Impact of Order-Set Modifications and Provider Education Following Guideline Updates on Broad-Spectrum Antibiotic Use in Patients Admitted With Community Acquired Pneumonia.

Purpose: Following updates to the Infectious Diseases Society of America (IDSA) practice guidelines for the Diagnosis and Treatment of Adults with Community-acquired Pneumonia in 2019, Hartford HealthCare implemented changes to the community acquired pneumonia (CAP) order-set in August 2020 to reflect criteria for the prescribing of broad-spectrum antimicrobial therapy. The objective of the study was to evaluate changes in broad-spectrum antibiotic days of therapy (DOT) following these order-set updates with accompanying provider education. Methods: This was a multi-center, quasi-experimental, retrospective study of patients with a diagnosis of CAP from September 1, 2019 to October 31, 2019 (pre-intervention) and September 1, 2020 to October 31, 2020 (post-intervention). Patients were identified using ICD-10 codes (A48.1, J10.00-J18.9) indicating lower respiratory tract infection. Data collected included demographics, labs and vitals, radiographic, microbiological, and antibiotic data. The primary outcome was change in broad-spectrum antibiotic DOT, specifically anti-pseudomonal ß-lactams and anti-MRSA antibiotics. Secondary outcomes included guideline-concordance of initial antibiotics, utilization of an order-set to prescribe antibiotics, and length of stay (LOS). Results: A total of 331 and 352 patients were included in the pre- and post-intervention cohorts, respectively. There were no differences in order-set usage (10% vs 11.3%, P = .642) between the pre- and post-intervention cohort, respectively. The overall duration of broad-spectrum therapy was a median of 2 days (IQR 0-8 days) in the pre-intervention period and 0 days (IQR 0-4 days) in the post-intervention period (P < .001). Patients in whom the order-set was used in the post-intervention period were more likely to have guideline-concordant regimens ([36/40] 90% vs [190/312] 60.9%; P = .003). Hospital LOS was shorter in the post-intervention cohort (4.8 days [2.9-7.2 days] vs 5.3 days [IQR 3.5-8.5 days], P = .002). Conclusion: Implementation of an updated CAP order-set with accompanying provider education was associated with reduced use of broad-spectrum antibiotics. Opportunities to improve compliance and thus further increase guideline-concordant therapy require investigation.

Variability in Zinc Concentration among Mueller-Hinton Broth Brands: Impact on Antimicrobial Susceptibility Testing of Metallo-ß-Lactamase-Producing Enterobacteriaceae.

Zinc concentrations in cation-adjusted Mueller-Hinton broth (caMHB) from different manufacturers have been found to differ. Here, we evaluated the impact of utilizing different brands and lots of commercially available caMHB on the classification of the antimicrobial susceptibility of metallo-ß-lactamase (MBL)-harboring Enterobacteriaceae We also evaluated the addition of EDTA to caMHB as a means of achieving zinc-limited media. Fifteen clinical Enterobacteriaceae isolates (harboring NDM [n = 7], VIM [n = 3], IMP [n = 2], or KPC [n = 3]) and nine different commercial lots from three caMHB manufacturers (Becton, Dickinson; Oxoid; and Sigma-Aldrich) were utilized. Zinc-limited media were prepared by the addition of EDTA at concentrations ranging from 3 to 300 µg/ml. Meropenem MICs were determined in triplicate for each lot of conventional caMHB and zinc-limited media by broth microdilution. The zinc concentration in each lot of conventional caMHB was determined by inductively coupled plasma mass spectrometry. Up to 8-fold differences in meropenem MICs were observed between the commercial lots, resulting in different classifications of susceptibility among MBL-harboring isolates. Mean zinc concentrations were highest among conventional Becton, Dickinson caMHB lots relative to those for Oxoid and Sigma-Aldrich broth. Among MBL-harboring isolates, the impact of EDTA on MICs was dependent on the lot, correlating with initial zinc availability (i.e., less MIC reduction with higher initial zinc concentrations), while MICs for KPC-harboring isolates were unchanged. In summary, zinc variability was observed among commercial lots of caMHB, resulting in different classifications of susceptibility among MBL-harboring Enterobacteriaceae The addition of EDTA at concentrations of ≥30 µg/ml was sufficient to provide a zinc-limited medium, resulting in MICs that reflect in vivo meropenem activity.

Evaluation of Timing of Antimicrobial Surgical Prophylaxis on Rates of Surgical Site Infections.

Background: Surgical site infections (SSIs) are common healthcare-associated infections, and national guidelines recommend that antimicrobial prophylaxis (AP) be administered 60 min prior to incision. However, there are limited data regarding the "most optimal" time for administration within the 60-min window. Patients and Methods: This was a multicenter, retrospective study of adult (≥18-year-old) patients that underwent an abdominal hysterectomy, colorectal surgery, or craniotomy and received AP within 60 min of incision. Incidence of SSI was compared between patients who received AP 0-30 versus 31-60 min of incision. In addition, a predefined subgroup analysis evaluated incidence of SSI for 15-min intervals within the 60-min timeframe. Results: Of the 277 patients included in the primary analysis, 233 (84.1%) and 44 (15.9%) received AP 0-30 min and 31-60 min prior to incision, respectively. SSIs were documented in 6.0% (14/233) versus 4.5% (2/44) of patients in the primary analysis (p = 0.703). In the secondary analysis, 137 (49.5%), 95 (34.3%), 34 (12.3%), and 11 (4.0%) patients received AP 0-15, 16-30, 31-45, and 46-60 min prior to incision, respectively. There was no difference in incidence of SSIs among the 15-min intervals (4.4% vs. 8.4% vs. 2.9% vs. 9.1%, p = 0.487). Of the 16 patients in this study that incurred a SSI, 5 patients had positive cultures, of which 3 contained bacteria that proved to be resistant to the antibiotic used for AP. Conclusions: The results of our analysis support current national guidelines. Future investigation of different intervals (e.g., AP 15-45 min prior to incision) may be beneficial on the basis of pharmacokinetics of routinely prescribed AP.

Plazomicin: an intravenous aminoglycoside antibacterial for the treatment of complicated urinary tract infections.

INTRODUCTION: Antimicrobial resistance continues to be a major public health concern due to the emergence and spread of multi-drug resistant (MDR) organisms, including extended spectrum ß-lactamase (ESBL) and carbapenemase producing Enterobacterales. Plazomicin is a novel aminoglycoside that demonstrates activity against MDR gram-negatives, including those producing ESBLs and most carbapenemases, and retains activity against aminoglycoside modifying enzymes as a result of structural modifications. The information discussed is meant to assist in identifying plazomicin's place in therapy and to expand the clinician's armamentarium. AREAS COVERED: Herein, we review the pharmacology, microbiology, clinical efficacy, and safety of plazomicin. To gather relevant information, a literature search was performed using PubMed, Ovid, and Google Scholar electronic databases. Search terms used include plazomicin, ACHN-490, extended spectrum ß-lactamase, ESBL, CRE, aminoglycoside modifying enzymes, and AME. Additional information was obtained from FDA review documents and research abstracts presented at international conferences. EXPERT OPINION: Plazomicin is a promising carbapenem or ß-lactam/ß-lactamase inhibitor-sparing alternative for the treatment of complicated urinary tract infections caused by MDR Enterobacterales. Although robust data for bloodstream infections and bacterial pneumonias are lacking, plazomicin may be considered in individual clinical scenarios if combination therapy is warranted provided supportive microbiological data and therapeutic drug monitoring are available.

Evaluation of a best practice alert to reduce unnecessary Clostridium difficile testing following receipt of a laxative.

INTRODUCTION: This study examined the effect of an alert notifying providers ordering Clostridium difficile PCR when their patient received a laxative within 24 hours at four hospitals. METHODS: All patients whose provider received the laxative alert when ordering C. difficile testing were examined. RESULTS: Three hundred sixty-six patients had 483 alerts triggered, with 75% overridden. While 74% of patients had ≥2 bowel movements immediately pre-order, 33% of C. difficile tests were not performed due to no stool production post-order or laboratory rejection of formed stool. Of those with completed tests, 49% had ≤1 cardinal sign of C. difficile infection (CDI) and only 18% tested positive by PCR. There were no differences in frequency of CDI signs between the PCR-positive and PCR-negative patients. CONCLUSIONS: C. difficile testing was common among patients receiving laxatives. Patients testing positive for C. difficile looked clinically similar to patients testing negative, suggesting a high false-positive rate.