Chylopericardium or contamination by injectable lipid emulsion? / « Mets la main sur mon cœur, Et vois comme il se trouble ¼ ­ un pseudo-chylopéricarde ?

Effusions can show some surprises. We document the case of a fourteen-month-old male patient with short-bowel syndrome, hospitalized in a cardiology unit, receiving a chronic parenteral nutrition by a Broviac® catheter. The patient presented several thrombosis following iterative catheter replacements. In parallel with superior vena cava plasty, a right intra-atrial Broviac® catheter was placed in the absence of other peripheral venous accesses. This device has a cutaneous exit site to allow for infusion of a hyperosmolar lipid emulsion. Seven days later, a milky liquid was secreted from pericardial/mediastinal redon. A gel lipoprotein electrophoresis of the fluid suggested a preliminary diagnosis of chylopericardium. However, biochemical testing of certain analytes evoked a parenteral nutrition-related pericardial effusion and a possible pseudochyloperitoneum caused by the shearing of a migrated Broviac® in pericardium. The patient, on a fat-free diet, was admitted to the ICU to drain the effusion and reposition the catheter, with success. In the light of new datas on the interference of parenteral lipid emulsions with the lipoproteins gel electrophoresis, we will try to determine whether the apparent presence of chylomicrons in the gel would be the sign of a lesion of the lymphatic system, or rather the result of a contamination by artificial chylomicron in the lipid emulsion, if not the sign of contaminated blood. In our article, we highlight several considerations in identifying and confirming cases of pericardial effusion, such as chylopericardium and parenteral nutrition-related one, as well as points concerning the use of lipid emulsions for pediatric patients with short-bowel syndrome.

Les liquides d'épanchements peuvent renfermer quelques surprises. Nous documentons le cas d'un patient de quatorze mois, hospitalisé en cardiologie, présentant un syndrome de grêle court et recevant une nutrition parentérale au long cours par cathéter Broviac®. Le patient présentait de multiples occlusions veineuses consécutives aux changements itératifs du dispositif. En parallèle d'une plastie de la veine cave supérieure, un Broviac® a été posé en intra-atrial droit devant l'absence d'autres abords veineux périphériques. Ce dispositif comporte un orifice de sortie sous-cutané pour apporter une solution de nutrition hyperosmolaire de type émulsion lipidique. Le liquide recueilli dans les drains péricardiques en post-opératoire est lactescent, particulièrement à partir du septième jour. Le lipidogramme du liquide d'épanchement péricardique semble conclure à la présence de chylomicrons - un chylopéricarde. Cependant, le dosage de certains analytes penche en faveur d'un perfusopéricarde, probablement pseudochyleux, lié au cisaillement du Broviac® dont l'extrémité a migré de l'oreillette droite au péricarde. Le patient, sous régime sans graisses, sans nutrition parentérale, sera réopéré pour drainer l'épanchement et repositionner le cathéter, avec succès. À la lumière de données originales quant à l'interférence des émulsions lipidiques sur le lipidogramme, nous tâcherons de déterminer si l'apparente présence de chylomicrons sur le gel serait le témoin d'une réelle lésion du lymphatique, ou plutôt le fruit d'une contamination par l'émulsion, si ce n'est par le sang. Des considérations au sujet des épanchements péricardiques, dont les chylopéricarde et nutripéricarde, ainsi que sur les émulsions lipidiques pédiatriques dans le contexte du grêle court émailleront ce travail.

[Electrophoresis of serum lipoproteins (lipoproteinogram) with the Hydragel Lipo + Lp(a)® (Sebia) kit: evaluation of Fat Red 7B staining]. / Électrophorèse des lipoprotéines sériques (lipoprotéinogramme) par le kit Hydragel Lipo + Lp(a)® (Sebia) : évaluation de la coloration au Fat Red 7B.

The lipoproteinogram (or lipidogram) consists in an electrophoretic separation of the main classes of serum lipoproteins. Separation was done in agarose gel using the Sebia Hydragel Lipo + Lp(a)® kit. A repeatability study (n=6) was conducted on 3 sera (1 normolipidemic, 1 hypertriglyceridemic and 1 with a high Lp(a) concentration). The reproducibility was studied on these 3 sera and on an ascites liquid containing chylomicrons, upon 6 days (n=6). A quantitative approach was made by studying areas under the curve and percentages of fractions. In both cases (repeatability and reproducibility), the revelation of the lipoproteins in the gel after electrophoretic migration was made either by staining with Sudan Black (procedure recommended by Sebia), or with Fat Red 7B. Regardless of staining, both repeatability and reproducibility studies show that all lipoprotein fractions were correctly detected at their respective positions, leading to satisfactory interpretations of lipoproteinograms. Our reproducibility study also confirmed a good stability of the fractions over 6 days (storage at +5 ± 3̊C). In addition, the Fat Red 7B staining leads to a shorter technical time (about 40 min) for the gel drying and staining/destaining phases, which allows us to respond more quickly to certain urgent requests such as chylothorax diagnosis.

Evaluation of a semi-automatic isoelectric focusing method for apolipoprotein E phenotyping.

A qualitative, semi-automatized method for apolipoprotein E (apoE) phenotyping by isoelectric focusing method has been evaluated on 40 serum samples from patients previously genotyped for apoE, especially as regards concordance with genotyping, but also repeatability and reproducibility of the method, and sample storage. Total concordance with genotyping and good precision criteria, together with its practicability and requirement of a little sample volume, lead to conclude to the usefulness of this method to help clinicians in the diagnosis of dyslipidemic and neurodegenerative diseases.

Endogenous CETP activity as a predictor of cardiovascular risk: determination of the optimal range.

OBJECTIVES: To identify key determinants of plasma endogenous CETP activity and threshold value of plasma CETP activity associated with high cardiovascular risk. METHODS: Endogenous plasma CETP activity was measured in a total of 1403 individuals. RESULTS: Multivariate analysis revealed that 23.5% of endogenous CETP activity variability was explained by plasma LDL-C (12.0%), HDL-C (6.4%) and TG (4.4%) whereas sex and BMI accounted together for only 0.7% of its variability. Scoring patients for cardiovascular risk on the basis of their plasma lipid levels (TC, TG, LDL-C and HDL-C), revealed that patients with high cardiovascular risk (score ≥3) displayed a mean endogenous plasma CETP activity above 34%. CONCLUSION: Plasma CETP activity represents a potent indicator of cardiovascular risk in patients with metabolic disorders since it integrates major independent risk factors.

Determinants of low-density lipoprotein particle diameter during antiretroviral therapy including protease inhibitors in HIV-1-infected patients.

BACKGROUND: Lipid disorders are frequent in HIV-1-infected patients taking combination antiretroviral therapy (cART) that includes protease inhibitors (PIs). The presence of small dense low-density lipoprotein particles might be an important predictive marker of cardiovascular disease in this setting. This cross-sectional substudy of the ANRS 126 trial was designed to identify variables influencing LDL diameter. METHODS: We studied 81 stable HIV-1-infected patients with dyslipidaemia (LDL-cholesterol >4.1 mmol/l, triglycerides <8.8 mmol/l) receiving PI-including cART regimens and no lipid-lowering drugs. LDL diameter was assessed by gradient gel electrophoresis. Relationships between LDL diameter and demographic, metabolic and HIV-related variables were identified by using non-parametric univariate tests and multiple linear regression models. RESULTS: In univariate analysis, LDL diameter was related to demographic variables, triglyceride (TG) levels, high-density lipoprotein cholesterol (HDL-c) levels, and the numbers and duration of exposure to nucleoside reverse transcriptase inhibitors and PIs. In multivariable linear regression analysis, LDL diameter was negatively associated with the TG level (P<0.0001) and positively associated with the HDL-c level (P<0.0001). For each 1-mmol/l increase in TG, LDL diameter fell by 0.281 nm. Conversely, for each 1-mmol/l increase in HDL-c, LDL diameter rose by 1.175 nm. CONCLUSIONS: Higher TG and lower HDL-c levels are associated with smaller LDL particle diameter. Small-diameter LDL particles could contribute to early atherogenic processes in HIV-1-infected patients on cART.