Partial atlE sequencing of Staphylococcus epidermidis strains from prosthetic joint infections.

Partial atlE sequencing (atlE nucleotides 2782 to 3114 [atlE(2782-3114)]) was performed in 41 Staphylococcus epidermidis isolates from prosthetic joint infections (PJIs) and 44 isolates from skin as controls. The atlE(2782-3114) allele 1 (type strain sequence) was significantly more frequent in PJI strains (38/41 versus 29/44 in controls; P = 0.0023). Most PJI strains were positive for mecA, icaA/icaD, and IS256, and most belonged to the sequence type 27 subgroup, suggesting the involvement of few related clones.

Polymorphism of the cell wall-anchoring domain of the autolysin-adhesin AtlE and its relationship to sequence type, as revealed by multilocus sequence typing of invasive and commensal Staphylococcus epidermidis strains.

We sequenced the adhesin-cell wall-anchoring domain of the atlE gene of 49 invasive and commensal Staphylococcus epidermidis strains. We identified 22 alleles, which could be separated into two main groups: group 1 (alleles 1 and 6 to 16, 32/49 strains) and group 2 (alleles 2 to 5 and 17 to 22, 17/49 strains). Allele 1 (the type strain sequence) was by far the most prevalent (21 of 49 strains). Multilocus sequence typing showed a clear relationship between the atlE allele and the sequence type (ST), with the "nosocomial" ST27 clone and closely related STs expressing group 1 alleles.

[Prevalence and characteristics of Guillain-Barré syndromes associated with Campylobacter jejuni and cytomegalovirus in greater Paris]. / Prévalence et caractéristiques des syndromes de Guillain-Barré associés à Campylobacter jejuni et au cytomégalovirus en région parisienne.

AIM OF THE STUDY: We aimed to study prevalence and features of Campylobacter jejuni and cytomegalovirus (CMV)-associated Guillain-Barré syndromes (GBS) in a French care unit. PATIENTS AND METHODS: We studied 264 patients with GBS admitted at Raymond Poincaré hospital (Garches) between 1996 and 2001. Clinical data were obtained prospectively. Sera were collected at patients entry and tested retrospectively for anti-C. jejuni, anti-CMV and antigangliosides GM1 et GM2 antibodies. RESULTS: GBS associated with a serological evidence for a recent C. jejuni infection were the more frequent (58/264, 22%); they affected predominantly men of mature years (mean age: 51.3 years; sex-ratio M/F: 1.76), mostly after a gastrointestinal illness (52%); they were often pure motor forms (57%), were severe (mechanical ventilation: 40%) and associated to an anti-GM1 IgG and/or IgM response (44%). GBS cases involving a primary CMV infection were less frequent (40/264, 15%), but were severe too (mechanical ventilation: 37.5%); they occurred preferentially in young women (mean age: 35.9 years; sex-ratio MF: 0.82), often after respiratory tract symptoms (28%) or an influenza-like syndrome (15%) and were frequently associated with sensory loss (73%) and with an anti-GM2 IgM response (47%). CONCLUSION: C. jejuni and CMV proved to be major triggering agents of GBS in France. They are associated with distinct presentations, which are both severe.

Use of genotypic identification by sodA sequencing in a prospective study to examine the distribution of coagulase-negative Staphylococcus species among strains recovered during septic orthopedic surgery and evaluate their significance.

A total of 212 coagulase-negative Staphylococcus strains recovered prospectively during 119 surgeries for proven or suspected bone and joint infection (BJI) were identified by sodA sequencing. These strains were identified as 151 Staphylococcus epidermidis isolates, 15 S. warneri isolates, 14 S. capitis isolates, 9 S. hominis isolates, 6 S. lugdunensis isolates, 5 S. haemolyticus isolates, 4 S. caprae isolates, 4 S. pasteuri isolates, 3 S. simulans isolates, and 1 S. cohnii isolate. Only S. epidermidis, S. lugdunensis, S. capitis, and S. caprae were found to be infecting organisms and were involved, respectively, in 35 (81.4%), 3 (7.0%), 3 (7.0%), and 2 (4.6%) cases of BJI.

Use of sodA sequencing for the identification of clinical isolates of coagulase-negative staphylococci.

This study evaluated the possible advantages provided by a genotypic method over commercially available biochemical systems for the identification of clinical isolates of coagulase-negative staphylococci (CNS). Partial sequencing of the sodA gene was performed for 168 coagulase-negative clinical isolates of staphylococci identified previously with the ID32 STAPH system. Of these, 101 (60.1%) were identified to the species level with ID32 STAPH, while 67 (39.9%) were misidentified or not identified with certainty. Sequencing of sodA proved useful for resolving all ambiguities or inconclusive identifications generated by the commercially available biochemical identification system.

Variations of HSV-1 glycoprotein B in human herpes simplex encephalitis.

The factors which cause herpes simplex encephalitis (HSE) to occur among herpes simplex virus type 1 (HSV-1) infected humans are not understood. In experimental models, HSV-1 neuroinvasiveness is influenced by amino acid changes in HSV glycoproteins D (gD) or B (gB), which are essential to the virus infectivity and to the induction of host immune responses. To test the possible involvement of these glycoproteins in human HSE, we compared CSF-derived sequences of these genes with those obtained from peripheral HSV-1 isolates. We have previously shown the conservation of gD in 10 HSE samples. Here, we show that the functional domains of gB involved in cell penetration and cell fusion, and the major antigenic domains D2a, D2b and Dd5a were highly conserved. In the gB amino-terminal domain, we distinguished several alleles that were common to HSE and peripheral isolates, and identified in only three out of fifteen HSE cases, a variation that was not encountered in 20 control strains. Overall, there were no striking differences between peripheral and HSE gBs. These results suggest that gB alone may not be responsible for neuroinvasiveness nor human neuropathogenicity.