Antibiotic Prophylaxis

Hepatic and pancreatic surgeries are associated with a high risk of surgical site infections, particularly in patients with preoperative biliary drainage, which is frequently associated with bacterial colonization of bile. In this context, perioperative antibiotic prophylaxis is essential, and recent guidelines recommend the use of piperacillin/tazobactam in selected high-risk patients. However, piperacillin, like other β-lactam antibiotics, exhibits pharmacokinetic variability that may be exacerbated during major surgery due to factors such as fluid shifts, hypoalbuminemia, and changes in volume of distribution. These alterations may result in suboptimal antibiotic exposure during the perioperative period, potentially compromising prophylactic efficacy. Despite these concerns, standard dosing regimens remain unchanged across different types of major abdominal surgery, including hepatic and pancreatic procedures, which differ significantly in terms of duration, physiological impact, and intraoperative management. The PROPHTAZ study is a prospective, single-center observational pharmacokinetic study designed to evaluate whether standard perioperative administration of piperacillin/tazobactam achieves predefined pharmacokinetic/pharmacodynamic (PK/PD) targets in patients undergoing hepatic or pancreatic surgery. The primary objective is to determine the proportion of patients achieving adequate PK/PD exposure during surgery. Secondary objectives include describing perioperative plasma concentrations, assessing pharmacokinetic variability, identifying factors associated with target non-attainment, and comparing outcomes between surgical subgroups. This study aims to provide clinically relevant data to assess the adequacy of current prophylactic dosing strategies and to support potential optimization of antibiotic administration in high-risk surgical patients.

This randomized, double-blind, placebo-controlled clinical trial aims to evaluate whether single-dose amoxicillin prophylaxis administered prior to simple tooth extraction reduces postoperative infection rates in immunosuppressed patients with autoimmune rheumatic diseases (ARDs). Although antibiotic prophylaxis is not recommended for healthy individuals undergoing simple extractions, immunosuppressed ARD patients frequently receive antibiotics despite limited evidence supporting this practice. Secondary objectives include assessing infection severity, postoperative complications, and the impact of ARD diagnosis and immunosuppressive treatment on infection risk.

Anesthesia and surgical guidelines recommend the administration of a surgical antibiotic prophylaxis for patients undergoing "clean" surgery. The prescribed antibiotic should target the bacteria most commonly found in surgical site infections (SSIs) and the duration of administration should not exceed 24 hours to minimize the ecological risk of bacterial resistance emergence. Guidelines provide a framework for the administration of surgical antibiotic prophylaxis but their effectiveness is regularly re-evaluated by measuring the rates of SSIs and the microorganisms responsible for infectious complications after surgery. The majority of interventions required the use of first or second generation cephalosporins as surgical antibiotic prophylaxis. For patients with allergy to beta-lactams, clindamycin and vancomycin are proposed as alternatives. In the patients with methicillin-resistant S. aureus (MRSA) colonization or if those at risk of developing MRSA-associated SSI (hospital ecology, previous antibiotic treatment), only vancomycin is recommended. Vancomycin pharmacokinetics and pharmacodynamics is complex and its tissue absorption varies according to the level of tissue inflammation. This is a difficult molecule to handle, exclusively administered via intravenous route. Linezolid is a synthetic antibiotic from the oxazolidinone class. By binding to the rRNA on the 30S and 50S ribosomal subunits, it inhibits the bacterial synthesis. It is therefore a bacteriostatic antibiotic approved for the treatment of both methicillin susceptible S. aureus (MSSA) and MRSA infections. It also covers a broad spectrum of Gram positive bacteria. Its pharmacokinetics allows rapid intravenous infusion, with rapid penetration into bone and soft tissue of the surgical site during hip surgery. A large Cochrane meta-analysis reported that linezolid was superior to vancomycin in skin infections, including MRSA infections, albeit with low quality evidence. We therefore hypothesized that linezolid can be used instead of vancomycin for beta-lactam allergic patients and patients at risk of MRSA-associated SSI in general surgery.

Tooth extraction sites often require alveolar bone grafting to preserve ridge dimensions and improve conditions for future implant placement. Although systemic antibiotic prophylaxis is commonly prescribed after grafting procedures, there is limited evidence supporting its necessity in healthy patients undergoing intraoral bone grafting. This randomized, double-blind, placebo-controlled clinical trial aims to compare the effects of prophylactic amoxicillin versus placebo on postoperative outcomes in alveolar bone graft procedures using Plenum® Oss HP biomaterial, a synthetic biphasic bioceramic composed of hydroxyapatite and beta-tricalcium phosphate (HA/β-TCP; 70:30 ratio). Participants will be randomly assigned to receive either amoxicillin 500 mg every 8 hours for 7 days or a matching placebo. Clinical parameters, postoperative complications, and patient-reported outcomes will be assessed. The study seeks to determine whether antibiotic prophylaxis provides measurable clinical benefits or whether placebo yields comparable results, contributing to more rational antibiotic use and supporting antimicrobial stewardship in oral surgery.

The goal of this clinical trial is to learn whether adding azithromycin to the standard antibiotic treatment (ampicillin) improves newborn outcomes in women with preterm premature rupture of membranes (PPROM) between 34.0 and 36.6 weeks of pregnancy. The main question it aims to answer is: Does the combination of ampicillin and azithromycin lower the risk of serious neonatal health problems compared to ampicillin alone? Researchers will compare two antibiotic regimens: Ampicillin alone, which is the current standard care Ampicillin with azithromycin, a broader regimen that may better prevent infections and prolong pregnancy Participants will: Receive one of the two antibiotic treatments during hospitalization. Be monitored until delivery for signs of infection and labor All participants will stay in the hospital until delivery. The study also looks at how the antibiotic choice may affect the time between membrane rupture and delivery, maternal infections, and the need for neonatal intensive care.

The goal of this clinical trial is to learn if a common antibiotic called trimethoprim-sulfamethoxazole (TMP-SMX) can help prevent urinary tract infections (UTIs) in children and young adults who recently had a kidney transplant. Most people take TMP-SMX for about 6 months after getting a kidney transplant. In this study, researchers want to see what happens if people keep taking it for 6 more months. The main questions this study is asking are: * Does TMP-SMX lower the number of UTIs in the first year after transplant? * What side effects or problems do participants have while taking TMP-SMX? Researchers will compare TMP-SMX to a placebo (a look-alike pill that does not contain any medication) to see if TMP-SMX works to prevent UTIs. Participants will: * Take either TMP-SMX or a placebo pill by mouth every day for 6 months * Have three visits to touch base with the study team about any issues * Complete short monthly online surveys about any symptoms or side effects * Share blood and urine test results from their regular transplant clinic visits

To compare the risk of infectious complications (UTI, pyelonephritis, sepsis, hospital admission, ED visits) for patients with an indwelling urinary catheter (urethral or suprapubic) or CIC receiving 3 or 7 days of peri-operative antibiotic prophylaxis at time of Holmium Laser Enucleation of the Prostate

This study looks at how common certain antibiotic-resistant bacteria (called extended-spectrum beta-lactamase-producing Enterobacteriaceae, or E-BLSE) are in pregnant women who experience premature breaking of their water before full term. The goal is to understand how often these bacteria are found, how long they stay, and what factors increase the risk of carrying them. This information will help doctors choose the best antibiotics to protect both the mother and baby from infections during and after pregnancy. The study follows women from the time of their membrane rupture until delivery, collecting samples to track the bacteria over time.

The objective is to determine the concentration of cefazolin in the cerebrospinal fluid after a recommended antiobiotic prophylaxis by 2g of cefazolin. Our main hypothesis is that the concentration is insufficient to protect the valve from infections. The secondary objective is to compare our results to known pharmacokinetic models of cefazolin diffusion in the literature. If differences are found we would like to search clinical features that could explain it.

The goal of this observational study is to understand the risk of antibiotic resistance and changes in the human microbiome (bacteria that live inside and on us), if people use antibiotics to prevent sexually transmitted infections (STI prophylaxis, doxycycline post-exposure prophylaxis, or 'doxyPEP'). The study will assess how easy and acceptable it is to find antibiotic resistance and microbiome changes in the throats and guts of men-who-have-sex-with-men (MSM) who use STI prophylaxis. The study will recruit 108 MSM who are using and not using STI prophylaxis. Participants will visit the clinic every 6 months. At each visit, they will provide a throat swab and stool sample, and complete a questionnaire. DNA of the bacteria from the samples will be analysed to identify the bacteria and look for antibiotic resistance.

This study aims to evaluate whether probiotics can help maintain a healthy gut microbiome in patients receiving prophylactic antibiotics during elective orthopedic surgery. Antibiotics, while effective in preventing infections, can disrupt the balance of gut bacteria, leading to dysbiosis. The study hypothesizes that the use of probiotics during the perioperative period can prevent or reduce this disruption, supporting gut health and overall well-being. The research seeks to answer whether combining probiotics with routine antibiotic prophylaxis can preserve gut microbiome balance and improve patient outcomes.

The aim of this trial is to test whether postoperative antibiotics targeted towards bacteria in the urine can reduce the risk of infection after surgical removal of the bladder (cystectomy) compared to a standardised antibiotic prophylaxis. Participants undergoing cystectomy will be randomly assigned to postoperatively receive (A) a standardised orally administered antibiotic prophylaxis currently given at Rigshospitalet, Copenhagen or (B) a conventional orally administered antibiotic prophylaxis targeting bacteria found in the urine postoperatively. The investigators' hypothesis is that the targeted prophylactic antibiotic strategy will reduce the number of infection-related readmissions within 90 days of surgery compared to the standardised prophylaxis.

This study aims to investigate the impact of antibiotic prophylaxis on reducing wound infection rates following open repair of primary elective groin hernias in high-risk patients.

In this biological study, the investigators will evaluate the levels of breast milk IgA, neonatal fecal IgA, and the composition of breast milk and fecal microbiota throughout the first 12 months of life in neonates born to mothers treated or not treated with prenatal antibiotics for at least 7 days after the 32nd weeks of gestation

This study aims to show that lack of antibiotic prophylaxis to those undergoing bladder Botox injections is not significantly inferior to administering prophylaxis. By proving this, the investigators aim to decrease antibiotic use in this setting to combat the growing issue of antibiotic resistance. Participants will be randomized to antibiotic or no treatment arm. Those randomized to the treatment arm will receive oral antibiotics for 2 days pre-treatment, on the treatment day, and 2 days post-treatment. Participants will return for a follow up appointment approximately 2 weeks after treatment to assess for urinary tract infection (UTI) symptoms. They will be called again at 6 weeks for follow up.