Development of CRISPR as an Antiviral Strategy to Combat SARS-CoV-2 and Influenza.

The coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 virus, has highlighted the need for antiviral approaches that can target emerging viruses with no effective vaccines or pharmaceuticals. Here, we demonstrate a CRISPR-Cas13-based strategy, PAC-MAN (prophylactic antiviral CRISPR in human cells), for viral inhibition that can effectively degrade RNA from SARS-CoV-2 sequences and live influenza A virus (IAV) in human lung epithelial cells. We designed and screened CRISPR RNAs (crRNAs) targeting conserved viral regions and identified functional crRNAs targeting SARS-CoV-2. This approach effectively reduced H1N1 IAV load in respiratory epithelial cells. Our bioinformatic analysis showed that a group of only six crRNAs can target more than 90% of all coronaviruses. With the development of a safe and effective system for respiratory tract delivery, PAC-MAN has the potential to become an important pan-coronavirus inhibition strategy.

Temporal response of the human virome to immunosuppression and antiviral therapy.

There are few substantive methods to measure the health of the immune system, and the connection between immune strength and the viral component of the microbiome is poorly understood. Organ transplant recipients are treated with posttransplant therapies that combine immunosuppressive and antiviral drugs, offering a window into the effects of immune modulation on the virome. We used sequencing of cell-free DNA in plasma to investigate drug-virome interactions in a cohort of organ transplant recipients (656 samples, 96 patients) and find that antivirals and immunosuppressants strongly affect the structure of the virome in plasma. We observe marked virome compositional dynamics at the onset of the therapy and find that the total viral load increases with immunosuppression, whereas the bacterial component of the microbiome remains largely unaffected. The data provide insight into the relationship between the human virome, the state of the immune system, and the effects of pharmacological treatment and offer a potential application of the virome state to predict immunocompetence.

Antibiotic Prophylaxis in Infants with Grade III, IV, or V Vesicoureteral Reflux.

BACKGROUND: The efficacy of continuous antibiotic prophylaxis in preventing urinary tract infection (UTI) in infants with grade III, IV, or V vesicoureteral reflux is controversial. METHODS: In this investigator-initiated, randomized, open-label trial performed in 39 European centers, we randomly assigned infants 1 to 5 months of age with grade III, IV, or V vesicoureteral reflux and no previous UTIs to receive continuous antibiotic prophylaxis (prophylaxis group) or no treatment (untreated group) for 24 months. The primary outcome was the occurrence of the first UTI during the trial period. Secondary outcomes included new kidney scarring and the estimated glomerular filtration rate (GFR) at 24 months. RESULTS: A total of 292 participants underwent randomization (146 per group). Approximately 75% of the participants were male; the median age was 3 months, and 235 participants (80.5%) had grade IV or V vesicoureteral reflux. In the intention-to-treat analysis, a first UTI occurred in 31 participants (21.2%) in the prophylaxis group and in 52 participants (35.6%) in the untreated group (hazard ratio, 0.55; 95% confidence interval [CI], 0.35 to 0.86; P = 0.008); the number needed to treat for 2 years to prevent one UTI was 7 children (95% CI, 4 to 29). Among untreated participants, 64.4% had no UTI during the trial. The incidence of new kidney scars and the estimated GFR at 24 months did not differ substantially between the two groups. Pseudomonas species, other non-Escherichia coli organisms, and antibiotic resistance were more common in UTI isolates obtained from participants in the prophylaxis group than in isolates obtained from those in the untreated group. Serious adverse events were similar in the two groups. CONCLUSIONS: In infants with grade III, IV, or V vesicoureteral reflux and no previous UTIs, continuous antibiotic prophylaxis provided a small but significant benefit in preventing a first UTI despite an increased occurrence of non-E. coli organisms and antibiotic resistance. (Funded by the Italian Ministry of Health and others; PREDICT ClinicalTrials.gov number, NCT02021006; EudraCT number, 2013-000309-21.).

Trial of Vancomycin and Cefazolin as Surgical Prophylaxis in Arthroplasty.

BACKGROUND: The addition of vancomycin to beta-lactam prophylaxis in arthroplasty may reduce surgical-site infections; however, the efficacy and safety are unclear. METHODS: In this multicenter, double-blind, superiority, placebo-controlled trial, we randomly assigned adult patients without known methicillin-resistant Staphylococcus aureus (MRSA) colonization who were undergoing arthroplasty to receive 1.5 g of vancomycin or normal saline placebo, in addition to cefazolin prophylaxis. The primary outcome was surgical-site infection within 90 days after surgery. RESULTS: A total of 4239 patients underwent randomization. Among 4113 patients in the modified intention-to-treat population (2233 undergoing knee arthroplasty, 1850 undergoing hip arthroplasty, and 30 undergoing shoulder arthroplasty), surgical-site infections occurred in 91 of 2044 patients (4.5%) in the vancomycin group and in 72 of 2069 patients (3.5%) in the placebo group (relative risk, 1.28; 95% confidence interval [CI], 0.94 to 1.73; P = 0.11). Among patients undergoing knee arthroplasty, surgical-site infections occurred in 63 of 1109 patients (5.7%) in the vancomyin group and in 42 of 1124 patients (3.7%) in the placebo group (relative risk, 1.52; 95% CI, 1.04 to 2.23). Among patients undergoing hip arthroplasty, surgical-site infections occurred in 28 of 920 patients (3.0%) in the vancomyin group and in 29 of 930 patients (3.1%) in the placebo group (relative risk, 0.98; 95% CI, 0.59 to 1.63). Adverse events occurred in 35 of 2010 patients (1.7%) in the vancomycin group and in 35 of 2030 patients (1.7%) in the placebo group, including hypersensitivity reactions in 24 of 2010 patients (1.2%) and 11 of 2030 patients (0.5%), respectively (relative risk, 2.20; 95% CI, 1.08 to 4.49), and acute kidney injury in 42 of 2010 patients (2.1%) and 74 of 2030 patients (3.6%), respectively (relative risk, 0.57; 95% CI, 0.39 to 0.83). CONCLUSIONS: The addition of vancomycin to cefazolin prophylaxis was not superior to placebo for the prevention of surgical-site infections in arthroplasty among patients without known MRSA colonization. (Funded by the Australian National Health and Medical Research Council; Australian New Zealand Clinical Trials Registry number, ACTRN12618000642280.).

Secondary Antibiotic Prophylaxis for Latent Rheumatic Heart Disease.

BACKGROUND: Rheumatic heart disease affects more than 40.5 million people worldwide and results in 306,000 deaths annually. Echocardiographic screening detects rheumatic heart disease at an early, latent stage. Whether secondary antibiotic prophylaxis is effective in preventing progression of latent rheumatic heart disease is unknown. METHODS: We conducted a randomized, controlled trial of secondary antibiotic prophylaxis in Ugandan children and adolescents 5 to 17 years of age with latent rheumatic heart disease. Participants were randomly assigned to receive either injections of penicillin G benzathine (also known as benzathine benzylpenicillin) every 4 weeks for 2 years or no prophylaxis. All the participants underwent echocardiography at baseline and at 2 years after randomization. Changes from baseline were adjudicated by a panel whose members were unaware of the trial-group assignments. The primary outcome was echocardiographic progression of latent rheumatic heart disease at 2 years. RESULTS: Among 102,200 children and adolescents who had screening echocardiograms, 3327 were initially assessed as having latent rheumatic heart disease, and 926 of the 3327 subsequently received a definitive diagnosis on the basis of confirmatory echocardiography and were determined to be eligible for the trial. Consent or assent for participation was provided for 916 persons, and all underwent randomization; 818 participants were included in the modified intention-to-treat analysis, and 799 (97.7%) completed the trial. A total of 3 participants (0.8%) in the prophylaxis group had echocardiographic progression at 2 years, as compared with 33 (8.2%) in the control group (risk difference, -7.5 percentage points; 95% confidence interval, -10.2 to -4.7; P<0.001). Two participants in the prophylaxis group had serious adverse events that were attributable to receipt of prophylaxis, including one episode of a mild anaphylactic reaction (representing <0.1% of all administered doses of prophylaxis). CONCLUSIONS: Among children and adolescents 5 to 17 years of age with latent rheumatic heart disease, secondary antibiotic prophylaxis reduced the risk of disease progression at 2 years. Further research is needed before the implementation of population-level screening can be recommended. (Funded by the Thrasher Research Fund and others; GOAL ClinicalTrials.gov number, NCT03346525.).

Full adherence to cirrhosis quality indicators is associated with lower mortality in acute variceal bleeding: Nationwide audit.

BACKGROUND AND AIMS: Acute variceal bleeding (AVB) is a major complication in patients with cirrhosis. Using a nationwide AVB audit, we performed a nested cohort study to determine whether full adherence to the AVB quality indicator (QI) improves clinical outcomes in patients with cirrhosis and AVB. APPROACH AND RESULTS: We assessed real-world adherence to AVB QI among patients with cirrhosis admitted for AVB in all public hospitals in Singapore between January 2015 and December 2020. Full adherence was considered when all 5 QIs were fulfilled: prophylactic antibiotics, vasoactive agents, timely endoscopy, endoscopic hemostasis during index endoscopy, and nonselective beta-blockers after AVB. We compare 6-week mortality between the full adherence and suboptimal adherence groups using a propensity-matched cohort.A total of 989 patients with AVB were included. Full adherence to all AVB QI was suboptimal (56.5%). Analysis of the propensity-matched cohort with comparable baseline characteristics showed that full adherence was associated with a lower risk of early infection (20.0% vs. 26.9%), early rebleeding (5.2% vs. 10.2%), and mortality at 6 weeks (8.2% vs. 19.7%) and 1 year (21.3% vs. 35.4%) ( p <0.05 for all). While full adherence was associated with a lower 6-week mortality regardless of the MELD score, nonadherence was associated with a higher 6-week mortality despite a lower predicted risk of 6-week mortality. Despite high adherence to the recommended process measures, patients with CTP-C remain at a higher risk of rebleeding, 6-week and 1-year mortality. CONCLUSIONS: Full adherence to the AVB QI should be the target for quality improvement in patients with cirrhosis.

Nondental Invasive Procedures and Risk of Infective Endocarditis: Time for a Revisit: A Science Advisory From the American Heart Association.

There have been no published prospective randomized clinical trials that have: (1) established an association between invasive dental and nondental invasive procedures and risk of infective endocarditis; or (2) defined the efficacy and safety of antibiotic prophylaxis administered in the setting of invasive procedures in the prevention of infective endocarditis in high-risk patients. Moreover, previous observational studies that examined the association of nondental invasive procedures with the risk of infective endocarditis have been limited by inadequate sample size. They have typically focused on a few potential at-risk surgical and nonsurgical invasive procedures. However, recent investigations from Sweden and England that used nationwide databases and demonstrated an association between nondental invasive procedures, and the subsequent development of infective endocarditis (in particular, in high-risk patients with infective endocarditis) prompted the development of the current science advisory.

US Guidelines Fall Short on Short-Course Tuberculosis-Preventive Therapy.

The provision of tuberculosis-preventive therapy (TPT) to vulnerable populations is critical for global control. Shorter-course TPT regimens are highly effective and improve completion rates. Despite incorporation of 1 month of rifapentine and isoniazid into global guidelines, current US TPT guidelines do not include this as a recommended regimen, but should.

Nosocomial Infections in Adults Receiving Extracorporeal Membrane Oxygenation: A Review for Infectious Diseases Clinicians.

Over the past 10 years, there has been a rapid expansion in the use of extracorporeal membrane oxygenation (ECMO) in the care of patients with refractory cardiac or respiratory failure. Infectious diseases clinicians must reconcile conflicting evidence from limited studies as they develop practices at their own institutions, which has resulted in considerably different practices globally. This review describes infection control and prevention as well as antimicrobial prophylaxis strategies in this population. Data on diagnostics and treatment for patients receiving ECMO with a focus on diagnostic and antimicrobial stewardship is then examined. This review summarizes gaps in the current ECMO literature and proposes future needs, including developing clear definitions for infections and encouraging transparent reporting of practices at individual facilities in future clinical trials.

Comparative Effectiveness of Perioperative Antibiotic Regimens to Prevent Surgical Site Infections in Pediatric Liver Transplant Recipients.

BACKGROUND: Surgical site infections (SSIs) are a common complication in liver transplant (LT) recipients. Lack of pediatric prophylaxis guidelines results in variation in preventative antibiotic regimens. METHODS: We performed a retrospective observational study of LT recipients <18 years old using a merged data set that included data from the Pediatric Health Information System and the United Network for Organ Sharing between 2006 and 2017. The exposure was defined as the antibiotic(s) received within 24 hours of LT, with 6 categories, ranging from narrow (category 1: cefazolin), to broad). The primary outcome was presence or absence of SSI in the index admission. Mixed-effects logistic regression compared the effectiveness of each category in preventing SSI, relative to category 1. RESULTS: Of the 2586 LT, 284 (11%) met SSI criteria. The SSI rate was higher in the younger subcohort (16.2%) than in the older (8.6%), necessitating a stratified analysis. Antibiotics from category 5 were most commonly used. In the younger subcohort, the adjusted risk was increased in all categories compared with the reference, most notably in category 3 (odds ratio [OR], 2.58 [95% confidence interval: .69-9.59]) and category 6 (2.76 [.66-11.56]). In the older subcohort, estimated ORs were also increased for each category, most notably in category 4 (2.49 [95% confidence interval: .99-6.27]). None of the ORs suggested benefit from broader-spectrum prophylaxis. Our E-value assessment suggests that it's unlikely there is unmeasured confounding by indication to the degree necessary to revert ORs to protective. CONCLUSIONS: There was wide variation in antibiotic prophylaxis. Adjusted analyses did not reveal a protective benefit of broader-spectrum prophylaxis in either subcohort, suggesting that narrower regimens may be adequate.

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.

Infection risk and antimicrobial prophylaxis in bendamustine-treated patients with indolent non-Hodgkin lymphoma: An Australasian Lymphoma Alliance study.

Infection and lymphopenia are established bendamustine-related complications. The relationship between lymphopenia severity and infection risk, and the role of antimicrobial prophylaxis, is not well described. This multicentre retrospective study analysed infection characteristics and antimicrobial prophylaxis in 302 bendamustine-treated indolent non-Hodgkin lymphoma patients. Lymphopenia (<1 × 109/L) was near universal and time to lymphocyte recovery correlated with cumulative bendamustine dose. No association between lymphopenia severity and duration with infection was observed. Infections occurred in 44% of patients (50% bacterial) with 27% hospitalised; 32% of infections occurred ≥3 months post bendamustine completion. Infection was associated with obinutuzumab and/or maintenance anti-CD20 therapy, prior therapy and advanced stage. Twenty-four opportunistic infections occurred in 21 patients: ten varicella zoster virus (VZV), seven herpes simplex virus (HSV), one cytomegalovirus, one progressive multifocal leucoencephalopathy, one nocardiosis, one Pneumocystis jiroveci pneumonia (PJP) and three other fungal infections. VZV/HSV and PJP prophylaxis were prescribed to 42% and 54% respectively. Fewer VZV/HSV infections occurred in patients receiving prophylaxis (HR 0.14, p = 0.061) while PJP prophylaxis was associated with reduced risk of bacterial infection (HR 0.48, p = 0.004). Our study demonstrates a significant infection risk regardless of lymphopenia severity and supports prophylaxis to mitigate the risk of early and delayed infections.

Prophylactic Antibiotic Duration and Infectious Complications in Pancreatoduodenectomy Patients With Biliary Stents: Opportunity for De-escalation.

OBJECTIVE: The aim of this study was to compare infectious complications in pancreatoduodenectomy (PD) patients with biliary stents treated with short, medium, or long durations of prophylactic antibiotics. BACKGROUND: Pre-existing biliary stents have historically been associated with higher infection risk after PD. Patients are administered prophylactic antibiotics, but the optimal duration remains unknown. METHODS: This single-institution retrospective cohort study included consecutive PD patients from October 2016 to April 2022. Antibiotics were continued past the operative dose per surgeon discretion. Infection rates were compared by short (≤24 h), medium (>24 but ≤96 h), and long (>96 h) duration antibiotics. Multivariable regression analysis was performed to evaluate associations with a primary composite outcome of wound infection, organ-space infection, sepsis, or cholangitis. RESULTS: Among 542 PD patients, 310 patients (57%) had biliary stents. The composite outcome occurred in 28% (34/122) short, 25% (27/108) medium, and 29% (23/80) long-duration ( P =0.824) antibiotic patients. There were no differences in other infection rates or mortality. On multivariable analysis, antibiotic duration was not associated with infection rate. Only postoperative pancreatic fistula (odds ratio 33.1, P <0.001) and male sex (odds ratio 1.9, P =0.028) were associated with the composite outcome. CONCLUSIONS: Among 310 PD patients with biliary stents, long-duration prophylactic antibiotics were associated with similar composite infection rates to short and medium durations but were used almost twice as often in high-risk patients. These findings may represent an opportunity to de-escalate antibiotic coverage and promote risk-stratified antibiotic stewardship in stented patients by aligning antibiotic duration with risk-stratified pancreatectomy clinical pathways.

Randomized Trial of Prophylactic Antibiotics for Endoscopic Retrograde Cholangiopancreatography in Patients With Biliary Obstruction.

INTRODUCTION: The incidence of postendoscopic retrograde cholangiopancreatography (ERCP) infections is reported to be up to 18% in patients with biliary obstruction. Antibiotic prophylaxis may reduce the risk of infectious complications after ERCP; however, the clinical value of prophylactic antibiotics in ERCP remains controversial. METHODS: We conducted a double-blind, placebo-controlled, randomized trial to investigate whether the use of prophylactic antibiotics would reduce infectious complications after ERCP in patients with biliary obstruction. We randomly assigned patients in a 1:1 ratio to receive either a single dose of 1 g intravenous cefoxitin or normal saline as a placebo 30 minutes before undergoing ERCP. The primary outcome was the incidence of infectious complications after ERCP. RESULTS: We enrolled 378 patients, and 189 patients were assigned to each group. The risk of infectious complications after ERCP was 2.8% (5 of 176 patients) in the antibiotic prophylaxis group and 9.8% (17 of 173 patients) in the placebo group (risk ratio, 0.29; 95% confidence interval [CI], 0.11-0.74, P = 0.0073). The incidence rates of bacteremia were 2.3% (4 of 176 patients) and 6.4% (11 of 173 patients), respectively (risk ratio, 0.36; 95% CI, 0.12-1.04; P = 0.0599). The incidence rate of cholangitis was 1.7% (3 of 176 patients) in the antibiotic prophylaxis group and 6.4% (11 of 173 patients) in the placebo group (risk ratio, 0.27; 95% CI, 0.08-0.87; P = 0.0267). DISCUSSION: Antibiotic prophylaxis before ERCP in patients with biliary obstruction resulted in a significantly lower risk of infectious complications, especially cholangitis, than placebo ( ClinicalTrials.gov trial number NCT02958059).

Intramuscular versus enteral penicillin prophylaxis to prevent progression of rheumatic heart disease: Study protocol for a noninferiority randomized trial (the GOALIE trial).

BACKGROUND: Rheumatic Heart Disease (RHD) persists as a major cardiovascular driver of mortality and morbidity among young people in low-and middle-income countries. Secondary antibiotic prophylaxis (SAP) with penicillin remains the cornerstone of RHD control, however, suboptimal treatment adherence undermines most secondary prevention programs. Many of the barriers to optimal SAP adherence are specific to the intramuscular form of penicillin and may potentially be overcome by use of oral penicillin. This noninferiority trial is comparing the efficacy of intramuscular to oral penicillin SAP to prevent progression of mild RHD at 2 years. METHODS/DESIGN: The Intramuscular vs Enteral Penicillin Prophylaxis to Prevent Progression of Rheumatic Heart Disease (GOALIE) trial is randomizing Ugandan children aged 5 to 17 years identified by echocardiographic screening with mild RHD (Stage A or B as defined by 2023 World Heart Federation criteria) to Benzathine Benzyl Penicillin G (BPG arm, every-28-day intramuscular penicillin) or Phenoxymethyl Penicillin (Pen V arm, twice daily oral penicillin) for a period of 2 years. A blinded echocardiography adjudication panel of 3 RHD experts and 2 cardiologists is determining the echocardiographic stage of RHD at enrollment and will do the same at study completion by consensus review. Treatment adherence and study retention are supported through peer support groups and case management strategies. The primary outcome is the proportion of children in the Pen V arm who progress to more advanced RHD compared to those in the BPG arm. Secondary outcomes are patient-reported outcomes (treatment acceptance, satisfaction, and health related quality of life), costs, and cost-effectiveness of oral compared to intramuscular penicillin prophylaxis for RHD. A total sample size of 1,004 participants will provide 90% power to demonstrate noninferiority using a margin of 4% with allowance for 7% loss to follow-up. Participant enrollment commenced in October 2023 and final participant follow-up is expected in December 2026. The graphical abstract (Fig. 1) summarizes the flow of echocardiographic screening, participant enrollment and follow-up. DISCUSSION: The GOALIE trial is critical in global efforts to refine a pragmatic approach to secondary prevention for RHD control. GOALIE insists that the inferiority of oral penicillin be proven contemporarily and against the most important near-term clinical outcome of progression of RHD severity. This work also considers other factors that could influence the adoption of oral prophylaxis and change the calculus for acceptable efficacy including patient-reported outcomes and costs. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05693545.

An overview of risk factors, management and prevention of cochlear implant infections.

PURPOSE OF REVIEW: With cochlear implantation becoming increasingly performed worldwide, an understanding of the risk factors, preventive measures, and management of cochlear implant (CI) infection remains important given the significant morbidity and cost it conveys. RECENT FINDINGS: At the turn of the 21st century there was a decrease in rates of CI infection, particularly meningitis, following the discontinuation of positioner use for CI. However, in more recent years rates of CI infection have remained largely static. Recently, studies evaluating preventive measures such as pneumococcal vaccination, S. aureus decolonization and surgical antibiotic prophylaxis have emerged in the literature. SUMMARY: Prompt recognition of CI infection and appropriate investigation and management are key, however at present treatment is largely informed by cohort and case-control studies and expert opinion. Preventive measures including pneumococcal vaccination, S. aureus decolonization and preoperative antibiotic prophylaxis play a role in reducing rates of CI infection. However, there remains a need for well designed clinical trials to provide higher level evidence to better guide preventive measures for, and management decisions of, CI infections in the future.

Prophylactic Antibiotics Delivered Via the Respiratory Tract to Reduce Ventilator-Associated Pneumonia: A Systematic Review, Network Meta-Analysis, and Trial Sequential Analysis of Randomized Controlled Trials.

OBJECTIVES: To assess the effects of antibiotics delivered via the respiratory tract in preventing ventilator-associated pneumonia (VAP). DATA SOURCES: We searched PubMed, Scopus, the Cochrane Library, and ClinicalTrials.gov for studies published in English up to October 25, 2023. STUDY SELECTION: Adult patients with mechanical ventilation of over 48 h and receiving inhaled or instilled antibiotics (with control group) to prevent VAP were included. DATA EXTRACTION: Two independent groups screened studies, extracted the data, and assessed the risk of bias. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess the certainty/quality of the evidence. Results of a random-effects model were reported for overall and predefined subgroup meta-analyses. The analysis was primarily conducted on randomized controlled trials, and observational studies were used for sensitivity analyses. DATA SYNTHESIS: Seven RCTs with 1445 patients were included, of which six involving 1283 patients used nebulizers to deliver antibiotics. No obvious risk of bias was found among the included RCTs for the primary outcome. Compared with control group, prophylactic antibiotics delivery via the respiratory tract significantly reduced the risk of VAP (risk ratio [RR], 0.69 [95% CI, 0.53-0.89]), particularly in subgroups where aminoglycosides (RR, 0.67 [0.47-0.97]) or nebulization (RR, 0.64 [0.49-0.83]) were used as opposed to other antibiotics (ceftazidime and colistin) or intratracheal instillation. No significant differences were observed in mortality, mechanical ventilation duration, ICU and hospital length of stay, duration of systemic antibiotics, need for tracheostomy, and adverse events between the two groups. Results were confirmed in sensitivity analyses. CONCLUSIONS: In adult patients with mechanical ventilation for over 48 h, prophylactic antibiotics delivered via the respiratory tract reduced the risk of VAP, particularly for those treated with nebulized aminoglycosides.

Primary prophylaxis for spontaneous bacterial peritonitis is linked to antibiotic resistance in the Veterans Health Administration.

Spontaneous bacterial peritonitis (SBP) is a major cause of mortality. Although SBP primary prophylaxis (SBPPr) with fluoroquinolones and trimethoprim-sulfamethoxazole (TMP-SMX) is often used, resistance could reduce its benefit. AIM: Analyze peritoneal fluid resistance patterns in patients with a first SBP episode with/without SBPPr using the Veterans Health Administration corporate data warehouse and to evaluate national antibiograms. Corporate data warehouse data were extracted using validated International Classification of Disease-9/10 codes, culture, resistance data, and outcomes of 7553 patients who developed their first inpatient SBP between 2009 and 2019 and compared between those with/without SBPPr. Escherichia coli ( E. coli ) and Klebsiella pneumoniae ( K. pneumoniae ) sensitivity to ciprofloxacin and TMP-SMX was calculated using 2021 Veterans Health Administration antibiogram data from all states. The most common isolates were E. coli , K. pneumoniae , and Staphylococcus species. Veterans taking ciprofloxacin SBBPr had higher fluoroquinolone resistance (34% vs 14% no SBPPr, p <0.0001); those taking TMP-SMX had higher TMP-SMX resistance (40% vs 14%, p <0.0001). SBPPr patients showed higher culture positivity, greater length of stay, higher second SBP, and higher probability of liver transplant rates versus no SBPPr. Multivariable models showed SBBPr to be the only variable associated with gram-negative resistance, and SBPPr was associated with a trend toward longer length of stay. E. coli ciprofloxacin sensitivity rates were 50%-87% and 43%-92% for TMP-SMX. K. pneumoniae ciprofloxacin sensitivity was 76%-100% and 72%-100% for TMP-SMX. CONCLUSION: Among patients who developed their first SBP episode, there was a higher prevalence of antibiotic resistance in those on SBPPr, with a high rate of fluoroquinolone resistance across the Veterans Health Administration sites.

An observational cohort study on the effects of extended postoperative antibiotic prophylaxis on surgical-site infections in low- and middle-income countries.

BACKGROUND: Worldwide, approximately one in six inpatient antibiotic prescriptions are for surgical-infection prophylaxis, including postoperative prophylaxis. The WHO recommends against prolonged postoperative antibiotics to prevent surgical-site infection. However, in many low- and middle-income countries, postoperative antibiotic prophylaxis is common due to perceptions that it protects against surgical-site infection and data informing recommendations against antibiotic administration are largely derived from high-income countries. The aim of this study was to describe postoperative antibiotic-prescribing patterns and related surgical-site infection rates in hospitals in low- and middle-income countries. METHODS: Patients from 19 hospitals in Ethiopia, Madagascar, India, and Bolivia with wound class I and II operations were included. Data on antibiotic administration, indication, surgical-site infection, length of hospital stay, and adherence to perioperative infection-prevention standards were collected by trained personnel. The association between postoperative antibiotic prophylaxis for greater than or equal to 24 h and surgical-site infection was analysed via modified robust Poisson regression, controlling for patient and procedural factors and degree of adherence to perioperative infection-prevention practices. RESULTS: Of 8714 patients, 92.9% received antibiotics for prophylaxis after surgery and 27.7% received antibiotics for greater than or equal to 24 h. Patients receiving postoperative prophylaxis for greater than or equal to 24 h did not have lower surgical-site infection rates (Relative risk 1.09 (95% c.i. 0.89 to 1.33); P = 0.399), but the length of hospital stay was 1.4 days longer (P < 0.001). CONCLUSION: Prolonged postoperative antibiotics did not reduce surgical-site infection, but pervasive use was associated with a longer length of hospital stay, in resource-limited healthcare systems. With the growing threat of antimicrobial resistance, surgical initiatives to implement antimicrobial stewardship programmes in low- and middle-income countries are critical.

Influence of patient characteristics on microbial composition in surgical-site infections: insights from national surveillance study.

BACKGROUND: Although the impact of surgery- and patient-dependent factors on surgical-site infections (SSIs) have been studied extensively, their influence on the microbial composition of SSI remains unexplored. The aim of this study was to identify patient-dependent predictors of the microbial composition of SSIs across different types of surgery. METHODS: This retrospective cohort study included 538 893 patients from the Swiss national infection surveillance programme. Multilabel classification methods, adaptive boosting and Gaussian Naive Bayes were employed to identify predictors of the microbial composition of SSIs using 20 features, including sex, age, BMI, duration of surgery, type of surgery, and surgical antimicrobial prophylaxis. RESULTS: Overall, SSIs were recorded in 18 642 patients (3.8%) and, of these, 10 632 had microbiological wound swabs available. The most common pathogens identified in SSIs were Enterobacterales (57%), Staphylococcus spp. (31%), and Enterococcus spp. (28%). Age (mean feature importance 0.260, 95% c.i. 0.209 to 0.309), BMI (0.224, 0.177 to 0.271), and duration of surgery (0.221, 0.180 to 0.269) were strong and independent predictors of the microbial composition of SSIs. Increasing age and duration of surgical procedure as well as decreasing BMI were associated with a shift from Staphylococcus spp. to Enterobacterales and Enterococcus spp. An online application of the machine learning model is available for validation in other healthcare systems. CONCLUSION: Age, BMI, and duration of surgery were key predictors of the microbial composition of SSI, irrespective of the type of surgery, demonstrating the relevance of patient-dependent factors to the pathogenesis of SSIs.

Local infections are a frequent problem after surgery. The risk factors for surgical infections have been identified, but it is unclear which factors predict the type of microorganisms found in such infections. The aim of the present study was to assess patient factors affecting the composition of microorganisms in surgical infections. Data from 538 893 patients were analysed using standard statistics and machine learning methods. The results showed that age, BMI, and the duration of surgery were important in determining the bacteria found in the surgical-site infections. With increasing age, longer operations, and lower BMI, more bacteria stemming from the intestine were found in the surgical site, as opposed to bacteria from the skin. This knowledge may help in developing more personalized treatments for patients undergoing surgery in the future.