Réponse à la vaccination contre le SARS-CoV-2 chez des patients hémodialysés chroniques

Introduction

Les patients hémodialysés chroniques (HDC) sont à haut risque de développer une forme grave d’infection à SARS-CoV-2. Ils constituent une population cible pour la vaccination. Toutefois, la réponse vaccinale chez ces patients n’est pas connue.

Matériels et méthodes

Étude observationnelle monocentrique portant sur l’ensemble des patients HDC à qui la vaccination contre la COVID-19 par le vaccin à ARNm BNT162b2 (Pfizer–BioNTech®) a été proposée. Deux injections ont été réalisées à 28 j d’intervalle, dans le bras opposé à l’abord vasculaire. Les données cliniques ont été recueillies prospectivement. La recherche d’anticorps spécifiques (IgG et IgM anti-protéine Spike) a été réalisée par immunochromatographie (COVID-19 BSS, Biosynex®) sur des sérums collectés avant la première injection, puis avant la seconde et 1 mois après. Les résultats sont exprimés en médiane [IQR : 25–75] ou %.

Résultats

Entre le 15 janvier et le 21 mars 2021, la vaccination a été proposée aux 55 patients du centre et acceptée par 49 (89,1 %) patients, les 6 autres ayant refusé. Parmi les 49 patients vaccinés, l’âge médian est de 70 [63–82,5] ans, 17 (34,7 %) sont diabétiques, et 8 (16,3 %) ont une greffe d’organe solide. La durée médiane en dialyse à la vaccination est de 26,2 [17,8–49,9] mois ; les patients sont dialysés sur une membrane en polysulfone (PSF), sauf 4 (8,2 %) sur une membrane en polyméthylmétacrylate (PMMA).

La séroprévalence en IgG à j0 est de 12,2 % (6/49 patients, dont 4 ayant un antécédent de COVID symptomatique de plus de 3 mois, avec PCR positive). Parmi les 43 patients séronégatifs à l’inclusion, 10 sont encore en cours de vaccination. Les 33 patients ayant complété le schéma vaccinal ont les résultats suivants, respectivement avant la seconde injection et 1 mois après : IgM, 9,1 % (3 patients) et 12,1 % (4 patients) ; IgG, 9,1 % (3 patients) et 87,9 % (29 patients).

Tous les patients positifs en IgM le sont également en IgG (aucun n’a développé de signes cliniques évocateurs de COVID-19 dans le suivi). Parmi les 4 patients non répondeurs, 1 recevait une immunothérapie pour cancer cutané, et tous ont une membrane en PSF. Tous les patients transplantés d’organe ont eu une réponse vaccinale positive 1 mois après la seconde injection. Le profil sérologique des patients dialysés avec un filtre en PMMA est comparable à ceux avec un filtre en PSF. La tolérance est bonne: 1 patiente a présenté une réponse systémique avec fièvre et frisson, et 60,1 % ont eu une réaction douloureuse au point d’injection ayant duré 24 h.

Conclusion

L’acceptation et la réponse vaccinale au vaccin à ARNm contre la COVID-19 sont bonnes chez les patients HDC.

Do children and adolescents with type 1 diabetes suffer from a lack of resources in France? Results from a benchmark study in the New Aquitaine region

BACKGROUND

A benchmark study was conducted in the southwest of France, in the New Aquitaine region, to investigate metabolic outcomes and availability of resources in pediatric diabetes units. We assessed whether the level of care was in accordance with the International Society for Pediatric and Adolescent Diabetes recommendations.

METHODS

Demographic and clinical data were collected, as were all HbA1c tests for the 2017 calendar year. Pediatricians specialized in diabetes care were invited to complete an online survey concerning means allocated to the management of type 1 diabetes in their centers.

RESULTS

Sixteen centers provided data for 1277 patients and 3873 clinical visits. A total of 1115 children suffering from diabetes for more than 1 year were studied. Median HbA1c was 8% (7.4-8.6) for the whole region. Only 29.2% of children had good metabolic control in accordance with the <7.5% target. We identified slight but significant variation in glycemic control among centers (P=0.029). The use of an insulin pump varied greatly among centers but did not explain HbA1c differences. We did not identify a correlation between medical or paramedical time dedicated to the follow-up of diabetic patients and the mean HbA1c of each center. For 100 diabetic patients, follow-up was provided by 0.42 physicians (0.23-1.50), 0.15 nurses (0-0.56), 0.12 dietitians (0-0.48), and 0.07 psychologists (0-0.30).

CONCLUSION

This study demonstrates a lack of human resources allocated to the management of type 1 diabetes in the region that is far below international recommendations. The proportion of children achieving the international glycemic target is low. There is a clear need to improve glycemic control in children, which will only be possible with improved professional practices, encouraged by benchmark studies, and by increasing the size of our multidisciplinary teams.

P1802Management and outcomes of infective endocarditis in adults with congenital heart disease

Background

Causes, epidemiology and microbiology of infective endocarditis (IE) have evolved in recent decades. Although novel tools for the diagnosis and therapeutic strategies have emerged, mortality and morbidity remain high. These trends may particularly concern the growing population of adults with congenital heart disease (CHD) who are at increased risk for IE.

Purpose

We aimed to characterize IE in CHD patients and describe management and outcome in this setting. We also sought to determine the risk factors associated with in-hospital death in CHD patients.

Methods

From January 2000 to June 2018, 666 consecutive episodes of IE in adults were recorded in our center. Among them, 143 concerned CHD, including 5 implantable cardiac electronic devices-lead infections, all managed by an IE team including CHD specialists. Cases were classified according to modified Duke criteria.

Results

CHD patients were significantly younger (37 years IQR [26–52]), with a more common history of cardiac reoperations (numbers of sternotomies≥2 in 35.7%) and infective endocarditis (19.7%, p<0.01) compared to non-CHD patients. There were more infections of valve-containing prosthetics (44% vs. 30%, p<0.04), and the right heart side (41.5%, p<0.01) in CHD patients. Forty-nine percent of them had a simple CHD, 12.7% a moderate, and 36.4% a complex. A predisposing event could be identified in only 34% of cases. Oral streptococci/Streptococci bovis and Staphylococcus aureus were the most frequently microorganisms isolated (32.4% and 20.4%, respectively). Surgery was performed in 90 episodes (62%), and was selected in emergency (<24h) in 61% (figure 1). In-hospital mortality was 12.7% and was directly related to IE in 10/18 cases. CHD patients had a significant lower risk of death compared to non-CHD patients (OR=0.47, p=0.026, p<0.01), even after adjustment for age, and the infected heart side. On multivariate analysis the complexity of CHD (if simple CHD: OR=0.07 IQR [0.01 to 0.44], p<0.01) and the white blood cell count (OR=1.18 IQR [1.04 to 1.33], p=0.01) were the strongest predictive factors of in-hospital death in the CHD group.

Conclusions

Mortality associated with IE in CHD patients is lower than in acquired heart disease. The multidisciplinary approach by IE team and CHD specialists may have improved management and outcome in this setting. However, risk for death remains high in complex lesions. Larger prospective studies on IE in adults with CHD are needed to develop guidelines in these complex patients.

Chronic endocarditis due to Legionella anisa: a first case difficult to diagnose

Endocarditis due to Legionella spp. is uncommon but presumably underestimated given the prevalence of Legionellae in the environment. We report a first and unusual case of chronic native valve endocarditis due to L. anisa and advocate that the diagnosis of endocarditis be made collaboratively between the cardiologist, surgeon, microbiologist and pathologist.

Partition locus-based classification of selected plasmids in Klebsiella pneumoniae, Escherichia coli and Salmonella enterica spp.: an additional tool

The dissemination of antimicrobial resistance genes in Enterobacteriaceae has been largely attributed to plasmids, circular DNA molecules capable of autonomous replication. Whereas high-copy-number plasmids primarily rely on passive diffusion for plasmid maintenance, low-copy-number plasmids utilize so-called partition (par) systems. Plasmid partition relies on three structures, i.e. a centromere like DNA site, a centromere-binding protein and an ATPase or a GTPase motor protein for plasmid positioning. Identification and classification of plasmids is essential for tracing plasmids conferring drug resistance. PCR-based replicon typing is currently the standard method for plasmid identification but there are new classification schemes, especially the relaxase gene typing (PRaseT). Here we developed a multiplex PCR set targeting par loci found on the plasmids most frequently encountered in Enterobacteriaceae. This method, called "plasmid partition gene typing" (PAR-T), was validated with 136 transconjugants or transformants harboring various replicon types. The method was tested with 30 multidrug-resistant clinical isolates including Escherichia coli, Klebsiella pneumoniae and Salmonella enterica subsp. enterica carrying 1-4 replicons; all replicons were tested in parallel with PRaseT for comparison. Six multiplex PCRs and one simplex PCR including 18 pairs of primers recognized plasmids of groups IncA/C, FIA, FIB, FIC, FIIk, FII, HI1, HI2, I1, L/M, N, X. Our set of multiplex PCRs showed high specificity for the classification of resistance plasmids except for IncX replicons.