[Evaluation of two automated methods for blood lactate levels]. / Evaluation de deux méthodes de dosage de la concentration sanguine de lactate.

We evaluated two automated methods for measuring blood levels of lactates with Integra 800 (Roche Diagnostics) and ABL 725 (Radiometer). Our evaluation had shown a within run imprecision of 1% (Intégra 800) and 2% (ABL 725) and a between-assay imprecision of 2% (Intégra 800) and 5% (ABL 725). The two methodologies appeared very well associated. The selective electrode remains expensive but it is very interesting because it saves a blood sample.

[Biological signifiance of 410 microcytosis]. / Signification biologique de 410 microcytoses de découverte fortuite chez des adultes jeunes.

We have detected 410 microcytosis among biological tests of military people. These microcytosis are principally coumpounded by haemoglobin's abnormalities (minor thalassemia, sickle cell diseases, E haemoglobin cases and cases of C haemoglobin) and cases of iron deficiency, usually among women.

[Acute organophosphorus pesticide poisoning and cholinesterases activities]. / Intoxication aiguë au pesticide organophosphoré et activités des cholinestérases.

Suicides attempts with an organophosphate pesticide still occur in Brittany, an agricultural French area. The acute poisoning due to this nerve agent, responsible for the inhibition of the cholinesterases enzymes, is severe and can be fatal. The diagnosis is based on the decrease of cholinesterases activity, an assay which has been performed because of the patient context. The measurement of butyrylcholinesterases activity in emergency guarantees an appropriate and rapid management of the patient in order to rapidly regenerate cholinesterases. Even if the decrease level of butyrylcholinesterases activity does not give a significant prognostic value, its follow-up with time indicates the efficacy of the treatment and the gradual remission. In routine the measurement of acetylcholinesterase activity is more useful for the biological follow-up of subjects exposed to organophosphate phytosanitary compounds.

[Evaluation of an automated method for measuring low-density lipoprotein cholesterol]. / Evaluation du dosage direct du cholestérol des lipoprotéines LDL.

We evaluated an automated method for measuring low-density lipoprotein cholesterol (LDL-cholesterol) with Integra 800 (Roche Diagnostics). This method uses detergents which show selectivity for the different lipoproteins. Our evaluation has shown a within run imprecision of 2% and a between-assay imprecision of 1.2%. This method was not perturbed by haemoglobin, bilirubin or lipids. However, the reagents remain expensive: we will use it when calculation or interpretation of lipid results are not possible.

[Histamine food poisoning]. / Les intoxications alimentaires histaminiques.

The authors describe a collective histamine related food-poisoning epidemic that occurred in the Navy due to the consumption of imported smoked swordfish (Xyphias gladius). Twenty cases were detected. The relative risk among consumers of swordfish is at 7.44 (C.I. of 95%: 2.57-21.59) and the doses of histamine were from 2.030 to 4.750 ppm in 9 samples of tested fish (N < 200 ppm). The interest in using a high-resolution chromatographic liquid to ensure a diagnosis, and in using the community norms in force are shown. A recent review of the literature serves to show the variety of fish responsible for this type of accident, to insist on the mildness, elusiveness, variability, and lack of specificity of clinical signs and therefore risks error in diagnoses, treatment and under-reporting of this type of collective food-poisoning.

[Is plasma lipoprotein (a) level a reliable indicator predicting restenosis after angioplasty?]. / Le taux plasmatique de lipoprotéine (a) permet-il de prédire la resténose après angioplastie?

Lipoprotein (a) [Lp(a)] is an independent genetically determined marker of coronary artery disease. It is present in the atheromatous plaque with a molecular structure similar to that of plasminogen. Its role in postangioplasty restenosis is a possibility but is controversial. A population of 103 coronary patients underwent angioplasty with control coronary angiography before the 6th month; there were 53 good results and 50 cases of restenosis. The Lp(a) was measured by immunonephelemetry (threshold value of 250 mg/l). A subgroup with Lp(a) concentrations > 250 mg/l was identified. The average concentrations of Lp(a) in the two groups without restenosis (368 +/- 350 mg/l) and with restenosis (418 +/- 434 mg/l) were not statisticaly different (p = 0.2). When cases with Lp(a) > 250 mg/l were considered alone, the tendency to higher average concentrations of Lp(a) in the group with restenosis (777 +/- 424 mg/l) compared with the group without restenosis (656 +/- 340 mg/l) was more clear-cut but did not achieve statistical significance (p = 0.08). The individual scatter of Lp(a) being very wide (83 to 1,450 mg/l in the group without restenosis and 90 to 1,740 mg/l in the group with restenosis), it is impossible to predict restenosis from this parameter in a given individual. No correlations were observed between the different lipid fractions and restenosis. The extension of the lesions and the angioplasty site did not correlate with restenosis in this study. The authors conclude: 1) that the Lp(a) concentration has no individual predictive value for restenosis; 2) individuals with Lp(a) concentrations > 250 mg/l have an increased risk of restenosis (NS); 3) these results confirm other recent publications; and 4) further research into the isoforms of Lp(a) in each group could provide interesting data.

[Evaluation of coronary risk: a new technique of measuring lipoprotein (a)]. / Evaluation du risque coronaire: une nouvelle technique de dosage de la lipoprotéine (a).

The aim of this study was to assess the reliability of immuno-nephelemetric assay (INA) of lipoprotein (Lp(a)) compared with immuno-radiometric (IRMA) and immuno-enzymologic (ELISA) assays in a coronary (P1) and a non-coronary (P2) populations. The serums of 66 coronary subjects (P1) with an average age of 61.5 +/- 10 years and 137 non-coronary subjects (P2) with an average age of 54 +/- 12 years were analysed by the 3 techniques. The technical characteristics of the INA were: negligeable interference with plasminogen (PLG) (< 1/100) for PLG < 375 mg/l; excellent repeatability and reproducibility at low, medium and high concentrations, respectively 12.3 and 7.5%. 1.2 and 1.2%, 1.3 and 1.1%, low dependance on sample conservation (stable 5 days at +4 degrees C), excellent practicability (simple and quick automised analysis: 10 min). The linear correlations with the concentrations of Lp(a) were: excellent with INA/IRMA P1 and P2: 0.99; very good with INA/ELISA P1: 0.88 and P2: 0.85; very good between IRMA/ELISA P1: 0.91 and P2: 0.87. The average values of Lp(a) were 386 mg/l (INA), 339 mg/l (IRMA), 316 mg/l (ELISA) for P1, and 231 mg/l (INA), 212 mg/l (IRMA) and 153 mg/l (ELISA) for P2, with a significant difference between P1 and P2 with all three techniques: 0.0138 (INA), 0.0207 (IRMA) and 0.0001 (ELISA). The authors concluded that measuring Lp(a) by INA is reliable with respect to IRMA and ELISA techniques, as accurate, quicker, automatised and cheaper, compensating for a lower sensitivity, a calculated risk of a non-specific reaction and the necessity of a shorter delay of analysis. The comparative results in two populations demonstrate it to be an excellent marker of coronary risk for epidemiological studies, independant of other risk factors.

[Aluminum, hypothetic cause of Alzheimer disease]. / L'aluminium, cause hypothétique de la maladie d'Alzheimer.

A great deal of research has focused on aluminium as a putative causative factor in Alzheimer's disease. We measured by atomic absorption spectrophotometry aluminium levels in blood, urine and cerebrospinal fluid from 15 patients with Alzheimer's disease, compared with 20 control individuals. There were no statistically significant differences between the two groups. This suggests that aluminium is not a causative factor for Alzheimer's disease.