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B Pangon

Publications and source records attributed to B Pangon.

At least 19 recordsLinked to original sources
PubMed2006

[Epidemiology of candidemia: results of a one month French hospitals-based surveillance study in 2004].

INTRODUCTION: The aim of our study was to determinate the frequency of candidemia, the species encountered and their susceptibility to antifungal agents in French hospitals in 2004. METHODS: A prospective survey of septicaemia, including candidaemia was conducted among 193 non teaching French hospitals during October 2004. All bloodstream infections were reported and the bloodstream isolates sent to two coordinating centers. Species identification and susceptibility were performed by biologists as usual, and further confirmed by use of alternative methods, including Minimal Inhibitory Concentration (MIC) determination. RESULTS: The survey was effective in 93 hospitals, where 2013 bloodstream infections were noticed, including 46 candidaemia (2.3%). Candida sp. Is the 7th pathogen responsible for bloodstream infection, without concern of the origin of the infection. Candidaemia was hospital acquired in 80.4% of cases (N=37/46). Candidaemia represents 0.7% (N=9/1211) of community-acquired bloodstream infections but 4.5% (N=37/802) of nosocomial cases, placing Candida sp. at the 5th row of frequency in this last group. No mistakes were noticed during identification, but two strains were not named. After confirmation of identification, species are distributed as follows: 23 C.albicans (50%), 13 C.glabrata (28.3%), 5 C.tropicalis (10.9%), 3 C.parapsilosis (6.5%), 1 C.krusei (2.2%), and 1 C.kefyr (2.2%). The overall susceptibility is 97.7% for amphotericin B, 93.2% for 5-fluorocytosin, 88.6% for fluconazole, 70.5% for itraconazole, 95.5% for voriconzole and 100% of strains had very low MIC for caspofungin. Concerning the two main species isolated, 95.5% of C.albicans strains remain susceptible to fluconazole, but only 69% of C.glabrata strains. Two strains, 1 C.albicans and 1 C.glabrata exhibit cross resistance to azoles. The majority of amphotericin, fluconazole, and itraconazole decreased susceptibility strains are found into C.glabrata strains, but susceptibility to 5-fluorocytosin and very low MCI to caspofungin remained in this species. CONCLUSION: Our survey allowed us to get data from French non-teaching hospitals in 2004 about frequency of candidaemia among septicaemia. Candida species distribution and in vitro susceptibility patterns of the strains isolated. Candidaemia is not a rare event, specially when septicaemia is nosocomially acquired. C.albicans is the main species isolated and remains highly in vitro susceptible to antifungals. One important feature is the frequency of C.glabrata in our survey. Considering its decreased susceptibility to azoles, this finding confirms the need for rapid identification of yeast isolated from bloodstream samples, and antifungal susceptibility testing each time it is available.

Antifungal Agents↗
PubMed2003

Frequency of isolation and antimicrobial susceptibility of bacterial pathogens isolated from patients with bloodstream infections: a French prospective national survey.

All bloodstream strains, total 1463, isolated during a 1 month period in 105 hospitals representing all geographical areas in France were collected to study their antimicrobial susceptibility. The three major species were Escherichia coli, Staphylococcus aureus and coagulase-negative staphylococci. Among the 242 S. aureus, 87 were resistant to methicillin and among those 99% were resistant to ciprofloxacin, 11.5% to gentamicin, 1% to quinupristin/dalfopristin and 8% were heterogeneously resistant to vancomycin. Study of the methicillin-resistant S. aureus indicated that 12 clones had disseminated in French hospitals, six being heterogeneously resistant to vancomycin. Among the Streptococcus pneumoniae, 43% showed decreased susceptibility to the penicillins and 42% to erythromycin. One isolate was highly resistant to fluoroquinolones. Gentamicin, cefotaxime, ciprofloxacin and gatifloxacin resistance was rare in Enterobacteriaceae with 95% of strains susceptible. The incidence of extended-spectrum beta-lactamases was quite low. Moreover more than 25% of Pseudomonas aeruginosa strains were resistant to ciprofloxacin and gentamicin. The magnitude of antibiotic resistance in bloodstream isolates, in particular Gram-positive bacteria, emphasizes the importance of hospital control measures, rational prescribing policies and new vaccine strategies.

Anti-Infective Agents↗
PubMed2003

[Acute pyelonephritis: bacteriological data and general course of germ resistance].

Recent bacteriological data concerning pyelonephritis mainly focus on sensitivity to antibiotics and virulence factors. Epidemiologically, and regardless of age and sex of the patients, E. coli remains the most often isolated pathogen. Only 55% of E. coli strains (43% if isolated during a nosocomial infection) are sensitive to amoxicillin. Resistance to parenterally administered third generation cephalosporins remain exceptional. Fluoroquinolones remain very active, particularly in community-acquired infections (>95% sensitive strains). P. aeruginosa, S. aureus and enterococci are mainly isolated during nosocomial infections or in patients with a history of previous hospital admissions. Adhesion factors to urothelial cells are of uppermost importance in the pathogenesis of urinary infection. Adhesins G borne by fimbriae P are mainly concerned. Also, hemolysin is very often present in strains responsible for pyelonephritis. As to the search for these factors in the diagnosis of pyelonephritis, particularly in children, further studies are needed. The choice of antibiotherapy not only rests upon antibiogram data, but also upon pharmacological characteristics of the antibiotic.

Acute Disease↗
PubMed2002

Surveillance of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE) in Northern France: a five-year multicentre incidence study.

In order to measure the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and of Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE), and to evaluate the impact of the national guidelines for multidrug-resistant bacteria (MDRB) prevention in hospitals of Northern France, a multicentre study was conducted for three months every year starting in 1996, in volunteer hospital laboratories. All clinical specimens positive for MRSA and ESBLE were prospectively surveyed. During the five-year surveillance period, the overall proportion of MRSA was 38.4% in the 28,534 strains of S. aureus, and that of ESBLE was 11.4% in the 6121 strains of Klebsiella pneumoniae and 47.7% in the 2353 strains of Enterobacter aerogenes. The overall incidence rates of clinical specimens positive for MRSA, ESBL-K. pneumoniae and E. aerogenes were 0.84. 0.05 and 0.12/1000 hospital-days (HD), respectively. In the 23 hospitals that participated in the survey every year, the proportion and incidence of ESBLE decreased. Hence, despite recommendations as for isolation precautions, MRSA remains poorly controlled and requires more effective measures.

Anti-Bacterial Agents↗
PubMed2000

[Antibiotic sensitivity of enterobacteria in intensive care units].

Antibiotic therapy of intensive care patients is usually undocumented. The treatment is chosen according to epidemiologic and susceptibility data from microbiological laboratories. The aim of our study is to determine antibiotic susceptibility of enterobacteria isolated from intensive care patients during a five-month multicenter study in 18 French hospitals. Numerous (n = 1,113) strains were studied: 447 enterobacteria isolated from urine (n = 229), blood cultures (n = 106), respiratory tract specimens (n = 72), peritoneal fluids (n = 22), pus (n = 15) and catheters (n = 2). MICs of group 2 and group 3 enterobacteria were determined using the dilution agar method and were interpreted according to the CASFM (Comité de l'antibiogramme de la société française de microbiology) recommendations. Group 1 enterobacteria were most frequently isolated (67%). Only one Escherichia coli strain produced ESBL (0.3%). Among group 2 enterobacteria, one Citrobacter koseri strain produced ESBL. We did not isolate Klebsiella pneumoniae ESBL. Isolation of group 3 enterobacteria was frequent (24%). Thirty-five percent of group 3 enterobacteria were resistant to cefotaxime, 26% to ceftazidime and 16% to cefepime and cefpirome. Fourteen strains of this group produced ESBL: 13 Enterobacter aerogenes and one E. amnigenus.

Ascitic Fluid↗
PubMed2000

In vitro activity of teicoplanin against gram-positive cocci.

The glycopeptide susceptibility of 443 clinical isolates of gram-positive cocci collected from nine general hospitals in 1996 was determined according to the recommendations of the CA-SFM (the Antibiogram Committee of the French Society for Microbiology). In total, 234 isolates of Staphylococcus aureus, 84 isolates of coagulase-negative staphylococci (CNS), 98 enterococci and 27 streptococci were collected. The mecA gene confirming resistance to methicillin was found in 42.7% of S. aureus isolates and 51.2% of CNS isolates. No resistance to teicoplanin and vancomycin was found in S. aureus but four isolates of CNS had an MIC of teicoplanin > or = 8 mg/L. All isolates of Enterococcus faecalis tested were susceptible to both glycopeptides. This study confirms that teicoplanin has a very good in vitro activity against gram-positive cocci, isolated in France from nosocomial infections.

Anti-Bacterial Agents↗
PubMed1999

[Mycoplasma pneumoniae pneumopathy. 10 cases].

OBJECTIVES: Describe the different features of a common disease: Mycoplasma pneumoniae pneumonia. PATIENTS AND METHODS: The hospital files of 10 consecutive patients with microbiologically proven Mycoplasma pneumoniae pneumonia were reviewed retrospectively. These 10 patients were hospitalized over a 15-month period among 150 patients admitted to the Versailles general hospital for community-acquired pneumonia. We compared our series with data in the literature. RESULTS: Most of the patients with Mycoplasma pneumoniae pneumonia were young apparently healthy adults. A bronchial risk factor (smoking, allergy) was however found in 60% of the patients. The principle symptom was persistent cough (100%), with fever and joint pain, or sometimes headache and signs of ENT involvement. Dyspnea was frequent, related more to associated bronchospasticity than to the severity of the pneumonia. Radiographic findings were quite variable. In one case hemolytic anemia and cold agglutinins suggested the diagnosis. Certain diagnosis was based on positive serology after hospitalization due to the long delay between symptom onset and hospitalization. The prehospital period was characterized by a succession of ineffective empirical antibiotic regimens. In routine practice, macrolides or fluoroquinolones administered for 2 to 3 weeks are the empirical antibiotics of choice. Outcome is generally favorable with rapid clinical and radiological improvement. Antibiotic therapy is not however sufficient alone to achieve improvement in the respiratory impairment: bronchodilators and corticosteroids are necessary to treat the bronchospasticity. CONCLUSION: Despite the benign nature of community-acquired pneumonia due to Mycoplasma pneumoniae, clinical manifestations, particularly bronchial inflammation may have important consequences.

Adrenal Cortex Hormones↗
PubMed1999

Epidemiological study of Staphylococcus aureus resistant to methicillin responsible for nosocomial infections in nine French hospitals.

A number of European studies found that nosocomial infections were caused by a limited number of methicillin-resistant Staphylococcus aureus (MRSA) strains. A study was undertaken to determine the number of MRSA clones responsible for nosocomial infections in France. Strains responsible for nosocomial infections meeting CDC criteria were collected one week every month from June to October 1997 in nine French hospitals. Strains that were positive by the oxacillin-resistance screening test were studied for the IS 431, femA, and mecA genes. Strain type was identified using pulsed-field gel electrophoresis of fragments produced by Smal digestion. Susceptibility to antimicrobials was evaluated based on inhibition zone diameters and minimal inhibitory concentrations determined using the agar dilution method. The 83 strains studied were distributed across four pulsotypes. Eleven resistance phenotypes were identified by ascending hierarchical classification based on inhibition zone diameters. MRSAs responsible for nosocomial infections belong to a limited number of clones that express variable levels of resistance to antimicrobials.

Anti-Bacterial Agents↗
PubMed1998

Management of acute otitis media caused by resistant pneumococci in infants.

OBJECTIVES: To assess the clinical outcome and risk of failure after oral vs. intravenous treatment in otitis media caused by penicillin-resistant pneumococci. To determine the possible correlations between pneumococcal minimal inhibitory concentration (MIC) to penicillin and clinical outcome. DESIGN: Retrospective study of 156 cases collected between 1993 and 1995. Mean follow-up: 5 months. Setting. Two tertiary academic medical centers in Paris, France. PATIENTS AND METHODS: Pneumococcus was isolated from 191 of 570 ear samples obtained from children with otitis media and shown to be penicillin-resistant in 156. Medical history, antibiotic therapy during the previous 3 months and day-care center attendance were reviewed. For the current episode microbiologic characteristics of the isolated strains, type of treatment, therapy efficacy and clinical outcome were analyzed. Patients were predominantly young (76.3% were <1 year old) and bacteriologic samples were taken mainly because of previous treatment failure. RESULTS: Among 156 children with pneumococcal penicillin-resistant otitis media, 72.2% attended day-care centers, 71.8% had been previously treated with aminopenicillin and 52.5% with cephalosporins. Failure of previous empirical oral therapy was noted in 84% (one-third of these had been receiving amoxicillin-clavulanate). Patients treated intravenously had had a more protracted otitis but no greater number of previous episodes of acute otitis media than those receiving oral therapy. Acute mastoiditis occurred in 4 infants resulting in mastoidectomy. Oral treatment (mainly with high dose amoxicillin,120 to 150 mg/kg/day) and intravenous therapy (cephalosporin or glycopeptide) had been used in 59 and 41%, respectively. Mean duration of therapy was 10.7 days. Three failures (1.9%) and 10 recurrences (6.4%, average 28 days) occurred. No statistical difference was found between intravenous and oral therapy with respect to risk of recurrence. A high penicillin MIC value was correlated with previous antibiotic treatment but not with clinical outcome. CONCLUSIONS: Oral therapy appears to be as effective as intravenous therapy for the treatment of penicillin-resistant pneumococcal otitis media. Intravenous treatment should not necessarily be dictated by the penicillin susceptibility value but should be considered in cases of failure to thrive, persistent otitis or other complications.

Acute Disease↗
PubMed1998

Molecular fingerprinting of Mycobacterium tuberculosis and risk factors for tuberculosis transmission in Paris, France, and surrounding area.

Forty-three percent of the tuberculosis cases reported in France are from the Ile de France region. The incidence of tuberculosis in this region is 33 cases per 100,000 inhabitants, twice the national average. A restriction fragment length polymorphism (RFLP) analysis was performed with clinical isolates of Mycobacterium tuberculosis isolated during 1995 in 10 hospitals in Paris and surrounding areas to detect tuberculosis transmission and define the factors associated with clustering in this population. The molecular markers used were the insertion sequence IS6110 and the direct repeat (DR) sequence. Social, demographic, and clinical data were collected from the patients' medical files. Ten patients with isolates with a single copy of IS6110 were excluded from further analysis. Twenty-four patients with false-positive cultures due to laboratory contamination (based on RFLP analysis with IS6110 and examination of patient data) were also excluded. The study was then conducted with 272 strains isolated from 272 patients. Further fingerprinting was performed by using the DR element with strains with patterns by RFLP analysis with IS6110 that differed by one band only and strains with identical patterns by RFLP analysis with IS6110 and with low numbers of copies of IS6110. The combined use of both markers identified unique patterns for 177 strains and clustered 95 (35.7%) strains in 26 groups, each containing isolates from 2 to 12 patients. The clustering was strongly associated with homelessness and the male sex. It was not associated with age, birth in a foreign country, human immunodeficiency virus positivity, or residence in hostels or prison. Isolates from homeless people were often included in large clusters, and homeless people could be the source of tuberculosis transmission for more than 50% of the clustered patients. These results suggest that homeless people play a key role in the spread of M. tuberculosis in the community and that poor socioeconomic conditions are the main risk factors associated with active tuberculosis transmission.

AIDS-Related Opportunistic Infections↗
PubMed1993

Pharmacokinetics and bactericidal activities of one 800-milligram dose versus two 400-milligram doses of intravenously administered pefloxacin in healthy volunteers.

Pefloxacin pharmacokinetics and serum bactericidal activities (SBA) against Escherichia coli and Staphylococcus aureus were compared after intravenous infusion of either a single 800-mg dose or twice-daily 400-mg doses into 16 healthy volunteers. Plasma pefloxacin concentrations were measured for up to 60 h, and SBAs were determined 1, 12, and 24 h after the start of the infusion. The mean areas under the concentration-versus-time curve for plasma were not different (138 versus 136 h.mg/liter). The mean clearances, volumes of distribution, and half-lives were also comparable. The mean (+/- standard deviation) maximal concentration after the 800-mg infusion was 12.11 +/- 1.35 versus 6.51 +/- 0.73 mg/liter after the first 400-mg infusion and 7.42 +/- 0.76 mg/liter after the second 400-mg infusion. Mean trough concentrations at 24 h were significantly different: 2.77 +/- 0.63 (800 mg) versus 1.93 +/- 0.49 (400 mg twice) mg/liter (P = 0.0007). Mean SBAs against E. coli after 800 mg of pefloxacin were higher than 1/128 (1 h), 1/32 (12 h), and 1/16 (24 h). Mean SBAs against S. aureus under the same conditions were higher than 1/64 (1 h), 1/16 (12 h), and 1/8 (24 h). Mean SBAs at 1 and 12 h were significantly higher after the 800-mg infusion than after the 400-mg infusion but were similar at 24 h for both regimens. Comparison of SBAs according to National Committee for Clinical Laboratory Standards criteria showed a similar adequacy at 24 h for both regimens against both strains. Administration of 800 mg of pefloxacin once a day is bioequivalent to 400 mg twice a day, and bactericidal activity of the 800-mg infusion is not less than that of two 400-mg infusions.

Adult↗
PubMed1991

Single daily dosing of antibiotics: importance of in vitro killing rate, serum half-life, and protein binding.

The relative importance of pharmacokinetic and pharmacodynamic parameters for the feasibility of a single daily dose (SDD) of antibiotics remains to be established. Therefore, we studied the relationship between in vitro bacteriological parameters (MIC, MBC, and killing rate [KR], defined as the reduction in the inoculum within 3 h), pharmacokinetic parameters (t1/2 and protein binding [PB], and in vivo antibacterial effect of a single antibiotic dose in an experimental rabbit model of Escherichia coli endocarditis. Nine antibiotics were investigated: two aminoglycosides, two quinolones, and five beta-lactams. For each drug, the minimal effective dose (MED) (in milligrams per kilogram) was defined as the lowest dose able to achieve a significant difference (P less than 0.05) of CFU in the vegetations in comparison with controls 24 h after a single intravenous injection. Aminoglycosides and quinolones had the lowest MEDs, followed by beta-lactams. Univariate regression analysis showed that KR was the major determinant of MED. A stepwise regression analysis showed that t1/2 significantly improved the predictive value of KR, while PB, MIC, and MBC did not. The final equation was MED = 1,586-238 KR-297 t1/2 (r = 0.90, P = 0.01). We concluded that the pharmacodynamic parameters (especially the high KR) of aminoglycosides and quinolones explained their low MEDs and might allow SDD. In contrast, the low KR of beta-lactams emphasized the critical importance of a long t1/2, as for ceftriaxone, allowing the use of this beta-lactam alone in SDD.

Animals↗
PubMed1990

Ceftriaxone-sulbactam combination in rabbit endocarditis caused by a strain of Klebsiella pneumoniae producing extended-broad-spectrum TEM-3 beta-lactamase.

We studied the activity of the combination of sulbactam and ceftriaxone against a Klebsiella pneumoniae strain producing TEM-3, a new extended-broad-spectrum beta-lactamase, in an endocarditis model. In vitro, ceftriaxone was strongly inactivated in the presence of TEM-3 (MBC, 128 micrograms/ml with an inoculum of 5 x 10(5) CFU/ml). A marked inoculum effect was demonstrated with sulbactam: effective concentrations of inhibitor needed to reduce the MIC and MBC of ceftriaxone to similar levels increased from 1 microgram/ml in the presence of an inoculum of 5 x 10(5) CFU/ml to 20 micrograms/ml in the presence of an inoculum of 1 x 10(7) CFU/ml. In vivo, sulbactam given at 200 mg/kg of body weight every 12 h, a dosage higher than that previously reported to be effective against rabbit endocarditis caused by other microorganisms, was not sufficient to restore the complete activity of ceftriaxone given at 30 mg/kg once daily for 4 days. This insufficient activity may be correlated with the presence of a high level of beta-lactamase inside the vegetations, as indicated by a quantitative in vitro assay of beta-lactamase activity in the cardiac vegetation, suggesting an insufficient inactivation of the extended-broad-spectrum beta-lactamase in vivo.

Animals↗
PubMed1990

Activity of sulbactam in combination with ceftriaxone in vitro and in experimental endocarditis caused by Escherichia coli producing SHV-2-like beta-lactamase.

We studied the efficacy of sulbactam, a beta-lactamase inhibitor, in combination with ceftriaxone in vitro and in experimental endocarditis due to an Escherichia coli strain producing an extended-spectrum beta-lactamase most similar to SHV-2, a new mechanism of resistance to broad-spectrum cephalosporins among members of the family Enterobacteriaceae. In vitro, ceftriaxone demonstrated an important inoculum effect (MICs were 2 and 256 micrograms/ml with 5 X 10(5) and 5 X 10(7) CFU of inoculum per ml, respectively). Sulbactam inhibited the beta-lactamase degradation of ceftriaxone and enhanced the killing by ceftriaxone with both inocula tested. In vivo, sulbactam (100 mg/kg every 8 h) or ceftriaxone (15 or 30 mg/kg every 24 h) alone were ineffective after a 4-day therapy. The addition of sulbactam to ceftriaxone (15 mg/kg) or to the ceftriaxone (15 mg/kg)-netilmicin (6 mg/kg every 24 h) combination produced a reduction of 2 log10 CFU/g of vegetation greater than that produced by therapy without sulbactam. The sulbactam-ceftriaxone (30 mg/kg) combination produced a reduction of almost 5 log10 CFU/g of vegetation greater than that produced by single-drug therapy (P less than 0.01), sterilized five of eight vegetations (versus none of seven for ceftriaxone [30 mg/kg] alone; P less than 0.05), and was as effective as the ceftriaxone (15 mg/kg)-sulbactam-netilmicin combination. We concluded that (i) SHV-2 production was responsible for ceftriaxone failure in vivo, probably because of the high inoculum present in vegetations; (ii) sulbactam used in a regimen which provided levels in serum constantly above 4 micrograms/ml and a vegetation/serum peak ratio of approximately 1:3 enhanced the activity of a broad-spectrum cephalosporin in a severe experimental infection; and (iii) the highest dose of ceftriaxone in combination with sulbactam was as effective as the lowest dose of ceftriaxone plus sulbactam plus an aminoglycoside.

Animals↗