Homozygous familial hypercholesterolaemia (HoFH) is a rare genetic disorder marked by extremely elevated low-density lipoprotein cholesterol (LDL-C) levels from birth and a very high risk of premature atherosclerotic cardiovascular disease (ASCVD). To address the global paucity of observational data, the HoFH International Clinical Collaborators (HICC) registry (NCT04815005) was established. To date, over 950 HoFH individuals from 45 countries have been included. The median age at diagnosis was 12 years (IQR: 5.5-27.0), and untreated LDL-C levels were markedly elevated [median 14.7 mmol/L (11.6-18.4)]. At diagnosis, 9% had ASCVD or (supra)aortic valve disease, and despite the widespread use of lipid-lowering therapy (LLT), only 4% achieved guideline-recommended LDL-C goals. Early initiation of lipoprotein-apheresis was associated with greater LDL-C reductions and delayed ASCVD onset. Cardiovascular burden remains substantial, with a median age at death of 37 years [20-50]. No sex differences were observed in age or clinical characteristics at diagnosis, treatment patterns, or timing of ASCVD, although the usual sex gap in cardiovascular disease onset was absent. Profound global disparities persist, including limited genetic screening, restricted access to LLT, and earlier onset of major adverse cardiovascular events in non-high-income countries. Reproductive care for women remains highly variable and understudied. The HICC aims to guide global stakeholders in improving clinical outcomes for individuals with HoFH through earlier diagnosis, equitable access to advanced therapies, and broader inclusion of underserved regions. By generating evidence from routine clinical care and patient-reported data, identifying gaps in care, and fostering international collaboration, HICC seeks to advance a more equitable and effective global approach to HoFH management.

Solid-organ transplantation and related medical treatments can significantly alter the gut microbiome. While disruptions in bacterial communities (dysbiosis) have been associated with infections, rejection, and increased mortality in transplant recipients, research on gut fungal communities (the mycobiome) remains limited. To our knowledge, no study has yet concurrently characterized the bacterial and fungal microbiota or quantified the fungal load longitudinally in patients following solid-organ transplantation. This study aimed to describe temporal changes in these microbial communities and explore associations with clinical outcomes. We analysed the gut microbiota dynamics in 21 solid-organ transplant recipients and 10 healthy volunteers across six timepoints, processing 184 samples using both bacterial (16 S rRNA) and fungal (ITS) amplicon sequencing. Bacterial diversity significantly decreased shortly after transplantation but partially recovered during the later post-transplant phase. In contrast, fungal diversity was consistently lower after transplantation and showed greater temporal variability. Quantitative PCR revealed a transient increase in the fungal load at approximately two weeks post-transplant, which was negatively correlated with bacterial diversity. Patients who experienced clinical complications presented reduced microbial richness, especially during the early post-transplant period. Additionally, we identified correlations between selected fungal taxa and bacterial genera previously linked to dysbiosis, suggesting potential interkingdom interactions that may influence microbiome dynamics after transplantation. Our study provides a longitudinal overview of both bacterial and fungal microbiota following solid-organ transplantation. The association between fungal load and bacterial diversity indicates possible interkingdom interactions affecting microbiome recovery, but the clinical implications remain to be elucidated. These findings highlight the importance of including fungal communities alongside bacterial microbiota in future research and clinical monitoring.

BACKGROUND AND AIMS:Familial hypercholesterolemia (FH), primarily caused by pathogenic LDLR, APOB, or PCSK9 variants, results in elevated LDL-C and increased cardiovascular risk. Genetic testing offers the definitive diagnosis, yet global approaches to FH genetic testing remain unstandardized. We investigate current testing practices worldwide and provide relevant recommendations. METHODS:A survey was distributed to national lead-investigators (NLIs) of 68 countries in the FH-Studies Collaboration, assessing referral criteria, assay methodologies, target genes, and pathogenicity interpretation methods. RESULTS:NLIs from centres in 55/68 countries (81%) responded, spanning Africa (N=2), Americas (N=6), Asia (N=20), Europe (N=26), and Oceania (N=1). DLCN scores were the most common reason for referral to genetic testing (adults:72%; children:57%). Simon Broome and MEDPED criteria were reported only by centres from high-income countries (adults: 7% and 2%; children: 12% and 2%). Methods for testing in index versus non-index cases were significantly different (p <0.001). Next-generation sequencing (NGS) was the predominant assay method for index cases (62%), while Sanger sequencing was favoured for non-index (71%). However, these testing techniques did not differ between centres from high- and non-high-income countries for index cases (p=0.74) and non-index cases (p=0.49). Copy-number variants (CNVs) were assessed by 65% of centres, with most integrating CNV analysis into NGS platforms (86%) and others (14%) using multiplex ligation-dependent probe-amplification (MLPA) or microarrays. Screening encompassed LDLR (100%), APOB (97%), PCSK9 (95%), and other genes. Most centres (96%) incorporated pathogenicity interpretation into their reports, adhering largely to American College of Medical Genetics and Genomics guidelines. CONCLUSIONS:FH genetic testing practices vary widely across countries surveyed, emphasizing the need for global standardization to enhance accuracy and comparability of FH diagnoses worldwide. We suggest that genetic testing should include the three FH-causing genes and ideally the five associated/phenocopy genes.

PURPOSE OF REVIEW:Familial hypercholesterolemia is a monogenic Mendelian disorder characterized by elevated LDL cholesterol and premature atherosclerotic cardiovascular disease. It is caused by pathogenic variants in LDLR , APOB , and PCSK9 , with rarer involvement of LDLRAP1 and APOE . Despite advances in molecular diagnostics, no causative variant is identified in approximately 25-75% of clinically diagnosed cases. RECENT FINDINGS:Familial hypercholesterolemia is currently defined as an autosomal semi-dominant disorder with a gene-dosage effect, whereby biallelic pathogenic variants result in markedly more severe phenotypes than heterozygous variants. Terminology for homozygous familial hypercholesterolemia has been refined. Former terms such as 'true homozygote', 'compound heterozygote', and 'double heterozygotes' have been replaced by monogenic biallelic forms, with identical or different variants, and digenic biallelic forms involving two familial hypercholesterolemia-associated genes. Polygenic risk score (PRS) and lipoprotein(a) measurement help explain familial hypercholesterolemia-like phenotypes in patients without a monogenic cause and enable determination of polygenic severe hypercholesterolemia and/or hyperlipoproteinemia(a). Although advances in molecular genetics have improved variant detection, interpretation remains challenging. Integration of case-level data and functional studies, including high-throughput LDLR assays and APOB structural analyses, has enhanced variant pathogenicity classification. SUMMARY:Combining monogenic variant detection, PRS determination and lipoprotein(a) assessment enables comprehensive diagnosis, tailored risk stratification, and personalized familial hypercholesterolemia management.

Familial hypercholesterolaemia (FH) is a common genetic disorder characterized by lifelong elevated LDL cholesterol (LDL-C) concentrations. FH exists in two forms: heterozygous FH (HeFH), which affects around 1 in 300 people worldwide, and homozygous FH (HoFH), which affects around 1 in 300 000. Individuals with FH are at increased risk of premature atherosclerotic cardiovascular disease (ASCVD) and death, and those with HoFH are, if untreated, at extreme risk of ASCVD manifestations even before adulthood. Early diagnosis and treatment in childhood can extend or normalize life expectancy, but limited awareness, underdiagnosis, and undertreatment remain major challenges. This consensus statement aims to address these challenges, supported by increased knowledge of the pathogenesis of FH and the availability of an increasing range of lipid-lowering therapies (LLTs) that can be used from early ages. To increase the detection rate of FH, all countries are encouraged to establish a paediatric screening programme and, given that current diagnostic criteria often fail to identify children with an FH-causing genetic variant, revised diagnostic criteria are presented. Updated LDL-C treatment goals are proposed, and the importance of starting LLTs before puberty in children with HeFH, and, if needed, from 6 years, is highlighted. Guidance on how to manage FH is provided, including treatment algorithms for use in children with either HeFH or HoFH and a discussion on how to promote a smooth transition to adult care. Early detection and optimal treatment as advocated in this consensus statement are crucial to improving life expectancy for children and adolescents with FH.

Background/Synopsis Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder characterized by markedly elevated low-density lipoprotein cholesterol (LDL-C) and atherosclerotic cardiovascular disease (ASCVD) with onset in childhood. Early initiation of lipid-lowering treatment is associated with improved clinical outcomes. However, data on the management of very young children (≤5 years) diagnosed with HoFH remain limited. Objective/Purpose To assess current management practices and identify challenges in treating HoFH patients 5 years or younger. Methods An online survey was sent to clinicians through the HoFH International Clinical Collaborators (HICC) consortium and via personal contacts and professional networking. The survey addressed current management strategies for very young HoFH patients, preferred approaches under conditions of unrestricted access to resources, and perspectives on newborn screening. Results Forty-eight clinicians across 17 countries reported direct experience treating 194 HoFH patients ≤5 years. Seventy-five percent reported initiating treatment within 4 weeks of diagnosis. Based on current access to therapies, 60% used statin, 21% evinacumab, and 11% lifestyle and diet as first-line treatment. In a hypothetical scenario of unrestricted access, 40% of clinicians would use evinacumab as first-line. Inclusion of HoFH in newborn screening was supported by 88% of surveyed clinicians; 94% were comfortable establishing the diagnosis and 71% were comfortable managing treatment following a positive screening result. Conclusions Statins are currently used as first-line treatment in very young HoFH patients by the majority of clinicians; however, many would ideally prescribe evinacumab, now approved by the Food and Drug Administration (FDA) and European Medicines Agency (EMA) for use in infants. The findings also demonstrate strong support for newborn screening of HoFH.

Aims Familial hypercholesterolaemia (FH), primarily caused by pathogenic LDLR, APOB, or PCSK9 variants, results in elevated LDL cholesterol and increased cardiovascular risk. Genetic testing offers the definitive diagnosis, yet global approaches to FH genetic testing remain unstandardized. We investigate current testing practices worldwide and provide relevant recommendations. Methods and results A survey was distributed to national lead investigators of 68 countries in the Familial Hypercholesterolaemia Studies Collaboration, assessing referral criteria, assay methodologies, target genes, and pathogenicity interpretation methods. National lead investigators from centres in 55/68 countries (81%) responded, spanning Africa (n = 2), Americas (n = 6), Asia (n = 20), Europe (n = 26), and Oceania (n = 1). Dutch Lipid Clinic Network (DLCN) scores were the most common reason for referral to genetic testing (adults, 72%; children, 57%). Simon-Broome and Make Early Diagnosis to Prevent Early Death (MEDPED) criteria were reported only by centres from high-income countries (adults, 7% and 2%; children, 12% and 2%). Methods for testing in index vs. non-index cases were significantly different (P < 0.001). Next-generation sequencing (NGS) was the predominant assay method for index cases (62%), while Sanger sequencing was favoured for non-index (71%). However, these testing techniques did not differ between centres from high- and non-high-income countries for index cases (P = 0.74) and non-index cases (P = 0.49). Copy-number variants (CNVs) were assessed by 65% of centres, with most integrating CNV analysis into NGS platforms (86%) and others (14%) using multiplex ligation-dependent probe amplification (MLPA) or microarrays. Screening encompassed LDLR (100%), APOB (97%), PCSK9 (95%), and other genes. Most centres (96%) incorporated pathogenicity interpretation into their reports, adhering largely to American College of Medical Genetics and Genomics guidelines. Conclusion Familial hypercholesterolaemia genetic testing practices vary widely across countries surveyed, emphasizing the need for global standardization to enhance accuracy and comparability of FH diagnoses worldwide. We suggest that genetic testing should include the three FH-causing genes and ideally the five associated/phenocopy genes.

Because one in three of all individuals die from atherosclerotic cardiovascular disease (ASCVD), prevention of ASCVD is key to public health worldwide. Lipid clinics provide specialized diagnostic assessment, lifestyle management, and evidence-based lipid-lowering treatment to prevent ASCVD and acute pancreatitis in high-risk individuals. This includes individuals with familial hypercholesterolemia and/or markedly increased lipoprotein(a), statin intolerance, refractory or difficult-to-control low-density lipoprotein (LDL) cholesterol, severe hypertriglyceridaemia, and other rare or complex lipid disorders. Such specialized care not only benefits the individual patients and their families but facilitates dissemination of best practices in lipid disorder management to healthcare professionals in individual nations. Despite this, there is a lack of guidance on standards and metrics needed to establish a well-harmonized national lipid clinic network in most countries capable of offering comprehensive care. This consensus paper from the European Atherosclerosis Society Lipid Clinic Network aims to meet this unmet clinical need. We provide recommendations to enhance education and training on lipid disorders and to harmonize lipid clinics at both national and international levels. Furthermore, we provide guidance on optimal staffing structures and development of registries to improve diagnosis and management of lipid disorders. Finally, we offer recommendations to national and regional policymakers on funding of lipid clinics, with the long-term goal of reducing the overall societal burden and costs of cardiovascular and other lipid-related diseases.

BACKGROUND AND AIMS:Women with familial hypercholesterolaemia (FH) lose substantial treatment time during their reproductive years as most lipid-lowering therapies are contraindicated from the preconception through the end of breastfeeding. We examined the duration of real-life pregnancy-related off-treatment time in 27 women with FH in Norway. METHODS:Women with FH in Norway who had completed the ongoing FH-FEMINA study (ClinicalTrials.gov ID NCT05367310) were included. Women were followed from 36th week of gestation and until one year after delivery or until end of breastfeeding. Information on use of medication before, during and after the current and previous pregnancies was collected. Pregnancy-related off-treatment time was calculated from discontinuation of lipid-lowering therapy when planning pregnancy, throughout pregnancy, and after delivery. RESULTS:The total duration of pregnancy-related off-treatment time after all childbirths (median 1, range 1-3) per woman was a median of 2.9 years (25th-75th percentile; 1.6-4.0), ranging from 0.8 to 12 years. The pregnancy itself accounted for median of 42.1% of the pregnancy-related off-treatment time, whereas the time before and after pregnancy accounted for a median of 57.9% (range 11.4% to 91.2%). When including untreated years in childhood and/or prior to diagnosis, the lifelong off-treatment time represented a median of 66.3% (range 41.9 to 100%) of lifetime without treatment. CONCLUSION:Early diagnosis and initiation of treatment is essential in girls with FH to compensate for pregnancy-related off-treatment time later in life. To minimize these pregnancy-related off-treatment periods, healthcare professionals should support women with FH to resume lipid-lowering therapy immediately after breastfeeding and between pregnancies. In addition, more knowledge on the potential effects of statin use during pregnancy and breastfeeding on maternal and offspring health is urgently needed.

Aims Familial hypercholesterolemia (FH) significantly increases cardiovascular risk from childhood yet remains widely underdiagnosed. This cross-sectional study aimed to evaluate existing paediatric FH diagnostic criteria in real-world cohorts and to develop two novel diagnostic tools: a semi-quantitative scoring system (FH-PeDS) and a machine learning model (ML-FH-PeDS) to enhance early FH detection. Methods and results Five established FH diagnostic criteria were assessed (Dutch Lipid Clinics Network [DLCN], Simon Broome, EAS, Simplified Canadian, and Japanese Atherosclerosis Society) in Slovenian (N = 1360) and Portuguese (N = 340) paediatric hypercholesterolemia cohorts, using FH-causing variants as the reference standard. FH-PeDS was developed from the Slovenian cohort, and ML-FH-PeDS was trained and tested using a 60%/40% split before external validation in the Portuguese cohort. Only 47.4% of genetically confirmed FH cases were identified by all established criteria, while 10.9% were missed entirely. FH-PeDS outperformed DLCN in the combined cohort (AUC 0.897 vs. 0.857; P < 0.01). ML-FH-PeDS showed superior predictive power (AUC 0.932 in training, 0.904 in testing vs. 0.852 for DLCN; P < 0.01) and performed best as a confirmatory test in the testing subgroup (39.7% sensitivity, 87.7% PPV at 98% specificity). In the Portuguese cohort, ML-FH-PeDS maintained strong predictive performance (AUC 0.867 vs. 0.815 for DLCN; P < 0.01) despite population differences. Conclusion Current FH diagnostic criteria perform sub-optimally in children. FH-PeDS and ML-FH-PeDS provide tools to improve FH detection, particularly where genetic testing is limited. They also help guide genetic testing decisions for hypercholesterolemic children. By enabling earlier diagnosis and intervention, these tools may reduce long-term cardiovascular risk and improve outcomes.

Lipodystrophic syndromes are a heterogeneous group of disorders characterized by a lack of fatty tissue or abnormal fat accumulation outside of the body's typical fat distribution areas. Partial lipodystrophy most commonly manifests in childhood or young adulthood, and is classified into 6 primary subtypes, along with other rare categories. Lipodystrophy subtype 4 is associated with severe insulin resistance and unique traits, including severe hyperlipidemia, progressive liver disease, and arterial hypertension. Here we present the case of a 30-year-old woman with alarming hypertriglyceridemia, newly diagnosed diabetes mellitus, and severe hypertension. A complex differential diagnostic procedure yielded the diagnosis of familial partial lipodystrophy subtype 4. Initial treatment with plasmapheresis effectively reduced her triglyceride values but failed due to lack of intravenous access. Recurrent severe hypertriglyceridemia and normal leptin levels prompted the use of volanesorsen therapy, which is primarily indicated for treatment of hypertriglyceridemia in familial chylomicronemia syndrome. Volanesorsen proved very effective in this case.

BACKGROUND:Severe combined immunodeficiency (SCID) is a fatal but treatable inborn error of immunity (IEI). Newborn screening (NBS) using T-cell receptor excision circles (TREC) has been adopted globally, with very few countries incorporating kappa recombination excision circles (KREC) to also detect early B-cell development disorders, such as X-linked agammaglobulinemia (XLA). OBJECTIVE:To evaluate the effectiveness of a 2-year pilot SCID NBS program in the Czech Republic, emphasising the utility of combined TREC/KREC screening. METHODS:Between January 2022 and December 2023, a dual TREC/KREC NBS pilot was conducted across the Czech Republic, alongside spinal muscular atrophy (SMA) screening. Approximately 200,000 newborns were screened using quantitative real-time PCR on dried blood spots collected 48-72 h after birth. RESULTS:The pilot referred 58 newborns, identifying 21 cases of IEI, including two SCID cases, with an overall incidence of TREC/KREC screenable IEI of 10.5/100,000 newborns. SCID incidence was 1/100,000. KREC screening proved invaluable, detecting 10 cases of congenital agammaglobulinemia including novel non-XLA forms, which increased the estimated incidence of agammaglobulinemia in the Czech Republic sixfold. Over one-third of low KREC results were linked to maternal immunosuppression. CONCLUSION:The Czech pilot demonstrated the effectiveness of integrated TREC/KREC NBS in detecting both T- and B-cell immunodeficiencies. As of 2024, SCID and SMA screening are included in the nationwide NBS, with KREC screening significantly improving early detection of B-cell disorders.

BACKGROUND AND AIMS:Overweight and obesity are modifiable risk factors for atherosclerotic cardiovascular disease (ASCVD) in the general population, but their prevalence in individuals with heterozygous familial hypercholesterolaemia (HeFH) and whether they confer additional risk of ASCVD independent of LDL cholesterol (LDL-C) remains unclear. METHODS:Cross-sectional analysis was conducted in 35 540 patients with HeFH across 50 countries, in the EAS FH Studies Collaboration registry. Prevalence of World Health Organization-defined body mass index categories was investigated in adults (n = 29 265) and children/adolescents (n = 6275); and their association with prevalent ASCVD. RESULTS:Globally, 52% of adults and 27% of children with HeFH were overweight or obese, with the highest prevalence noted in Northern Africa/Western Asia. A higher overweight/obesity prevalence was found in non-high-income vs. high-income countries. Median age at familial hypercholesterolaemia diagnosis in adults with obesity was 9 years older than in normal weight adults. Obesity was associated with a more atherogenic lipid profile independent of lipid-lowering medication. Prevalence of coronary artery disease increased progressively across body mass index categories in both children and adults. Compared with normal weight, obesity was associated with higher odds of coronary artery disease in children (odds ratio 9.28, 95% confidence interval 1.77-48.77, adjusted for age, sex, lipids, and lipid-lowering medication) and coronary artery disease and stroke in adults (odds ratio 2.35, 95% confidence interval 2.10-2.63 and odds ratio 1.65, 95% confidence interval 1.27-2.14, respectively), but less consistently with peripheral artery disease. Adjusting for diabetes, hypertension and smoking modestly attenuated the associations. CONCLUSIONS:Overweight and obesity are common in patients with HeFH and contribute to ASCVD risk from childhood, independent of LDL-C and lipid-lowering medication. Sustained body weight management is needed to reduce the risk of ASCVD in HeFH.

Familial hypercholesterolemia (FH) is a disorder of cholesterol metabolism characterized by elevated LDL-cholesterol levels. The most common cause of FH is pathogenic variants in the LDL receptor (LDLR) gene. To shed light on the functional impact of selected LDLR variants, we functionally characterized 16 LDLR genetic variants alongside 10 control variants. We performed in vitro assays based on transient expression of WT and mutant LDLRs in LDLR-deficient Chinese hamster ovary cells. We used flow cytometry to analyze the relative amount of LDLRs expressed on the cell surface and the relative amount of internalized LDL. In addition, we analyzed the expression and maturation of LDLR protein by Western blotting. Of the 16 studied variants, two variants (p.(Asn272Thr) and p.(Arg574Leu)) did not exhibit a defect in LDLR function, one variant (p.(Ala540Thr)) exhibited a defect in LDL binding and/or internalization despite normal LDLR cell surface expression, and the remaining 13 variants had a detrimental effect on both LDLR cell surface expression and LDL internalization. The information presented in this study contributes to the clinical classification of LDLR variants and a more precise diagnosis of FH patients, highlighting the type of defect each variant produces.