Apport de l'approche syndromique dans le diagnostic rapide des infections urinaires graves et à risque de complication

Severe urinary tract infections (UTI) require rapid and targeted antibiotic therapy. To date, the diagnosis of UTI is based on urine culture with antimicrobial susceptibility testing results available in 48 hours. The Unyvero® system (Curetis, Germany) is a multiplex PCR made for the syndromic approach. The Unyvero UTI enables the identification of microorganisms and the detection of resistance genes, in less than 5 hours. The aim of this work was to evaluate the performance of this kit for the rapid diagnosis of severe UTI. 113 urinary samples from patients with severe UTI or UTI with risk of complication were collected in tertiary hospital of Caen and analysed by classical method (culture) and with the Unyvero UTI® kit. Concerning microorganisms identification, performances were good with specificity and NPV at 98.3 % and 99. 9% respectively, but insufficient for sensitivity and PPV, with only 68.7 % and 50.0 %, respectively. Four resistance genes were mainly detected (blaCTX-M, mecA, qnrB / S and sul1) with good values of NPV (63.4 – 100 %) but their presence should not phenotypically be confirmed in many cases (PPV from 8,7 to 94.4 %). Compared to the culture, the Unyvero® UTI kit enables a certain gain of time concerning the result reporting time. This approach is complementary to the culture and should be reserved for severe UTIs that require early antibiotic therapy.Les infections du tractus urinaires (ITU) graves nécessitent une antibiothérapie adaptée précoce. À ce jour, le diagnostic des ITU est basé sur l'ECBU avec une mise en culture dont le délai de rendu de l'antibiogramme est en général de 48 heures. Le système Unyvero® (Curetis, Allemagne) est un automate de PCR multiplexée dédié à l'approche syndromique. Le kit Unyvero UTI permet en moins de 5 heures l'identification de 25 micro-organismes et la détection de 15 gènes de résistance. Le but de ce travail a été d'évaluer pour la première fois les performances de ce kit pour le diagnostic rapide des ITU. Pour cela, 113 échantillons urinaires de patients présentant une ITU grave ou à risque de complication collectés au CHU de Caen ont été inclus et analysés par méthode classique (ECBU) et avec le kit Unyvero® UTI. Concernant l'identification des micro-organismes, les performances étaient bonnes avec une spécificité et une VPN à 98,3 % et 99,9 % respectivement, mais insuffisantes concernant la sensibilité et la VPP, de 68,7 % et 50,0 % respectivement. Quatre gènes de résistance ont été principalement détectés (blaCTX-M, mecA, qnrB/S et sul1) avec de bonnes valeurs de VPN (63,4 –100 %) mais leur présence n'a pas pu être confirmée phénotypiquement dans de nombreux cas (VPP de 8,7 à 94,4 %). Par rapport à l'ECBU, le kit Unyvero® UTI a permis un gain de temps considérable dans le délai de rendu des résultats. Cette approche est complémentaire de l'ECBU et doit être réservée aux IU graves pour lesquelles l'instauration d'une antibiothérapie ciblée et précoce est nécessaire

Spectrometric Characterization of Clinical and Environmental Isolates of Aspergillus Series Versicolores

Aspergillus series Versicolores are molds distributed among 17 species, commonly found in our environment, and responsible for infections. Since 2022, a new taxonomy has grouped them into 4 major lineages: A. versicolor, A. subversicolor, A. sydowii, and A. creber. Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) could be a faster and more cost-effective alternative to molecular techniques for identifying them by developing a local database. To evaluate this technique, 30 isolates from Aspergillus series Versicolores were used. A total of 59 main spectra profiles (MSPs) were created in the local database. This protocol enabled accurate identification of 100% of the extracted isolates, of which 97% (29/30) were correctly identified with a log score ≥ 2.00. Some MSPs recorded as Aspergillus versicolor in the supplier’s database could lead to false identifications as they did not match with the correct lineages. Although the local database is still limited in the number and diversity of species of Aspergillus series Versicolores, it is sufficiently effective for correct lineage identification according to the latest taxonomic revision, and better than the MALDI-TOF MS supplier’s database. This technology could improve the speed and accuracy of routine fungal identification for these species

Paradoxical High-Level Spiramycin Resistance and Erythromycin Susceptibility Due to 23S rRNA Mutation in Streptococcus constellatus

International audienceObjectives: The aim of the study was to characterize phenotypically and genotypically an uncommon mechanism of resistance to macrolides, lincosamides, and streptogramins (MLS) in a Streptococcus milleri group clinical isolate.Materials and Methods: The isolate UCN96 was recovered from an osteoradionecrosis wound, and was identified using the matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and the partial sequencing of the sodA gene. Antimicrobial susceptibility testing were carried out by the disk diffusion method and minimal inhibitory concentrations (MICs) were determined by the broth microdilution technique. PCR screening was performed for MLS resistance genes described in Gram-positive bacteria. Specific mutations in the ribosomal proteins L3-, L4-, and L22-encoding genes were also screened and those in domain V of the 23S rRNA gene (rrl). The number of mutated copies of the rrl gene was determined using amplification-refractory mutation system quantitative-polymerase chain reaction (qPCR) analysis.Results: The clinical isolate UCN96 was unambiguously identified as Streptococcus constellatus. It was susceptible to all macrolides and lincosamides (ML) antibiotics except spiramycin (MIC >256 mg/L) while it was also resistant to streptogramins. Screening for all acquired resistance genes was negative and no mutation was found in genes coding for L3, L4, and L22 ribosomal proteins. Of interest, a single mutation, A2062C (according to Escherichia coli numbering), was detected in the domain V of 23S rRNA.Conclusion: Mutations at the position 2062 of 23S rRNA have been detected once in Streptococcus pneumoniae, and not yet in other Streptococcus spp. This mechanism is very likely uncommon in Gram-positive bacteria because different copies of 23S rRNA operons should be mutated for development of such a resistance pattern

Multicenter evaluation of the Toxoplasma gondii Real-TM (Sacace) kit performance for the molecular diagnosis of toxoplasmosis

International audienceABSTRACT The molecular detection of Toxoplasma gondii DNA is a key tool for the diagnosis of disseminated and congenital toxoplasmosis. This multicentric study from the Molecular Biology Pole of the French National Reference Center for toxoplasmosis aimed to evaluate Toxoplasma gondii Real-TM PCR kit (Sacace). The study compared the analytical and clinical performances of this PCR assay with the reference PCRs used in proficient laboratories. PCR efficiencies varied from 90% to 112%; linearity zone extended over four log units (R 2 > 0.99) and limit of detection varied from 0.01 to ≤1 Tg/mL depending on the center. Determined on 173 cryopreserved DNAs from a large range of clinical specimens, clinical sensitivity was 100% [106/106; 95 confidence interval (CI): 96.5%–100%] and specificity was 100% (67/67; 95 CI: 94.6%–100%). The study revealed two potential limitations of the Sacace PCR assay: the first was the inconsistency of the internal control (IC) when added to the PCR mixture. This point was not found under routine conditions when the IC was added during the extraction step. The second is a lack of practicality, as the mixture is distributed over several vials, requiring numerous pipetting operations. Overall, this study provides useful information for the molecular diagnosis of toxoplasmosis; the analytical and clinical performances of the Sacace PCR kit were satisfactory, the kit having sensitivity and specificity similar to those of expert center methods and being able to detect low parasite loads, at levels where multiplicative analysis gives inconsistently positive results. Finally, the study recommends multiplicative analysis in particular for amniotic fluids, aqueous humor, and other single specimens

Epidemiological and clinical study of microsporidiosis in French kidney transplant recipients from 2005 to 2019: TRANS‐SPORE registry

International audienceMicrosporidiosis is an emerging opportunistic infection in renal transplantation (RT) recipients. We aimed to describe its clinical presentation and treatment

Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study

We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care