Inter-laboratory variability of caspofungin MICs for Nakaseomyces glabrata isolates - an Irish tertiary hospital experience.

Background: Nakaseomyces glabrata, formerly Candida glabrata, is an opportunistic yeast and emerging cause of human infections. The use of broth microdilution (BMD) methodologies for caspofungin (CSP) antifungal susceptibility testing (AFST) against N. glabrata is reported to be prone to high inter-laboratory variation. We aimed to compare CSP MICs of N. glabrata isolates from our institution with those obtained by the Reference Laboratory for the same isolates. Methods: All clinically significant N. glabrata isolates from 2019 to 2021 inclusive were reviewed. AFST was performed locally using the VITEK2 system with the AST-YS08 card, while E-tests were performed at the Mycology Reference Laboratory (MRL), and agreement between these two methods was evaluated - categorical and essential. Results: Forty-one isolates were reviewed during the study period - 30 from blood cultures, seven from intra-operative theatre specimens and four from sterile site drain fluids. Despite an essential agreement of 100 % within ±2 log2 dilutions, marked discrepancies were noted in interpretative breakpoints between assays with 17 Minor and 16 Major category errors. Categorical agreement was 19.5 %, with the VITEK2 over-estimating resistance. A Mann-Whitney U-test assessed the relationship of MICs across the AFST modalities, and a statistically significant difference was noted, P<0.01, with a higher mean rank for VITKEK2 outputs. Conclusion: While the VITEK2 system is highly applicable, its performance for CSP AFST is unreliable and potentially results in the mis-classification of susceptible isolates as highlighted in our study. The use of VITEK2 AST-YS08 micafungin as a sentinel echinocandin should be explored and/or the evaluation of CSP-specific E-tests as utilized by the MRL. These methods appear more consistent and less prone to the variation seen with BMD for CSP.

Antimicrobial susceptibility patterns of community-acquired uropathogenic Escherichia coli, Dublin 2010-2022.

Background: Escherichia coli is a common cause of urinary tract infections. Due to the increase in antimicrobial resistance (AMR) and global differences in antimicrobial susceptibility data, routine assessment of local antimicrobial susceptibility patterns is necessary to guide the selection of appropriate empirical therapy. The aim of this study was to evaluate the antimicrobial susceptibility patterns of community-acquired uropathogenic Escherichia coli within a catchment area in Dublin over a 13 year period, 2010-2022. Methods: All mid-stream urine samples received from local general practitioners in which there was significant E. coli bacteriuria during the study period, 2010-2022, were included in the analysis. Antimicrobial susceptibility testing was performed by disc diffusion as per the European Committee on Antimicrobial Susceptibility Testing recommendations. Results: An average of 11 407 urine samples per month had significant bacteriuria, with E. coli accounting for an average of 67 % of those. Overall AMR rates were highest for ampicillin (53.9 %), followed by trimethoprim (32.4 %), gentamicin (18.6 %), co-amoxiclav (16.5 %), ciprofloxacin (12.3 %), cephalexin (8.3 %), cefpodoxime (6.8 %) and nitrofurantoin (2 %). While rates appeared grossly static, statistically significant reduced resistance rates were noted for co-amoxiclav (rs=-0.95; P=<0.001), cephalexin prior to 2019 (rs=-0.783; P=0.013) and trimethoprim (rs=-0.639; P=0.019), with a statistically significant increase in non-susceptibility to cefpodoxime (rs=0.802; P=0.001). Conclusions: In order to generate efficient empirical antimicrobial prescribing guidelines, knowledge of region-specific contemporaneous antimicrobial susceptibility patterns is pivotal. Our findings support the use of nitrofurantoin or cephalexin as empirical antimicrobial therapy within our setting.

Impact of the COVID-19 pandemic on the incidence of healthcare-associated Clostridioides difficile infection in a tertiary healthcare facility in the Republic of Ireland.

Background: Clostridioides difficile is the foremost cause of nosocomial infectious diarrhoea and one of the most prevalent healthcare associated infections (HAIs). Aims: To investigate the impact of the coronavirus disease 2019 (COVID-19) pandemic on the incidence of healthcare associated C. difficile infection (HA-CDI). Methods: A retrospective study was conducted from January 2019-December 2022 inclusive at a tertiary University Hospital in Dublin, Ireland. The study period was divided into COVID-19 and non-COVID-19 periods determined in tangent with the then national incidences of COVID-19 and number of hospitalized patients with COVID-19. Analyses looked at quantity of testing performed, incidence rates and antimicrobial consumption. An independent samples t-test was used to determine significance between groups. Results: Between COVID-19 and non-COVID-19 periods, no statistically significant difference was observed among HA-CDI rates per 10,000 bed-days (2.1 cases vs 1.76 cases; P=0.34), consumption of defined daily doses per 100 bed-days of antimicrobials - all antimicrobials (83.36 vs 89.5; P=0.091), fluoroquinolones only (3.71 vs 4.46; P=0.067), third-generation cephalosporins only (4.17 vs 4.43; P=0.449), carbapenems only (3.28 vs 3.26; P=0.944) - or the number of C. difficile tests performed per 10,000 bed-days (321.81 tests vs 326.63 tests; P=0.696). Conclusions: There was no difference in the incidence rates of HA-CDI between COVID-19 and non-COVID-19 periods at our institution.

Antimicrobial susceptibility patterns of anaerobic bacteria at an Irish University Hospital over a ten-year period (2010-2020).

OBJECTIVES: In recent years various clinical studies have demonstrated poor outcomes in infections caused by anaerobic bacteria due to inappropriate therapy, directly due to emergence of resistant strains. This is a concern given that many anaerobic infections are treated empirically with metronidazole or a beta-lactam/beta-lactamase inhibitor combinations (e.g., co-amoxiclav, piperacillin-tazobactam). To date there is a paucity of available data on antimicrobial resistance trends of anaerobic bacteria in Ireland, and our study aims to determine such patterns among isolates processed at our institution over the last ten years. METHODS: Significant anaerobic bacteria isolated from clinical specimens processed at our laboratory from January 2010 to January 2020 inclusive were reviewed. Bacteria were identified using MALDI-TOF, with E-tests used for antimicrobial susceptibility testing. Data was processed through WHONET. RESULTS: A total of 2098 clinically significant anaerobic bacterial isolates from blood cultures (31%), theatre/intraoperative specimens (30%), aspirates and drain fluid (22%) and wound swabs (17%) were reviewed during the study period; with the majority of isolates being Bacteroides spp (32.79%, n = 688) and Clostridium spp (18.68%, n = 392). With isolates demonstrating well-recognised or inherent resistances excluded, overall resistance to tested antimicrobials was 6.40% to penicillin, 1.71% to metronidazole, 1.43% to co-amoxiclav, 13.63% to clindamycin, 0.43% to piperacillin-tazobactam and 0% to meropenem. CONCLUSION: Metronidazole and beta-lactam/beta-lactamase inhibitor combinations remain highly efficacious against the majority of anaerobic isolates reviewed, and can safely be used as empiric therapy in suspected anaerobic infections. However, periodic surveillance of resistance trends remains important.

Psychological impact of the COVID-19 pandemic on healthcare workers at acute hospital settings in the South-East of Ireland: an observational cohort multicentre study.

OBJECTIVE: Our study aims to understand the psychological impact of the COVID-19 pandemic among healthcare workers (HCWs) at acute hospital settings in the South-East of Ireland, as a crucial step in guiding policies and interventions to maintain their psychological well-being. DESIGN: Observational cohort study. PARTICIPANTS AND SETTING: 472 HCWs participated from two distinct acute hospital settings, A and B, in the South-East of Ireland. PRIMARY AND SECONDARY OUTCOME MEASURES: Measures of psychological distress-depression, anxiety, acute and post-traumatic stress disorder (PTSD)-as dictated by the Depression, Anxiety and Stress Scale (DASS-21) and Impact of Event Scale-Revised (IES-R). An independent sample t-test and a Mann-Whitney U test was used to determine significance of difference in continuous variables between groups. Categorical variables were assessed for significance with a χ2 test for independence. RESULTS: The DASS-21 provided independent measures of depression (mean 4.57, IQR 2-7), anxiety (mean 3.87, IQR 1-6) and stress (mean 7.41, IQR 4-10). Positive scores were reflected in 201 workers (42.6%) for depression and 213 (45.1%) for both anxiety and stress. The IES-R measured subjective distress on three subscales: intrusion (mean 1.085, IQR 0.375-1.72), avoidance (mean 1.008, IQR 0.375-1.5) and hyperarousal (mean 1.084, IQR 0.5-1.667). Overall, 195 cases (41.3%) were concerning for PTSD. Site B scored significantly higher across all parameters of depression (5.24 vs 4.08, p<0.01), anxiety (4.66 vs 3.3, p<0.01), stress (8.91 vs 6.33, p<0.01) and PTSD (0.058 vs 0.043, p<0.01). Worse outcomes were also noted in HCWs with underlying medical ailments. CONCLUSION: Psychological distress is prevalent among HCWs during the COVID-19 pandemic; screening for adverse mental and emotional outcomes and developing timely tailored preventative measures with effective feedback are vital to protect their psychological well-being, both in the immediate and long-term.

Adding value to the oil cake as a waste from oil processing industry: production of lipase and protease by Candida utilis in solid state fermentation.

Olive oil cake is a by-product from the olive oil processing industry and can be used for the lipase and protease production by Candida utilis in solid state fermentation. Different carbon and nitrogen sources were evaluated, and the results showed that the supplementation of the substrate with maltose and starch as carbon sources and yeast extract as a nitrogen source significantly increased the lipase production. The best results were obtained with maltose, whereas rather low lipase and protease activities were found with glucose and oleic acid. Response surface methodology and a five-level-three-factor central composite rotatable design were used to evaluate the effects of the initial moisture content, inoculum size and fermentation time on both lipase and protease activity levels. A lipase activity value of ≈25 U g(-1) and a protease activity value of 110 U g(-1) were obtained under the optimized fermentation conditions. An alkaline treatment of the substrate appeared to be efficient, leading to increases of 39% and 133% in the lipase and protease production, respectively. The results showed that the olive cake could be a good source for enzyme production by solid state fermentation.