Functional study of type II-A CRISPR-Cas system from different phylogentic lineages of <em>Streptococcus agalactiae</em>

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Group B Streptococcus vaginal carriage in pregnant women deciphered by CRISPR analysis

International audience(GBS) vaginal carriage populations in pregnant women. For this purpose, we studied each isolate present in a primary culture of a vaginal swab using a new approach based on Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) locus analysis. To evaluate the CRISPR array composition rapidly, a Restriction Fragment Length Polymorphism (RFLP) analysis was performed. For each different pattern observed, the CRISPR array was sequenced and capsular typing and Multi Locus Sequence Typing (MLST) were performed.A total of 970 isolates from ten women were analyzed by CRISPR-RFLP. Each woman carrying GBS isolates presented one to five specific "personal" patterns. Five women shared isolates with specific and unique restriction patterns, suggesting the carriage of a single GBS clone. Different patterns were observed among isolates from the other five women. For three of these, CRISPR locus sequencing highlighted low internal modifications in the locus backbone, whereas there were high modifications for the last two women, suggesting the carriage of two different clones. These two clones were closely related (same ancestral spacer(s), same capsular type and, in one case, same ST), but shared different antibiotic resistance patterns in pairs.Eight out of 10 women were colonized by a single GBS clone, while two of them were colonized by two strains, leading to a risk of selection of more virulent and/or resistant clones during antibiotic prophylaxis. This CRISPR analysis made it possible to separate isolates belonging to a single capsular type and ST, highlighting the greater discriminating power of this approach

Etude fonctionnelle du sytème CRISPR/Cas de type II-A de <em>Streptocuccus agalactiae</em> en fonction des lignées phylogénétiques

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Étude fonctionnelle du systeme CRISPR/CAS de type II-A de <em>Streptococcus agalactiae</em> en fonction des lignées phylogénétiques

National audienc

Distribution, Diversity and Roles of CRISPR-Cas Systems in Human and Animal Pathogenic Streptococci

International audienceStreptococci form a wide group of bacteria and are involved in both human and animal pathologies. Among pathogenic isolates, differences have been highlighted especially concerning their adaptation and virulence profiles. CRISPR-Cas systems have been identified in bacteria and many streptococci harbor one or more systems, particularly subtypes I-C, II-A, and III-A. Since the demonstration that CRISPR-Cas act as an adaptive immune system in Streptococcus thermophilus , a lactic bacteria, the diversity and role of CRISPR-Cas were extended to many germs and functions were enlarged. Among those, the genome editing tool based on the properties of Cas endonucleases is used worldwide, and the recent attribution of the Nobel Prize illustrates the importance of this tool in the scientific world. Another application is CRISPR loci analysis, which allows to easily characterize isolates in order to understand the interactions of bacteria with their environment and visualize species evolution. In this review, we focused on the distribution, diversity and roles of CRISPR-Cas systems in the main pathogenic streptococci

Examen cytologique d’un liquide céphalorachidien après administration intrathécale de cytarabine liposomale

International audienceThe patient is a 36 year old female who presented breast cancer with leptomeningeal involvement. A systematic lumbar puncture was performed and sent to the laboratory for CSF analysis. CSF examination using wet mount preparation showed a large number of round spherules. After discussion with the ordering physician, we learnt that the patient had received intrathecal liposomal cytarabine injection 19 days earlier. Cytarabine liposomes are spherules with a granular interior and range in size from 10-30 μm. It can be confused with leukocytes and lead to spurious elevation of CSF leukocytes count. Care needs to be taken in interpreting CSF results in patients who have received intrathecal liposomal cytarabine

Group B Streptococcus CRISPR1 Typing of Maternal, Fetal, and Neonatal Infectious Disease Isolates Highlights the Importance of CC1 in In Utero Fetal Death

ABSTRACT We performed a descriptive analysis of group B Streptococcus (GBS) isolates responsible for maternal and fetal infectious diseases from 2004 to 2020 at the University Hospital of Tours, France. This represents 115 isolates, including 35 isolates responsible for early-onset disease (EOD), 48 isolates responsible for late-onset disease (LOD), and 32 isolates from maternal infections. Among the 32 isolates associated with maternal infection, 9 were isolated in the context of chorioamnionitis associated with in utero fetal death. Analysis of neonatal infection distribution over time highlighted the decrease in EOD since the early 2000s, while LOD incidence has remained relatively stable. All GBS isolates were analyzed by sequencing their CRISPR1 locus, which is an efficient way to determine the phylogenetic affiliation of strains, as it correlates with the lineages defined by multilocus sequence typing (MLST). Thus, the CRISPR1 typing method allowed us to assign a clonal complex (CC) to all isolates; among these isolates, CC17 was predominant (60/115, 52%), and the other main CCs, such as CC1 (19/115, 17%), CC10 (9/115, 8%), CC19 (8/115, 7%), and CC23 (15/115, 13%), were also identified. As expected, CC17 isolates (39/48, 81.3%) represented the majority of LOD isolates. Unexpectedly, we found mainly CC1 isolates (6/9) and no CC17 isolates that were responsible for in utero fetal death. Such a result highlights the possibility of a particular role of this CC in in utero infection, and further investigations should be conducted on a larger group of GBS isolated in a context of in utero fetal death. IMPORTANCE Group B Streptococcus is the leading bacterium responsible for maternal and neonatal infections worldwide, also involved in preterm birth, stillbirth, and fetal death. In this study, we determined the clonal complex of all GBS isolates responsible for neonatal diseases (early- and late-onset diseases) and maternal invasive infections, including chorioamnionitis associated with in utero fetal death. All GBS was isolated at the University Hospital of Tours from 2004 to 2020. We described the local group B Streptococcus epidemiology, which confirmed national and international data concerning neonatal disease incidence and clonal complex distribution. Indeed, neonatal diseases are mainly characterized by CC17 isolates, especially in late-onset disease. Interestingly, we identified mainly CC1 isolates responsible for in utero fetal death. CC1 could have a particular role in this context, and such a result should be confirmed on a larger group of GBS isolated from in utero fetal death

Seven Years Leptospirosis Follow-Up in a Critical Care Unit of a French Metropolitan Hospital; Role of Real Time PCR for a Quick and Acute Diagnosis

International audience(1) Background: Leptospirosis infection can lead to multiple organ failure, requiring hospitalization in an intensive care unit for supportive care, along with initiation of an adapted antibiotic therapy. Achieving a quick diagnosis is decisive in the management of these patients. (2) Methods: We present here a review of leptospirosis cases diagnosed in the intensive care unit of our hospital over seven years. Clinical and biological data were gathered, and we compared the differences in terms of diagnostic method. (3) Results: Molecular biology method by Polymerase Chain Reaction (PCR) allowed quick and reliable diagnosis when performed in the first days after the symptoms began. Moreover, we identified that sampling blood and urine for PCR was more efficient than performing PCR on only one type of biological sample. (4) Conclusions: Our results confirm the efficiency of PCR for the quick diagnosis of leptospirosis and suggest that testing both blood and urine early in the disease might improve diagnosis

Whole-genome sequencing confirms the coexistence of different colonizing Group B Streptococcus isolates underscored by CRISPR typing

International audienceStreptococcus agalactiae is a major pathogen and is the leading cause of neonatal infections in industrialized countries. The diversity of strains isolated from two pregnant women was investigated. Here, we present the draft genome sequences of strains W8A2, W8A6, W10E2, and W10F3, obtained in order to ascertain their hylogenetic affiliation