Short duration of post-amputation antibiotic therapy in diabetic foot patients with total resection of osteomyelitis.

BACKGROUND: Short duration of post-amputation antibiotic therapy (2-5 days) is recommended in patients with diabetic foot osteomyelitis after total resection of infected bone tissue. OBJECTIVE: To evaluate the long-term effectiveness of short-duration post-amputation antibiotic therapy in diabetic patients with total resection of osteomyelitis assessed by sterile bone bacteriological samples obtained from the resection margin. METHODS: The endpoint was the absence of osteomyelitis relapse at 6 months, defined as recurrence of osteomyelitis with the need for surgical revision and/or new bone antibiotic therapy. RESULTS: Among 15 patients included, 12 (80%) were cured without recurrence of osteomyelitis at 6 months, with a mean duration of antibiotic therapy of 8.3±5.9 days post surgery. This result is comparable to literature data, while all of them reported longer duration of antibiotic therapy and/or shorter follow-up. CONCLUSION: Short duration of post-amputation antibiotic therapy in diabetic patients with sterile bacteriological samples obtained from resection margin seems effective.

Are systematic drain tip or drainage fluid cultures predictive of surgical site infections?

Systematic cultures of drain tips or drainage fluids for the early detection of surgical site infections (SSIs) are controversial. To examine the association between the results of systematic drain tip or drainage fluid cultures and the occurrence of SSIs in clean or clean-contaminated surgery. Searches were performed in the PubMed, and Cat.inist databases for observational studies published before 31st March 2017. Studies reporting results of drain tip or drainage fluid systematic cultures and SSIs after clean or clean-contaminated surgeries were included, and meta-analyses were performed. Seventeen studies, including 4390 patients for drain tip cultures and 1288 for drainage fluid cultures, were selected. The pooled negative predictive values were high (99%, 95% confidence interval (CI) 98-100 for drain tip cultures and 98%, 95% CI 94-100 for drainage fluid cultures). The positive predictive values were low (11%, 95% CI 2-24 for drain tip cultures and 12%, 95% CI 3-24 for drainage fluid cultures). The sensitivities were low (41%, 95% CI 12-73 for drain tip cultures and 37%, 95% CI 16-60 for drainage fluid cultures). The specificities were high (93%, 95% CI 88-96) for drain tip cultures and moderate (77%, 95% CI 54-94) for drainage fluid cultures. Systematic cultures of drain tips or drainage fluids appear not to be relevant, because their positive predictive values were low in the prediction of SSIs.

Knowledge of antibiotics and antibiotic resistance in patients followed by family physicians.

OBJECTIVE: We aimed to evaluate factors associated with knowledge of antibiotics and drug resistance. METHODS: A questionnaire was handed out by 14 family physicians to their patients between December 20, 2014 and April 20, 2015 in Rethel (North-East of France). We conducted a cross-sectional study using a logistical regression model to assess factors associated with antibiotic knowledge. Three criteria were used to assess that knowledge. RESULTS: Overall, 293 questionnaires were analysed; 48% of patients had received antibiotics in the previous 12 months. Only 44% and 26% gave a correct answer for the statements "Antibiotics are effective against bacteria and ineffective against viruses" and "Antibiotic resistance decreases if the antibiotic use decreases", respectively. Characteristics such as female sex, age>30 years, high level of education, high professional categories, and having received antibiotic information by the media were associated with high level of knowledge about antibiotics and/or antibiotic resistance. In contrast, having received antibiotic information from family physicians was not associated with good knowledge. CONCLUSION: Although media awareness campaigns had an independent impact on a higher public knowledge of antibiotics, the overall public knowledge remains low. It would be necessary to strengthen antibiotic campaigns with clearer information on the relation between the excessive use of antibiotics and the increased risk of antibiotic resistance. Family physicians should be more involved to improve antibiotic knowledge among target groups such as men, young patients, and people from a poor social and cultural background.

Decline in antibiotic resistance and changes in the serotype distribution of Streptococcus pneumoniae isolates from children with acute otitis media; a 2001-2011 survey by the French Pneumococcal Network.

Streptococcus pneumoniae is an important cause of acute otitis media (AOM). The aim of this study was to evaluate trends in antibiotic resistance and circulating serotypes of pneumococci isolated from middle ear fluid of French children with AOM during the period 2001-2011, before and after the introduction of the PCV-7 (2003) and PCV-13 (2010) vaccines. Between 2001 and 2011 the French pneumococcal surveillance network analysed the antibiotic susceptibility of 6683 S. pneumoniae isolated from children with AOM, of which 1569 were serotyped. We observed a significant overall increase in antibiotic susceptibility. Respective resistance (I+R) rates in 2001 and 2011 were 76.9% and 57.3% for penicillin, 43.0% and 29.8% for amoxicillin, and 28.6% and 13.0% for cefotaxime. We also found a marked reduction in vaccine serotypes after PCV-7 implementation, from 63.0% in 2001 to 13.2% in 2011, while the incidence of the additional six serotypes included in PCV-13 increased during the same period, with a particularly high proportion of 19A isolates. The proportion of some non-PCV-13 serotypes also increased between 2001 and 2011, especially 15A and 23A. Before PCV-7 implementation, most (70.8%) penicillin non-susceptible pneumococci belonged to PCV-7 serotypes, whereas in 2011, 56.8% of penicillin non-susceptible pneumococci belonged to serotype 19A. Between 2001 and 2011, antibiotic resistance among pneumococci responsible for AOM in France fell markedly, and PCV-7 serotypes were replaced by non-PCV-7 serotypes, especially 19A. We are continuing to assess the impact of PCV-13, introduced in France in 2010, on pneumococcal serotype circulation and antibiotic resistance.

Gastroscopy-associated transmission of extended-spectrum beta-lactamase-producing Pseudomonas aeruginosa.

An unusual multi-drug-resistant Pseudomonas aeruginosa (MDR-PA) was isolated in four patients whilst hospitalized in a French teaching hospital between May and August 2011. All four patients had undergone an oesophago-gastro-duodenoscopy with the same gastroscope over a five-month period. This endoscope was associated with a culture positive for the MDR-PA. Observations of endoscope reprocessing identified deviations from the agreed processes: insufficient initial cleaning, shortening of the immersion time and brushing time, insufficient channel flushing, and inadequate drying prior to storage. Since withdrawing the gastroscope and institution of strict adherence to the agreed processes, no other MDR-PA cases have been isolated.

[Predictive factors of acquisition of epidemic extended-spectrum beta-lactamase-producing Escherichia coli]. / Etude des facteurs prédictifs d'acquisition d'une souche épidémique d'Escherichia coli productrice de bêta-lactamase à spectre étendu.

The aim of the study was to determine predictive factors of epidemic extended spectrum beta-lactamase-producing Escherichia coli acquisition. All patients presenting any type of culture positive for ESBL-producing E. coli between November 2006 and October 2007 were included. An epidemic case was defined as a patient colonized with a clonal strain having epidemiological link with an another patient harbouring the same strain. Clinical and administrative data were recorded. Groups were compared by univariate and multivariate analysis using SAS software. Were included in this study 148 patients: 60 epidemic and 88 sporadic cases. Multivariate analysis showed several predictive factors of epidemic strain acquisition: female gender, high Charlson index, treatment by amoxicillin or ticarcillin-clavulanic acid, admission to emergency unit and hospitalisation in a high number of different care units. Identification of predictive factors of epidemic ESBL-producing E. coli strains acquisition may help to limit cross transmission of such strains.

[Is it possible to detect Staphylococcus aureus colonization or bacteriuria before orthopedic surgery hospitalization?]. / Le dépistage en ambulatoire des patients porteurs de Staphylococcus aureus ou présentant une colonisation urinaire et devant bénéficier d'une chirurgie orthopédique est-il réaliste ?

AIM OF THE STUDY: Evaluate the feasibility of Staphylococcus aureus nasal colonization and bacteriuria screening in outpatients before realizing a decolonization treatment in S. aureus carriers and a bacteriuria treatment before hospitalization. METHODS: All patients undergoing hip, knee or back surgery in which prosthesis were implanted between October 2007 until the end of June 2008 were included. Microbiological studies were performed before hospitalization. Notice for S. aureus decolonization regimen was delivered to each patient and to the general practitioner only if the patient had nasal carriage. RESULTS: Only 91.2% (240/263) of patients had microbiological results. Prevalence of S. aureus colonization was 21.4% (48 positives/224). Three patients were colonized with methicillin-resistant staphylococci. Decolonization regimen was applied before surgery to 70.8% (n=34) of the colonized patients. Among the patients, 8.9% (20/225) had bacteriuria, Escherichia coli being the most frequent micro-organism (n=16). CONCLUSION: Preoperative search and management of S. aureus colonization and of bacteriuria in outpatients is possible. Monitoring record must be performed by a member of the hospital staff.

[Real-time PCR for fast detection of plasmid-mediated qnr genes in extended spectrum beta-lactamase producing Enterobacteriaceae]. / Mise au point d'une technique de PCR en temps réel pour la détection rapide des gènes qnr chez des entérobactéries productrices de bêta-lactamases à spectre étendu.

AIM OF THE STUDY: To develop a fast and reliable real time PCR technique for detecting plasmid-mediated quinolone resistance genes qnrA, qnrB and qnrS. METHODS: A real-time PCR assay using SYBR Green I and Roche LightCycler(®) was developed to detect qnr genes. Detection of qnr genes was based on comparison of melting temperature differences with a positive control of each qnr genes. This assay was performed to study 138 isolates collected from diagnostic and screening samples in the Champagne-Ardenne region in 2004 (France). RESULTS: In optimized conditions, the three positive controls tested alone and with isolates confirmed the specificity of the PCR primers. Each PCR assay was able to test 30 strains in 60min for 1 qnr gene. Out of 138 isolates screened, 3.6 % isolates were positive for a qnrA1, 1.5 % for qnrS1 and no qnrB-like gene. Prevalence of qnr determinants was 5 % and reached 9.5 % in clinical isolates. CONCLUSION: Real-time PCR is a fast and reliable technique for screening of qnr-positive strains. This study shows a relatively high prevalence of qnr determinants (5 %) among ESBL-producing Enterobacteriaceae.

Incidence of class A extended-spectrum beta-lactamases in Champagne-Ardenne (France): a 1 year prospective study.

OBJECTIVES: To assess the frequency and diversity of extended spectrum beta-lactamases (ESBLs) in the Champagne-Ardenne region France, and to identify genetic elements associated with the bla(CTX-M) genes. METHODS: During 2004, all the non-duplicate isolates of Pseudomonas aeruginosa and Acinetobacter baumannii resistant to ceftazidime and of Enterobacteriaceae intermediate or resistant to ceftazidime and/or cefotaxime, screening samples excluded, were collected in 10 public hospitals and 3 private clinics. bla genes were sequenced and bla(CTX-M) environment characterized by PCR mapping. RESULTS: In Enterobacteriaceae (138/21 861; 0.6%), ESBLs were predominantly TEM-24 (n = 52; 37.7%) and CTX-M-15 (n = 37; 26.8%). Three new enzymes were identified, CTX-M-61 (CTX-M-1 group), TEM- and SHV-type. A. baumannii (n = 5) produced VEB-1 and P. aeruginosa (n = 2) SHV-2a. ISEcp1 was detected in 22/27 strains, disrupted in 7 of them. The IS903-like element was downstream of bla(CTX-M-14) and bla(CTX-M-16). ISCR1 was found upstream of bla(CTX-M-2) and bla(CTX-M-9), and ISCR1 and bla(CTX-M-2) were located on a sul1-type class 1 integron. In comparison with 2001-02, ESBL distribution among Enterobacteriaceae showed an increase in CTX-M-type (44.9% vs 3.7% P < 10(-7)) due to Escherichia coli CTX-M-15 and to the almost total disappearance of TEM-3 (0.9% vs 51.2%). E. coli was the most frequent species (50.0% vs 5.1% in 1998) despite a similar prevalence to that in 1998 (0.5% vs 0.2%). CONCLUSIONS: A careful detection of bla(CTX-M)-type spread to other species would help to anticipate clonal endemics such as those observed in Enterobacter aerogenes TEM-24.

[Pharmacodynamic interest of ceftazidime continuous infusion vs intermittent bolus administration in patients with severe nosocomial pneumonia]. / Intérêt pharmacodynamique de la perfusion continue vs l'administration intermittente de ceftazidime dans les pneumonies nosocomiales sévères.

GOAL OF THE STUDY: It is well known today that the main determinant of beta-lactam antibiotics efficacy is the duration of the time that concentrations remain in excess of the minimum inhibitory concentration (MIC) of susceptible organism over the course of therapy. This prospective study aimed to evaluate the efficacy, in term of pharmacodynamic profile, of continuous infusion versus intermittent administration of ceftazidime in intensive care unit patients with severe nosocomial pneumonia. PATIENTS AND METHODS: 16 patients under mechanical ventilation with nosocomial pneumonia were randomised to receive either 60 mg/kg/day ceftazidime by constant rate infusion following a 20 mg/kg loading dose (Group A) or 20 mg/kg every 8 hour by intravenous bolus injection (Group B). In both groups, serial blood samples were collected during 48 hours (12 and 18 samples in Group A and B, respectively) after the start of drug administration. Plasma concentrations of ceftazidime were measured by high performance liquid chromatography. Based on our local bacteriological conditions, the pharmacodynamic profile of ceftazidime was assessed as the duration of time the plasma concentration remained above a desired target concentration of 20 mg/l for each regimen. RESULTS: The mean time (expressed as a percentage) for which plasma ceftazidime concentrations were above 20 mg/l was 100% for the continuous infusion group (Group A) and 56+/-33% for the intermittent administration group (Group B). CONCLUSION: These findings show that ceftazidime administered by continuous infusion in critically ill patients under mechanical ventilation with nosocomial pneumonia appears to substantially improve the pharmacodynamic profile of this beta-lactam compared to the intermittent regimen.

[Current role of coagulase-negative staphylococci in urology]. / Place actuelle des staphylocoques à coagulase négative en urologie.

Coagulase-negative Staphylococci (CNS), considered for many years to be commensal bacteria of the skin are now recognized as major agents of nosocomial infection. Bacterial factors (increased resistance), host factors (immune status) and multiplication of the portals of entry (presence of foreign material) have contributed to the increased incidence of nosocomial infections. The importance of the role of NCS in urology is due to their great capacity to colonize catheters and most prostheses. The particular organization of these bacteria into a conglomerate called biofilm is responsible for prosthetic infections, which can impair renal function and can sometimes be life-threatening. The authors review the current increase of the number of CNS isolated in urology departments and describe the various therapeutic strategies that can be proposed to eradicate these bacteria.

[Infection on foreign material: bacterial colonization of ureteral endoprostheses]. / Infection sur matériel étranger: colonisation bactérienne des endoprothèses urétérales.

Infection on foreign body: bacterial colonization of ureteric stents. The most frequent cause of the early removal of ureteric endoprostheses (double J) is generally due to bacterial colonization. In order to prevent or to restrict the prosthesis colonization, it is necessary to understand the major steps and the factors influencing the colonization. This is the reason why we aimed to extract the most relevant parameters influencing the bacterial colonization from the observations made in vivo thanks to in vitro analyses. We have studied in vivo the relationship between the bacterial colonization of the endoprostheses, the urinary infections and the antibiotherapy. In vitro, we have defined the conditions promoting the primary adhesion of the most frequently isolated bacteria on endoprostheses. Surface properties of bacteria and materials have been compared to:--the bacterial count of infected double J samples with respect to bacterial species,--the bacterial count of the infected samples with respect to pH and Ca2+, Mg2+ concentration. The results show a great variability of the biomaterial surface properties which could be optimized, the fact that the urinary medium acidification could lower the bacterial adhesion and the ambiguous role of Ca2+ and Mg2+ ions which is discussed in this paper. In the case of in vivo analyses, the conflicting results between leukocyturia and bacteriuria lead to the detection of the bacterial colonization under antibiotic treatment. The characterized urinary infection must warn the risk of pyelonephritis.

[In vivo and in vitro analysis of the ability of urinary catheter to microbial colonization]. / Analyse in vivo et in vitro de l'aptitude á la colonisation microbienne des sondes urinaires.

Bacterial adhesion to biomaterials is a complex phenomenon involving numerous factors. The ability to reduce urinary catheters infections simply by general hygiene and asepsis is low: an ascending colonization cannot be avoided. This will lead to a clinical infection only if several factors favour the bacterial adhesion or the bacterial coaggregation and the feeding of the bacterial biofilm. Among the many factors involved in bacterial adhesion, we focused in this paper on the physical parameters of surface hydrophobicity of the urinary catheters (Van der Waals and acido-basic forces) and the surface hydrophobicity of the bacteria (BATH and zeta potential). We also compared scanning electron microscopy (SEM) of in vivo and in vitro infected urinary catheters. We provided evidence that the more hydrophobic the bacteria, the more they are able to colonize hydrophobic materials, whereas hydrophilic cells are able to colonize hydrophilic materials more easily. Some biomaterials were found to display an irregular texture of hydrophobic and hydrophilic areas: they favour both types of adhesion. Moreover the divalent cations (MgII) drastically increased the bacterial coaggregation and favour bacterial growth within the biofilm. Finally, an increase in urinary pH and ionic strength increases the colonization risk. Consequently, choice of urinary catheter biomaterials is essential as patient hygiene and diet in order to avoid clinical infections.