The impact of improper empirical usage of antipseudomonals on admission to an acute care hospital

Implications of deduplication on the detection rates of multidrug-resistant organism (MDRO) in various specimens: insights from the hospital infection surveillance program

BACKGROUND

Currently, different guidelines recommend using different methods to determine whether deduplication is necessary when determining the detection rates of multidrug-resistant organisms (MDROs). However, few studies have investigated the effect of deduplication on MDRO monitoring data. In this study, we aimed to investigate the influence of deduplication on the detection rates of MDROs in different specimens to assess its impact on infection surveillance outcomes.

METHODS

Samples were collected from hospitalized patients admitted between January 2022 and December 2022; four types of specimens were collected from key monitored MDROs, including sputum samples, urine samples, blood samples, and bronchoalveolar lavage fluid (BALF) samples. In this study, we compared and analysed the detection rates of carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Escherichia coli (CRECO), carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and methicillin-resistant Staphylococcus aureus (MRSA) under two conditions: with and without deduplication.

RESULTS

When all specimens were included, the detection rates of CRKP, CRAB, CRPA, and MRSA without deduplication (33.52%, 77.24%, 44.56%, and 56.58%, respectively) were significantly greater than those with deduplication (24.78%, 66.25%, 36.24%, and 50.83%, respectively) (all P < 0.05). The detection rates in sputum samples were significantly different between samples without duplication (28.39%, 76.19%, 46.95%, and 70.43%) and those with deduplication (19.99%, 63.00%, 38.05%, and 64.50%) (all P < 0.05). When deduplication was not performed, the rate of detection of CRKP in urine samples reached 30.05%, surpassing the rate observed with deduplication (21.56%) (P < 0.05). In BALF specimens, the detection rates of CRKP and CRPA without deduplication (39.78% and 53.23%, respectively) were greater than those with deduplication (31.62% and 42.20%, respectively) (P < 0.05). In blood samples, deduplication did not have a significant impact on the detection rates of MDROs.

CONCLUSION

Deduplication had a significant effect on the detection rates of MDROs in sputum, urine, and BALF samples. Based on these data, we call for the Infection Prevention and Control Organization to align its analysis rules with those of the Bacterial Resistance Surveillance Organization when monitoring MDRO detection rates.

Study on the Detection and Infection Distribution of Multidrug-Resistant Organisms in Different Specimens

OBJECTIVE

To analyze the infection and distribution of multidrug-resistant organisms (MDRO) in different clinical specimens, thereby providing a reference for clinical diagnosis and treatment and prevention and control.

PATIENT AND METHODS

2314 strains of MDRO isolated from clinical specimens in the First Affiliated Hospital of Nanjing Medical University from January to December 2020. MDRO were collected by Information System. The detection rate of MDRO, infection rate, the proportion of infection, and detection rate of MDRO infection in different specimens were analyzed.

RESULTS

The top three specimens in the detection rate of MDRO were BALF (60.71%), sputum (33.68%), and blood (28.79%). The top three specimens in the proportion of MDRO infection were blood (97.74), other sterile body fluids (90.35%), and BALF (90.20%). The top three specimens in the MDRO infection rate were BALF (9.75%), sputum (3.07%), and secretions (2.90%). The top three specimens in the detection rate of MDRO infection were sputum (0.63‰), other sterile body fluids (0.13‰), and secretions (0.11‰).

CONCLUSION

The detection and infection distribution of MDRO vary greatly in different specimens. The submission of sterile body fluids for examination should be strengthened and the standard of sample collection should be highlighted.

Association between duration of antipseudomonal beta-lactam therapy and Clostridioides difficile infections in monomicrobial Enterobacterales bloodstream infections at an academic medical center

Objective:

To evaluate the effects early de-escalation of antipseudomonal β-lactam (APBL) on 90-day CDI risk in Enterobacterales bloodstream infections (BSIs).

Design:

Retrospective cohort analysis.

Setting:

An academic medical center in South Carolina.

Patients:

We included patients aged >18 years with monomicrobial BSIs with Enterobacterales who received APBL between July 1, 2015, and June 30, 2020.

Methods:

Rates of CDI were compared between patients who received an APBL for >72 hours and <72 hours, followed by comparison between formulary APBLs utilized.

Results:

In total, 447 patients were included; 292 and 155 patients received APBL for < 72 hours and > 72 hours, respectively. The incidences of CDI for <72 hours compared to >72 hours were 2.4% and 6.5%, respectively (unadjusted hazard ratio [HR], 2.70; 95% confidence interval [CI], 1.03–7.10; P = .04). This difference was not statistically significant in the adjusted model (HR, 2.66; 95% CI, 0.97–7.31; P = .06). Meropenem was associated with an increased risk of CDI when compared with all other formulary APBLs: 4 (26.7%) of 15 versus 13 (3.0%) of 432 (P < .001).

Conclusions:

Utilization of an APBL for >72 hours was associated with a statistically significant increase in the incidence of CDI in an unadjusted model and with a numerically higher CDI incidence in the adjusted model. Meropenem was the formulary APBL that carried the highest risk of CDI. The results of this study provide further evidence supporting active antimicrobial stewardship to reduce unnecessary broad-spectrum antibiotics in the effort to alleviate the burden that CDI imposes on the healthcare system.

Mechanism of the lethal effect of Riparin E against bacterial and yeast strains

Riparins are alkamides naturally found in the fruits of Aniba riparia (Nees) Mez, but currently synthetic molecules as Riparin E (Rip-E) can be obtained. Potential biological of Rip-E as schistosomicidal agent against Schistosoma mansoni worms, as well as against Staphylococcus aureus strains has already been described. However, the mechanism of action related to antimicrobial activity of Rip-E against bacterial or fungi species has not yet been reported. This study had as objective to evaluate the Rip-E antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as against yeast species of clinical importance. Minimal inhibitory concentrations of the compound against bacterial and yeast strains were determined by microdilution method. To verify if a possible lethal effect caused by Rip-E were related to plasma membrane damage, microbial cells treated with Rip-E were stained with 7-aminoactinomycin D (7-AAD) and analyzed by flow cytometry. Rip-E showed a bactericide effect against Gram-positive species S. aureus and S. epidermidis, as well as, against Gram-negative species Escherichia coli and Salmonella enterica Typhimurium, but was inactive against Pseudomonas aeruginosa. Moreover, Rip-E showed activity against fungi species Candida albicans and C. tropicalis. S. aureus, E. coli and C. albicans cells treated with Rip-E were marked with 7-aminoactinomycin D (7-AAD) indicating that Rip-E can cause plasma membrane damage, acting as a potential microbicide agent for prevention or treatment of infectious diseases.