The effect of exosomes released from apheresis platelet concentrates under the impact of gamma irradiation and storage time upon platelet aggregation and hemostasis.

BACKGROUND: Blood components should be gamma-irradiated (γ-IR) in order to prevent transfusion-associated graft-versus-host disease. The aim of this study is to determine the effect of γ-IR and storage time on the exosomes released from apheresis platelet concentrates (aPC) and to investigate their impact on the maximum platelet aggregation (MPA) and hemostasis. MATERIALS AND METHODS: Eight units of aPC were included in this study. These were divided into four equal portions. Two portions were irradiated before storage while the other two were not. Thus, irradiated and non-irradiated aPC samples for storage Days 0 (D0) and 5 (D5) were obtained. Exosomes were isolated from these samples using a commercial kit and were evaluated to ascertain their parent cells by flow cytometry. For the following steps, exosomes were pooled according to their features. Pooled exosomes were then used for aggregometry and thromboelastography. RESULTS: Platelet-derived exosome (PD-EX) levels decreased in D5 compared to D0 in NI-aPC, whereas granulocyte-derived exosome (GD-EX) levels increased. Exosome pools had no effect on MPA compared to saline groups. Exosome pools decreased the time to initial fibrin formation (R), whereas they increased the rate of clot formation (α-angle) and coagulation index (CI) compared to saline groups. DISCUSSION: Storage time and γ-IR each have almost the opposite effects on PD-EX and GD-EX. Exosomes have no impact on MPA, but enhance the clot strength. The impact of exosomes on aPC quality and effectiveness can be ignored or considered as a positive effect.

Effect of storage period of red blood cell suspensions on helper T-cell subpopulations.

BACKGROUND: The aim of this study was to investigate the immunological alterations that occur during the storage of erythrocyte suspensions which may lead to transfusion-related immunomodulation following allogeneic blood transfusion. MATERIALS AND METHODS: One part of the erythrocyte suspensions obtained from donors was leucoreduced while the other part was not. The leucoreduced (LR) and non-leucoreduced (NL) erythrocyte suspensions were then further divided into three equal amounts which were stored for 0, 21 or 42 days prior to measurements, by enzyme-linked immunosorbent assays, of cytokine levels in their supernatants. T-helper (Th) lymphocyte subgroups and gene expression were analysed in the NL erythrocyte suspensions by flow cytometry and real-time polymerase chain reaction, respectively. Results were compared to those of storage day 0. RESULTS: By day 21, the number of Th2 cells had increased significantly and the numbers of Th1, Th22 and Treg cells had decreased significantly in the NL erythrocyte suspensions. On day 42 the numbers of Th2 and Treg cells in the NL suspensions were significantly increased while the number of Th1 cells was significantly decreased. The levels of transcription factors (TBX21, GATA3, and SPI.1) were significantly decreased on days 21 and 42, and AHR, FOXP3 and RORC2 levels were significantly increased on day 42 in NL erythrocyte suspensions. The decrease in interleukin-22 and increase in transforming growth factor-ß levels found in NL erythrocyte suspensions on day 21 were statistically significant. Elevated levels of interleukin-17A were found in both LR and NL erythrocyte suspensions on day 42. DISCUSSION: Our results suggest that allogeneic leucocytes and cytokines may play significant roles in the development of transfusion-related immunomodulation.

[Hospital hygiene and antibiotherapy counselling: an operational dual solution against the spreading of multiresistant bacteria]. / L'hygiène hospitalière et le conseil en antibiothérapie: un duo opérationnel face au problème de la diffusion des bactéries multirésistantes aux antibiotiques.

OBJECTIVES: The authors had for aim to show that preventing the diffusion of multidrug-resistant organism (MRO) is possible thanks to the coordination of recommended preventive actions and the implementation of a sensible anti-infective prescription policy. They also wanted to highlight the role played by the nursing care staff in enforcing recommendations. METHOD: We compared the results of two health care facilities having both implemented the same strategy aimed at preventing cross-transmission and prescribing anti-infective drugs. RESULTS: Audits reported a very variable enforcement of recommendations. The results obtained from microbiological monitoring confirmed the essential impact of protocol enactment by every team, on the control of MRO diffusion. The antibiotherapy specialist has a key role in the suggested strategy, allowing a significant decrease in the number of anti-infective prescriptions and a more rational use. CONCLUSION: The collaboration of a hygiene specialist with an antibiotherapy specialist has proved operational in the fight against MRO diffusion, as long as the competences of both specialists are acknowledged and their cross-disciplinary activities accepted. For the entire staff, enacting a corporate culture is a crucial asset.

[Prospective assessment of glycopeptides prescriptions in a general hospital]. / Evaluation prospective de la prescription des glycopeptides dans un hôpital général.

OBJECTIVE: The authors had for aim to analyze the indications, quality, and volumes of glycopeptide (GP) prescriptions in all in-patient units of a general hospital. CLINICAL MATERIAL AND METHODOLOGY: A 4 month prospective study assessed the compliance of curative and prophylactic treatment prescriptions administered according to guidelines. The assessment criteria were as follows: prescription indicated or not, prescription modalities (administration of loading dose, performing of serum tests, dosage appropriateness, appropriateness with antibiogram data when available). RESULTS: Over the 46 assessed prescriptions, 84.7% were curative treatments (N = 39), whereas 15.2% (N = 7) were written out for surgical antibioprophylaxis. The prescription incidence and density were, respectively, 0.60 prescription/100 admissions and 20.8 DDJ/1000 hospitalization days, i.e. 24% of the total antibiotics budget. Prescriptions were always indicated for surgical antibioprophylaxis, but met standards in only 14% of cases. As for curative prescriptions, treatments were appropriate in 56.5% of cases, but only 18% met standards. GP use modalities proved incorrect at various levels: non existing load dose and lack of serum tests, subinhibiting daily doses, no dose lowering when possible, exaggerated duration of surgical antibioprophylaxis. Average GP serum levels were 16 mg/L and were higher than the target level in no more than 40% of properly prescribed treatments. CONCLUSION: Prescription modalities and treatment monitoring must be improved, given the development of bacterial resistance.

Does high antibiotic consumption still reflect bad practices?

OBJECTIVE: The authors had for aim to assess the quality of antibiotic prescription in an intensive care unit because of their high rate of consumption. DESIGN: A prospective 5-month study was made of the first 50 prescriptions of ciprofloxacin, levofloxacin, teicoplanin, vancomycin, and imipenem. Treatment was considered adequate at day 5 if the indication was relevant, with the right doses, and if the prescription was adapted to the antibiogram. RESULTS: Fifty treatments were evaluated (38 patients included). Eighty-four percent (42/50) was adequate at day 5. Glycopeptides and fluoroquinolones accounted for 2/3 of prescriptions. The absence of de-escalation was the most common mistake. The severity of presentations was evident with a mean SSI at 68 (22-113), and a mean BMI at 28 (18.5 - 50). Eighty-four percent (32/38) of patients were exposed to invasive devices, 47% died in the ICU. DISCUSSION: Most prescriptions were adequate. The patient profile could explain the high rate of antibiotic consumption. Bacteriological monitoring revealed an increased prevalence of resistant bacteria, which could explain a high rate of consumption along with adaptation of the dose to overweight. De-escalation, using aminosides more frequently, and shorter prescribed courses of fluoroquinolones should improve consumption rates does not always reflect bad practices, but may be adequate when considering bacterial ecology and patient profile.

[Infections complicating femoral nerve catheter for postoperative analgesia: about two cases]. / Complications infectieuses et cathéter périnerveux fémoral pour l'analgésie postopératoire: à propos de deux cas.

The process of inserting a perineural catheter on femoral region for a regional anesthesia is quite common amongst hospital practices. The resulting infectious complications, although rare, remain potentially serious. For instance, many cases of severe sepsis were described in medical literature. In this paper, we will be presenting two cases of infections that were under serious investigation and led to major improvements of practice in the related hospitals. At the same time, we will give a reminder of good practices in inserting perineural catheters.

[Hospital fluoroquinolone prescription habits in northern France]. / Enquête sur les habitudes de prescription des fluoroquinolones dans la région Nord-Pas de Calais.

OBJECTIVE: The aim of the study was to assess the good use organization and fluoroquinolone prescription habits in cases of bone and joint, urinary, pulmonary, and digestive infections. DESIGN: A declarative survey was made (questionnaire for the hospital and for the prescriber). RESULTS: Thirty percent (44/145) of hospitals participated with 274 prescribers. Eighty percent had prescription protocols, 71 % of clinicians had access to epidemiologic data. A percentage of 30.7 (853/2,771) of prescriptions included a fluoroquinolone, 44.5 % (380/853) among these had not been recommended. The excessive prescription reached 24.4 % (116/474) in case of bone and joint infection, 14.6 % (107/731), and 20 % (157/779) in cases of digestive and respiratory infection respectively. Prescriptions for urinary infection were adequate in 47.6 % (375/787) of cases. Inadequate prescriptions were made because of bad knowledge of bacteria resistance epidemiology and pharmacology (insufficient dose, monotherapy at risk of selection), and non-application of good practice recommendations. CONCLUSION: This study justifies the rationalization of antibiotic prescription.

Evaluation of glycopeptide use in nine French hospitals.

BACKGROUND: Adequate glycopeptide use is necessary to optimize efficacy and minimize adverse events and selection of drug resistant microorganisms. METHODS: We performed a multicenter prospective observational study of glycopeptides indications based on modified HICPAC criteria, and quality of prescription based on French consensus recommendations. We assessed the adequacy of indications, loading dose, maintenance dose, administration frequency, serum monitoring and its consequences. RESULTS: We evaluated 117 curative adult prescriptions from nine hospitals. Glycopeptide indications were adequate in 71% with either a clinical (55%) or microbiological justification (27%). The indication was more frequently adequate for vancomycin than for teicoplanin (77% vs. 60%, p=0.04). De-escalation therapy was performed in 48% of all documented infections and 78% of documented infections with betalactam susceptible strains. We observed high rates of correct maintenance dose (90%), administration frequency (88%), and serum monitoring (74%). Loading doses (43%), adequate serum monitoring timing (43%), correction of dose because of inadequate levels (32%) were less adequate. Overall, only three (3%) treatments were adequate for all evaluated items. CONCLUSION: Glycopeptide indications were adequate. However, the quality of prescription can be improved and should focus on loading doses and serum monitoring.

Infection risk prevention following total knee arthroplasty.

INTRODUCTION: Implant infection is serious; prevention is mandatory, and requires assessment.The present study assessed the incidence of deep surgical-site infection (SSI) at 1 year following total knee arthroplasty (TKA) and adherence to skin preparation, antibiotic prophylaxis,screening and prevention in case of methicillin-resistant S. aureus (MRSA). HYPOTHESIS: Adherence to prevention measures reduces infection risk secondary to TKA. MATERIAL AND METHODS: A prospective study of the incidence of SSI following primary TKA was run from December 1st 2005 to December 31st 2006 in a continuous series of 364 operations in 359 patients, excluding cases of septic or aseptic revision. Each implant was followed up for 12 months. Adherence to practice was assessed by independent observers. Antibiotic prophylaxis was assessed; skin preparation was scored (out of 10); MRSA was systematically screened for, and preventive measures were assessed in positive cases. Median follow-up was 12 months.Patients with less than 11 months' FU were contacted by telephone. Median age was 72 years(range, 45-92 years). Eighty-seven percent of patients had ASA scores of 2; 14% were diabetic,and 42% obese. Mean surgery time was 70 min (range, 30-164 min). Among the implants, 81.5% were cemented. Eighty-six percent of operations had NNIS scores of 0. Infection risk linked to theater environment and teams was under control. RESULTS: Fourteen patients were lost to follow-up and excluded from analysis. The incidence of infection was 1.4% (n = 5/350) (95% CI [0.41-3.22]). Three of the infections were early (