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J L Mainardi

Publications and source records attributed to J L Mainardi.

At least 19 recordsLinked to original sources
PubMed2004

[Retrospective study of bacteremia diagnosed in an emergency department: frequency, susceptibility of microorganisms, and impact on therapeutic management].

OBJECTIVE: The authors had for aim to determine the prevalence of bacteremia diagnosed in an emergency department (ED), the susceptibility of microorganisms to antibiotics, and the impact on therapeutic management. DESIGN: A retrospective analysis was made on patient features, microbiological ecology, susceptibility to antibiotics, and modalities of antimicrobial therapy in the Georges Pompidou European hospital ED of Hôpital, between 1 November 2001 and 30 June 2002. RESULTS: One thousand four hundred and thirty two blood cultures were obtained from 1069 patients. The rate of positive cultures was 12%, but only 8.7% (n = 125) were proved as true bacteremia. The most frequently identified organisms were: Enterobacteriaceae (n = 63, 39.4%) with a predominance of Escherichia coli (n = 48, 30%), and Streptococcus pneumoniae (n = 16, 10%). Forty two cases of pyelonephritis and 34 of prostatitis both due to E. coli were diagnosed. 76.5% of these were resistant to amoxicillin, 64.7% to amoxicillin-clavulanic acid, 11.8% to ciprofloxacin, and 44% to cotrimoxazole. No resistance to third generation cephalosporin was detected in E. coli isolates. Fourteen S. pneumoniae pneumonia cases were diagnosed. 57.1% of isolates presented with a decreased susceptibility to penicillin (CMI > 0.1 mg/l). Susceptibility to amoxicillin and cefotaxim was 85.7% and 92.9% respectively. Blood culture was the only exam available for bacterial diagnosis in 51.5% of true bacteremia. 1.6% of blood cultures from ED samples had an impact on therapeutic management. CONCLUSIONS: Blood culture is a relevant exam for the diagnosis of infection in patients admitted to the ED.

Bacteremia↗
PubMed2003

Molecular diagnosis of a vascular prosthesis infection, due to Propionibacterium acnes, by amplification and sequencing of 16S rDNA.

We describe a case of indolent vascular prosthesis infection due to Propionibacterium acnes. The microorganism was identified only by amplification and sequencing of 16S rDNA, while standard cultures remained negative. This observation underscores the usefulness of molecular techniques for the diagnosis of infection caused by fastidious microorganisms.

Anti-Bacterial Agents↗
PubMed2003

Fulminant invasive pulmonary aspergillosis in immunocompetent patients--a two-case report.

Two cases of invasive aspergillosis (IA) in immunocompetent patients with a fulminant fatal outcome are reported. Both patients were elderly and had a history of chronic lung disease treated with prolonged inhaled corticosteroids and a short course of systemic corticosteroids. They presented with dyspnea and fever, their respiratory function deteriorated rapidly, and they died 7 days after admission. Aspergillus fumigatus was cultured from respiratory samples. IA was confirmed in one case by necropsy that showed diffuse bilateral necrotizing pneumonitis and myocarditis. In the other case, IA diagnosis was established by thoracic CT scan plus detection of Aspergillus antigen in two blood samples. These two cases demonstrate that short-term corticosteroid therapy in immunocompetent patients with underlying chronic lung conditions is a risk factor for IA, and that its evolution can be fulminant.

Administration, Inhalation↗
PubMed2001

Identification of the UDP-MurNAc-pentapeptide:L-alanine ligase for synthesis of branched peptidoglycan precursors in Enterococcus faecalis.

Many species of gram-positive bacteria produce branched peptidoglycan precursors resulting from the transfer of various L-amino acids or glycine from amino acyl-tRNA to the epsilon-amino group of L-lysine. The UDP-MurNAc-pentapeptide:L-alanine ligase and alanyl-tRNA synthetase genes from Enterococcus faecalis were identified, cloned, and overexpressed in Escherichia coli. The purified enzymes were necessary and sufficient for tRNA-dependent addition of L-alanine to UDP-MurNAc-pentapeptide in vitro. The ligase belonged to the Fem family of proteins, which were initially identified genetically as factors essential for methicillin resistance in Staphylococcus aureus.

Alanine↗
PubMed2001

Detection of fastidious bacteria in cardiac valves in cases of blood culture negative endocarditis.

The diagnosis of blood culture negative endocarditis is still a problem. Fastidious bacteria such as bartonella and coxiella are responsible for cases of blood culture negative endocarditis, the identification of which is mainly based on serological and DNA studies only available in specialised centres. Therefore, a routine technique is needed in surgical pathology laboratories to detect these bacteria in cardiac valve tissue sections. This report describes a staining technique, the Gimenez stain, feasible and sensitive in detecting bartonella and coxiella in two cases of blood culture negative endocarditis.

Adult↗
PubMed2001

[Diabetic foot ulcers: anti-infectious strategies].

Infection is a common problem in diabetic patients with foot ulcers. The diagnosis of infection is not always easy to establish, but must be made for proper therapeutic decision making. In addition to local care, search for arteriopathy and strict control of blood glucose, treatment of infected foot ulcers requires an appropriate anti-infectious strategy. We developed diagnostic and therapeutic decisional algorithms from data available in the literature in order to establish a management strategy for different clinical situations. The fundamental role of clinical assessment is underlined and the different causal microorganisms are recalled, together with the anti-microbial activity and bone concentrations of the main antibiotics used. An optimal anti-infection work-up can undoubtedly significantly reduce the number of amputations in diabetic patients.

Algorithms↗
PubMed2000

Novel mechanism of beta-lactam resistance due to bypass of DD-transpeptidation in Enterococcus faecium.

The peptidoglycan structure of in vitro selected ampicillin-resistant mutant Enterococcus faecium D344M512 and of the susceptible parental strain D344S was determined by reverse phase high performance liquid chromatography and mass spectrometry. The muropeptide monomers were almost identical in the two strains. The substantial majority (99.3%) of the oligomers from the susceptible strain D344S contained the usual d-alanyl --> d-asparaginyl (or d-aspartyl)-l-lysyl cross-link (d-Ala --> d-Asx-l-Lys) generated by beta-lactam-sensitive DD-transpeptidation. The remaining oligomers (0.7%) were produced by beta-lactam-insensitive LD-transpeptidation, because they contained l-Lys --> d-Asx-l-Lys cross-links. The muropeptide oligomers of the ampicillin-resistant mutant D344M512 contained only these l-Lys --> d-Asx-l-Lys cross-links indicating that resistance was due to the bypass of the beta-lactam-sensitive DD-transpeptidation reaction. The discovery of this novel resistance mechanism indicates that DD-transpeptidases cannot be considered anymore as the sole essential transpeptidase enzymes.

Amino Acid Sequence↗
PubMed2000

Antienterococcal antibiotics.

The treatment of severe enterococcal infections based on the currently available antibacterial agents is difficult. The help of the microbiology laboratory for determining MICs, MBCs, and most effective synergistic combinations is crucial. There is a need for good prospective multicenter clinical trials to improve the prognosis of such infections by defining therapeutic strategies better. Such a requirement is highly suitable for the treatment of infections caused by enterococci exhibiting acquired resistance mechanisms to the available agents. The current clinical development of new compounds looks promising in these persistently life-threatening infections mostly occurring in deficient hosts.

Anti-Bacterial Agents↗
PubMed2000

A one-year prospective study of nosocomial bacteraemia in ICU and non-ICU patients and its impact on patient outcome.

A one-year, prospective, two-observational cohort study was performed to evaluate the incidence and outcome in hospitalized patients (ICU and non-ICU) of nosocomial bacteraemia, and to assess its prognostic value in the ICU group. A group of 18 098 hospitalized patients and a group of 291 consecutive ICU patients were followed. Prognostic factors were determined using single and multivariable analyses. 109 (90 non-ICU and 19 ICU) patients developed 118 nosocomial bacteraemic episodes. The incidence of nosocomial bacteraemia was 6.0 per 1000 admissions (95% confidence interval (CI): 5-7%) and 65 per 1000 admissions in ICU patients (95% CI: 4.5-8.5%). Gram-positive and Gram-negative bacteria were 63/133 (47%) and 70/133 (53%) of the isolated micro-organisms respectively. Crude mortality rates were 41/109 (38%) with adverse outcome associated with mechanical ventilation (OR: 3.6; 95% CI: 1.4-9.2, P =0.01), neutropenia (OR: 7.7; 95% CI: 0.8-73.1;P =0.07) while gastro-intestinal surgery was associated with an improved outcome (OR: 0.4; 95% CI: 0.16-0.96;P =0.04). Of the 291 ICU patients, 19 acquired 22 episodes of nosocomial bacteraemia, and 18 were referred from the wards with documented nosocomial bacteraemia. Of these 37 bacteraemic patients, 17 (46%) died. When adjusting for predictors of death (SAPS II>/=40, cardiac and neurological failure), nosocomial bacteraemia markedly influence the outcome in ICU patients (OR: 3.4; 95% CI: 1.3-8.7;P =0.010). This study suggests that the outcome of nosocomial bacteraemia in hospitalized patients is poor in ventilated and neutropenic patients and that nosocomial bacteraemia per se influenced outcome in ICU patients.

Aged↗
PubMed2000

Streptococcus pneumoniae endocarditis in adults. A multicenter study in France in the era of penicillin resistance (1991-1998). The Pneumococcal Endocarditis Study Group.

To better define the overall characteristics and risk factors for dying of adult pneumococcal endocarditis (PE) focusing on the echocardiographic diagnosis, the impact of surgery, and emergence of penicillin resistance, the medical and microbiologic charts of adult PE cases observed between 1991 and 1998 in university and general hospitals were reviewed through a nationwide retrospective study in France. Thirty cases of PE (22 men, 8 women; median age, 53 yr; range, 27-87 yr) were collected and validated. Twenty patients (66.7%) had no known predisposing cardiopathy; 4 had a bioprosthetic valve. The primary focus of infection was pneumonia in 10 (33.3%), and meningitis was noted in 12 (40.0%). Half the patients suffered from chronic alcoholism. Echocardiography detected vegetation(s) in 29 cases (96.7%), valvular perforation in 6 (20.0%), and/or valve ring abscess in 4 (13.3%). The most frequent complications were congestive heart failure (n = 19), large arterial emboli (n = 8), and focal abscesses (n = 7). Five strains were penicillin-resistant. Twenty (66.7%) patients underwent valve replacement, 12 of them during the first month. The overall mortality rate was 24.1%. According to a multivariate analysis, the risk factors independently associated with dying were age > or = 65 yr and septic shock, while cardiac surgery was protective (p < 0.01). In conclusion, PE is usually fulminant and causes severe valve damage and embolic complications; its short-term prognosis might be improved by early valve replacement.

Adult↗
PubMed2000

Vancomycin resistance is associated with serine-containing peptidoglycan in Enterococcus gallinarum.

In Enterococcus gallinarum SC1, a low-level vancomycin-resistant strain, only monomeric muropentapeptides with a C-terminal D-alanine were detected after growth without vancomycin. In contrast, in SC1 induced by vancomycin, as well as in AIB39, a constitutive vancomycin-resistant strain, monomeric and dimeric muropentapeptides with a C-terminal D-serine were detected.

Anti-Bacterial Agents↗
PubMed2000

Outbreak of methicillin-resistant Staphylococcus aureus with reduced susceptibility to glycopeptides in a Parisian hospital.

Epidemiological relationships were investigated between 40 methicillin-resistant Staphylococcus aureus (MRSA) strains with decreased glycopeptide susceptibility isolated from November 1998 to March 1999 from 39 patients (17 infected and 22 colonized patients) in nine wards of the Broussais Hospital, Paris, France. Reduced glycopeptide susceptibility was readily detected on brain heart infusion (BHI) agar containing 6 microg of teicoplanin per ml and on gradient plates, but not by the standard disk diffusion method. The MICs of vancomycin and teicoplanin, determined on BHI agar, were 4 and 8 to 32 microg/ml, respectively (standard antibiotic dilution), and 4 to 8 and 8 to 32 microg/ml, respectively (E-test). All strains were resistant to macrolides, aminoglycosides, tetracycline, rifampin, sulfonamides, and pefloxacin, showed reduced susceptibility to fusidic acid and fosfomycin, and were susceptible to trimethoprim and chloramphenicol. Pulsed-field gel electrophoresis and lysotyping revealed that a multidrug-resistant MRSA clone with decreased susceptibility to glycopeptides has been discretely endemic since at least 1996 in our institution, where it was responsible for an outbreak in November and December 1998.

Anti-Bacterial Agents↗