Impact of the multiplex molecular FilmArray Respiratory Panel on antibiotic prescription and clinical management of immunocompromised adults with suspected acute respiratory tract infections: A retrospective before-after study / Impacto del panel respiratorio molecular multiplex FilmArray ¿ en la prescripción de antibióticos y el manejo clínico de pacientes adultos inmunocomprometidos con sospecha de infección respiratoria aguda: un estudio retrospectivo antes/después

Abstract This study aimed to assess the impact of the implementation of a rapid multiplex molecular FilmArray Respiratory Panel (FRP) on the medical management of immunocompromised patients from a community general hospital. We conducted a single-center, retrospective, and before-after study. Two periods were evaluated: before the implementation of the FRP (pre-FRP) from April 2017 to May 2018 and after the implementation of the FRP (post-FRP) from January to July 2019. The inclusion criteria were immunocompromised patients over 18 years of age with suspected acute respiratory illness tested by conventional diagnostic meth-ods (pre-FRP) or the FilmArray™ Respiratory Panel v1.7 (post-FRP). A total of 142 patients were included, 64 patients in the pre-FRP and 78 patients in the post-FRP. The positive detec-tion rate was significantly higher in the post-FRP (63% vs. 10%, p <0.01). There were more patients receiving antimicrobial treatment in the pre-FRP compared with the post-FRP period (94% vs. 68%, p <0.01). A decrease in beta-lactam (89% vs. 61%, p <0.01) and macrolide (44% vs. 13%, p < 0.01) prescriptions were observed in the post-FRP. No differences were observed in oseltamivir use (22% vs. 13%, p = 0.14), changes in antimicrobial treatment, hospital admission rate, days-reduction in droplet isolation precautions, hospital length of stay (LOS), admission to intensive care unit (ICU), LOS in ICU, treatment failure and 30-day mortality. The implementa-tion of the FRP impacted patient care by improving diagnostic yield and optimizing antimicrobial treatment in immunocompromised adult patients.

Resumen El objetivo de este estudio fue evaluar el impacto de la implementación del panel respiratorio FilmArray® (FRP), un sistema automatizado de PCR multiplex, en el estándar de cuidado de pacientes adultos inmunocomprometidos en un hospital general. Es un estudio retrospectivo de un único centro con diseno antes/después. Los periodos evaluados fueron abril 2017-mayo 2018, previo a la implementación del FRP (pre-FRP), y enero 2019-julio 2019, luego de la implementación (post-FRP). Los criterios de inclusión fueron pacientes mayores de 18 años inmunocomprometidos con sospecha de infección respiratoria aguda a los que se les realizó, en pre-FRP, diagnóstico por métodos convencionales, y en post-FRP, el panel respiratorio FRP versión 1.7. Se incluyeron un total de 142 pacientes, 64 en pre-FRP y 78 en post-FRP. La tasa de positividad fue significativamente mayor en post-FRP frente a pre-FRP (63 vs. 10%, p<0,01). Hubo más pacientes con tratamiento antimicrobiano en pre-FRP que en post-FRP (94 vs. 68%, p <0,01). En pre-FRP hubo más pacientes tratados con betalactámicos (89 vs. 61%, p <0,01) y macrólidos (44 vs. 13%, p < 0,01). No se observaron diferencias significativas en el uso de oseltamivir (22 vs. 13%, p = 0,14), cambios en los tratamientos, número de hospitalizaciones, uso de aislamientos, duración de la estadía hospitalaria, ingreso a la unidad de cuidados intensivos, estadía en dicha unidad, falla de tratamiento y mortalidad a 30 días. El uso de FRP contribuyó a la atención del paciente mejorando el rendimiento diagnóstico y optimizando la terapia antimicrobiana en pacientes adultos inmunocomprometidos.

MALDI-TOF MS-Based KPC Direct Detection from Patients' Positive Blood Culture Bottles, Short-Term Cultures, and Colonies at the Hospital.

Carbapenemase resistance in Enterobacterales is a global public health problem and rapid and effective methods for detecting these resistance mechanisms are needed urgently. Our aim was to evaluate the performance of a MALDI-TOF MS-based "Klebsiella pneumoniae carbapenemase" (KPC) detection protocol from patients' positive blood cultures, short-term cultures, and colonies in healthcare settings. Bacterial identification and KPC detection were achieved after protein extraction with organic solvents and target spot loading with suitable organic matrices. The confirmation of KPC production was performed using susceptibility tests and blaKPC amplification using PCR and sequencing. The KPC direct detection (KPC peak at approximately 28.681 Da) from patients' positive blood cultures, short-term cultures, and colonies, once bacterial identification was achieved, showed an overall sensibility and specificity of 100% (CI95: [95%, 100%] and CI95: [99%, 100%], respectively). The concordance between hospital routine bacterial identification protocol and identification using this new methodology from the same extract used for KPC detection was ≥92%. This study represents the pioneering effort to directly detect KPC using MALDI-TOF MS technology, conducted on patient-derived samples obtained from hospitals for validation purposes, in a multi-resistance global context that requires concrete actions to preserve the available therapeutic options and reduce the spread of antibiotic resistance markers.

Sustained Transmission of Neisseria gonorrhoeae Strains with High-Level Azithromycin Resistance (MIC ≥ 256 µg/mL) in Argentina, 2018 to 2022.

Azithromycin combined with ceftriaxone is the recommended dual therapy for uncomplicated gonorrhea in many countries. Nevertheless, the increasing prevalence of azithromycin resistance compromises the effectiveness of this treatment strategy. From 2018 to 2022, we collected 13 gonococcal isolates with high-level azithromycin resistance (MIC ≥ 256 µg/mL) across Argentina. Whole-genome sequencing revealed that these isolates were mainly represented by the internationally spreading Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST) genogroup G12302, containing the 23S rRNA A2059G mutation (in all four alleles) together with mosaic mtrD and mtrR promoter 2 loci. This information is important to develop targeted public health policies to control the spread of azithromycin-resistant N. gonorrhoeae in Argentina and internationally. IMPORTANCE Azithromycin resistance in Neisseria gonorrhoeae has been increasing in numerous populations worldwide, which is of concern, as azithromycin is part of the recommended dual treatment in many countries. Here, we report 13 N. gonorrhoeae isolates with high-level azithromycin resistance (MIC ≥ 256 µg/mL). This study observed that high-level azithromycin-resistant gonococcal strains have shown sustained transmission in Argentina and are related to the successful international clone NG-MAST G12302. Genomic surveillance together with real-time tracing and data-sharing networks will be crucial in controlling the spread of azithromycin resistance in gonococcus.

Community-associated Clostridioides difficile infection in a general hospital from Argentina.

Toxin-producing Clostridioides difficile infection (CDI) is the leading cause of hospital-acquired diarrhea. However, it is now recognized as a cause of diarrhea in the community. This single-center study aimed to determine the epidemiological origin of CDI cases between January 2014 and December 2019 and to compare demographic characteristics, comorbidities, risk factors, severity, and mortality of community CDI with healthcare facility-associated CDI. There were 52 CDI cases from the community (34.4%). Community patients were significantly younger (53 yo vs. 65 yo), less comorbid (Charlson Index 1.65 vs. 3.98), and less severe (only one case). The main risk factor was the use of antibiotics in the previous 90 days (65%). However, we did not find any known risk factor in 7 patients.

Impact of the multiplex molecular FilmArray Respiratory Panel on antibiotic prescription and clinical management of immunocompromised adults with suspected acute respiratory tract infections: A retrospective before-after study.

This study aimed to assess the impact of the implementation of a rapid multiplex molecular FilmArray Respiratory Panel (FRP) on the medical management of immunocompromised patients from a community general hospital. We conducted a single-center, retrospective, and before-after study. Two periods were evaluated: before the implementation of the FRP (pre-FRP) from April 2017 to May 2018 and after the implementation of the FRP (post-FRP) from January to July 2019. The inclusion criteria were immunocompromised patients over 18 years of age with suspected acute respiratory illness tested by conventional diagnostic methods (pre-FRP) or the FilmArray™ Respiratory Panel v1.7 (post-FRP). A total of 142 patients were included, 64 patients in the pre-FRP and 78 patients in the post-FRP. The positive detection rate was significantly higher in the post-FRP (63% vs. 10%, p<0.01). There were more patients receiving antimicrobial treatment in the pre-FRP compared with the post-FRP period (94% vs. 68%, p<0.01). A decrease in beta-lactam (89% vs. 61%, p<0.01) and macrolide (44% vs. 13%, p<0.01) prescriptions were observed in the post-FRP. No differences were observed in oseltamivir use (22% vs. 13%, p=0.14), changes in antimicrobial treatment, hospital admission rate, days-reduction in droplet isolation precautions, hospital length of stay (LOS), admission to intensive care unit (ICU), LOS in ICU, treatment failure and 30-day mortality. The implementation of the FRP impacted patient care by improving diagnostic yield and optimizing antimicrobial treatment in immunocompromised adult patients.

Eficacia del instrumento XP-endo Finisher y del sistema EndoActivator en la reducción/eliminación del biofilm bacteriano: un ensayo ex vivo / Ability of the XP-endo Finisher instrument and the EndoActivator system to reduce/eliminate of the bacterial biofilm: an ex vivo assay

Objetivos: Comparar ex vivo la eficacia del instrumento XP-endo Finisher y del sistema EndoActivator en la reducción/eliminación del biofilm microbiano en conductos radiculares infectados. Materiales y métodos: Se utilizaron 23 premolares inferiores humanos extraídos cuya longitud fue estandarizada en 17 mm. Todos los conductos se prepararon con el sistema WaveOne Gold Medium (#35.06). Los dientes se esterilizaron, se inocularon con Enterococcus faecalis y se separaron en dos grupos experimentales de 10 piezas cada uno. De los 3 dientes remanentes, 1 fue utilizado como control positivo y 2, como controles negativos. En el grupo 1, las soluciones irrigantes se agitaron con XP-endo Finisher. En el grupo 2, se utilizó EndoActivator. Se tomaron muestras antes de la contaminación, luego de esta y después de la agitación de los irrigantes mediante conos de papel estériles. La carga microbiana fue sembrada en agar sangre y los conos se cultivaron en caldo tripteína de soja. La remoción de la carga microbiana se determinó por la presencia o ausencia de turbiedad del medio. Las unidades formadoras de colonias (UFC) remanentes se cuantificaron y los resultados se categorizaron como R1 (≤10 UFC) o R2 (>10 UFC). Los datos fueron analizados mediante la prueba de Fisher. Resultados: No hubo diferencias significativas entre XP-endo Finisher y EndoActivator (P>0,05). El número de usos no influyó sobre la capacidad operativa de ambos instrumentos (AU)

Aim: To compare ex vivo the effectiveness of the XP-endo Finisher and the EndoActivator in biofilm reduction/ removal from infected root canals. Materials and methods: Twenty three extracted human single-rooted lower premolars were selected and standardised to 17 mm in length. All the canals were prepared with WaveOne Gold Medium reciprocating files (#35.06). The teeth were autoclaved and inoculated with Enterococcus faecalis. The infected teeth were then assigned to 2 experimental groups of 10 teeth each according to the final irrigation/agitation protocol. Of the three remaining teeth, one was used as a positive control, and the other two were used as negative controls. In Group 1 the irrigating solutions were agitated with XP-endo Finisher while in Group 2 the EndoActivator was used. All root canals were sampled before and after contamination, and again after irrigant agitation with sterile paper points. The microbial load was spread on blood agar plates and the paper points were cultured in sterile trypticase soy broth. The removal of the microbial load was determined by visual observation of the turbidity of the media and by quantification of the number of colony-forming units (UFC). The results were categorized as R1 (≤10 UFC) or R2 (>10 UFC). Data were analysed by the Fisher's exact test at P<0.05. Results: No significant differences was found between XP-endo Finisher and EndoActivator (P>0.05) regarding their effectiveness in the reduction/removal of the microbial biofilm. The number of uses of both instruments did not affect their operative performance (AU) Conclusion: XPF and EA were both equally effective for microbial biofilm reduction/removal from ex vivo infected root canals (AU)