ABSTRACT
Objectives: This study aimed to delineate the characteristics and outcomes of gram-negative bacteremia (GNB) in oncology patients; analyze the risk factors for multi-drug-resistant (MDR) GNB; and assess its impact on the recurrence of bloodstream infection (BSI), hospital stay, and 30-day mortality. Methods: Data, including demographics, clinical features, common cancers, and microbiologic findings, were collected retrospectively from electronic medical records of patients admitted with solid tumors and BSI episodes between January and December 2022. Fisher's exact tests were used to determine the effect of MDR-GNB on 30-day mortality and BSI recurrence. The Wilcoxon rank-sum test assessed the differences in the length of hospital stay. Logistic regression models identified the risk factors for MDR-GNB. Results: Among 1074 patients, 77 episodes of GNB bacteremia occurred in 59 individuals (47% male, median age 57.4 years). Of these, 37 (48%) were MDR-GNB. Carbapenem resistance was noted in 9.1% of GNB episodes. Previous antibiotic use was significantly associated with MDR-GNB (odds ratio 7.82; 95% confidence interval 2.52-24). MDR-GNB was linked to longer hospital stays (median 23 vs 10.5 days, P = 0.003) and higher recurrence rates than non-MDR-GNB (35.13% vs 5.0%, P <0.001). However, 30-day mortality did not significantly differ between the groups (35.14% vs 32.5%, P = 0.81). Conclusion: Previous antibiotic use predicted MDR-GNB in patients with solid tumor. MDR-GNB bacteremia increased the length of hospital stay and risk of recurrence compared with non-MDR-GNB bacteremia.
ABSTRACT
A new method, based on liquid chromatography--electrospray/tandem mass spectrometry, for the determination of abscisic acid (ABA), an essential plant hormone that regulates key metabolic pathways and responses to environmental cues, has been developed. Substantial changes in extraction procedures are also proposed. Data indicate that the organic solvents classically used as extraction buffers can be substituted by an aqueous solution, resulting in the same amounts of extracted ABA. The new method, which uses minute amounts of plant tissue, has an estimated limit of detection below 50 pmol ABA/g, and the sensitivity of the technique allows the analysis of ABA in crude plant extracts. Overall, this new rapid, sensitive and accurate procedure to determine ABA will allow analysis of multiple samples in a short time and represents a clear advantage in comparison with the conventional procedures involving many preparative steps and large amounts of plant tissue.