Projet PRODIADOM "Promouvoir la dialyse à domicile"

PRODIADOM est une solution innovante destinée à aider les professionnels qui souhaitent développer la dialyse à domicile. Dans un premier temps disponible pour la dialyse péritonéale (bientôt disponible pour l’hémodialyse à domicile), PRODIADOM propose un site Web qui se veut simple, pratique, utile et convivial. Les praticiens pourront y trouver des formations, des guides, des fiches pratiques, des arborescences décisionnelles, des conduites à tenir face à des situations inhabituelles, des recommandations, tous les protocoles utiles pour la dialyse péritonéale, toutes les explorations fonctionnelles péritonéales courantes, avec leurs indications et leur réalisation pratique. PRODIADOM a l’ambition de devenir la référence des professionnels médicaux et paramédicaux qui souhaitent démarrer un programme de dialyse à domicile. Conçu par des experts, son accès est gratuit.

Home dialysis and Covid-19 in french speaking countries (RDPLF data-base)

Aims of the study: to assess the frequency of symptomatic Covid-19 in home dialysis patients and its influence on the number of patients treated at home in dialysis units of centers included in the French-speaking peritoneal and home hemodialysis Registry (RDPLF). Focus is placed on patients treated by peritoneal dialysis (PD) in mainland France. Results: in home hemodialysis (HHD)the incidence is 6% in Belgium and 4.8% in mainland France. On peritoneal dialysis it is 10.6% in Belgium, 6.7% in mainland France, 10.8% in Morocco and 11.5% in Tunisia. Lethality is less than 5% in HHD and between 8.4% and 42.7% in PD depending on age and associated comorbidities. In France, the percentage of patients who have had symptomatic Covid-19 is lower on home dialysis, all methods combined. Nevertheless, among the home methods, the higher frequencies and severities are observed in mainland France in home assisted PD: these are the oldest and most co-morbid patients. Transfers from PD to in center hemodialysis have increased during Covid-19 pandemic while the number of transplants has decreased. Conclusion: if the drop in the number of transplants can be explained by a reduced availability of operating theaters and surgical teams during a pandemic period, it is paradoxical that the prescription of home dialysis, which should be supposed to limit the risk of contagion, has decreased. More investigation should be performed to understand this paradox.  

Can blood pressure be measured without undressing patients ?

The guidelines recommend that the technique of measuring arterial blood pressure requires positioning the cuff on a bare arm, without rolled-up sleeve. These recommendations are sometimes difficult to apply in routine practice, as in dialysis centers where the measurement is repeated in fragile patients. In this study, we assess the validity of the blood pressure measurement with a cuff positioned on a bare arm, compared to a cuff positioned on several layers of clothing. A total of 1,224 blood pressure measurements were taken in 51 dialysis patients over a period of one month, 6 measurements per week, i.e. 24 measurements per patient. The patients wore their ordinary clothes suitable for a winter season. Thus, 612 measurements were taken with a cuff on a bare arm, and 612 measurements with a cuff on clothing. The mean systolic pressures were 121.9 and 123.5 mmHg, respectively when the cuff was placed on clothing and bare skin. The mean diastolic pressure was 60.1 and 60.5 mmHg, respectively. The observed difference does not reach the level of statistical significance with respectively p = 0.168 and p = 0.135. The same is true for mean arterial pressure, with 80.6 and 81.5 mmHg respectively (p = 0.142). The difference observed does not justify the undressing of patients for whom this procedure is difficult, uncomfortable or painful.

Lowering dialysis sessions duration may be dangerous

Dialysis session in less duration - either to give a better quality of life for the patient or to optimize the organization the dialysis institution - may have bad repercussions on the quality of the treatment and therefore the quality of life of the patient. According to the result of the publications listed in this work, we conclude that it is necessary to perform either longer sessions or more frequent treatments to limit the interval time between two sessions. As this is difficult to perform by the providers, we recommend to develop home dialysis to obtain the best result.

Évaluation de l’intérêt d’une revue de langue française spécialisée en dialyse à domicile

Le Bulletin de la dialyse à domicile est une revue en accès libre à parution trimestrielle, créée en juin 2018. Elle adhère aux normes internationales d'éthique et bonnes pratiques de l'édition médicale ; elle est indexée dans la plupart des bibliothèques universitaires, indexée dans l'index international des revues en libre accès "doaj.org". Le but de ce travail était, au moyen d'un sondage anonyme en ligne, d'évaluer son appréciation auprès des néphrologues et équipes soignantes francophones. L'analyse des réponses a mis en évidence un haut degré d'appréciation par les lecteurs, l'importance d'utiliser la langue maternelle pour abroger les barrières linguistiques d'accès à l'information médicale ou infirmière, le besoin d'articles pratiques mais aussi de recommandations, le partage de cas cliniques. Les lecteurs estiment que la revue Bulletin de la Dialyse à Domicile met à leur disposition une source d'informations auxquelles ils n'ont pas ou peu accès ailleurs. Elle répond à un besoin, clairement exprimé, pour toutes celles et ceux qui prennent en charge des patients traités par dialyse à domicile mais demeure étroitement lié aux anglophones du fait de la mise en ligne bi linguale. 

β-Glucan as Trained Immunity-Based Adjuvants for Rabies Vaccines in Dogs

The mechanisms of trained immunity have been extensively described in vitro and the beneficial effects are starting to be deciphered in in vivo settings. Prototypical compounds inducing trained immunity, such as β-glucans, act through epigenetic reprogramming and metabolic changes of innate immune cells. The recent advances in this field have opened new areas for the development of Trained immunity-based adjuvants (TIbAs). In this study, we assessed in dogs the potential immune training effects of β-glucans as well as their capacity to enhance the adaptive immune response of an inactivated rabies vaccine (Rabisin®). Injection of β-glucan from Euglena gracilis was performed 1 month before vaccination with Rabisin® supplemented or not with the same β-glucan used as adjuvant. Trained innate immunity parameters were assessed during the first month of the trial. The second phase of the study was focused on the ability of β-glucan to enhance adaptive immune responses measured by multiple immunological parameters. B and T-cell specific responses were monitored to evaluate the immunogenicity of the rabies vaccine adjuvanted with β-glucan or not. Our preliminary results support that adjuvantation of Rabisin® vaccine with β-glucan elicit a higher B-lymphocyte immune response, the prevailing factor of protection against rabies. β-glucan also tend to stimulate the T cell response as shown by the cytokine secretion profile of PBMCs re-stimulated ex vivo. Our data are providing new insights on the impact of trained immunity on the adaptive immune response to vaccines in dogs. The administration of β-glucan, 1 month before or simultaneously to Rabisin® vaccination give promising results for the generation of new TIbA candidates and their potential to provide increased immunogenicity of specific vaccines.

Evaluation of a new rapid-diagnostic test for peritonitis in peritoneal dialysis: the PERIPLEX® device

In 2017, the British company MOLOGIC developed a new rapid-diagnostic test (PERIPLEX®) for the diagnosis of peritonitis in patients undergoing peritoneal dialysis. This single-use test is based on the detection in dialysate of two biomarkers of bacterial infection: Interleukin-6 (IL-6) and matrix metalloproteinase-8 (MMP-8). The test was evaluated in a prospective multicenter study including 10 centers from the RDPLF (French Language Peritoneal Dialysis Registry). A total of 184 tests were performed; 86 tests were negative and 98 were positive. 85 peritonitis were confirmed. There were no false-negatives, and 13 false-positives. Of the 13 false-positives, 7 of them were for sepsis without peritonitis, or peritoneal inflammation. The performance of the test is considered excellent: sensitivity 100%, specificity 86.9%, positive predictive value 86.7%, negative predictive value 100%. In this study, a negative test can formally rule out the diagnosis of peritonitis.

Dialyse péritonéale et pandémie COVID-19

L’épidémie à Coronavirus COVID-19, qui touche la planète entière, oblige chaque pays et leurs habitants à adapter leurs modes de vie afin, à laLfois, de se préserver et de préserver son entourage. La prise en charge des personnes souffrant d’une maladie chronique associée doit évoluer durant cette période en fonction des pathologies et du lieu de traitement. Rapidement, en sus des directives ministérielles, les sociétés savantes ont proposé des recommandations qu’il importe à chacun d’adapter en fonction des possibilités et de l’environnement d’exercice. Certaines sont synthétiques et générales, d’autres concernent des groupes plus particuliers d’individus. Nous citerons ainsi les recommandations (en Anglais) de l’ERA-EDTA :https://www.era-edta.org/en/wp-content/uploads/2020/03/200311_Press-Release_SARS-CoV-2.pdfL’expérience de Wuhan en hémodialyse : https://doi.org/10.1101/2020.02.24.20027201Les recommandations générales de la SFNDT : https://www.sfndt.org/sites/www.sfndt.org/files/medias/documents/Conseils%20SFNDT%20COVID-19%20-%20090320%20vDef.pdf Peu de recommandations étaient fournies concernant les patients traités par dialyse péritonéale en dehors de celles de l’ISPD récemment publiées en plusieurs langues: https://ispd.org/strategies-covid19/ (traduction française réalisée par le RDPLF) La France et certains pays francophones se caractérisent aussi par une proportion importante de patients en dialyse péritonéale non autonomes assistés par infirmière. Les responsables du Registre de Dialyse Péritonéale de Langue Française (RDPLF) ont rédigé, en accord avec la Société Francophone de Néphrologie Dialyse et Transplantation (SFNDT) des recommandations, volontairement simples, et spécifiques du mode de prise en charge dans nos régions. Ces recommandations complètent celles précédemment citées et ne concernent que le suivi du patient lors de son maintien à domicile pour le protéger et protéger son entourage de toute contamination. Il appartient à chaque professionnel de s’inspirer de ces recommandations et de les adapter en fonction de ses possibilités..

Measurement of Hydrostatic Intraperitoneal Pressure: A Necessary Routine Test in Peritoneal Dialysis

This paper summarizes our clinical studies on hydrostatic intraperitoneal pressure (IPP), showing the interest of this measurement in routine clinical practice.

IPP can easily be measured routinely by a simple an d safe method: the measure of the column of dialysate in the peritoneal dialysis (PD) line before drainage, with point 0 located on the midaxillary line. The normal value is 12±2 cm of water (cm H2O) with an intraperitoneal volume (IPV) of 2 L, with linear increases of 2.2 cm H2O for each additional liter.

IPP must be measured to estimate the tolerance of IPV: the maximal permissible IPV is reached for an IPP of 18 cm H2O, squaring with a decrease of 200/0 in vital capacity and sometimes arising before clinical symptomatology. However, IPP measured at rest could not predict PD mechanical complications (hernias, dialysis leakages, hemorrhoids, etc.), which are more dependent on parietal previous history or predisposition.

IPP is significantly higher during the first three days after peritoneal catheter implantation (17±3 cm H2O) than during the 12 following days (10±4 cm H2O). It is recommended to postpone the start of PD until after catheter implantation, and patients should remain supine for the first three days.

On the other hand, IPP strongly reduces the overall ultrafiltration (UF) volume: an increase of 1 cm H2O in IPP caused a decrease of 70 mL in global UF after two hours. Therefore, IPP should be measured in diagnosis of losses of UF. However, UF loss during peritonitis is not due to an increase of IPP.

Impact of First Dialysis Modality on Outcome of Patients Contraindicated for Kidney Transplant

Background

We compared, in patients contraindicated for kidney transplant, outcomes between those patients who were only on hemodialysis (HD) and those who were given peritoneal dialysis (PD) as first renal replacement therapy (RRT).

Design

Prospective, population-based cohort study of incident cases of end-stage renal disease between June 1997 and June 1999.

Setting

A network of dialysis care: NEPHROLOR, that is, all the renal units in Lorraine, one of the 22 French administrative regions (population over 2.3 million people).

Participants

387 patients were contraindicated for kidney transplant during the first 2 years of RRT: 284 were on HD, 103 on PD. Mean age was 67.6 ± 11.3 years for HD patients and 70.8 ± 11.4 years for PD patients ( p = 0.015).

Main Outcome Measures

Mortality until June 2003, hospitalization over the 2 first years of RRT, and Kidney Disease and Quality of Life Short Form (KDQOL-SF) 6 and 12 months after initiation of RRT.

Results

HD patients were more likely to die from cardiac or cerebrovascular causes, PD from cachexia or withdrawal from dialysis. Whatever mode of RRT, the unadjusted 2-year and 5-year survival rates were similar ( p = 0.98). The rate of total duration of hospital stay per month of RRT was similar in HD and PD groups: 2.7 ± 4.5 and 2.9 ± 4.2 days respectively ( p = 0.7). PD was associated with better quality of life than HD. The dimensions Role limitation due to emotional function, Burden of kidney disease, and Role limitation due to physical function ranked first, second, and third for PD.

Conclusion

In Lorraine, end-stage renal disease patients who were given PD as first-line RRT had no excess of death risk or hospitalizations, and better quality of life the first year of RRT.

Characterization of recombinant OspA in two different Borrelia vaccines with respect to immunological response and its relationship to functional parameters

Background

Prevention of Lyme disease in dogs in North America depends on effective vaccination against infection by the tick vector-born spirochete Borrelia burgdorferi. Most vaccines effectively prevent spirochete transmission to dogs during tick feeding based on immunization with the outer-surface lipoprotein A (OspA) of B. burgdorferi. More recently, vaccines containing additional OspC protein moieties have been introduced. These are designed to enhance protection by forming a second line of defense within the vertebrate host, where OspC expression replaces OspA as the dominant surface antigen. However, supportive data for demonstration of OspC mediated protection is still lacking. Since OspA immunogenicity is of paramount importance to protection against spirochete transmission; this study was designed to compare the immunogenicity of two commercially available vaccines against the Borrelia burgdorferi OspA. We further characterized OspA antigen fractions of these vaccines with respect to their biochemical and biophysical properties.

Results

Two groups of beagle dogs (n = 9) were administered either: (1) a nonadjuvanted/monovalent, recombinant OspA vaccine (Recombitek® Lyme) or (2) an adjuvanted, recombinant OspA /OspC chimeric fusion vaccine (Vanguard® crLyme). The onset of the anti-OspA antibody response elicited by the nonadjuvanted/monovalent OspA vaccine was significantly earlier than that for the bivalent OspA /OspC vaccine and serum borreliacidal activity was significantly greater at all post-vaccination time points. As expected, only dogs inoculated with the bivalent OspA/OspC vaccine mounted a humoral anti-OspC response. However, only three out of nine dogs in that group had a positive response. Comparison of the OspA vaccine structures revealed that the OspA in the nonadjuvanted/monovalent vaccine was primarily in the lipidated form, eluting (SEC-HPLC) at a high molecular weight, suggestive of micelle formation. Conversely, the OspA moiety of the OspA/OspC vaccine was found to be nonlipidated and eluted as the monomeric protein.

Conclusions

We hypothesize that these structural differences may account for the superior immunogenicity of the nonadjuvanted monovalent recombinant OspA vaccine in dogs over the adjuvanted OspA fraction of the OspA/OspC vaccine.

Partager son expérience et connaissances pour la dialyse à domicile

Le besoin d’un accès facile, à la portée de tous, de l’information scientifique, a conduit ces dernières années à l’apparition de nombreuses revues directement consultables par Internet. La qualité de l’information est garantie dès lors que les articles qui y sont publiés sont soumis à l’analyse critique d’un comité de lecture par les experts reconnus dans son domaine. Dès 1995, le RDPLF a disposé du Bulletin de Dialyse Péritonéale (BDB) qui était publié 4 fois par an jusqu’au début des années 2000. Les anciens numéros peuvent encore être consultés sur son site. Néanmoins pour différentes raisons, dont les coûts d’impression nous avions dû ensuite restreindre l’édition de cette revue à tous les deux ans pour les résumés du Symposium.Nous avons pensé que l’heure était venue d’actualiser le recours à ce media sous une forme moderne : le libre accès par Internet (connu sous le terme « Open Access »). Depuis le RDPLF a évolué et est devenu en pratique RDPLF-HDD puisque nous incluons maintenant toutes les méthodes de domicile. Pour souligner cet aspect le nom de la revue est changé en Bulletin de Dialyse à Domicile (BDD).Le BDD sera publié en accès libre une fois par trimestre pour commencer et le rythme évoluera en fonction des besoins. Il comportera différentes sections : Editorial, Résultats du RDPLF, articles de formation pratique, articles cliniques d’intérêt général, etc..le but dans l’ensemble est d’occuper une place qui n’est pas forcément assurée par d’autres revues, délibérément tournée vers la pratique du domicile, ce qui n’exclue pas de temps en temps des travaux plus fondamentaux que des auteurs accepteraient de partager en accès libre.Les articles seront indexés par un numéro DOI. Nous souhaitons aussi par ce moyen, donner la possibilité à des néphrologues et infirmières qui le souhaitent les moyens d’une publication rapide de leurs travaux.Pour assurer la qualité des documents, ils seront tous soumis à un comité de lecture dont la composition est disponible sur ce site dans la rubrique a propos.C’est à vous, néphrologues et infirmières qui traitez des patients en dialyse à domicile, qu’il appartient, par vos futurs articles, d’assurer le succès de ce projet.Vous pouvez dès maintenant nous soumettre directement vos articles, soit en vous inscrivant sur le site, soit en nous les adressant pas mail ou courrier. Merci d'avance, pour nos patients, à tous ceux et celles qui nous aideront.

Microbiota Quality and Mitochondrial Activity Link with Occurrence of Muscle Cramps in Hemodialysis Patients using Citrate Dialysate: A Pilot Study

BACKGROUND/AIMS

Hemodialysis-associated muscle cramp (HAMC) is a common complication under citrate dialysate (CD) occurring in 30% of cases. Our objectives were to assess the gut microbiota quality, mitochondrial activity, and to investigate their possible relationship with HAMC.

METHODS

Ten end-stage renal disease patients (78.9 ± 2.1 years) treated by hemodialysis (HD) with CD were enrolled and then classified according to the frequency of HAMCs: "frequent HAMCs group" (n = 5) and "absence of HAMCs group" (n = 5). Gut microbiota quality, mitochondrial activity, and some markers of oxidative stress (OS) were investigated.

RESULTS

In patients with cramps, gut microbiota diversity seemed lower and some genera including Helicobacter, Lachnospira, Roseburia, and Haemophilus seemed over-expressed, a significant increase of citratemia and significant lowering mitochondrial function were observed. No difference was observed on the OS markers.

CONCLUSION

This first clinical study revealed a possible dysbiosis of microbiota and a mitochondrial dysfunction into HD patients with cramps under CD compared to patients without cramp.

Intraluminal stone in a PD catheter : third world case

Only 2 cases of intraluminal peritoneal catheter lithiasis have been reported so far. A woman (68 years of age) on CAPD was admitted to hospital because of intermittent outflow obstruction of her peritoneal catheter. A stone was found in the catheter lumen. Its biochemical composition was the same as that of the 2 other cases previously described: calcium-hydroxycardonate-phosphate with an admixture of protein. The stone could not migrate through the intraperitoneal tip hole of the catheter because its size (3 x 4 mm) was greater than the catheter lumen (2.7 mm). That suggests in situ development, directly in the catheter lumen despite inflow-outflow dialysate daily regular rinsings. In the 3 cases, dialysate contained lactate and 1.75 mmol/L calcium.

An African horse sickness virus serotype 4 recombinant canarypox virus vaccine elicits specific cell-mediated immune responses in horses

A recombinant canarypox virus vectored vaccine co-expressing synthetic genes encoding outer capsid proteins, VP2 and VP5, of African horse sickness virus (AHSV) serotype 4 (ALVAC(®)-AHSV4) has been demonstrated to fully protect horses against homologous challenge with virulent field virus. Guthrie et al. (2009) detected weak and variable titres of neutralizing antibody (ranging from <10 to 40) 8 weeks after vaccination leading us to hypothesize that there could be a participation of cell mediated immunity (CMI) in protection against AHSV4. The present study aimed at characterizing the CMI induced by the experimental ALVAC(®)-AHSV4 vaccine. Six horses received two vaccinations twenty-eight days apart and three horses remained unvaccinated. The detection of VP2/VP5 specific IFN-γ responses was assessed by enzyme linked immune spot (ELISpot) assay and clearly demonstrated that all ALVAC(®)-AHSV4 vaccinated horses developed significant IFN-γ production compared to unvaccinated horses. More detailed immune responses obtained by flow cytometry demonstrated that ALVAC(®)-AHSV4 vaccinations induced immune cells, mainly CD8(+) T cells, able to recognize multiple T-epitopes through all VP2 and only the N-terminus sequence of VP5. Neither VP2 nor VP5 specific IFN-γ responses were detected in unvaccinated horses. Overall, our data demonstrated that an experimental recombinant canarypox based vaccine induced significant CMI specific for both VP2 and VP5 proteins of AHSV4.

Blockade of LTB(4) /BLT(1) pathway improves CD8(+) T-cell-mediated colitis

BACKGROUND

Leukotriene B4 (LTB(4) ) has chemotactic properties for activated T cells expressing the high-affinity receptor BLT(1) . This study investigated whether the LTB(4) antagonist (CP-105,693), selective for BLT(1) receptor, could protect mice from colitis mediated by specific cytotoxic CD8(+) T lymphocytes (CTL).

METHODS

Virus-specific colitis was induced in C57Bl/6 mice transferred with lymphoid cells from P14 TcR Tg mice which are specific to class I GP33 peptide of LCMV. Mice were immunized with GP33-pulsed dendritic cells and colitis was elicited by intrarectal administration of the peptide. Colitis was evaluated by body weight loss and macroscopic and histological analysis of colon. In vivo priming of specific CD8(+) CTL was determined using interferon (IFN)-γ ELISPOT and in vivo CTL assays. In some experiments mice were treated with a selective LTB(4) receptor antagonist.

RESULTS

Immunization with GP33-pulsed dendritic cells (DCs) induced priming of specific CD8(+) CTL, as shown by the presence of IFN-γ-producing CD8(+) T cells in colon draining lymph nodes and in vivo CTL assays. Intrarectal challenge with GP33 induced severe colitis and recruitment of granzyme B(+) P14 CD8(+) cells in colon. Treatment with the specific LTB(4) receptor antagonist before elicitation of colitis reduced the severity of colitis and decreased the frequency of specific effectors.

CONCLUSIONS

Colitis can be induced by IFN-γ-producing cytotoxic CD8(+) CTL specific for viral antigen. Blockade of the LTB(4) /BLT(1) pathway by a selective BLT(1) receptor antagonist attenuates colitis by inhibiting CD8(+) effectors recruitment in colon. These data illustrate the therapeutic potential of LTB(4) receptor selective antagonists in protection from CD8(+) T-cell-mediated intestinal inflammation.

CD4+ T cells and Lactobacillus casei control relapsing colitis mediated by CD8+ T cells

Evidence that CD4(+) regulatory T cells can control Ag-specific CD8(+) T cell-mediated colitis in immunocompetent mice is poorly documented. To examine the potential of CD4(+) T cells to control colitis, we used our model of CD8(+) T cell-mediated colitis induced by intracolonic sensitization followed by challenge with the hapten 2,4-dinitrobenzene sulfonic acid. The defect of CD4(+) T cells in MHC class II-deficient (Abeta(degrees/degrees)) mice allowed priming of 2,4-dinitrobenzene sulfonic acid-specific IFN-gamma-producing CD8 colitogenic effectors and development of colitis in the otherwise resistant C57BL/6 strain. Cotransfer experiments in RAG2(degrees/degrees) mice and ex vivo studies showed that CD4(+)CD25(+) T cells completely prevented CD8(+) T cell-mediated colitis and controlled CD8(+) T cell activation, respectively. In the susceptible BALB/c strain, Ab depletion revealed that lack of CD4(+) regulatory T cells resulted in 1) acute colitis elicited by a suboptimal dose of hapten challenge and 2) more severe relapsing episodes of colitis induced by effector/memory CD8(+) T cell-mediated colitis at an optimal dose of hapten challenge, even when CD4 depletion was performed just before the second challenge. Oral administration of the probiotic strain Lactobacillus casei DN-114 001 alleviated colitis and increased the suppressive function of Foxp3(+)CD4(+) regulatory T cells of colon lamina propria. These data demonstrate that CD4(+) regulatory T cells exert a protective effect on colitis by controlling colitogenic effector/memory CD8(+) T cells during the effector (symptomatic) phase of acute and relapsing colitis, respectively. Probiotics with natural adjuvant effects on mucosal regulatory T cells may represent a valuable approach to alleviate the colitogenic effect of Tc1-type CD8(+) effectors.

Regional discrepancies in peritoneal dialysis utilization in France: the role of the nephrologist's opinion about peritoneal dialysis

BACKGROUND

Peritoneal dialysis (PD) is underused in France compared with other countries. In addition, there are tremendous regional discrepancies concerning the utilization rate of PD. This study was carried out to evaluate the opinion of French nephrologists regarding the optimal rate of PD utilization and to determine which factors limit PD development in France.

METHODS

Of the 22 French regions, 2 regions with a high rate of PD utilization (prevalence >15%) and 3 regions with a low rate of PD utilization (prevalence <10%) were selected. In June 2007, nephrologists from the five regions were surveyed by questionnaire. Responses were compared between 'low-prevalence' and 'high-prevalence' groups.

RESULTS

The response rate was 70% and there was no significant difference between the two groups regarding the response rate. In the two groups, a majority of nephrologists were in charge of PD patients (30/34 in 'high-prevalence' group versus 61/80 in 'low-prevalence' group, P = 0.14). Information about PD in the predialysis clinics was provided by nephrologists from high- and low-prevalence regions (32/34 versus 65/80, P = 0.08). Opinions on the optimal rate of PD for prevalent and incident dialysis patients were significantly different between 'high-prevalence' and 'low-prevalence' groups [31 +/- 15% versus 25 +/- 14% (P < 0.03) and 25 +/- 14% versus 19 +/- 9% (P < 0.02)]. There was a significant difference concerning the optimal rate of PD in incident dialysis patients between nephrologists working in public centres (29 +/- 15%), those working in non- profit clinics (27 +/- 12%) and nephrologists working in the private sector (14 +/- 8%). Lack of nurses available for the patient care (48%), low reimbursement of PD (25%), limited training (23%) and hospital care facilities (23%) were the main barriers limiting PD utilization.

CONCLUSIONS

In France, like in other countries, there are factors limiting PD development; however, regional discrepancies regarding PD utilization seem to be linked to the nephrologist's opinion.

Influence of autonomy and type of home assistance on the prevention of peritonitis in assisted automated peritoneal dialysis patients. An analysis of data from the French Language Peritoneal Dialysis Registry

BACKGROUND

In France, 48% of home-based peritoneal dialysis (PD) patients require assistance to perform their exchange and manage their treatment. A total of 7% are aided by their family, and 41% by a private nurse. Of all the continuous ambulatory peritoneal dialysis (CAPD) patients, 61.7%, and among automated peritoneal dialysis (APD) patients 23%, are assisted at home for their bag exchanges and connections. Assisted APD patients (AAPD) are more comorbid and elderly so that a home helper is not always available: this explains why most helpers at home are private visiting nurses paid by the National Social Security. In addition to the home helper (nurse or family), 58% of centres make regular additional home visits to check the respect of procedures previously taught during the initial training of the nurse or the family helper. The aim of this study was to evaluate whether the type of home assistance received by dependent patients had an influence on peritonitis rates, and if home visits done by nurses of training centres may improve results.

METHODS

Peritonitis rates and the probability of being peritonitis free were analysed for 1624 new APD patients recorded in the French PD Registry (RDPLF) between 2000 and 2004, and followed-up until early 2005.

RESULTS

Nurse-assisted APD patients had a peritonitis rate of one episode every 36 months, and family-assisted patients one episode every 45 months; using Poisson analysis this trend was not significant (P=0.11). However, the probability of being peritonitis free was significantly higher for family-assisted (69.8% at 2 year) compared with home nurse-aided persons (54.4%) after adjustment for age, diabetes and the Charlson comorbidity index. This difference disappeared when nurses from the training centre regularly visited PD patients at their home in the presence of their helper, whichever type of assistance they received. In addition, when the nurses from the training centres visited private nurse-assisted patients, the probability of being peritonitis free was significantly improved in comparison with those persons who did not receive home visits, from 33.9% to 50.8% at 3 years (P=0.028).

CONCLUSIONS

APD patients assisted at home by a private nurse have a higher risk of developing peritonitis than family-assisted patients, unless additional regular home visits are organized by the original training centre. Therefore, we recommend that home visits be regularly made for dependent PD patients to optimize the quality of care provided by the helper.

[Iron therapy: is it different with peritoneal dialysis compared to haemodialysis?]

This paper reviews literature data on iron replacement (loading) for peritoneal dialysis patients. The 3 main sources of clinical guidelines (American NKF-K/DOQI, European EBPG and French AFSSAPS) agree about the definition of iron deficience, but are not similar about the haemoglobin/hematocrit targets for EPO treatment, and for the route of iron administration (oral versus intravenous). Iron requirements are less in PD HD patients. That could be explained by several factors: less blood losses, preservation of a residual renal function, better digestive iron absorption due to a greater hepcidin excretion. Intravenous route for iron sucrose is more efficient than oral route. Taking into account the iron requirements for PD patients, monthly 200 mg iron sucrose infusions over 5 mn seem to be safe and sufficient for most patients.

APD schedules and clinical results

This chapter exposes the clinical effects of different APD schedules. Clinical studies have shown that Na removal is lower with APD compared to CAPD. Therefore the loss of residual renal function requires continuous therapy with long day-dwell of polyglucose dialysate. Peritoneal small molecule clearances are closely determined by the hourly dialysate flow rate (and not the dwell time, which is a concept coming from equilibrium PD techniques as CAPD) with a maximum reached by 3 l/h for average transporter patients. On the other hand, the optimal intraperitoneal volume should be 1500 ml/m(2) of BSA, and less if the hydrostatic intraperitoneal pressure is higher than 18 cm H(2)O. The optimization of the nocturnal APD session depends on the knowledge of the individual drain flow profile. A new schedule, called 'BreakPoint-APD' is based on the automatic adaptation to the drain profile for each patient and for each cycle. It increases clearances by about 10% compared to tidal and CCPD, though reducing the number of nocturnal alarms. The future of APD is likely to continue thanks to further simplification in the machine use, i.e. with improvements in cycler technology.

Surfactant-free anionic PLA nanoparticles coated with HIV-1 p24 protein induced enhanced cellular and humoral immune responses in various animal models

Microparticles and nanoparticles prepared with poly(D,L-lactide-co-glycolide) (PLGA) or poly(D,L-lactide) (PLA) polymers represent a promising method for in vivo delivery of encapsulated peptide, protein or DNA antigens. However, one major issue that limits the potential of these delivery systems is the instability or the degradation of the entrapped antigen. Charged microparticles carrying surface adsorbed antigen were developed to resolve this problem and appear more suitable for vaccine applications. We describe here new anionic PLA nanoparticles obtained by the dialysis method that are absolutely surfactant-free, which makes them more appropriate for use in humans. The potency of this delivery system as a vaccine carrier was tested in various animal models using HIV-1 p24 protein. p24-coated PLA nanoparticles (p24/PLA) induced high antibody titres (>10(6)) in mice, rabbits and macaques. Moreover, p24/PLA nanoparticles elicited strong CTL responses and a Th1-biased cytokine release (IFNgamma, IL-2) in mice. p24 protein seemed to generate a more Th1-oriented response when administered coated onto the surface of PLA nanoparticles than adjuvanted with Freund's adjuvant. Most importantly, the ability of p24/PLA particles to induce Th1 responses was also confirmed in the macaque model, since high levels of IFNgamma-producing CD4+ T cells and CD8+ T cells could be detected by the ELISPOT assay. This protein delivery system confirms the potential of charged nanoparticles in the field of vaccine development.

Impact of first dialysis modality on outcome of patients contraindicated for kidney transplant

BACKGROUND

We compared, in patients contraindicated for kidney transplant, outcomes between those patients who were only on hemodialysis (HD) and those who were given peritoneal dialysis (PD) as first renal replacement therapy (RRT).

DESIGN

Prospective, population-based cohort study of incident cases of end-stage renal disease between June 1997 and June 1999.

SETTING

A network of dialysis care: NEPHROLOR, that is, all the renal units in Lorraine, one of the 22 French administrative regions (population over 2.3 million people).

PARTICIPANTS

387 patients were contraindicated for kidney transplant during the first 2 years of RRT: 284 were on HD, 103 on PD. Mean age was 67.6 +/- 11.3 years for HD patients and 70.8 +/- 11.4 years for PD patients (p = 0.015).

MAIN OUTCOME MEASURES

Mortality until June 2003, hospitalization over the 2 first years of RRT, and Kidney Disease and Quality of Life Short Form (KDQOL-SF) 6 and 12 months after initiation of RRT.

RESULTS

HD patients were more likely to die from cardiac or cerebrovascular causes, PD from cachexia or withdrawal from dialysis. Whatever mode of RRT, the unadjusted 2-year and 5-year survival rates were similar (p = 0.98). The rate of total duration of hospital stay per month of RRT was similarin HD and PD groups: 2.7 +/- 4.5 and 2.9 +/- 4.2 days respectively (p = 0.7). PD was associated with better quality of life than HD. The dimensions Role limitation due to emotional function, Burden of kidney disease, and Role limitation due to physical function ranked first, second, and third for PD.

CONCLUSION

In Lorraine, end-stage renal disease patients who were given PD as first-line RRT had no excess of death risk or hospitalizations, and better quality of life the first year of RRT.

The efficacy and safety of once-weekly and once-fortnightly subcutaneous epoetin β in peritoneal dialysis patients with chronic renal anaemia

BACKGROUND

Reducing the dosage frequency of subcutaneous epoetin in peritoneal dialysis (PD) patients is convenient and should improve patient satisfaction and, possibly, compliance. We investigated if a weekly dosage of epoetin beta in PD patients safely maintained haemoglobin (Hb) concentrations equivalent to those obtained with previous twice- or thrice-weekly administration. In addition, we investigated if a fortnightly dosage of epoetin beta was safe and as effective as previous weekly administration.

METHODS

After a 4 week run-in period, PD patients were switched to either weekly or fortnightly epoetin beta administration, depending on their previous treatment schedules, for 25 weeks.

RESULTS

The per-protocol cohort included 128 patients, of whom 54 received epoetin beta once weekly and 74 once fortnightly. The mean change in Hb concentration from baseline over weeks 13-25 and the 90% confidence intervals (CIs) remained within the target range (10-12 g/dl) and specified equivalence (+/-0.75 g/dl) limits in the weekly (-0.34 g/dl; 90% CI: -0.14 to -0.54 g/dl) and fortnightly (-0.39 g/dl; 90% CI: -0.24 to -0.55 g/dl) cohorts. The mean change from baseline in the epoetin beta dose was 1.4 IU/kg/week (90% CI: -3.8 to 6.6 IU/kg/week; 2%) in the weekly cohort and 4.4 IU/kg/week (90% CI: 1.7-7.2 IU/kg/week; 13%) in the fortnightly cohort. Both treatment regimens were well tolerated.

CONCLUSIONS

In stable PD patients switched from twice- or thrice-weekly to weekly epoetin beta treatment, Hb concentrations could be maintained within the specified range over 25 weeks without significant change in their mean epoetin beta doses. In patients switched from weekly to fortnightly treatment, Hb concentrations could also be maintained over 25 weeks. There was a small increase in the mean dose during this period, but >/=50% of patients could be maintained without dose increase. Reducing dosage frequency may improve compliance in PD patients who self-administer their epoetin.

[Infection peritonitis in patients undergoing continuous ambulatory peritoneal dialysis: microbiological review during an four-year period]

The purpose of this study was to analyse the microbiological characteristics of infectious peritonitis in patients undergoing continuous ambulatory peritoneal dialysis. This study was conducted at the CHU Nancy from 1999 to 2002. The diagnosis of peritonitis was based on cloudy peritoneal effluent (>100 cells per mm(3)) with an elevated leukocyte count (>50%), on isolation of bacteria or fungi and on symptoms such as abdominal discomfort or pain. The majority of infections associated with continuous ambulatory peritoneal dialysis were caused by Gram-positive bacteria (68%), Gram-negative bacteria (31%), and Candida (1%). The coagulase-negative staphylococci were the most common cause of peritonitis. The antibiotic sensitivity of species corresponded to community-acquired isolation.

Short communication: retrospective study to time the introduction of HIV type 1 non-B subtypes in Lyon, France, using env genes obtained from primary infection samples

Using blood samples from primary HIV-1 infection (PHI) patients obtained in Lyon, France, we characterized the newly transmitted HIV-1 variants in this area during the 1992-1996 period. As PHI samples allowed the precise timing of the transmission event, we were able to date the introduction of non-B subtypes or recombinant forms of the virus in Lyon. Genomic DNA from 18 HIV-1-positive patients at primary infection was used to amplify the full-length env gene by nested PCR; after cloning, the gene was sequenced for subsequent phylogenetic analysis. Several non-B subtypes and recombinant forms of HIV-1 were identified among the 18 patients studied (1 subtype F1, 1 CRF01-AE, 2 subtype G and 2 CRF02-AG). We also found a new J/K recombinant form transmitted in 1995 and never described until now. The introduction of CRF02-AG in Lyon, France, occurred prior to 1992 and six transmission events including non-B subtypes were documented in the following 4 years. Heterosexual contacts appeared as the main introduction pathway for non-B subtypes or recombinant forms. Nevertheless, as transmission of these viruses occurred not only during travel to endemic regions, but also in France or Germany, we conclude that non-B strains entered Europe before the studied period. This retrospective study showed that even if subtype B remained prevalent in the spreading HIV-1 infection in Lyon between 1992 and 1996, non-B subtypes and circulating recombinant forms represented a significantly growing part.

Evaluation in rhesus macaques of Tat and rev-targeted immunization as a preventive vaccine against mucosal challenge with SHIV-BX08

Recent evidence suggests that a CD8-mediated cytotoxic T-cell response against the regulatory proteins of human immunodeficiency virus (HIV) or simian immunodeficiency virus (SIV) may control infection after pathogenic virus challenge. Here, we evaluated whether vaccination with Tat or Tat and Rev could significantly reduce viral load in nonhuman primates. Rhesus macaques were primed with Semliki forest Virus (SFV) expressing HIV-1 tat (SFV-tat) and HIV-1 rev (SFV-rev) and boosted with modified vaccinia virus Ankara (MVA) expressing tat and rev. A second group of monkey was primed with SFV-tat only and boosted with MVA-tat. A third group received a tat and rev DNA/MVA prime-boost vaccine regimen. Monitoring of anti-Tat and anti-Rev antibody responses or antigen-specific IFN-gamma production, as measured by enzyme-linked immunospot assays revealed no clear differences between the three groups. These results suggest that priming with either DNA or SFV seemed to be equivalent, but the additive or synergistic effect of a rev vaccine could not be clearly established. The animals were challenged by the rectal route 9 weeks after the last booster immunization, using 10 MID(50) of a SHIV-BX08 stock. Postchallenge follow-up of the monkeys included testing seroconversion to Gag and Env antigens, measuring virus infectivity in PBMC by cocultivation with noninfected human cells, and monitoring of plasma viral load. None of the animals was protected from infection as assessed by PCR, but peak viremia was reduced more than 200-fold compared to sham controls in one third (6/18) of vaccinated macaques, whatever the vaccine regimen they received. Interestingly, among these six protected animals four did not seroconvert. Altogether, these results clearly indicated that the addition of early HIV proteins like Tat and Rev in a multicomponent preventive vaccine including structural proteins like Env or Gag may be beneficial in preventive vaccinal strategies.

Evaluation of low-pressure arterial and venous clamps: electron microscopic study and possible clinical applications

These authors report on validating their choice of disposable clamps in arterial and venous microsurgery in a comparative and experimental study using the scanning electron microscope. This appears to be the first evaluation of venous endothelial clamping lesions. Early intimal clamping lesions were studied using three different clamps and two protocols in 18 femoral arteries and veins in rabbits. Results were evaluated using a new classification that can be applied to both arterial and venous lesions: Grade I: cellular disorientation and disorganization; endothelial lamination; and absent or very few platelet deposits; Grade II: alterations of the cytoplasmic membranes in fusiform cells; presence of at least one breach of endothelial continuity; and moderate number of platelet deposits; Grade III: presence of endothelial detachment; and large numbers of platelet deposits. They showed that in arteries, all the clamps tested caused only low-grade lesions. In contrast, in veins, they demonstrated both the very fragile nature of the endothelium, and also the comparative safety of the low-pressure venous clamp. Their choice of specific clamps for venous anastomoses was validated.

Mobilization of lead from bone in end-stage renal failure patients with secondary hyperparathyroidism

BACKGROUND

It is now recognized that long-term exposure to even low levels of lead may increase bone lead content. Lead can then be released in toxicologically significant amounts during critical states of increased bone turnover.

METHODS

Two patients with end-stage renal failure, one on haemodialysis and the other on continuous ambulatory peritoneal dialysis (CAPD), had been exposed to lead and developed secondary hyperparathyroidism. An edetate calcium disodium (EDTA) test was performed in combination with haemofiltration or CAPD before and after parathyroidectomy.

RESULTS

Before parathyroidectomy, both patients had low delta aminolaevulinic acid dehydrase (ALA-D) and high concentrations of chelated lead. After parathyroidectomy, there was a dramatic decrease in chelated lead and the ALA-D returned to normal.

CONCLUSION

Secondary hyperparathyroidism increases mobilization of bone lead in dialysis patients with an elevated lead burden. This may cause toxic effects.

[Adequate peritoneal dialysis: limitations of continuous ambulatory peritoneal dialysis (CAPD), place of automated peritoneal dialysis (APD)]

Recent epidemiological studies show a slowing down of the global growth of CAPD which is not compensated by the considerable development of APD. These modifications are the result of the arrival of technologies which allow new strategies as well as an improved knowledge of the adequate dialysis dose for PD. The re-evaluation of the adequate clearance targets show that CAPD does not deliver an adequate dialysis dose for anuric patients but it remains an excellent technique for patients with residual renal function. APD and mixed techniques (APD with automated diurnal exchange(s), CAPD with automated nocturnal exchange) can deliver an adequate dialysis dose if the peritoneal permeability is not too low and if the prescription is adapted to each patient. The growth of CAPD seems to be slowing down due to a better knowledge of its limitations. However the development of APD does not seem to be related to the increasing knowledge of its possibilities. The development of automated techniques, prescribed as substitute treatments, depends on a precise evaluation of the cost/efficiency/quality of life index, compared to the reference treatment which is iterative hemodialysis.

Intraperitoneal hydrostatic pressure and ultrafiltration volume in CAPD

The intraperitoneal hydrostatic pressure (IPP) and overall ultrafiltration (UF) volume were measured in 34 patients after a 2-hour exchange with 2 L of dialysate containing 3.86% glucose. These patients had been treated with continuous ambulatory peritoneal dialysis (CAPD) on average for 26 +/- 20 months under stable conditions. The patients were at rest during the 2-hour exchange. The normal IPP measured with the patient lying completely flat was on inspiration (IPPinsp) 14 +/- 4 cm of water (cmH2O) and on expiration (IPPexp) 12 +/- 3 cm H2O, for an intraperitoneal volume of 2820 +/- 319 mL. The mean UF was 744 +/- 323 mL. The mean IPP (IPPmean), defined by (IPPinsp+IPPexp)/2, had a negative linear correlation to the UF volume (r = 0.66; p = 0.0001). The linear regression test showed that an increase of 1 cm H2O in the IPPmean reduced the overall UF volume by 70 mL in 2 hours. In conclusion, even though the UF is produced by the osmotic pressure of the dialysate, it is also influenced to a great extent by the intraperitoneal hydrostatic pressure, which should not be ignored.

Diagnosis and treatment of chronic lead poisoning in CAPD patients

In order to screen for abstruse lead poisoning in continuous ambulatory peritoneal dialysis (CAPD) patients, delta-aminolevulinic acid dehydratase (ALAD) levels were measured in 18 CAPD patients, 156 patients treated with hemodialysis (HD), and 420 control patients with normal renal function (NRF). An EDTA (ethylenediamine tetraacetic acid) mobilization test was performed in patients with low levels of ALAD (< 0.40 mumol of porphobilinogen formed per milliliter of red blood cells): 1 g of EDTA was infused IV followed by 20 L of hemofiltrate in HD patients and four bags of dialysate in CAPD patients. Lead was assayed in the ultrafiltrate liquid, the bags of dialysate, and in the 24-hour urine. ALAD levels were significantly lower in CAPD and HD patients than in the NRF subjects. ALAD was significantly correlated with EDTA mobilized lead in both dialysis and NRF patients. Using the usual criteria (EDTA mobilized lead > 800 micrograms/24 hours), the rate of lead poisoning observed was similar in the two groups. These results suggest that ALAD assay followed by the EDTA mobilization test is as effective in CAPD patients as in NRF subjects to diagnose and to treat chronic abstruse lead poisoning.