14-Year Epidemiologic study of Pseudomonas aeruginosa bloodstream infection incidence and resistance in the Veterans Health Administration system, 2009-2022.

Background: Multidrug resistant Pseudomonas aeruginosa (PA) represents a serious threat to hospitalized patients. Characterizing the incidence of PA infection and degree of resistance can inform empiric treatment and preventative measures. Objectives: We sought to describe trends in incidence and resistance characteristics of PA bloodstream infections (BSI) observed within the Veterans Health Administration (VHA) system and identify factors contributing to higher observed mortality within this population. Methods: We characterized demographic and clinical features of unique patients among the VHA population presenting with their first episode of PA-BSI between 2009 and 2022 and summarized trends related to mortality and resistance phenotype based on year and geographical location. We additionally used logistic regression analysis to identify predictors of 30-day mortality among this cohort. Results: We identified 8039 PA-BSIs during the study period, 32.7% of which were hospital onset. Annual PA-BSI cases decreased by 35.8%, and resistance among all antimicrobial classes decreased during the study period, while the proportion of patients receiving early active treatment based on susceptibility testing results increased. Average 30-day mortality rate was 23.3%. Higher Charlson Comorbidity Index, higher mAPACHE score, VHA facility complexity 1b and hospital-onset cases were associated with higher mortality, and early active treatment was associated with lower mortality. Conclusions: PA-BSI resistance decreased across the VHA system during the study period. Further investigation of antimicrobial stewardship measures possibly contributing to the observed decreased resistance in this cohort and identification of measures to improve on the high mortality associated with PA-BSI in the VHA population is warranted.

Association of COVID-19 coinfection with increased mortality among patients with Pseudomonas aeruginosa bloodstream infection in the Veterans Health Administration system.

Objective: Pseudomonas aeruginosa bloodstream infection (PA-BSI) and COVID-19 are independently associated with high mortality. We sought to demonstrate the impact of COVID-19 coinfection on patients with PA-BSI. Design: Retrospective cohort study. Setting: Veterans Health Administration. Patients: Hospitalized patients with PA-BSI in pre-COVID-19 (January 2009 to December 2019) and COVID-19 (January 2020 to June 2022) periods. Patients in the COVID-19 period were further stratified by the presence or absence of concomitant COVID-19 infection. Methods: We characterized trends in resistance, treatment, and mortality over the study period. Multivariable logistic regression and modified Poisson analyses were used to determine the association between COVID-19 and mortality among patients with PA-BSI. Additional predictors included demographics, comorbidities, disease severity, antimicrobial susceptibility, and treatment. Results: A total of 6,714 patients with PA-BSI were identified. Throughout the study period, PA resistance rates decreased. Mortality decreased during the pre-COVID-19 period and increased during the COVID-19 period. Mortality was not significantly different between pre-COVID-19 (24.5%, 95% confidence interval [CI] 23.3-28.6) and COVID-19 period/COVID-negative (26.0%, 95% CI 23.5-28.6) patients, but it was significantly higher in COVID-19 period/COVID-positive patients (47.2%, 35.3-59.3). In the modified Poisson analysis, COVID-19 coinfection was associated with higher mortality (relative risk 1.44, 95% CI 1.01-2.06). Higher Charlson Comorbidity Index, higher modified Acute Physiology and Chronic Health Evaluation score, and no targeted PA-BSI treatment within 48 h were also predictors of higher mortality. Conclusions: Higher mortality was observed in patients with COVID-19 coinfection among patients with PA-BSI. Future studies should explore this relationship in other settings and investigate potential SARS-CoV-2 and PA synergy.

Using Active Surveillance to Identify Monoclonal Antibody Candidates Among COVID-19-Positive Veterans in the Atlanta VA Health Care System.

Background: Strategies for optimizing identification and outreach to potential candidates for monoclonal antibody (Mab) therapy for COVID-19 are not clear. Using a centralized, active surveillance system, the Atlanta Veterans Affairs Health Care System (AVAHCS) infectious disease (ID) team identified candidates for Mab infusion and provided treatment. Observations: As part of a quality improvement project from December 28, 2020, to August 31, 2021, a clinical team consisting of ID pharmacists and physicians reviewed each outpatient with a positive COVID-19 polymerase chain reaction test daily at the AVAHCS. The clinical team used Emergency Use Authorization (EUA) criteria to determine eligibility. Eligible patients were contacted on the same day of review via telephone to confirm eligibility and obtain verbal consent. Telehealth follow-up occurred on day 1 and day 7 postinfusion to assess for adverse events. In total, 2028 patients with COVID-19 were identified; 289 patients (14%) were eligible, and 132 (46%) received Mab therapy. Similar to AVAHCS demographics, a majority of those who received Mab therapy were non-Hispanic Black patients (65%). The most common comorbidities were hypertension (59%) and diabetes (37%). The median time from symptom onset to positive COVID-19 polymerase chain reaction (PCR) test result was 6 days (range, 0-9), and the median time from positive COVID-19 PCR test result to Mab infusion was 2 days (range, 0-8). Twelve patients (9%) required hospitalization for worsening COVID-19 symptoms postinfusion. No deaths occurred. Conclusions: Combining laboratory surveillance and active screening led to high uptake of Mab therapy and minimized delay from symptom onset to Mab infusion, thereby optimizing outpatient treatment of COVID-19. This approach also successfully screened and treated Black patients in the AVAHCS population.

Evaluation of programmatic changes to an antimicrobial stewardship program with house officer feedback.

RATIONALE, AIMS AND OBJECTIVES: A collegial relationship between prescribers and antimicrobial stewards, along with an appreciation of the importance of antimicrobial stewardship, is essential for optimal functioning of an antimicrobial stewardship program (ASP). Programmatic adjustments based on feedback may be beneficial to the success of ASPs. The objective of this study is to assess the experience of house officers with the ASP and the effect of programmatic improvements. METHODS: A survey of house officers at an academic medical centre was conducted assessing their experience with the ASP before (2008) and after (2010) programmatic interventions were instituted. RESULTS: Of 225 house officer surveys sent, we received 97 responses (88% from medical doctors). The majority indicated that ASP was either very or somewhat important in fighting antibiotic resistance (100%), improving patient care (97%), preventing medication errors (91%) and containing health care costs (89%). Ninety-one per cent indicated either a very good or good educational experience with the ASP. The ASP often reminded respondents of a patient's allergy (31%), to adjust for renal function (78%), and 38% were prevented from making a medication error. Comparing 2008 and 2010, a higher proportion of respondents in 2010 said they had a very good or good educational experience with ASP [84% versus 98%, odds ratio (OR) = 8.40, P = 0.022] and a lower proportion of respondents reported confusion about ASP procedures (59% versus 39%, OR = 0.43, P = 0.048). CONCLUSIONS: House officer feedback resulted in ASP policy changes which improved the ASP experience.