Serratia marcescens, as a Gram-negative opportunistic pathogen, is a rare cause of peritonitis and has worse clinical outcomes than Gram-positive peritonitis. In this case report, we describe a case of Serratia marcescens associated peritonitis that was successfully cured without catheter removal. A 40-year-old male patient with peritoneal dialysis who worked in the catering industry was admitted to the hospital for 16 hours after the discovery of cloudy peritoneal dialysate and abdominal pain. Ceftazidime and cefazolin sodium were immediately given intravenously as an empirical antibiotic regimen. After detecting Serratia marcescens in the peritoneal diasate culture, the treatment was switched to ceftazidime and levofloxacin. The routine examination of peritoneal dialysate showed a significant decrease in white blood cells, the peritoneal dialysate became clear, and the peritoneal dialysis catheter was retained. The patient was treated for 2 weeks and treated with oral antibiotics for 1 week. It is necessary to further strengthen the hygiene of work environment to prevent Serratia marcescens infection in peritoneal dialysis patients. We recommend that patients with Serratia marcescens associated peritonitis should be treated with a combination of antibiotics as early as possible empirically, and at the same time, the peritoneal dialysis fluid culture should be improved, and the antibiotic regimen should be timely adjusted according to the drug sensitivity results. For patients with clinical symptoms for more than 3 days, considering the strong virulence of Serratia marcescens, whether to use meropenem directly or not can provide a reference for clinical decision-making. Further clinical studies are needed to achieve more precise anti-infective treatment.

Caesarean section rate is increasing and postoperative wound infection is a major health-threatening complication after caesarean section (CS). The aim of this study was to evaluate the efficacy of Cefazolin at different time for post-caesarean delivery. The aim of this study was to compare the use of Cefazolin at different times on infections after CS. The time of antibiotic use in CS can be divided into two groups: before skin incision (SI) and after cord clamping (CC). In this study, 268 relevant articles were found in the database, and finally, 10 articles were analysed. This study included a total of 5256 cases of caesarean section. The data on wound infections, endometritis, urinary tract infections and fever were analysed. Perform an analysis of the data using RevMan 5.3. The results showed that cefazolin before SI reduced wound infection compared to after CC (odds ratio [OR], 0.51; 95% CI: 0.37-0.69; p < 0.0001). Cefazolin prophylactically used before SI reduce endometritis after CS compared to after CC (OR, 0.52; 95% CI: 0.35-0.77; p = 0.001). There was no significant difference in urinary tract infections after CS between cefazolin prophylactically used before SI and after CC (OR, 0.80; 95% CI: 0.50-11.28; p = 0.35). There was no significant difference in fever after CS between the prophylactic use of cefazolin before SI and after CC (OR, 0.60; 95% CI: 0.26-11.43; p = 0.225). Cefazolin before SI reduces wound infection and endometritis after CS.

BACKGROUND: A novel approach known as intraosseous regional administration (IORA) has emerged as a technique for delivering prophylactic antibiotics, and it results in higher tissue concentrations around the knee. It is hypothesized that IORA of cefazolin for antibiotic prophylaxis during total knee arthroplasty will result in sustained effective levels for a longer duration. The aim of the current study was to investigate temporal changes in peri-knee cefazolin blood concentrations after IORA of cefazolin.
METHODS: Twelve rabbits were randomly divided into two groups, with six rabbits in each group. In control group a single intravenous bolus injection of cefazolin (10 mL, 100 mg) was administered into the marginal ear vein. In experimental groupexperimental group the same dose of cefazolin was injected into the left tibial marrow cavity after tourniquet inflation at the base of the left thigh. Blood samples were collected periodically at different timepoints, and cefazolin concentrations were determined.
RESULTS: The intraosseous treatment resulted in significant differences in plasma cefazolin concentrations at all timepoints. Experimental group exhibited higher plasma cefazolin concentrations than control group.
CONCLUSIONS: Cefazolin in intraosseous regional prophylaxis exhibits effectiveness in intraoperative antibiotic prophylaxis by maintaining concentrations above the minimum inhibitory concentration for extended durations, rather than relying solely on high concentrations.

BACKGROUND: The selection of prophylactic antibiotics for preventing post-operative pulmonary infections in smoking patients undergoing video-assisted thoracoscopic lung surgery (VATLS) is not clear.
METHODS: In this retrospective cohort study, the outcomes of 572 smoking patients undergoing VATLS with prophylactic cefazolin/cefuroxime or other antibiotics were analyzed. Patients were classified as cefazolin/cefuroxime group and the control group. A 1:1 propensity score matching was also performed.
RESULTS: The primary outcome of the incidence of post-operative pulmonary infection did not differ significantly between the two groups (23.7% vs 30.5%, RR = 0.777, 95%CI 0.564 ~ 1.070 p = 0.113). Similarly, secondary outcomes including the incidence of post-operative fever, the white blood cell count and neutrophils on the 3rd day after the surgery, and time for blood routine test recovery were all found without significant difference between the two groups. In the multivariate logistic regression model, no association was found between prophylactic use of cefazolin/cefuroxime and post-operative pulmonary infections after controlling other possible confounding factors (OR = 0.685, 95%CI 0.441 ~ 1.065, p = 0.093).
CONCLUSIONS: Prophylactic use of cefazolin/cefuroxime was not associated with more adverse clinical outcomes among smoking populations undergoing VATLS when compared with broad-spectrum antibiotics and the two drugs are still feasible for peri-operative prophylactic use for smoking population before the surgery.

UNASSIGNED: Peritoneal dialysis-related peritonitis (PDRP) presents a significant challenge for nephrologists. Continuous intraperitoneal cefazolin and ceftazidime are recommended for the treatment of peritonitis. However, some pharmacokinetic studies have shown that doses of 15-20 mg/kg/d may not achieve sufficient therapeutic levels. In this study, we investigated the pharmacokinetics of ceftazidime and cefazolin in patients with continuous ambulatory peritoneal dialysis-related peritonitis and compared the pharmacokinetic characteristics between traditional and modified treatment groups.
UNASSIGNED: From February 2017 to December 2019, 42 PDRP patients (17 males, 25 females; mean age: 50.7 ± 12.1 years; mean body weight: 60.9 ± 11.8 kg) were recruited for the study, all participants were anuric. Twenty patients were enrolled in the traditional group and treated with cefazolin (1.0 g) and ceftazidime (1.0 g) via intraperitoneal administration once daily for 14 days. Twenty-two patients were enrolled in the modified group and received the same dose of antibiotics twice daily for the initial five days, followed by once daily for the subsequent nine days. Serum and dialysate samples were collected after days 1, 2, 3, 5, 7, 10, and 14 and analyzed via liquid chromatography-mass spectrometry.
UNASSIGNED: In the traditional group, the highest and lowest serum concentrations of ceftazidime were 35.9 and 21.7 µg/mL, respectively. The highest concentration of cefazolin was 54.6 µg/mL on day 5 and the lowest concentration was 30.4 µg/mL on day 1. In the modified group, the highest and lowest serum concentrations of ceftazidime were 102.2 and 54.8 µg/mL, respectively. The highest concentration of cefazolin was 141.7 µg/mL and the lowest concentration was 79.8 µg/mL. All antibiotic concentrations were above the minimum inhibitory concentration (MIC) level (8 µg/mL of ceftazidime and 2 µg/mL of cefazolin) throughout the treatment period. However, on day 1, the concentration of ceftazidime in the third bag of dialysate effluent from the traditional group fell below the MIC level. Despite remaining above the MIC, cefazolin concentration was consistently lower in the third bag of dialysate effluent from the traditional group throughout the treatment period.
UNASSIGNED: Intraperitoneal administration of cefazolin and ceftazidime at a dose of 1 g twice daily for 5 days and then once daily for the rest of the treatment period ensured adequate therapeutic levels of antibiotics for treating anuric PDRP patients.

Antibiotic resistance has become a serious threat to global public health and economic development. Rapid and accurate identification of a patient status for antimicrobial resistance (AMR) are urgently needed in clinical diagnosis. Here we describe the development of an assay method for activity fingerprinting of AMR β-lactamases using panels of 7 β-lactam antibiotics in 35 min. New Deli Metallo β-lactamase-1 (NDM-1) and penicillinase were demonstrated as two different classes of β-lactamases. The panel consisted of three classes of antibiotics, including: penicillins (penicillin G, piperacillin), cephalosporins (cefepime, ceftriaxone, cefazolin) and carbapenems (meropenem and imipenem). The assay employed a scheme combines the catalytic reaction of AMR β-lactamases on antibiotic substrates with a flow-injected thermometric biosensor that allows the direct detection of the heat generated from the enzymatic catalysis, and eliminates the need for custom substrates and multiple detection schemes. In order to differentiate classes of β-lactamases, characterization of the enzyme activity under different catalytic condition, such as, buffer composition, ion strength and pH were investigated. This assay could provide a tool for fast diagnosis of patient AMR status which makes possible for the future accurate treatment with selected antibiotics.

UNASSIGNED: Emerging data suggest that perioperative gut dysbiosis is prevalent and may be associated with postoperative neurocognitive disorders (PND). Antibiotics and probiotics are key factors influencing the microbiota. Many antibiotics have anti-microorganisms and direct anti-inflammatory properties, which may have cognitive repercussions. NLRP3 inflammasome activation has been reported to be involved with cognitive deficits. This study aimed to determine the effect and mechanism of probiotics on neurocognitive problems associated with perioperative gut dysbiosis by the NLRP3 pathway.
UNASSIGNED: In a randomized, controlled trial, adult male Kunming mice undergoing surgery were administered cefazolin, FOS + probiotics, CY-09, or a placebo in four distinct experimental cohorts. Fear conditioning (FC) tests evaluate learning and memory. Following FC tests to evaluate inflammatory response (IR) and the permeability of barrier systems, the hippocampus and colon were extracted, and feces were collected for 16 s rRNA.
UNASSIGNED: One week after surgery, surgery/anesthesia decreased the frozen behavior. Cefazolin attenuated this declination but aggravated postoperative freezing behavior 3 weeks after surgery. Probiotics ameliorated surgery/anesthesia-induced memory deficits and perioperative cefazolin-induced postoperative memory deficits 3 weeks after surgery. NLRP3, caspase-1, Interleukin-1β (IL-1β), and Interleukin-18 (IL-18) levels were increased 1 week after the hippocampus and colon surgery, which were attenuated by CY-09 and probiotics, respectively.
UNASSIGNED: Probiotics could correct dysbacteria and IR caused by surgery/anesthesia stress and cefazolin alone. These findings imply that probiotics are an efficient and effective way of maintaining the balance of gut microbiota, which may reduce NLRP3-related inflammation and alleviate PND.

Since bacteria in biofilms are inherently resistant to antibiotics and biofilm-associated infections pose a serious threat to global public health, new therapeutic agents and schemes are urgently needed to meet clinical requirements. Here two quaternary ammonium-functionalized biphen[n]arenes (WBPn, n=4, 5) were designed and synthesized with excellent anti-biofilm potency. Not only could they inhibit the assembly of biofilms, but also eradicate intractable mature biofilms formed by Gram-positive S. aureus and Gram-negative E. coli bacterial strains. Moreover, they could strongly complex a conventional antibiotic, cefazolin sodium (CFZ) with complex stability constants of (7.41±0.29)×104  M-1 for CFZ/WBP4 and (4.98±0.49)×103  M-1 for CFZ/WBP5. Combination of CFZ by WBP4 and WBP5 synergistically enhanced biofilm eradication performance in vitro and statistically improved healing efficacy on E. coli-infected mice models, providing a novel supramolecular strategy for combating biofilm-associated infections.

Enterobacter cloacae complex (ECC) is a common opportunistic pathogen and is responsible for causing various infections in humans. Owing to its inducible chromosomal AmpC β-lactamase (AmpC), ECC is inherently resistant to the 1st- and 2nd- generation cephalosporins. However, whether β-lactams antibiotics enhance ECC resistance remains unclear.
In this study, we found that subinhibitory concentrations (SICs) of cefazolin (CFZ) and imipenem (IMP) can advance the expression of AmpC and enhance its resistance towards β-lactams through NagZ in Enterobacter cloacae (EC). Further, AmpC manifested a substantial upregulation in EC in response to SICs of CFZ and IMP. In nagZ knockout EC (ΔnagZ), the resistance to β-lactam antibiotics was rather weakened and the effect of CFZ and IMP on AmpC induction was completely abrogated. NagZ ectopic expression can rescue the induction effects of CFZ and IMP on AmpC and increase ΔnagZ resistance. More importantly, CFZ and IMP have the potential to induce the expression of AmpR\'s target genes in a NagZ-dependent manner.
Our findings suggest that NagZ is a critical determinant for CFZ and IMP to promote AmpC expression and resistance and that CFZ and IMP should be used with caution since they may aggravate ECC resistance. At the same time, this study further improves our understanding of resistance mechanisms in ECC.

The environmental pollution and human health risks caused by anti-infective residual drugs in the environment have attracted much attention. More convenient and effective detection methods to achieve the rapid and high sensitivity detection for such pollutants are required. In this work, a novel surface-enhanced Raman scattering (SERS) strategy based on vortex aggregation of AgNPs was proposed for the detection of anti-infective drugs in environmental water. The method enhanced the Raman signal of the targets by 2-7.4 times. The mechanism of aggregation enhancement effect under the low-frequency oscillation procedure which significantly enhanced the SERS signal of targets molecular on the aggregated AgNPs was revealed by UV-vis and ICP-MS methods. Three drugs of cefazolin sodium, pefloxacin, and chloroquine phosphate were determined. The detect limits were 3.97 × 10-9 mol/L, 2.42 × 10-10 mol/L, and 7.34 × 10-9 mol/L for cefazolin sodium, pefloxacin, and chloroquine phosphate, respectively. The quantitative relationships were obtained in a wide linear range of 4-5 orders as well as good accuracy and stability with the recoveries of 84.0%-97.1% and the relative standard deviations (RSDs) less than 4.6% for spiked in actual water samples. This method also had excellent repeatability and stability, which have potential application for rapid detection of trace pollutants in water environment.