Genotypic and phenotypic features of dyslipidemia in a sample of pediatric patients in China.

BACKGROUND: Dyslipidemia, especially hypercholesterolemia is of significant clinical interest. Precise diagnosis is not paid enough attention to about the management of pediatric patients with hypercholesterolemia, which is especially apparent in China. Given this, we designed this study to confirm the specific molecular defects associated with hypercholesterolemia using whole-exome sequencing (WES) to be helpful for precise diagnosis and treatment. METHODS: Pediatric patients were enrolled using specific criteria and their clinical information were recorded for later evaluation in conjunction with the WES completed for each of these patients. RESULTS: Our criteria allowed for the initial enrollment of 35 patients, 30 of whom (aged 1.02-12.99 years) underwent successful genetic sequencing and clinical investment. Positive results were obtained in 63.33% (19/30) of these patients. We identified 25 variants in 30 pediatric patients with persistent hypercholesterolemia, seven of them were novel and variants in LDLR and ABCG5/ABCG8 ranks first and second, respectively. Further analysis revealed that the levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (ApoB) and lipoprotein (a) were higher in patients with positive genetic results. CONCLUSION: Our study enriched the genetic and phenotypic spectra for hypercholesterolemia in young patients. Genetic testing is important for the prognostics and treatment of pediatric patients. Heterozygous ABCG5/8 variants may be underestimated in pediatric patients with hypercholesterolemia.

Cerebrotendinous xanthomatosis without neurological involvement.

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is an autosomal recessively inherited inborn error of metabolism. Neurological symptoms are considered to be a clinical hallmark of untreated adult patients. We describe a 'milder CTX phenotype', without neurological involvement. METHODS: We performed a retrospective patient file study in 79 genetically confirmed Dutch patients with CTX (55 patients aged ≥ 21 years) to study the clinical heterogeneity of CTX. We studied the frequency of adult patients with CTX without neurological involvement at diagnosis, in our Dutch cohort, and included a family from South Africa and patients from Italy, USA, Chile and Asia from the literature. RESULTS: In total, we describe 19 adult patients with CTX from 16 independent families, without neurological symptoms at diagnosis. A relatively small percentage (21%, n = 4) had a history of cataract. The majority, 84% (n = 16), presented with tendon xanthomas as the sole or predominant feature. The majority of patients showed increased plasma cholesterol levels. No correlation was found between this 'milder phenotype', the cholestanol levels and the CYP27A1 genotype. In addition, we describe three novel mutations in the CYP27A1 gene. CONCLUSIONS: This study shows the clinical heterogeneity of CTX, highlighting the existence of a 'milder phenotype', that is without neurological involvement at diagnosis. Adult patients with CTX may present with tendon xanthomas as the sole or predominant feature, mimicking familial hypercholesterolemia. It is important to realize that the absence of neurological symptoms does not rule out the development of future neurological symptoms. As CTX is a treatable disorder, early diagnosis and initiation of treatment when additional clinical signs occur is therefore essential.

Relations of physical signs to genotype, lipid and inflammatory markers, coronary stenosis or calcification, and outcomes in patients with heterozygous familial hypercholesterolemia.

BACKGROUND: Although the presence of physical signs [tendon xanthomas and/or corneal arcus (TX/CA)], are associated with the risk of coronary artery disease in patients with heterozygous familial hypercholesterolemia (HeFH), their relationship with genotypes and clinical characteristics has not been fully determined. This study aimed to examine the association of TX/CA with genetic mutation, lipid- and inflammation-related markers, the severity of coronary stenosis or calcification, and cardiovascular events (CVEs) in patients with HeFH. METHODS: LDLR, APOB, and PCSK9 genes were screened in 523 HeFH patients, and patients with TX/CA (n = 50) were 1:4 propensity score-matched to patients without TX/CA (n = 200) to adjust for age and sex. Laboratory markers (proprotein convertase subtilisin/kexin type 9 [PCSK9], lipoprotein(a) and high-sensitivity C-reactive protein [hsCRP]), computed tomography angiography, coronary angiography, and follow-up for CVEs were performed. RESULTS: Patients with physical signs had significantly higher low-density lipoprotein cholesterol levels; higher PCSK9 or hsCRP concentrations; more LDLR positive mutations; and higher prevalence of high tertiles of Gensini, SYNTAX and Jeopardy scores as well as coronary artery calcium scores than did those without. Over an average follow-up of 3.7 years, the incidence of CVEs was significantly higher in patients with TX/CA (log-rank p < 0.001). Patients with physical signs and mutation positivity had threefold higher risks of CVEs (adjusted hazard ratio 3.34, 95% confidence interval 1.04-10.72, p = 0.024). CONCLUSIONS: Physical signs were associated with genotypes and phenotypes, and worse outcomes in patients with HeFH, suggesting that these signs may help in risk stratification in these patients.

Cerebrotendinous Xanthomatosis patients with late diagnosed in single orthopedic clinic: two novel variants in the CYP27A1 gene.

BACKGROUND: Cerebrotendinous Xanthomatosis (CTX) is a rare autosomal recessive lipid storage disorder caused by loss of function variants in the CYP27A1 gene which encodes sterol 27-hydroxylase, on chromosome 2q35. Although the symptoms begin commonly in infancy, CTX diagnosis is often delayed. The aim of this study is to review the orthopedic findings of the disease by providing an overview of the clinical features of the disease. It is to raise awareness of this condition for which early diagnosis and treatment are important. METHODS: We retrospectively evaluated the clinical, laboratory, radiological, and genetic findings of eight patients from four families who were admitted to our Orthopedics and Traumatology Department between 2017 and 2022 due to bilateral Achilles tendon xanthomas, were found to have high cholestanol and CYP27A1 gene mutations. RESULTS: The mean age of patients was 37, and five of them were male. The mean age at the onset of symptoms was 9.25 years. The mean age of initial diagnosis was 33.75 years. Between symptom onset and clinical diagnosis, an average delay of 24.5 years was observed. All patients had bilateral Achilles tendon xanthoma. Notably, a novel variant (c.670_671delAA) in CYP27A1 gene was identified in three patients who also presented with peripheral neuropathy and bilateral pes cavus. One patient had osteoporosis and four patients had osteopenia. Five patients had a history of bilateral cataracts. Furthermore, three of the patients had early-onset chronic diarrhea and three of the patients had ataxia. Two of the patients had epilepsy and seven of the patients had behavior-personality disorder. All patients had low intelligence, but none of them had cardiac disease. CONCLUSION: We present the diagnostic process and clinical features which the largest CTX case series ever reported from single orthopedic clinic. We suggest that patients with normal cholesterol levels presenting with xanthoma being genetically analyzed by testing at their serum cholestanol level, and that all siblings of patients diagnosed with CTX be examined.

Widespread xanthomas regression by personalized lipid lowering therapy in heterozygous familial hypercholesterolemia.

"The lower, the better" is the recommended approach in the management of high LDL cholesterol. Unfortunately, this does not always achieve as in the case of a 69-year-old woman referred to our Institute for her lipid profile (LDL cholesterol 412mg/dl), bilateral xanthelasma and cutaneous xanthomas. With a maximized and personalized lipid-lowering therapies (rosuvastatin, ezetimibe, PCSK9i and lipoprotein apheresis), after only six months, the patient showed an impressive regression in her cutaneous xanthomas.

Factors associated with the presence of tendon xanthomas in familial hypercholesterolemia.

INTRODUCTION AND OBJECTIVES: Tendon xanthomas (TX) are lipid deposits highly specific to familial hypercholesterolemia (FH). However, there is significant variability in their presentation among FH patients, primarily due to largely unknown causes. Lipoprotein(a) is a well-established independent risk factor for atherosclerotic cardiovascular disease in the general population as well as in FH. Given the wide variability of lipoprotein(a) among FH individuals and the likelihood that TX may result from a proatherogenic and proinflammatory condition, the objective of this study was to analyze the size of TX in the Achilles tendons of FH participants and the variables associated with their presence, including lipoprotein(a) concentration. METHODS: A cross-sectional study was conducted on 377 participants with a molecular diagnosis of heterozygous FH. Achilles tendon maximum thickness (ATMT) was measured using ultrasonography with standardized equipment and procedures. Demographic variables and lipid profiles were collected. A multivariate linear regression model using a log-Gaussian approach was used to predict TX size. Classical cardiovascular risk factors and lipoprotein(a) were included as explanatory variables. RESULTS: The mean low-density lipoprotein cholesterol level was 277mg/dL without lipid-lowering treatment, and the median ATMT was 5.50mm. We demonstrated that age, sex, low-density lipoprotein cholesterol, and lipoprotein(a) were independently associated with ATMT. However, these 4 variables did not account for most the interindividual variability observed (R2=0.205). CONCLUSIONS: TX, a characteristic hallmark of FH, exhibit heterogeneity in their presentation. Interindividual variability can partially be explained by age, male sex, low-density lipoprotein cholesterol, and lipoprotein(a) but these factors account for only 20% of this heterogeneity.

Tendon xanthomas as indicators of atherosclerotic burden on coronary arteries.

The presence of tendon xanthomas is an almost certain indicator of familial hypercholesterolemia (FH). They also reflect coronary atherosclerotic burden and therefore must be treated aggressively. Tendon xanthomas also occur in two rare conditions, cerebrotendinous xanthomatosis and sitosterolemia, which are not easily confused with FH, can be easily differentiated with clinical history and biochemical tests.

Achilles Tendon Softness and Thickness in Patients With Hypercholesterolemia.

Background Hypercholesterolemia is a condition where blood levels of cholesterol are high. It is of two types: The first type is familial hypercholesterolemia, which is hereditary, and the second one is due to diseases like diabetes, thyroid, etc. Achilles tendon xanthomas are noted in both types of hypercholesterolemia, which can be used as an indicator that predicts early cardiovascular disease. The aim of the study is to estimate the Achilles tendon thickness (ATT) and softness among hypercholesterolemia patients and to find the correlation between ATT and total cholesterol. Methodology A hospital-based cross-sectional, analytical study was done in a tertiary care hospital, Salem, for eight months. Patients of age over 18 years of both sexes who came for screening of total cholesterol in the outpatient department were included in the study. Those patients with a history of previous leg injury involving the Achilles tendon were excluded from the study. A pre-structured questionnaire was used to collect the data, and analysis was done using Statistical Package for the Social Sciences (SPSS) v20 (IBM Corp., Armonk, NY). The analysts performed the Pearson correlation test to determine the correlation between two continuous variables. A p-value of less than 0.05 was used to indicate statistical significance. Results In this study, there are 40 participants in the normal group and about 60 participants in the secondary hypercholesterolemia group. The mean ATT value among males and females was 9.3 and 6.1 mm, respectively. A positive correlation was noted between the ATT and total cholesterol value (p-value = 0.0001). Conclusion The thickness and softness of the Achilles tendon are positively correlated with the serum total cholesterol level. Males are the group where this correlation is most significant. As a result, men have a higher risk of developing Achilles tendon thickening than women. The thickness of the Achilles tendon can therefore be one of the early signs of high cholesterol levels. The clinician can utilize this indicator to evaluate early abnormal cardiac illness.

The value of physical signs in identifying patients with familial hypercholesterolemia in the era of genetic testing.

Familial hypercholesterolemia (FH) is a common, inherited disorder of cholesterol metabolism characterized by very high plasma concentrations of low-density lipoprotein cholesterol. It is crucial to diagnose and treat this disorder early since if left untreated it increases the risk for coronary artery disease (CAD) at least by 10-fold. Although genetic testing for FH, when available and affordable, should ideally be offered to most individuals with clinical phenotype suggestive of FH, it is underutilized in most countries. Therefore, FH diagnosis in the majority of cases is made by combining cholesterol levels and clinical characteristics of the patient leaving the need for genetic testing usually in equivocal cases. The presence of some cutaneous and ocular signs can raise the suspicion or even lead to the diagnosis of FH among usually "healthy" individuals. These physical signs comprise cutaneous lesions such as tendon xanthomas or the less specific xanthelasmata and ocular signs, such as corneal arcus in individuals under the age of 45 years. The presence of these signs should prompt the physician to request lipid tests and use clinical scores to diagnose FH. If the diagnosis of FH is likely, aggressive lipid-lowering therapy should be initiated to reduce the risk of CAD and a cascade screening of family members should also be requested.

Effect of intensive LDL cholesterol lowering with PCSK9 monoclonal antibodies on tendon xanthoma regression in familial hypercholesterolemia.

BACKGROUND AND AIMS: The effect of LDLc lowering with PCSK9 antibodies on tendon xanthomas (TX) is unknown. METHODS: TX was measured in 24 heterozygous familial hypercholesterolemia (HeFH) cases and in 24 HeFH controls with or without PCSK9 inhibitors for at least one year. RESULTS: Exposure to PCSK9 inhibitors in cases was 2.96 ± 1.33 years. LDLc decreased 80.8 ± 7.66% in cases and 56.9 ± 11.1% in controls. There was a decrease in maximum (-5.03%) and mean (-5.32%) TX in cases but not in controls (+3.97%, +3.16, respectively, p = 0.01). PCSK9 inhibitor treatment was independently associated with TX reduction. CONCLUSION: Addition of a PCSK9 inhibitor to statin and ezetimibe resulted in a greater decrease in LDLc and TX after 3 years of treatment.

Cerebrotendinous xanthomatosis.

Cerebrotendinous xanthomatosis is a rare autosomal recessive lipid storage disorder affecting the biosynthetic pathway of bile acids, leading to increased cholestanol formation and its accumulation in various tissues. Patients can present with tendon xanthomas, gait abnormalities, osteoporosis with or without a pathological fracture, diminished vision, intractable diarrhoea, seizures, ataxia, psychosis, and mental retardation. We report a 20-year-old man who presented with multiple recurrent tendon swellings and seizures. The earlier diagnosis and treatment helps in preventing the devastating neurological sequalae of this sinister condition. Treatment with chenodeoxycholic acid is crucial in preventing the progression of this rare disorder.