. These excellent outcomes confirm that newborn screening for biotinidase deficiency is a very effective secondary prevention program.

Serum lipid profile and fatty acid composition of erythrocyte phospholipids in children and adolescents with primary hyperlipidemia.

This study aimed at characterizing the fatty acid (FA) composition of red blood cell (RBC) phospholipids in children and adolescents with primary hyperlipidemia, and to ascertain potential association with serum lipid profile and dietary factors. At this purpose, 54 probands aged 6-17 years were recruited. Subjects showed a low omega-3 index (eicosapentaenoic acid, EPA + docosahexaenoic acid, DHA <4%). Compared to males, females had a trend toward lower levels of total monounsaturated fatty acids (MUFA) and MUFA/saturated fatty acids (SFAs) ratio in RBCs. An inverse relationship between MUFA concentration in RBCs and serum cholesterol or HDL-C/triglycerides ratio was found. Omega-6 polyunsaturated fatty acids (n-6 PUFA) were positively associated to serum HDL-C levels, and inversely to dietary cholesterol. Fiber intake was positively associated with MUFA/SFA ratio. In conclusion, we provide the first experimental data on phospholipid FA composition of RBCs in hyperlipidemic children, showing sex differences and an overall low omega 3-index.

Lysosomal Acid Lipase Deficiency: Could Dyslipidemia Drive the Diagnosis?

LAL-deficiency (LAL-D) is a rare and systemic condition, secondary to LIPA gene mutations, responsible for lysosomal accumulation of cholesteryl esters and triglycerides, whose manifestations are very heterogeneous in terms of the age of onset, severity and the type of clinical and radiological manifestations. Dyslipidemia, hepatomegaly and hepatosteatosis with increased levels of transaminases are the most common features. The increased risk of premature atherosclerosis and cardiovascular disorders, secondary to a generalized alteration of lipid profile and lipoprotein dysfunction associated with LAL-D, has been increasingly pointed out. Therefore, medical awareness towards LAL-deficiency should be increased, since this condition has to be considered in the differential diagnosis of pediatric conditions manifested with dyslipidemia and hepatic accumulation of intracellular products. On the other hand, early patient identification and management remain challenging.

Rapid progression and mortality of lysosomal acid lipase deficiency presenting in infants.

PURPOSE: The purpose of this study was to enhance understanding of lysosomal acid lipase deficiency (LALD) in infancy. METHODS: Investigators reviewed medical records of infants with LALD and summarized data for the overall population and for patients with and without early growth failure (GF). Kaplan-Meier survival analyses were conducted for the overall population and for treated and untreated patients. RESULTS: Records for 35 patients, 26 with early GF, were analyzed. Prominent symptom manifestations included vomiting, diarrhea, and steatorrhea. Median age at death was 3.7 months; estimated probability of survival past age 12 months was 0.114 (95% confidence interval (CI): 0.009-0.220). Among patients with early GF, median age at death was 3.5 months; estimated probability of survival past age 12 months was 0.038 (95% CI: 0.000-0.112). Treated patients (hematopoietic stem cell transplant (HSCT), n = 9; HSCT and liver transplant, n = 1) in the overall population and the early GF subset survived longer than untreated patients, but survival was still poor (median age at death, 8.6 months). CONCLUSIONS: These data confirm and expand earlier insights on the progression and course of LALD presenting in infancy. Despite variations in the nature, onset, and severity of clinical manifestations, and treatment attempts, clinical outcome was poor.Genet Med 18 5, 452-458.

Cholesterol trafficking-related serum lipoprotein functions in children with cholesteryl ester storage disease.

OBJECTIVE: Serum lipoproteins influence cell cholesterol content by delivering and removing cholesterol to/from cells, functions mainly exerted by LDL and HDL, respectively. Especially in the case of HDL, structure and composition are crucial for function, beyond serum levels. Cholesteryl ester storage disease (CESD) is caused by LIPA gene mutations and reduced activity of lysosomal acid lipase (LAL), the enzyme responsible for hydrolysis of cholesteryl esters and TG. CESD patients typically present dyslipidaemia, liver damage and premature atherosclerosis. The objective of this work was to evaluate serum HDL cholesterol efflux capacity (CEC) and serum cholesterol loading capacity (CLC) in CESD pediatric patients and to study lipoprotein qualitative modifications. METHODS: HDL CEC was evaluated by radioisotopic techniques, serum CLC was measured by a fluorimetric assay, HDL subclasses were determined by two-dimensional electrophoresis. RESULTS: CESD patients (n = 3) displayed on average increased LDL cholesterol (+163%; p = 0.019), TG (+203; p = 0.012), phospholipids (+40%; p = 0.024) and lower HDL cholesterol (-57%; p = 0.012) compared to controls (n = 9). CESD HDL CEC was impaired both as a whole (average reduction of 26%; p < 0.0001) and with respect to specific membrane cholesterol transporters (-23% for aqueous diffusion; p = 0.005; -32% for ABCA1-efflux; p = 0.0002; -60% for SR-BI-efflux; p < 0.0001; -42% for ABCG1-efflux p = 0.0003). A marked reduction in the pre-ß HDL concentration (-69%; p = 0.012) was detected. Finally, CESD serum CLC was significantly increased (+21%; p = 0.0007). CONCLUSION: These new data demonstrate that the pro-atherogenic modifications of serum include disturbances in lipoprotein functions involved in cell cholesterol homeostasis occurring from very early age in CESD patients.

Clinical Features of Lysosomal Acid Lipase Deficiency.

OBJECTIVE: The aim of this study was to characterize key clinical manifestations of lysosomal acid lipase deficiency (LAL D) in children and adults. METHODS: Investigators reviewed medical records of LAL D patients ages ≥5 years, extracted historical data, and obtained prospective laboratory and imaging data on living patients to develop a longitudinal dataset. RESULTS: A total of 49 patients were enrolled; 48 had confirmed LAL D. Mean age at first disease-related abnormality was 9.0 years (range 0-42); mean age at diagnosis was 15.2 years (range 1-46). Twenty-nine (60%) were male patients, and 27 (56%) were <20 years of age at the time of consent/assent. Serum transaminases were elevated in most patients with 458 of 499 (92%) of alanine aminotransferase values and 265 of 448 (59%) of aspartate aminotransferase values above the upper limit of normal. Most patients had elevated low-density lipoprotein (64% patients) and total cholesterol (63%) at baseline despite most being on lipid-lowering therapies, and 44% had high-density lipoprotein levels below the lower limit of normal. More than half of the patients with liver biopsies (n = 31, mean age 13 years) had documented evidence of steatosis (87%) and/or fibrosis (52%). Imaging assessments revealed that the median liver volume was ∼1.15 multiples of normal (MN) and median spleen volume was ∼2.2 MN. Six (13%) patients had undergone a liver transplant (ages 9-43.5 years). CONCLUSION: This study provides the largest longitudinal case review of patients with LAL D and confirms that LAL D is predominantly a pediatric disease causing early and progressive hepatic dysfunction associated with dyslipidemia that often leads to liver failure and transplantation.