Analyses of familial chylomicronemia syndrome in Pereira, Colombia 2010-2020: a cross-sectional study

New approaches to triglyceride reduction: Is there any hope left?

Triglycerides play a crucial role in the efficient storage of energy in the body. Mild and moderate hypertriglyceridemia (HTG) is a heterogeneous disorder with significant association with atherosclerotic cardiovascular disease (ASCVD), including myocardial infarction, ischemic stroke, and peripheral artery disease and represents an important component of the residual ASCVD risk in statin treated patients despite optimal low-density lipoprotein cholesterol reduction. Individuals with severe HTG (>1,000 mg/dL) rarely develop atherosclerosis but have an incremental incidence of acute pancreatitis with significant morbidity and mortality. HTG can occur from a combination of genetic (both mono and polygenic) and environmental factors including poor diet, low physical activity, obesity, medications, and diseases like insulin resistance and other endocrine pathologies. HTG represents a potential target for ASCVD risk and pancreatitis risk reduction, however data on ASCVD reduction by treating HTG is still lacking and HTG-associated acute pancreatitis occurs too rarely to effectively demonstrate treatment benefit. In this review, we address the key aspects of HTG pathophysiology and examine the mechanisms and background of current and emerging therapies in the management of HTG.

Validation of the familial chylomicronaemia syndrome (FCS) score in an ethnically diverse cohort from UK FCS registry: Implications for diagnosis and differentiation from multifactorial chylomicronaemia syndrome (MCS)

BACKGROUND AND AIMS

Prognosis and management differ between familial chylomicronaemia syndrome (FCS), a rare autosomal recessive disorder, and multifactorial chylomicronaemia syndrome (MCS) or severe mixed hyperlipidaemia. A clinical scoring tool to differentiate these conditions has been devised but not been validated in other populations. The objective of this study was to validate this score in the UK population and identify any additional factors that might improve it.

METHODS

A retrospective validation study was conducted using data from 151 patients comprising 75 FCS and 76 MCS patients. All participants had undergone genetic testing for genes implicated in FCS. Validation was performed by standard methods. Additional variables were identified from clinical data by logistic regression analysis.

RESULTS

At the recommended FCS score threshold ≥10 points, the sensitivity and specificity of the score in the UK population were 96% and 75%, respectively. The receiver operating characteristic (ROC) curve analysis yielded an area under the curve (AUC) of 0.88 (95% CI 0.83-0.94, p < 0.001). This study identified non-European (predominantly South Asian) ethnicity, parental consanguinity, body mass index (BMI) < 25 kg/m2, and recurrent pancreatitis as additional positive predictors, while BMI >30 kg/m2 was found to be a negative predictor for FCS. However, inclusion of additional FCS predictors had no significant impact on performance of standard FCS score.

CONCLUSIONS

Our study validates the FCS score in the UK population to distinguish FCS from MCS. While additional FCS predictors were identified, they did not improve further the score diagnostic performance.

[A case of neonatal-onset type I hyperlipoproteinemia with bloody ascites]

This report presents a case of a male infant, aged 32 days, who was admitted to the hospital due to 2 days of bloody stools and 1 day of fever. Upon admission, venous blood samples were collected, which appeared pink. Blood biochemistry tests revealed elevated levels of triglycerides and total cholesterol. The familial whole genome sequencing revealed a compound heterozygous variation in the LPL gene, with one variation inherited from the father and the other from the mother. The patient was diagnosed with lipoprotein lipase deficiency-related hyperlipoproteinemia. Acute symptoms including bloody stools, fever, and bloody ascites led to the consideration of acute pancreatitis, and the treatment involved fasting, plasma exchange, and whole blood exchange. Following the definitive diagnosis based on the genetic results, the patient was given a low-fat diet and received treatment with fat-soluble vitamins and trace elements, as well as adjustments to the feeding plan. After a 4-week hospitalization, the patient's condition improved and he was discharged. Follow-up showed a decrease in triglycerides and total cholesterol levels. At the age of 1 year, the patient's growth and psychomotor development were normal. This article emphasizes the multidisciplinary diagnosis and treatment of familial hyperlipoproteinemia presenting with symptoms suggestive of acute pancreatitis, including bloody ascites, in the neonatal period.

Role of glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 in hypertriglyceridemia and diabetes

In diabetes, the impairment of insulin secretion and insulin resistance contribute to hypertriglyceridemia, as the enzymatic activity of lipoprotein lipase (LPL) depends on insulin action. The transport of LPL to endothelial cells and its enzymatic activity are maintained by the formation of lipolytic complex depending on the multiple positive (glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 [GPIHBP1], apolipoprotein C-II [APOC2], APOA5, heparan sulfate proteoglycan [HSPG], lipase maturation factor 1 [LFM1] and sel-1 suppressor of lin-12-like [SEL1L]) and negative regulators (APOC1, APOC3, angiopoietin-like proteins [ANGPTL]3, ANGPTL4 and ANGPTL8). Among the regulators, GPIHBP1 is a crucial molecule for the translocation of LPL from parenchymal cells to the luminal surface of capillary endothelial cells, and maintenance of lipolytic activity; that is, hydrolyzation of triglyceride into free fatty acids and monoglyceride, and conversion from chylomicron to chylomicron remnant in the exogenous pathway and from very low-density lipoprotein to low-density lipoprotein in the endogenous pathway. The null mutation of GPIHBP1 causes severe hypertriglyceridemia and pancreatitis, and GPIGBP1 autoantibody syndrome also causes severe hypertriglyceridemia and recurrent episodes of acute pancreatitis. In patients with type 2 diabetes, the elevated serum triglyceride levels negatively correlate with circulating LPL levels, and positively with circulating APOC1, APOC3, ANGPTL3, ANGPTL4 and ANGPTL8 levels. In contrast, circulating GPIHBP1 levels are not altered in type 2 diabetes patients with higher serum triglyceride levels, whereas they are elevated in type 2 diabetes patients with diabetic retinopathy and nephropathy. The circulating regulators of lipolytic complex might be new biomarkers for lipid and glucose metabolism, and diabetic vascular complications.