Monitoring of glycemic balance by glycated hemoglobin assay on D-10® (Biorad) and Minicap Flex Piercing® (Sebia) biochemical systems at the Rodolph-Mérieux Laboratory in Bamako / Suivi de l'équilibre glycémique par le dosage de l'hémoglobine glyquée sur les automates de biochimie D-10® (Biorad) et Minicap Flex Piercing® (Sebia) au Laboratoire RodolpheMérieux de Bamako

This study aims to determine the concordance of results between D-10® and Minicap Flex Piercing® and the impact of the presence of hemoglobin variants in the glycated hemoglobin assay. All the samples were assayed in parallel. The agreement between these methods was assessed using the Bland and Altman plot. We collected a total of 166 samples. In the entire study population and in patients with a hemoglobin variant, the Bland and Altman graph showed good agreement between the values (for respective biases of 0.21% and 0.29%) as well as a significant correlation (p < 0.001). Our results differ from those found by Kesso Barry et al. This difference can be explained by the high prevalence of patients with abnormal hemoglobins S and C (39.2 %) in our study population. Despite a good agreement between the methods, the results do not allow us to confirm a transferability between the two systems in diabetics and carriers of hemoglobin variants.

Notre étude vise à déterminer la concordance des résultats entre le D-10® et le Minicap Flex Piercing®, ainsi que l'impact de la présence des variants d'hémoglobine dans le dosage de l'hémoglobine glyquée. Tous les échantillons ont été dosés en parallèle sur les deux automates. L'évaluation de la concordance a été réalisée grâce au diagramme de Bland et Altman. Nous avons colligé un total de 166 échantillons. Chez l'ensemble de la population d'étude et chez les patients avec un variant d'hémoglobine, le graphique de Bland et Altman a montré une bonne concordance entre les valeurs (pour des biais respectifs de 0,21 % et 0,29 %) ainsi qu'une corrélation significative (p < 0,001). Nos résultats diffèrent de ceux trouvés par Kesso Barry et al. Cette différence peut s'expliquer par la forte prévalence de patients possédant des hémoglobines anormales S et C (39,2 %) dans notre population d'étude. Malgré une bonne concordance, nos résultats ne permettent pas d'affirmer une transférabilité entre les deux systèmes chez les diabétiques et les porteurs de variants d'hémoglobine.

Sexual Dimorphism of Metabolomic Profile in Arterial Hypertension.

Metabolomic studies have demonstrated the existence of biological signatures in blood of patients with arterial hypertension, but no study has hitherto reported the sexual dimorphism of these signatures. We compared the plasma metabolomic profiles of 28 individuals (13 women and 15 men) with essential arterial hypertension with those of a healthy control group (18 women and 18 men), using targeted metabolomics. Among the 188 metabolites explored, 152 were accurately measured. Supervised OPLS-DA (orthogonal partial least squares-discriminant analysis) showed good predictive performance for hypertension in both sexes (Q2cum = 0.59 in women and 0.60 in men) with low risk of overfitting (p-value-CV ANOVA = 0.004 in women and men). Seventy-five and 65 discriminant metabolites with a VIP (variable importance for the projection) greater than 1 were evidenced in women and men, respectively. Both sexes showed a considerable increase in phosphatidylcholines, a decrease in C16:0 with an increase in C28:1 lysophosphatidylcholines, an increase in sphingomyelins, as well as an increase of symmetric dimethylarginine (SDMA), acetyl-ornithine and hydroxyproline. Twenty-nine metabolites, involved in phospholipidic and cardiac remodeling, arginine/nitric oxide pathway and antihypertensive and insulin resistance mechanisms, discriminated the metabolic sexual dimorphism of hypertension. Our results highlight the importance of sexual dimorphism in arterial hypertension.

Sickle Cell Disease: Metabolomic Profiles of Vaso-Occlusive Crisis in Plasma and Erythrocytes.

The metabolomic profile of vaso-occlusive crisis, compared to the basal state of sickle cell disease, has never been reported to our knowledge. Using a standardized targeted metabolomic approach, performed on plasma and erythrocyte fractions, we compared these two states of the disease in the same group of 40 patients. Among the 188 metabolites analyzed, 153 were accurately measured in plasma and 143 in red blood cells. Supervised paired partial least squares discriminant analysis (pPLS-DA) showed good predictive performance for test sets with median area under the receiver operating characteristic (AUROC) curves of 99% and mean p-values of 0.0005 and 0.0002 in plasma and erythrocytes, respectively. A total of 63 metabolites allowed discrimination between the two groups in the plasma, whereas 61 allowed discrimination in the erythrocytes. Overall, this signature points to altered arginine and nitric oxide metabolism, pain pathophysiology, hypoxia and energetic crisis, and membrane remodeling of red blood cells. It also revealed the alteration of metabolite concentrations that had not been previously associated with sickle cell disease. Our results demonstrate that the vaso-occlusive crisis has a specific metabolomic signature, distinct from that observed at steady state, which may be potentially helpful for finding predictive biomarkers for this acute life-threatening episode.

[Multiparametric biochemical analysis revealing an increase of homocysteinemia and NT-proBNP in hypertensive patients living in Bamako (Mali)]. / Analyse biochimique multi-paramétrique révélant une augmentation de l'homocystéinémie et du NT-ProBNP chez les patients hypertendus à Bamako (Mali).

INTRODUCTION: Arterial hypertension is a major public health problem in sub-Saharan Africa due to its high frequency and to the cardiovascular risk that it entails. The purpose of this study was to assess the prevalence of clinical and biological risk factors of hypertension in Bamako (Mali). METHODS: We conducted a case-control study, stratified in function of the sex, of 72 participants including 36 patients with hypertension and 36 controls. Twenty-two plasma biochemical parameters have been measured and analyzed using univariate and multivariate tests. RESULTS: Hyperhomocysteinemia was found in 55.6% of women (p = 0.03) and 100% of men (p = 0.007) with hypertension. High NT-proBNP was also found in 16.7% of women (VIP > 1 in multivariate model) and of men with hypertension (p = 0.00006). A good multivariate predictive model (OPLS-DA) was only obtained in women with high blood pressure, with Q2cum = 0.73, attesting severe sexual dimorphism associated with arterial hypertension. This model involved eight parameters whose plasma concentration was modified (homocysteine, NT-proBNP, potassium, urea, blood glucose, sodium, chlorine and total proteins). CONCLUSION: We registered a significant association between hyperhomocysteinemia and arterial hypertension. Therefore, the assay of homocysteine associated with good management would decrease the risk of cardiovascular diseases while improving the quality of life of hypertensive patients.

Analyse biochimique multi-paramétrique révélant une augmentation de l'homocystéinémie et de la NT-ProBNP chez les patients hypertendus à Bamako (Mali)

Introduction: l'hypertension artérielle est un problème majeur de santé publique en Afrique subsaharienne par sa fréquence élevée et le risque cardiovasculaire qu'elle entraine. L'objectif de cette étude était d'évaluer la prévalence des facteurs de risques cliniques et biologiques de l'hypertension artérielle à Bamako (Mali).Méthodes: il s'agit d'une étude cas-témoin, stratifiée en fonction du sexe, portant sur 72 participants dont 36 hypertendus et 36 contrôles. Vingt-deux paramètres biochimiques plasmatiques ont été mesurés et analysés par des tests univariés et multivariés.Résultats: une hyperhomocystéinémie a été retrouvée chez 55,6% des femmes (p = 0,03) et 100% des hommes (p = 0,007) hypertendus. Le N-terminal pro B-type natriuretic peptide (NT-ProBNP) était également augmenté chez 16,7% des femmes (VIP > 1 dans le modèle multivarié) et des hommes hypertendus (p = 0,00006). Un bon modèle multivarié prédictif (OPLS-DA) a uniquement été obtenu chez les femmes hypertendues, avec un Q2cum = 0,73, attestant ainsi d'un important dimorphisme sexuel associé à l'hypertension artérielle. Ce modèle impliquait huit paramètres dont la concentration plasmatique était modifiée (homocystéine, NT-ProBNP, potassium, urée, glycémie, sodium, chlore et protéines totales).Conclusion: nous avons noté une association significative entre l'hyperhomocystéinémie et l'hypertension artérielle. Par conséquent, le dosage de l'homocystéine associé à une bonne prise en charge diminuerait le risque cardiovasculaire tout en améliorant la qualité de vie des patients hypertendus

Yersinia enterocolitica, a Neglected Cause of Human Enteric Infections in Côte d'Ivoire.

BACKGROUND: Enteropathogenic Yersinia circulate in the pig reservoir and are the third bacterial cause of human gastrointestinal infections in Europe. In West Africa, reports of human yersiniosis are rare. This study was conducted to determine whether pathogenic Yersinia are circulating in pig farms and are responsible for human infections in the Abidjan District. METHODOLOGY/PRINCIPAL FINDINGS: From June 2012 to December 2013, pig feces were collected monthly in 41 swine farms of the Abidjan district. Of the 781 samples collected, 19 Yersinia strains were isolated in 3 farms: 7 non-pathogenic Yersinia intermedia and 12 pathogenic Yersinia enterocolitica bioserotype 4/O:3. Farm animals other than pigs and wild animals were not found infected. Furthermore, 2 Y. enterocolitica 4/O:3 strains were isolated from 426 fecal samples of patients with digestive disorders. All 14 Y. enterocolitica strains shared the same PFGE and MLVA profile, indicating their close genetic relationship. However, while 6 of them displayed the usual phage type VIII, the other 8 had the highly infrequent phage type XI. Whole genome sequencing and SNP analysis of individual colonies revealed that phage type XI strains had unusually high rates of mutations. These strains displayed a hypermutator phenotype that was attributable to a large deletion in the mutS gene involved in DNA mismatch repair. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that pathogenic Y. enterocolitica circulate in the pig reservoir in Côte d'Ivoire and cause human infections with a prevalence comparable to that of many developed countries. The paucity of reports of yersiniosis in West Africa is most likely attributable to a lack of active detection rather than to an absence of the microorganism. The identification of hypermutator strains in pigs and humans is of concern as these strains can rapidly acquire selective advantages that may increase their fitness, pathogenicity or resistance to commonly used treatments.