High-Risk Patients Undergoing Holmium Laser Enucleation of the Prostate Have Fewer Infections with a Longer Course of Preoperative Antibiotics.

Introduction: There are minimal data to guide antibiotic management of patients undergoing holmium laser enucleation of the prostate (HoLEP) for benign prostatic hyperplasia. Specifically, management of high-risk patients who are catheter dependent or have positive preoperative urine cultures varies widely. We aimed to evaluate the effect of preoperative antibiotic duration on infectious complications in high-risk patients undergoing HoLEP. Methods: A multi-institutional retrospective review of patients undergoing HoLEP between 2018 and 2023 at five institutions was performed. Patients were defined as high risk if they were catheter-dependent (indwelling urethral catheter, self-catheterization, or suprapubic tube) or had a positive preoperative urine culture. These patients were categorized into long course (>3 days) or short course (≤3 days) of preoperative antibiotics. The primary outcome was 30-day infectious complications defined as a positive urine culture with symptoms. A t-test or Wilcoxon rank-sum test was used for continuous variables and Fisher's exact test was used for categorical variables. Logistic regression analysis was conducted to identify associations with infectious complications. Results: Our cohort included 407 patients, of which 146 (36%) and 261 (64%) were categorized as short course and long course of preoperative antibiotics, respectively. Median preoperative antibiotic duration was 1 day (interquartile range [IQR]: 0, 3 days) and 7 days (IQR: 5, 7 days) in the short and long cohorts, respectively. Thirty-day postoperative infectious complications occurred in 11 (7.6%) patients who received a short course of antibiotics and 5 (1.9%) patients who received a long course of antibiotics (odds ratio 0.24, 95% confidence interval 0.07-0.67; p = 0.009). Variables such as age, positive urine culture, and postoperative antibiotic duration were not significantly associated with postoperative infection after propensity score weighting. Conclusion: In high-risk patients undergoing HoLEP, infectious complications were significantly lower with a long course vs short course of antibiotics. Further prospective trials are needed to identify optimal preoperative antibiotic regimens.

Catabolism of (2E)-4-hydroxy-2-nonenal via ω- and ω-1-oxidation stimulated by ketogenic diet.

Oxidative stress triggers the peroxidation of ω-6-polyunsaturated fatty acids to reactive lipid fragments, including (2E)-4-hydroxy-2-nonenal (HNE). We previously reported two parallel catabolic pathways of HNE. In this study, we report a novel metabolite that accumulates in rat liver perfused with HNE or 4-hydroxynonanoic acid (HNA), identified as 3-(5-oxotetrahydro-2-furanyl)propanoyl-CoA. In experiments using a combination of isotopic analysis and metabolomics studies, three catabolic pathways of HNE were delineated following HNE conversion to HNA. (i) HNA is ω-hydroxylated to 4,9-dihydroxynonanoic acid, which is subsequently oxidized to 4-hydroxynonanedioic acid. This is followed by the degradation of 4-hydroxynonanedioic acid via ß-oxidation originating from C-9 of HNA breaking down to 4-hydroxynonanedioyl-CoA, 4-hydroxyheptanedioyl-CoA, or its lactone, 2-hydroxyglutaryl-CoA, and 2-ketoglutaric acid entering the citric acid cycle. (ii) ω-1-hydroxylation of HNA leads to 4,8-dihydroxynonanoic acid (4,8-DHNA), which is subsequently catabolized via two parallel pathways we previously reported. In catabolic pathway A, 4,8-DHNA is catabolized to 4-phospho-8-hydroxynonanoyl-CoA, 3,8-dihydroxynonanoyl-CoA, 6-hydroxyheptanoyl-CoA, 4-hydroxypentanoyl-CoA, propionyl-CoA, and acetyl-CoA. (iii) The catabolic pathway B of 4,8-DHNA leads to 2,6-dihydroxyheptanoyl-CoA, 5-hydroxyhexanoyl-CoA, 3-hydroxybutyryl-CoA, and acetyl-CoA. Both in vivo and in vitro experiments showed that HNE can be catabolically disposed via ω- and ω-1-oxidation in rat liver and kidney, with little activity in brain and heart. Dietary experiments showed that ω- and ω-1-hydroxylation of HNA in rat liver were dramatically up-regulated by a ketogenic diet, which lowered HNE basal level. HET0016 inhibition and mRNA expression level suggested that the cytochrome P450 4A are main enzymes responsible for the NADPH-dependent ω- and ω-1-hydroxylation of HNA/HNE.