Population pharmacokinetics and pharmacodynamic target attainment analysis of cefazolin using total and unbound serum concentration in patients with prostatectomy or nephrectomy.

The aim of this study was to analyze the population pharmacokinetics of total and unbound concentrations of prophylactic cefazolin (CFZ) in patients with prostatectomy or nephrectomy. We also aimed to calculate a pharmacodynamics target unbound concentration that exceeded the minimum inhibitory concentration (MIC), to design an effective dosing regimen. Briefly, 614 total concentration and 610 unbound concentration samples from 152 individuals were evaluated, using a nonlinear mixed-effects model. The obtained pharmacodynamics index target value reflected the probability of maintaining CFZ unbound trough concentrations exceeding MIC90, 0.5 mg/L, and MIC50, and 1.0 mg/L, to account for methicillin-susceptible Staphylococcus aureus (MSSA) or Escherichia coli. Population pharmacokinetics were estimated using a two-compartment model with nonlinear protein binding. Unbound systemic clearance (CL) was significantly associated with creatinine clearance, while the maximum protein-binding constant was significantly associated with albumin levels. The probability of achieving an unbound concentration exceeding the MIC50 for E. coli or MIC90 for MSSA in a patient with normal renal function following a 1 g CFZ infusion over 15 min was above 90% at 3 h after the initial dose. Our findings indicated that population pharmacokinetic parameters are useful for determining unbound CFZ pharmacokinetics and evaluating intraoperative CFZ redosing intervals.

Plasma and tissue concentrations of 2 g prophylactic cefazolin prior to lower extremity surgery.

Surgical site infections (SSIs) are among the most clinically relevant complications and the use of prophylactic cefazolin is common practice. However, the knowledge about the pharmacological aspects of prophylactic cefazolin in the lower extremities remains limited. In this prospective cohort, a sub-study of the WIFI-2 randomized controlled trial, adults between 18 and 75 years of age who were scheduled for implant removal below the level of the knee and randomized for cefazolin, was included. A maximum of two venous plasma, target-site plasma, and target-site tissue samples were taken during surgery. The primary outcomes were the cefazolin concentrations in venous plasma, target-site plasma, and target-site tissue. A total of 27 patients [median (interquartile range) age, 42 (29-59) years; 17 (63%) male] with 138 samples were included in the study. A minimum of 6 weeks follow-up was available for all patients. The mean (SD) venous plasma, target-site plasma, and target-site tissue concentrations were 36 (13) µg/mL, 29 (13) µg/mL, and 28 (13) µg/g, respectively, and the cefazolin concentrations between the different locations of surgery did not differ significantly in both target-site plasma and target-site tissue (P = 0.822 and P = 0.840). In conclusion, 2 g of prophylactic cefazolin demonstrates adequacy in maintaining coverage for a duration of at least 80 minutes of surgery below the level of the knee, significantly surpassing the MIC90 required to combat the most prevalent microorganisms. This study represents the first of its kind to assess cefazolin concentrations in the lower extremities by examining both plasma and tissue samples in this magnitude.

Interspecies variability in protein binding of antibiotics basis for translational PK/PD studies-a case study using cefazolin.

For antimicrobial agents in particular, plasma protein binding (PPB) plays a pivotal role in deciphering key properties of drug candidates. Animal models are generally used in the preclinical development of new drugs to predict their effects in humans using translational pharmacokinetics/pharmacodynamics (PK/PD). Thus, we compared the protein binding (PB) of cefazolin as well as bacterial growth under various conditions in vitro. The PB extent of cefazolin was studied in human, bovine, and rat plasmas at different antibiotic concentrations in buffer and media containing 20-70% plasma or pure plasma using ultrafiltration (UF) and equilibrium dialysis (ED). Moreover, bacterial growth and time-kill assays were performed in Mueller Hinton Broth (MHB) containing various plasma percentages. The pattern for cefazolin binding to plasma proteins was found to be similar for both UF and ED. There was a significant decrease in cefazolin binding to bovine plasma compared to human plasma, whereas the pattern in rat plasma was more consistent with that in human plasma. Our growth curve analysis revealed considerable growth inhibition of Escherichia coli at 70% bovine or rat plasma compared with 70% human plasma or pure MHB. As expected, our experiments with cefazolin at low concentrations showed that E. coli grew slightly better in 20% human and rat plasma compared to MHB, most probably due to cefazolin binding to proteins in the plasma. Based on the example of cefazolin, our study highlights the interspecies differences of PB with potential impact on PK/PD. These findings should be considered before preclinical PK/PD data can be extrapolated to human patients.

Cefazolin as a predictor of urinary cephalosporin activity in indicated Enterobacterales.

Traditionally, cephalothin susceptibility results were used to predict the susceptibility of additional cephalosporins; however, in 2013-2014, the Clinical and Laboratory Standards Institute (CLSI) revisited this practice and determined that cefazolin is a more accurate proxy than cephalothin for uncomplicated urinary tract infections (uUTIs). Therefore, a cefazolin surrogacy breakpoint was established to predict the susceptibility of seven oral cephalosporins for Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis in the context of uUTIs. Clinical microbiology laboratories face several operational challenges when implementing the cefazolin surrogacy breakpoint, which may lead to confusion for the best path forward. Here, we review the historical context and data behind the surrogacy breakpoints, review PK/PD profiles for oral cephalosporins, discuss challenges in deploying the breakpoint, and highlight the limited clinical outcome data in this space.

Metronidazole and cefazolin vs cefazolin alone for surgical site infection prophylaxis in gynecologic surgery at a comprehensive cancer center.

BACKGROUND: Surgical site infection is one of the most common complications of gynecologic cancer surgery. Current guidelines recommend the administration of cefazolin preoperatively to reduce surgical site infection rates for patients undergoing clean-contaminated surgeries such as hysterectomy. OBJECTIVE: To evaluate the impact of a quality improvement project adding metronidazole to cefazolin for antibiotic prophylaxis on surgical site infection rate for women undergoing gynecologic surgery at a comprehensive cancer center. STUDY DESIGN: This retrospective, single-center cohort study included patients who underwent surgery in the gynecologic oncology department from May 2017 to June 2023. Patients with penicillin allergies and those undergoing concomitant bowel resections and/or joint cases were excluded. The preintervention group patients had surgery from May 2017 to April 2022, and the postintervention group patients had surgery from April 2022 to June 2023. The primary outcome was a 30-day surgical site infection rate. Sensitivity analyses were performed to compare surgical site infection rates on the basis of actual antibiotics received and for those who had a hysterectomy. Factors independently associated with surgical site infection were identified using a multivariable logistic regression model adjusting for confounding variables. RESULTS: Of 3343 patients, 2572 (76.9%) and 771 (23.1%) were in the pre-post intervention groups, respectively. Most patients (74.7%) had a hysterectomy performed. Thirty-four percent of cases were for nononcologic (benign) indications. Preintervention patients were more likely to receive appropriate preoperative antibiotics (95.6% vs 90.7%; P<.001). The overall surgical site infection rate before the intervention was 4.7% compared with 2.6% after (P=.010). The surgical site infection rate for all patients who underwent hysterectomy was 4.9% (preintervention) vs 2.8% (postintervention) (P=.036); a similar trend was seen for benign cases (4.4% vs 2.4%; P=.159). On multivariable analysis, the odds ratio for surgical site infection was 0.49 (95% confidence interval, 0.38-0.63) for the postintervention compared with the preintervention group (P<.001). In a sensitivity analysis (n=3087), the surgical site infection rate was 4.5% for those who received cefazolin alone compared with 2.3% for those who received cefazolin plus metronidazole, with significantly decreased odds of surgical site infection for the cefazolin plus metronidazole group (adjusted odds ratio, 0.40 [95% confidence interval, 0.30-0.53]; P<.001). Among only those who had a hysterectomy performed, the odds of surgical site infection were significantly reduced for those in the postintervention group (adjusted odds ratio, 0.63 [95% confidence interval, 0.47-0.86]; P=.003). CONCLUSION: The addition of metronidazole to cefazolin before gynecologic surgery decreased the surgical site infection rate by half, even after accounting for other known predictors of surgical site infection and differences in practice patterns over time. Providers should consider this combination regimen in women undergoing gynecologic surgery, especially for cases involving hysterectomy.

Effectiveness and safety of cefazolin versus cloxacillin in endocarditis due to methicillin-susceptible Staphylococcus spp.: a multicenter propensity weighted cohort study.

PURPOSE: To compare the effectiveness and safety of cefazolin versus cloxacillin for the treatment of infective endocarditis (IE) due to methicillin-sensitive Staphylococci (MSS). METHODS: Data were retrospectively collected on patients treated for a definite MSS endocarditis who received cefazolin or cloxacillin for at least 10 consecutive days in six French hospitals between January-1 2014 and December-31 2020. The primary endpoint was treatment failure defined as a composite of death within 90 days of starting antibiotherapy, or embolic event during antibiotherapy, or relapse of IE within 90 days of stopping antibiotherapy. We used Cox regression adjusted for the inverse probability of treatment weighting of receiving cefazolin. RESULTS: 192 patients were included (median age 67.8 years). IE was caused by S.aureus in 175 (91.1%) and by coagulase-negative staphylococci in 17 (8.9%). Ninety-four patients (48.9%) received cefazolin, and 98 (51%) received cloxacillin. 34 patients (34.7%) with cefazolin and 26 (27.7%) with cloxacillin met the composite primary endpoint, with no significant differences between groups (adjusted HR = 1.13, 95% CI 0.63 to 2.03). There were no significant differences in secondary efficacy endpoints or biological safety events. CONCLUSION: The effectiveness of cefazolin did not significantly differ from cloxacillin for the treatment of MSS endocarditis.

Flucloxacillin and cefazolin for treatment of Staphylococcus aureus bloodstream infection.

PURPOSE: Antistaphylococcal penicillins and cefazolin have been used as first line therapy in Methicillin-susceptible Staphylococcus aureus bloodstream infection. While efficacy of both regimens seems to be similar, the compounds may differ with regard to tolerability. This study aims to describe the clinical use of cefazolin and flucloxacillin, focussing on discontinuation or change of anti-infective agent due to adverse events. METHODS: This observational prospective study was conducted at two German tertiary care centres with an internal recommendation of flucloxacillin for MSSA-BSI in one, and of cefazolin in the other centre. Adverse events were registered weekly under treatment and at a 90-day follow-up. Descriptive analysis was complemented by a propensity score analysis comparing adverse events (stratified rank-based test applied to the sum of Common Terminology Criteria for adverse events ratings per patient). RESULTS: Of 71 patients included, therapy was initiated with flucloxacillin in 56 (79%), and with cefazolin in 15 (21%). The propensity score analysis indicates a statistically significant difference concerning the severity of adverse events between the treatment groups in favour of cefazolin (p = 0.019). Adverse events led to discontinuation of flucloxacillin in 7 individuals (13% of all patients receiving flucloxacillin). Clinical outcome was not different among treatment groups. CONCLUSION: Using cefazolin rather than flucloxacillin as a first line agent for treatment of MSSA-BSI is supported by these clinical data.

Prospective assessment of the frequency of and risk factors for bleeding events in patients treated with cefazolin.

PURPOSE: Major bleedings have been described with cefazolin. The objective was to determine the frequency of bleeding events in cefazolin-treated patients and to identify risk factors for these complications. METHODS: Monocenter prospective observational study of all consecutive cefazolin-treated patients. Patients benefited from a daily clinical assessment of bleedings and a twice-a-week blood sampling including hemostasis. Bleedings were classified according to the International Society on Thrombosis and Hemostasis classification: major, clinically relevant non-major bleedings (CRNMB) and minor bleedings. RESULTS: From September 2019 to July 2020, 120 patients were included, with a mean age of 59.4 (± 20.7) years; 70% of them (84/120) were men. At least 1 CRNMB or major bleeding were observed in 10% of the patients (12/120). Compared to patients with no or minor bleeding, patients with CRNMB or major bleeding were, upon start of cefazolin, more frequently hospitalized in an intensive care unit (7/12, 58.3%, vs. 12/108, 11.1%, P < 0.001, respectively) and receiving vitamin K antagonists (4/12, 33.3%, vs. 8/108, 7.4%, P = 0.019, respectively). After multivariate analysis, patients receiving vitamin K antagonists the day prior bleeding and/or treated for endocarditis were factors associated with an increased risk of CRNMB or major bleeding (odd ratio 1.36, confidence interval 95%, 1.06-1.76, P = 0.020 and 1.30, 1.06-1.61, P = 0.015, respectively). CONCLUSIONS: Bleeding events associated with cefazolin treatment are frequent. Close clinical monitoring should be performed for patients treated for endocarditis and/or receiving vitamin K antagonists. Hemostasis work-up could be restricted to these patients.

Cephalosporin Allergy: Updates on Diagnostic Testing.

PURPOSE OF REVIEW: Cephalosporins are one of the most prescribed antibiotics worldwide and are implicated in a wide range of hypersensitivity reactions (HSR). This review summarizes recent updates in cephalosporin hypersensitivity with a focus on diagnostic testing. RECENT FINDINGS: Reported testing strategies to evaluate different immediate and delayed cephalosporin HSR have included skin testing, in vitro testing, and diagnostic drug challenges. However, the diagnostic performance of in vivo and in vitro tests remains unclear across different hypersensitivity endotypes; adequately powered studies investigating the true positive and negative predictive value of these diagnostic modalities are needed using the reference standard of drug challenges to define cephalosporin hypersensitivity. Refinement of diagnostic testing should be guided by growth in our understanding of cephalosporin antigenic determinants. This growth will be crucial in driving further clarification of cross-reactivity between cephalosporins, and potentially delineating streamlined evaluation processes resulting in reduced unnecessary antibiotic avoidance.

Epidemiology of perioperative anaphylaxis in France in 2017-2018: the 11th GERAP survey.

BACKGROUND: Perioperative anaphylaxis is rare but is associated with significant morbidity. This complication has been well described in France by the GERAP (Groupe d'Etude des Réactions Anaphylactiques Périopératoires), a network focused on its study. The epidemiology of perioperative anaphylaxis is evolving, influenced by environmental factors and clinical practice. The aim of this study was to update the epidemiology of perioperative anaphylaxis in France. METHODS: This multicentre retrospective study was performed in 26 allergy clinics of the GERAP network in 2017-8. RESULTS: There were 765 patients with perioperative anaphylaxis included. Most cases were severe, with 428 (56%) reactions graded as 3 or 4 according to the Ring and Messmer classification. Skin test results were available for 676 patients, with a culprit agent identified in 471 cases (70%). Neuromuscular blocking agents were the main cause of perioperative anaphylaxis (n=281; 60%), followed by antibiotics (n=118; 25%) and patent blue dye (n=11; 2%). Cefazolin was the main antibiotic responsible for perioperative anaphylaxis (52% of antibiotic-related reactions). Suxamethonium and rocuronium were the main neuromuscular blocking agents responsible for perioperative anaphylaxis with 7.1 (6.1-8.4) and 5.6 (4.2-7.4) reactions per 100,000 vials sold, respectively, whereas cefazolin-related cases were estimated at 0.7 (0.5-0.9) reactions per 100,000 vials sold. CONCLUSIONS: Our results confirm that most commonly identified triggering agents remain neuromuscular blocking agents. Reactions to antibiotics, particularly cefazolin, are becoming increasingly frequent. The origin of sensitisation to cefazolin is unknown, as no cross-sensitisation has been described, and it should be the subject of further study. Perioperative anaphylaxis should be followed over the years and understood given the changing triggers. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT04654923).

The Role of Preoperative Antibiotics in Surgical Site Infection (SSI) Rate after Class I/Clean Gynaecologic Surgery at an Academic Safety Net Hospital.

OBJECTIVES: Examine whether preoperative antibiotics in class I/clean abdominal gynaecologic surgery decrease the incidence of surgical site infections (SSI). METHODS: Retrospective cohort study at academic safety net hospital of patients undergoing class I laparoscopic or open gynaecologic surgery between November 2013 and September 2017. Performance improvement initiative to administer preoperative antibiotics to all surgical patients starting July 2016. RESULTS: In total, 510 patients were included: 283 in the antibiotic group and 227 in the no-antibiotic group. PRIMARY OUTCOME: incidence of SSI. Baseline characteristics were similar between groups once balanced by propensity score method. In unweighted analysis, incidence of SSI decreased from 9.3% (21/227) in the no-antibiotics group to 4.9% (14/283) in antibiotics group, but this was not statistically significant (odds ratio (OR) 0.51 CI 0.25-1.03, P = 0.0598). Following of inverse probability of treatment weighting adjustments in weighted analysis, incidence of SSI was found to be significantly lower in patients who received antibiotics compared to patients who did not receive antibiotics across entry types (4.6% vs. 9.8%, OR 0.45; CI 0.22-0.90, P = 0.023). Weighted analysis demonstrated in the exploratory laparotomy group patients who received antibiotics had a lower incidence of SSI compared to patients who did not receive antibiotics (5.1% vs. 18.7%, OR 0.23; CI 0.08-0.68, P = 0.008). In the laparoscopy group, there was no difference between groups (4.4% vs. 5.4%, OR 0.81; CI 0.3-2.16, P = 0.675). CONCLUSIONS: There is limited literature on SSI prevention/preoperative antibiotic use in class I gynaecologic surgeries. This study demonstrates antibiotics in class I procedures decrease SSI rates, specifically in open procedures. There was a lack of demonstrated benefit in laparoscopy.

Prolonged efficacy of cefazolin in intraosseous regional prophylaxis for total knee arthroplasty: a rabbit model study.

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.

FeS2 nanosheets-luminol-O2 chemiluminescence method for determination of venlafaxine hydrochloride, imipramine hydrochloride, and cefazolin sodium.

This study introduces a novel chemiluminescence (CL) approach utilizing FeS2 nanosheets (NSs) catalyzed luminol-O2 CL reaction for the measurement of three pharmaceuticals, namely venlafaxine hydrochloride (VFX), imipramine hydrochloride (IPM), and cefazolin sodium (CEF). The CL method involved the phenomenon of quenching induced by the pharmaceuticals in the CL reaction. To achieve the most quenching efficacy of the pharmaceuticals in the CL reaction, the concentrations of reactants comprising luminol, NaOH, and FeS2 NSs were optimized accordingly. The calibration curves demonstrated exceptional linearity within the concentration range spanning from 4.00 × 10-7 to 1.00 × 10-3 mol L-1, 1.00 × 10-7 to 1.00 × 10-4 mol L-1, and 4.00 × 10-6 to 2.00 × 10-4 mol L-1 with detection limits (3σ) of 3.54 × 10-7, 1.08 × 10-8, and 2.63 × 10-6 mol L-1 for VFX, IPM, and CEF, respectively. This study synthesized FeS2 NSs using a facile hydrothermal approach, and then the synthesized FeS2 NSs were subjected to a comprehensive characterization using a range of spectroscopic methods. The proposed CL method was effective in measuring the aforementioned pharmaceuticals in pharmaceutical formulations as well as different water samples. The mechanism of the CL system has been elucidated.

Comparison of the effect between cefazolin/cefuroxime and broad-spectrum antibiotics in preventing post-operative pulmonary infections for smoking patients receiving video-assisted thoracoscopic lung surgery: a propensity score-matched retrospective cohort study.

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.

After primary shoulder arthroplasty appropriate vancomycin antibiotic prophylaxis does not lead to increased infectious complications when compared to cefazolin.

BACKGROUND: In primary shoulder arthroplasty (SA), intravenous (IV) cefazolin has demonstrated lower rates of infectious complications when compared to IV vancomycin. However, previous analyses included SA cohorts with both complete and incomplete vancomycin administration. Therefore, it is currently unclear whether cefazolin still maintains a prophylactic advantage to vancomycin when it is appropriately indicated and sufficiently administered at the time of surgical incision. This study evaluated the comparative efficacy of cefazolin and complete vancomycin administration for surgical prophylaxis in primary shoulder arthroplasty with respect to infectious complications. METHODS: A retrospective cohort study was conducted utilizing a single institution total joint registry database, where all primary SA types (hemiarthroplasty, anatomic total shoulder arthroplasty, and reverse shoulder arthroplasty) performed between 2000 to 2019 for elective and trauma indications using IV cefazolin or complete vancomycin administration as the primary antibiotic prophylaxis were identified. Vancomycin was primarily indicated for patients with a severe self-reported penicillin or cephalosporin allergy and/or MRSA colonization. Complete administration was defined as at least 30 minutes of antibiotic infusion prior to incision. All included SA had at least 2 years of clinical follow-up. Multivariable Cox proportional hazard regression was used to evaluate all-cause infectious complications including survival free of prosthetic joint infection (PJI). RESULTS: The final cohort included 7177 primary SA, 6879 (95.8%) received IV cefazolin and 298 (4.2%) received complete vancomycin administration. Infectious complications occurred in 120 (1.7%) SA leading to 81 (1.1%) infectious reoperations. Of the infectious complications, 41 (0.6%) were superficial infections and 79 were (1.1%) PJIs. When categorized by administered antibiotics, there were no differences in rates of all infectious complications (1.6% vs. 2.3%; P = .352), superficial complications (0.5% vs. 1.3%; P = .071), PJI (1.1% vs. 1.0%; P = .874), or infectious reoperations (1.1% vs. 1.0%; P = .839). On multivariable analyses, complete vancomycin infusion demonstrated no difference in rates of infectious complications compared to cefazolin administration (hazard ratio [HR], 1.50 [95% confidence interval (CI), 0.70 to 3.25]; P = .297), even when other independent predictors of PJI (male sex, prior surgery, and Methicillin-resistant Staphylococcus aureus colonization) were considered. CONCLUSIONS: In comparison to cefazolin, complete administration of vancomycin (infusion to incision time greater than 30 minutes) as the primary prophylactic agent does not adversely increase the rates of infectious complications and PJI. Prophylaxis protocols should promote appropriate indications for the use of cefazolin or vancomycin, and when necessary, ensure complete administration of vancomycin to mitigate additional infectious risks after primary SA.

Non-cefazolin antibiotic prophylaxis is associated with higher rates of elbow periprosthetic joint infection.

BACKGROUND: Periprosthetic joint infection (PJI) is a common source of failure following elbow arthroplasty. Perioperative prophylactic antibiotics are considered standard of care. However, there are no data regarding the comparative efficacy of various antibiotics in the prevention of PJI for elbow arthroplasty. Previous studies in shoulder, hip, and knee arthroplasty have demonstrated higher rates of PJI with administration of non-cefazolin antibiotics. The elbow has higher rates of PJI than other joints. Therefore, this study evaluated whether perioperative antibiotic choice affects rates of PJI in elbow arthroplasty. MATERIALS AND METHODS: A single-institution, prospectively collected total joint registry database was queried to identify patients who underwent primary elbow arthroplasty between 2003 and 2021. Elbows with known infection prior to arthroplasty (25) and procedures with incomplete perioperative antibiotic data (7) were excluded, for a final sample size of 603 total elbow arthroplasties and 19 distal humerus hemiarthroplasties. Cefazolin was administered in 561 elbows (90%) and non-cefazolin antibiotics including vancomycin (32 elbows, 5%), clindamycin (27 elbows, 4%), and piperacillin/tazobactam (2 elbows, 0.3%) were administered in the remaining 61 elbows (10%). Univariate and multivariate analyses were conducted to determine the association between the antibiotic administered and the development of PJI. Infection-free survivorship was estimated using the Kaplan-Meier method. RESULTS: Deep infection occurred in 47 elbows (7.5%), and 16 elbows (2.5%) were diagnosed with superficial infections. Univariate analysis demonstrated that patients receiving non-cefazolin alternatives were at significantly higher risk for any infection (hazard ratio [HR] 2.6, 95% confidence interval [CI] 1.4-5.0; P < .01) and deep infection (HR 2.7, 95% CI 1.3-5.5; P < .01) compared with cefazolin administration. Multivariable analysis, controlling for several independent predictors of PJI (tobacco use, male sex, surgical indication other than osteoarthritis, and American Society of Anesthesiologists score), showed that non-cefazolin administration had a higher risk for any infection (HR 2.8, 95% CI 1.4-5.3; P < .01) and deep infection (HR 2.9, 95% CI 1.3-6.3; P < .01). Survivorship free of infection was significantly higher at all time points for the cefazolin cohort. DISCUSSION: In primary elbow arthroplasty, cefazolin administration was associated with significantly lower rates of PJI compared to non-cefazolin antibiotics, even in patients with a greater number of prior surgeries, which is known to increase the risk of PJI. For patients with penicillin or cephalosporin allergies, preoperative allergy testing or a cefazolin test dose should be considered before administering non-cefazolin alternatives.

Ciprofloxacin-, Cefazolin-, and Methicilin-Soaked Graphene Paper as an Antibacterial Medium Suppressing Cell Growth.

This paper presents the results of research on the impact of graphene paper on selected bacterial strains. Graphene oxide, from which graphene paper is made, has mainly bacteriostatic properties. Therefore, the main goal of this research was to determine the possibility of using graphene paper as a carrier of a medicinal substance. Studies of the degree of bacterial inhibition were performed on Staphylococcus aureus and Pseudomonas aeruginosa strains. Graphene paper was analyzed not only in the state of delivery but also after the incorporation of the antibiotics ciprofloxacin, cefazolin, and methicillin into its structures. In addition, Fourier-Transform Infrared Spectroscopy, contact angle, and microscopic analysis of bacteria on the surface of the examined graphene paper samples were also performed. Studies have shown that graphene paper with built-in ciprofloxacin had a bactericidal effect on the strains of Staphylococcus aureus and Pseudomonas aeruginosa. In contrast, methicillin, as well as cefazolin, deposited on graphene paper acted mainly locally. Studies have shown that graphene paper can be used as a carrier of selected medicinal substances.

Corrosion Inhibition of Expired Cefazolin Drug on Copper Metal in Dilute Hydrochloric Acid Solution: Practical and Theoretical Approaches.

In this work, we studied the corrosion of Cu metal in 0.5 mol L-1 HCl and the inhibition effect of the expired Cefazolin drug. The inhibition efficiency (IE) of Cefazolin varied according to its concentration in solution. As the Cefazolin concentration increased to 300 ppm, the IE increased to 87% at 298 K and decreased to 78% as the temperature increased to 318 K. The expired drug functioned as a mixed-type inhibitor. The adsorption of the drug on the copper surface followed Temkin's adsorption model. The magnitudes of the standard free energy change (ΔGoads) and adsorption equilibrium constant (Kads) indicated the spontaneous nature and exothermicity of the adsorption process. Energy dispersive X-ray (EDX) and scanning electron microscopy (SEM) techniques showed that the drug molecules were strongly attached to the Cu surface. The electrochemical frequency modulation (EFM), potentiodynamic polarization (PP), and electrochemical impedance spectroscopy (EIS) results were in good agreement with the results of the weight loss (WL) method. The density functional tight-binding (DFTB) and Monte Carlo (MC) simulation results indicated that the expired drug bound to the copper surface through the lone pair of electrons of the heteroatoms as well as the π-electrons of the tetrazole ring. The adsorption energy between the drug and copper metal was -459.38 kJ mol-1.

Effect of prophylactic use of cefazolin in caesarean section on postoperative infection: A meta-analysis.

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.

Antibiotic Myths for the Infectious Diseases Clinician.

Antimicrobials are commonly prescribed and often misunderstood. With more than 50% of hospitalized patients receiving an antimicrobial agent at any point in time, judicious and optimal use of these drugs is paramount to advancing patient care. This narrative will focus on myths relevant to nuanced consultation from infectious diseases specialists, particularly surrounding specific considerations for a variety of antibiotics.