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Background: Escherichia coli is a rare cause of community-acquired meningitis in adults unless predisposing factors are present (e.g., previous penetrating cranio-cerebral injury or neurosurgery, immunosuppression, chronic alcoholism, history of cancer, diabetes mellitus, advanced age).Case Presentation: We describe the case of a 53-year-old woman, resident in Germany, suffering from community-acquired bacterial meningitis caused by CTX-M-9 type extended spectrum β-lactamase producing Escherichia coli. Because typical predisposing factors were not apparent, pathogen identification resulted in expanded diagnostics to exclude a distant or contiguous primary focus. By magnetic resonance tomography, a previously unrecognized large retropharyngeal abscess with cervical spondylodiscitis was detected. In retrospect, the patient had complained about neck pain for a few weeks prior to meningitis onset, but the symptoms were interpreted as being related to a herniated disk. Meningitis and osteomyelitis resolved completely under surgical treatment and meropenem therapy.Conclusion: In case of adult Escherichia coli meningitis, underlying diseases should always be carefully excluded, especially if predisposing factors are not apparent. [ABSTRACT FROM AUTHOR]

We studied the presence of extended spectrum beta lactamases (ESBLs) in 44 clinical isolates of Escherichia coli collected from out-patients in two university teaching hospitals in South-Eastern Nigeria. Species identification was performed by standard microbiology methods and re-confirmed by MALDI-TOF technology. Phenotypic characterization of ESBL enzymes was done by double disc synergy test and presence of ESBL genes was determined by specific PCR followed by sequencing. Transfer of plasmid DNA was carried out by transformation using E. coli DH5 as recipient strain. Phenotypic characterization identified all isolates to be ESBL positive. 77% of strains were from urine, 13.6% from vaginal swabs and 9.0% from wound swabs. 63.6% were from female patients, 68% were from outpatients and 95.5% from patients younger than 30 years. All ESBL producers were positive in a PCR for blaCTX-M-1 cluster, in exemplary strains blaCTX-M-15 was found by sequencing. In all strains ISEcp1 was found upstream and ORF477 downstream of blaCTX-M. PCR for blaTEM and blaOXA-1 was positive in 93.1% of strains, whereas blaSHV was not detected, aac(6')-Ib-cr was found in 97.7% of strains. RAPD analysis revealed seven different clonal groups named A through G with the majority of the strains (65.9%) belonging to clone A. Transfer of an ESBL plasmid with co-resistance to gentamicin, kanamycin, tobramycin, doxycycline and trimethropim-sulfamethoxazolewas successful in 19 (43.2%) strains. This study showed a high rate of CTX-M-1 cluster - ESBLs in South-Eastern Nigeria and further confirms the worldwide spread of CTX-M ESBL in clinical isolates. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus lugdunensis is an important human pathogen that causes potentially fatal endocarditis, osteomyelitis and skin and soft tissue infections similar to diseases caused by Staphylococcus aureus. Nevertheless, in contrast to S. aureus, data on pathogenicity factors of S. lugdunensis is scarce. Two adhesins, a fibrinogen and a von Willebrand factor binding protein, and a S. lugdunensis synergistic hemolysin (SLUSH) have been previously described. Moreover, the newly sequenced genome of S. lugdunensis revealed genes of other putative fibrinogen binding adhesins and hemolysins. The aim of this study was to gain more insight into the occurrence of genes likely coding for fibrinogen binding adhesins and hemolysins using clinical strains of S. lugdunensis. Findings: Most of the putative adhesin genes and hemolysin genes investigated in this study were highly prevalent, except for the SLUSH gene cluster. In contrast to previous reports, binding to fibrinogen was detected in 29.3% of the S. lugdunensis strains. In most strains, hemolysis on blood agar plates was weak after 24 h and distinct after 48 h of incubation. The fibrinogen binding and hemolysis phenotypes were also independent of the type of clinical specimen, from which the isolates were obtained. Conclusion: In this study we described a pyrrolidonyl arylamidase negative S. lugdunensis isolate. Our data indicate that a matrix-assisted laser desorption ionisation time-of-flight MS-based identification of S. lugdunensis or speciesspecific PCR's should be performed in favour of pyrrolidonyl arylamidase testing. In contrast to the high occurrence of putative fibrinogen binding protein genes, 29.3% of the S. lugdunensis strains bound to fibrinogen. Putative hemolysin genes were also prevalent in most of the S. lugdunensis strains, irrespective of their hemolysis activity on Columbia blood agar plates. Similar to a previous report, hemolysis after 48 h of incubation is also indicative for S. lugdunensis. The SLUSH gene cluster was detected in an estimated 50% of the strains, indicating that this locus is different or non-prevalent in many strains. [ABSTRACT FROM AUTHOR]

Background: The main aim of this study was to examine the genotypic and phenotypic diversity of Staphylococcus saprophyticus isolates from human and animal origin. Findings: In total, 236 clinical isolates and 15 animal isolates of S. saprophyticus were characterized in respect of the occurrence of 9 potential virulence genes and four surface properties. All strains were PCR positive for the regulatory genes agr, sar>it>A and rot as well as for the surface proteins UafA and Aas. Nearly 90% of the clinical isolates were found to possess the gene for the surface-associated lipase Ssp and 10% for the collagen binding MSCRAMM SdrI. All animal isolates were negative forsdrI. Lipolytic activity could be detected in 66% of the clinical and 46% of the animal isolates. Adherence to collagen type I was shown of 20% of the clinical strains and 6% of the strains of animal origin. Most S. saprophyticus strains showed hydrophobic properties and only few could agglutinate sheep erythrocytes. Conclusions: We described a broad analysis of animal and human S. saprophyticus isolates regarding virulence genes and phenotypic properties such as lipase activity, hydrophobicity, and adherence. While S. saprophyticus strains from animal sources have prerequisites for colonization of the urinary tract like the D-serine-deaminase, out findings suggested that they need to acquire new genes e.g. MSCRAMMS for adherence like sdrI and to modulate their existing properties e.g. increasing the lipase activity or reducing hydrophobicity. These apparently important new genes or properties for virulence have to be further analyzed. [ABSTRACT FROM AUTHOR]

Background: The Gram-positive bacterium Staphylococcus saprophyticus is the second most frequent causative agent of community-acquired urinary tract infections (UTI), accounting for up to 20% of cases. A common feature of staphylococci is colonisation of the human skin. This involves survival against innate immune defenses including antibacterial unsaturated free fatty acids such as linoleic acid which act by disrupting bacterial cell membranes. Indeed, S. saprophyticus UTI is usually preceded by perineal skin colonisation., Results: In this study we identified a previously undescribed 73.5 kDa cell wall-anchored protein of S. saprophyticus, encoded on plasmid pSSAP2 of strain MS1146, which we termed S. saprophyticus surface protein F (SssF). The sssF gene is highly prevalent in S. saprophyticus clinical isolates and we demonstrate that the SssF protein is expressed at the cell surface. However, unlike all other characterised cell wall-anchored proteins of S. saprophyticus, we were unable to demonstrate a role for SssF in adhesion. SssF shares moderate sequence identity to a surface protein of Staphylococcus aureus (SasF) recently shown to be an important mediator of linoleic acid resistance. Using a heterologous complementation approach in a S. aureus sasF null genetic background, we demonstrate that SssF is associated with resistance to linoleic acid. We also show that S. saprophyticus strains lacking sssF are more sensitive to linoleic acid than those that possess it. Every staphylococcal genome sequenced to date encodes SssF and SasF homologues. Proteins in this family share similar predicted secondary structures consisting almost exclusively of α-helices in a probable coiled-coil formation., Conclusions: Our data indicate that SssF is a newly described and highly prevalent surface-localised protein of S. saprophyticus that contributes to resistance against the antibacterial effects of linoleic acid. SssF is a member of a protein family widely disseminated throughout the staphylococci.