Positive Microbiological Cultures Research Articles

Presepsin Does Not Predict Risk of Death in Sepsis Patients Admitted to the Intensive Care Unit: A Prospective Single-Center Study.

Background: Sepsis is defined as life-threatening organ dysfunction caused by an abnormal host response to infection. The study aimed to evaluate the utility of presepsin (P-SEP) in predicting the risk of death in patients with sepsis at the time of intensive care unit (ICU) admission. Methods: Adult patients were included in the study if they met SEPSIS-3 criteria at ICU admission. Demographic and clinical data were collected. The following inflammatory parameters were determined: C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6), and presepsin (P-SEP). Material was collected for microbiological testing depending on the suspected source of infection. The primary endpoint was patient death before ICU discharge. The secondary endpoint was a positive microbiological test result. Results: Eighty-six patients were included in the study. Thirty patients (35%) died before discharge from the ICU. There was no difference in P-SEP, CRP, PCT, and IL-6 values between patients who survived and those who died (p > 0.05 for all). P-SEP, CRP, PCT, and IL-6 were determined at ICU admission and did not accurately predict the risk of death in ROC curve analysis (p > 0.05 for all). Confirmation of the location of the focus of bacterial infection by microbiological testing was obtained in 43 (49%) patients. P-SEP, PCT, CRP, and IL-6 were significantly higher in patients with positive microbiological findings. Conclusions: In patients with suspected sepsis admitted to the Intensive Care Unit, presepsin does not accurately predict the risk of in-hospital death, but it can predict a positive microbiological culture.

Bacterial profile of wound site infections and evaluation of risk factors for sepsis among road traffic accident patients from Apex Trauma Centre, Northern India.

Background. Among the most significant yet often ignored health issues worldwide are trauma and accidental injuries. India accounts for 11% of global deaths in road accidents, the highest in the world, according to the World Bank report. There are limited data about the bacterial contamination of road traffic accident (RTA) wounds and their antibiotic susceptibility patterns. Materials and Methods. This prospective study was conducted in a tertiary care centre in northern India from January 2023 to January 2024. Wound deep swabs or aspirates were collected from RTA patients with traumatic injuries at different time intervals. Gram stain and culture were performed, and positive aerobic culture was subjected to antibiotic susceptibility testing. Organism identification was done using MALDI-TOF MS and routine biochemical tests. Blood samples were also collected to rule out bloodstream infections during follow-up if the patient became febrile or showed symptoms of systemic infection. Sepsis was defined in those patients who had two or more scores in the systemic inflammatory response syndrome criteria with a positive microbiological culture. Risk factors were evaluated for sepsis on the basis of the patient's vitals, injury characteristics, procalcitonin, Glasgow Coma Scale (GCS) score, need for mechanical ventilation and complete blood count, which were obtained from the patient's admission file. Results. A total of 189 wound samples were collected, of which 99 (52.38%) samples showed the growth of microorganisms. The aerobic isolates included 69 (69.69%) Gram-negative bacilli, of which the majority were Klebsiella pneumoniae, 28 (28.28%) Gram-positive cocci, of which the majority were Staphylococcus aureus and 2 (2.02%) anaerobic isolates. Among the Gram-negative isolates, none of the isolates were resistant to colistin. All S. aureus isolates were susceptible to vancomycin, teicoplanin and levonadifloxacin. Sepsis developed in 50 (26.45 %) patients. Significant risk factors evaluated for sepsis were a raised procalcitonin level, a low GCS score, a higher injury severity score, the need for mechanical ventilation and a raised quick sequential organ failure assessment score. Conclusion. It is essential to ascertain the profile of microorganisms isolated from RTA wounds in order to reduce antibiotic resistance and deliver efficient treatment.

Chromoblastomycosis: A Single Centre Clinical Laboratory Experience of Seven Years (2016-2022) and Literature Review From Pakistan.

Chromoblastomycosis (CBM) is a chronic infection of skin and subcutaneous tissue. CBM cases have been reported in local literature from Pakistan with heterogenous demographic, diagnostic and therapeutic information. The objective of this study is to share the experience of CBM from a large tertiary care hospital laboratory in Pakistan. This was a retrospective observational study. Histopathology and microbiology data of suspected CBM between 2016 and 2022 was retrieved. Patients' demographics, site of involvement, histopathological findings and positive microbiology cultures were assessed. Literature search on Google Scholar, PubMed and PakMediNet was done between 1990 and 2023 with multiple terms. A total of 16 CBM cases were identified; 14 were histopathology positive and two were both histopathology and culture positive. The median age was 21 years, and 11 patients were male. The predominant site was lower extremities followed by the face. Severe acanthosis, hyperkeratosis and granuloma with sclerotic bodies were observed in all histopathology slides. Alternaria spp. and Phialophora spp. were isolated from two culture-positive cases. A total of nine cases of CBM were reported from Pakistan in PubMed non-indexed journal. CBM is not a commonly thought of disease when evaluating skin lesions in Pakistan. A high index of suspicion when assessing patients who may have a history of trauma, exposure to soil and suggestive lesions is reasonable. An integrated approach between clinicians, histopathologist and microbiologist is required to do early identification and therapeutic interventions.

Vitamin B12 status and the risk of developing sepsis in patients with bacterial infection: a prospective observational cohort study

BackgroundData have shown that vitamin B12 has immunomodulatory effects via different pathways, which could influence the pathophysiology of sepsis. The objective of this study was to investigate whether vitamin B12 levels, assessed by the measurement of holotranscobalamin (HTC), total vitamin B12 (B12), and methylmalonic acid (MMA, which accumulates in case of B12 deficiency), are associated with the development of sepsis in patients with onset of bacterial infection.MethodsThis was a single-center, prospective observational pilot study. Adult patients who presented to the emergency department with bacterial infection confirmed by a positive microbiological culture result were included in the study and followed up for 6 days to assess whether they developed sepsis or not. The primary objective was to compare HTC concentration in patients who developed sepsis to those who did not develop sepsis. Secondary objectives were the evaluation of B12 and MMA concentrations in those two groups. Multiple logistic regression models were used, with presence of sepsis as the outcome variable, and HTC, B12, and MMA concentrations as predictor variables, separately, and adjusted for potential confounders.ResultsFrom 2019 to 2022, 2131 patients were assessed for eligibility, of whom 100 met the inclusion criteria. One patient was excluded from the analysis due to missing data. Of the 99 patients, 29 developed sepsis. There was no evidence for an association between HTC or B12 concentration and the development of sepsis (OR 0.65, 95% CI 0.31–1.29, p = 0.232, OR 0.84, 95% CI 0.44–1.54, p = 0.584, respectively). There was an association between MMA concentration and the development of sepsis, with a positive effect, i.e. with increasing MMA, the odds for sepsis increased (OR 2.36, 95% CI 1.21–4.87, p = 0.014). This association remained significant when adjusted for confounders (OR 2.72, 95% CI 1.23–6.60, p = 0.018).ConclusionsOur study found an association between elevated MMA concentration and the development of sepsis. We did not find an association between HTC and B12 concentrations and the development of sepsis. Further, larger studies are warranted, as it could lead to interventional trials investigating whether B12 supplementation provides a clinical benefit to patients with infection or sepsis.Trial registrationThe study was registered on ClinicalTrials.gov under the identifier NCT04008446 on June 17, 2019.

Assessment of the Antimicrobial Sensitivity Pattern of Bacterial Pathogens Causing Uncomplicated Urinary Tract Infection in Female Patients at a Tertiary Level Hospital

Introduction: Urinary tract infection (UTI) is a common infectious disease which affects both, men and women. It is a significant health concern due to multidrug-resistant (MDR) organisms. Therefore, it is necessary to have a current understanding of the antibiotic susceptibility (AS) pattern of uropathogens to manage UTI effectively. Objective: This study aims to assess the antimicrobial sensitivity pattern of bacterial pathogens causing uncomplicated urinary tract infection in female patients. Methods: A prospective study was conducted at the Department of Pharmacology & Therapeutics in collaboration with the Department of Microbiology at SBMC, the Outpatient Department of Medicine, and Gynae & Obstetrics at Sher-E-Bangla Medical College, Barishal, Bangladesh, from January 2017 to December 2017. Clean catch midstream urine samples were collected and processed using standard guidelines for microbiological procedures. Positive microbiological cultures were found in 200 of the 314 patients, Data on socio-demographic, clinical, and risk factors were collected using a structured questionnaire. Results: In this study, the age of the subjects ranged from 15 to 75 years, majority of subjects (38.4%) belonged to age group of 45-60 years. The mean age was found 42.6±11.4 years. Out of 200 cases, E. coli was the most predominant gram-negative bacteria. Antibiotic susceptibility testing revealed that the pathogenic bacteria isolated from urine samples were MDR organisms. Aminoglycoside antibiotics such as Amikacin and gentamycin were the most effective drugs. Conclusion: Urinary tract infections are prevalent, affecting 64% of cases, with all isolates showing resistance to commonly used antibiotics. Therefore, it is recommended to provide health education on the transmission and causes of urinary tract infections.

Brucella spp. in Wildlife of the Lombardy Region, Northern Italy.

Surveillance data collected in the period 2017-20 for Brucella spp. in wildlife of the Lombardy Region in northern Italy were used to describe the exposure of the wildlife species to Brucella spp. in wild boar (Sus scrofa), European brown hare (Lepus europaeus), fallow deer (Dama dama), red deer (Cervus elaphus), and roe deer (Capreolus capreolus). Among the tested species, wild boar (n=6,440) showed the highest percentage of seropositive samples (5.9%). Notably, wild boars of perifluvial area of the Po River showed higher percentages of positivity than those of the pre-Alpine district. In addition, during the hunting season in 2018, 95 organs (uterus or testes, spleen, and submandibular lymph nodes) from wild boar of the perifluvial area of the Po River were collected for bacteriological examination. Brucella suis was isolated in culture from 18.9% of tested lymph nodes. These serological and microbiological results highlight the presence of B. suis in wild boar and suggest the importance of wild boar as a reservoir for B. suis. Comparison of the spatial distribution of Brucella-seropositive wild boars with the location of backyard swine farms revealed a higher chance of contact between the two populations only in the areas where the lower percentage of seropositive samples was observed. Conversely, the high percentage of seropositive samples observed in the Po River area coupled with positive microbiological cultures suggest a greater risk of infection for the humans directly or indirectly involved in wild boar hunting activity. These results may serve as a basis to establish sound wildlife management and to adopt education campaigns aimed at reducing the risk of human infection in people involved in wild boar hunting related activities.

Ceftazidime-Avibactam as a Salvage Treatment for Severely Infected Immunosuppressed Children.

Multidrug-resistant Gram-negative bacteria (MDR-GNB) are becoming increasingly common around the world, with carbapenems frequently serving as a last resort but being threatened by the growing incidence of carbapenemase-producing bacteria. Ceftazidime-avibactam (CAZ/AVI) is a potential agent against MDR-GNB but with limited clinical experience, particularly in critically ill immunosuppressed children. This study analyzed the use of CAZ/AVI as salvage treatment in severely infected immunosuppressed children from September 2019 to July 2022. Patients with confirmed GNB infection who received CAZ/AVI were matched with patients who received other antibiotics. Twenty-five critically ill immunosuppressed children treated with CAZ/AVI were included. The majority had hematologic diseases. All patients presented with sepsis in all 30 courses. Septic shock presented in 36.7% of these courses. The primary sites of infection included bloodstream infection (20.0%), skin and skin structure infection (20.0%), intra-abdominal infection (13.3%) and hospital-acquired pneumonia (10.0%). Twelve of the 25 (48.0%) patients had positive microbiological cultures, mainly Pseudomonas aeruginosa and Klebsiella pneumoniae, including 5 carbapenem-resistant GNB-infected cases. Fifteen (50.0%) courses presented clinical improvement. For the initial course of each patient, the clinical response rate of the GNB recovered group was significantly higher than that of the group without GNB recovery (66.7% vs 23.1%, P = 0.047). The 14-day and 30-day mortality rates were 24.0% and 28.0%, respectively, which were significantly correlated with the absence of GNB recovery (P = 0.004 and 0.024, respectively) and hospital-acquired pneumonia as the primary site of infection (P = 0.001 and 0.006, respectively). There was no significant difference in major outcomes between patients who received CAZ/AVI and matched patients who received other antibiotics. CAZ/AVI could be considered a salvage strategy for immunosuppressed children with confirmed GNB infection. Caution should be taken when CAZ/AVI is applied to these patients in the absence of GNB recovery.

An Improved Algorithm for the Detection of Ventilator Associated Pneumonia

Background: Ventilator associated pneumonia (VAP) is associated with significant rates of morbidity and all-cause mortality. Active VAP surveillance can identify risk factors for which targeted preventive measures can be implemented. However, surveillance efforts are complicated by challenges associated with accurate VAP diagnosis. We aimed to improve the accuracy and automation of existing VAP diagnostic algorithms to better identify patients at risk. Methods: The study was conducted at NYU Langone Health from June 2022 through December 2023. We created a semi-automated VAP surveillance system using the Centers for Disease Control & Prevention (CDC) ventilator associated event (VAE) definition as a base framework (Figure 1). We modified this definition to include additional elements, such as having a sputum culture ordered within 48 hours of worsening oxygen status, regardless of culture result. Using this algorithm—followed by manual clinician reviews—we retrospectively assessed possible VAP cases to determine the ability of our surveillance system to correctly identify VAP. Results: Of the 123 possible VAP cases identified through our automated system, 75 (61%) were correctly diagnosed as VAP after clinical review. This reflects a rate of 1.5 infections per 1000 ventilation days across the system and 1.85 infections per 100 patients ventilated for greater than 2 days. Of the 48 remaining patients without VAP after clinical review, 25% (n=12) were characterized as having hospital-acquired pneumonia, 21% (n=10) as acute respiratory distress syndrome or infection at another site and 10% (n=5) as pulmonary embolism/infarction. Among all patients identified through this automated system (VAP and non-VAP), 53% experienced in-hospital death. Discussion: Our automated VAP surveillance algorithm identified 123 cases of potential VAP, 61% of which were consistent with a clinical diagnosis of VAP upon manual chart review. Our VAP rate of 1.5 infections per 1000 ventilation days was similar to published rates at other North American hospital systems. The high in-hospital mortality rate among these patients highlights the need for improved surveillance systems and earlier interventions to reduce the risk of VAP. There are several limitations to the CDC’s VAE definition, including its requirement of a positive microbiologic culture and focus on sputum quality. This potentially misses cases of culture-negative VAP in patients receiving antibiotics prior to sputum collection. Our goal is to continue to validate and improve our algorithm’s ability to correctly identify patients with clinical VAP, so that targeted prevention efforts can be focused upon the patients with the highest risk for poor outcomes.Disclosure: Madeline DiLorenzo: Stocks - Abbvie, Amgen Inc., Becton Dickinson, Biogen Inc., Bristol Myers and Squibb, CVS Health, Davita Inc., Elevance Health, Gilead, Henry Schein, Hologic Inc., Humana Inc., Jazz Pharmaceuticals, Laboratory Corp, Merck and Co., Quest Diagnostics, ResMed Inc., Teladoc Health, Vertex Pharmaceuticals, West Pharmaceuticals

Infections as a “cause of death” in patients with cancer: Need improved focus to improve outcomes?

e23281 Background: Infectious diseases are a significant contributor to both morbidity and mortality in cancer patients. Cancer's impact on the immune system and the immunosuppressive effect of its treatment make patients more susceptible to infection. Furthermore, cancer's involvement of multiple organs increases the risk of infection. It is crucial to consider causes of death beyond cancer when evaluating overall survival, as effective treatment alone is not sufficient. We conducted a study to investigate infection as a cause of in-hospital death among cancer patients in a tertiary hospital. Methods: We collected data on the causes of death for all patients with cancer who passed away in our hospital in 2022 and 2023. This included detailed medical histories, investigation charts, and test results related to infections. Infections were defined as those listed as the cause of death in the hospital records. We had access to data on age, sex, primary tumor site, and laboratory test results related to infections. Infections were identified through microbiological cultures and PCR panels for bacteria, fungi, and viruses. Percentages were used to analyze standard statistical variables. Results: The death toll for the year period amounted to 113 individuals, which included 77 males and 36 females, with ages ranging from 16 to 88 and a mean of 63.2 years, with a median of 64 years. Among the 91 patients with classifiable stages, 86% had metastatic disease. Many of the patients, amounting to 75%, were suspected or confirmed to have contracted an infection at the time of death. In 69/113 (61%) cases, the infections were confirmed through laboratory and radiological tests. Out of 90 patients in whom cultures and infection PCR tests were sent, 53/90 (59%) showed positive microbiology reports, and 37/90 (41%) had negative microbiological culture reports. Among the 41 patients with positive microbiology culture reports, 41% had blood culture positivity but no localizing signs, 34% had lung infections, 15% had both lung and blood culture positivity, and around 8% had urological origins of infection. Around 60% of the patients had bacterial infections, while approximately 4% had documented fungal infections. No cases of viral infections were recorded. Half of the patients, or 50%, were directly admitted to the Intensive Care Unit (ICU) during their last admission, while the remaining 50% were transferred from the ward to the ICU. Infection as a cause of death was attributed to 81/113 (71.6%) of the patients. Conclusions: Infectious diseases appear to be a major cause of death. Its control may play a significant role in reducing the overall survival and improving quality of life. Increased focus on detection and intervention to manage infections could substantially add to desirable endpoints in oncology. Therefore, there is an urgent need to focus on the management of infections.

Crucial Insights: Post-Op Spinal Infections in Lumbar Fusion

Postoperative spinal infections following lumbar fusion with posterior lumbar interbody fusion (PLIF) are a concerning complication, particularly in cases of degenerative spinal disease. However, factors contributing to infection risk remain unclear. This retrospective study analyzed data from 124 adults who underwent instrumented fusion for degenerative spinal conditions between 2015 and 2020. Multivariate proportional hazards regression identified risk factors associated with surgical site infections (SSI). Results revealed a 16.9% incidence of SSI, with 92.4% of cases showing positive microbiological cultures. Prolonged hospital stay, prior surgeries, advanced age, diabetes, and obesity were correlated with infection risk. Notably, 95% of infected patients were successfully treated with surgical intervention or antibiotics without hardware removal. This underscores the importance of early identification and intervention in managing postoperative spinal infections, mitigating the need for hardware removal and improving patient outcomes.

Risk factors and clinical characteristics of surgical site infections in athletes undergoing Achilles tendon repair surgery.

Achilles tendon ruptures are common in athletes, requiring surgical intervention. However, the risk of surgical site infections (SSIs) post-surgery poses significant challenges. This study aims to analyse the risk factors and microbial aetiology associated with SSIs in athletes undergoing Achilles tendon repair. A comprehensive retrospective analysis was conducted from May 2021 to July 2023. The study included 25 patients with SSIs (case group) and 50 patients without SSIs (control group) post Achilles tendon repair surgery. Inclusion criteria encompassed patients with medically confirmed Achilles tendon ruptures who underwent surgical repair. Exclusion criteria included prior tendon pathologies and significant chronic illnesses. Diagnostic criteria for SSIs involved symptoms like elevated body temperature and localized tenderness, along with laboratory confirmations such as positive microbiological cultures. The study utilized VITEK® 2 for bacterial identification and involved statistical analyses like univariate and multivariate logistic regression. The study identified Staphylococcus aureus as the primary pathogen in SSIs. Significant risk factors included lack of prophylactic antibiotic use, presence of diabetes, open wounds and prolonged surgery duration. Univariate analysis revealed stark contrasts in these factors between infected and non-infected groups, while multivariate analysis underscored their importance in SSI development. S. aureus emerged as the predominant pathogen in SSIs post Achilles tendon repair. Critical risk factors such as absence of prophylactic antibiotics, diabetes, open wounds and extended surgery duration play a vital role in SSIs. Addressing these factors is essential for better postoperative outcomes in Achilles tendon repair surgeries.

The prevalence and clinical context of antimicrobial resistance amongst medical inpatients at a referral hospital in Rwanda: a cohort study

BackgroundAntimicrobial resistance (AMR) is a growing global concern. AMR surveillance is a crucial component of the international response; however, passive surveillance of laboratory data is limited without corresponding patient-level clinical data. This study sought to examine the burden of AMR amongst medical inpatients in Rwanda, in the context of their clinical presentations and prior antibiotic exposures.MethodsThis cohort study was conducted over a 9-month period at a tertiary referral hospital in Kigali, Rwanda. We enrolled 122 adult medical inpatients with a history of fever and a positive microbiological culture result. Data were collected regarding the clinical and microbiological aspects of their admission.ResultsThe most common diagnoses were urinary tract infection (n = 36, 30%), followed by pneumonia (n = 30, 25%) and bacteraemia (11 primary [9%] and 10 catheter-related [8%]). The most common pathogens were E. coli (n = 40, 33%) and Klebsiella pneumoniae (n = 36, 30%). The cohort were heavily antibiotic-exposed at the time of culture with 98% of patients (n = 119) having received an antibiotic prior to culture, with a median exposure of 3 days (IQR 2–4 days). Eighty patients (66%) were specifically prescribed ceftriaxone at the time of culture. Gram-negative organisms predominated (82% [100/122]) and exhibited high rates of resistance, with only 27% (21/77) being susceptible to ceftriaxone, 2.4% (2/82) susceptible to co-amoxiclav and 44% (8/18) susceptible to ciprofloxacin. Susceptibility amongst Gram-negatives was relatively preserved to amikacin (91%, 79/87) and imipenem (85%, 70/82). There were no cases of methicillin-resistant Staphylococcus aureus (0/12) or vancomycin-resistant enterococci (0/2). Discordant antibiotic therapy was significantly associated with in-hospital mortality (OR 6.87, 95%CI 1.80–45.1, p = 0.014).ConclusionsThis cohort highlights high rates of resistance amongst Gram-negative organisms in Rwanda, including the presence of carbapenem resistance. Nonetheless, the detailed prescribing data also highlight the challenges of using routine laboratory data to infer broader AMR prevalence. The significant exposure to empiric broad-spectrum antibiotic therapy prior to culturing introduces a selection bias and risks over-estimating the burden of resistant organisms. Broadening access to microbiological services and active surveillance outside of teaching hospitals are essential to support national and international efforts to curb the growth of AMR in low-resource settings.

Application of the New Irrigation Protocol to Reduce Recurrence Rate in the Management Of Periprosthetic Joint Infection.

Irrigation is a conventional treatment for acute and chronic periprosthetic joint infections (PJI). However, there has been no unified standard for irrigation during surgery for PJI in the past, and the efficacy is uncertain. The purpose of this study is to create a new irrigation protocol to enhance the infection control rate and reduce the postoperative recurrence rate of PJI patients. We conducted a single-institution retrospective review with a total of 56 patients who underwent revision total hip or knee arthroplasties due to PJI from January 2011 to January 2022. Conventional irrigation (CI) was used in 32 cases, and standard operating procedure of irrigation (SOPI) was used in 24. The CI protocol carries out an empirical irrigation after debridement, which is quite random. Our SOPI protocol clearly stipulates the soaking concentration and time of hydrogen peroxide and povidone-iodine. The irrigation is carried out three times, and tissue samples are taken from multiple parts before and after irrigation, which are sent for microbial culture. The important statistical indicators were the rate of positive microbiological culture and postoperative recurrence rate with an average follow-up of 24 average months. The drainage volume was lower in the SOPI group than in the CI group on postoperative day 3 (p < 0.01) and 7 (p = 0.016). In addition, the percentage of positive microbiological cultures after the third irrigation was less than that before (p < 0.01) and after (p < 0.01) the first irrigation. The most common causative organism was Staphylococcus aureus, which was detected in 25.0% and 12.5% of the SOPI and CI groups, respectively. The failure rate at the final follow-up was 8.3% and 31.3% (p = 0.039) for the SOPI and CI groups, respectively. Compared with the traditional CI method, SOPI standardized the soaking time of hydrogen peroxide and povidone-iodine, increased the frequency of and irrigation, and proved that microorganisms were almost completely removed through the microbial culture of multiple tissues. SOPI has the potential to become a standardized irrigation process worthy of promotion, effectively reducing the postoperative recurrence rate of PJI patients.

Relationship of imipenem therapeutic drug monitoring to clinical outcomes in critically ill patients: a retrospective cohort study.

The primary objective of this study was to evaluate the predictors associated with target concentration (non-)attainment of imipenem in critically ill patients. The secondary objective was to explore the correlation between achieving imipenem target concentrations and clinical outcomes of therapy. A retrospective cohort study was conducted in critically ill patients treated with imipenem. Clinical data were extracted from the patients' electronic medical records. The pharmacokinetic/pharmacodynamic target was defined as free imipenem concentrations above the minimum inhibitory concentration (MIC) of the pathogen at 100% (100%fT>MIC) of the dosing interval. Factors associated with the non-attainment of target concentrations were evaluated using binomial logistic regression. Kaplan-Meier analysis was used to investigate the correlation between (non-)attainment targets and 30-day mortality. A total of 406 patients were included, and 55.4% achieved the target of 100%fT>MIC. Regression analysis identified an initial daily dose of imipenem ≤ 2 g/day, augmented renal clearance, age ≤ 60 years, recent surgery, and absence of positive microbiology culture as risk factors for target non-attainment. Achieving the 100%fT>MIC target was significantly associated with clinical efficacy but not with 30-day mortality. Selective application of therapeutic drug monitoring in the early stages of imipenem treatment for critically ill patients can improve clinical outcomes. Further research should explore the potential benefits of TDM-guided dosing strategies for imipenem in critical care settings.

Increase in antibiotic resistance in diabetic foot infections among peruvian patients: a single-center cross-sectional study.

Diabetic foot is one of the most significant complications in individuals with diabetes and is closely associated with lower limb amputation. The antibiotic susceptibility patterns of these bacterial isolates play a critical role in guiding effective treatment strategies We aimed to determine the most common bacterial agents causing diabetic foot infections in a tertiary-care hospital in Peru. Clinical and microbiological data were collected from 181 patients diagnosed with diabetic foot infections and positive microbiological culture results. All the samples were analyzed with the Vitek 2 compact system and the cut-off points were defined with the CLSI M100 guide. The data were segregated based on mono-microbial or poly-microbial cultures, bacterial types, and antibiotic susceptibility profiles. A total of 32 bacterial species were identified, predominantly Gram-negative (63%). The most frequent bacterial agents isolated were Staphylococcus aureus (19.9%), Escherichia coli (12.2%), Pseudomonas aeruginosa (8.3%), and Proteus vulgaris (6.6%). These bacteria commonly exhibited resistance to Ampicillin, Ciprofloxacin, Levofloxacin, Trimethoprim-sulfamethoxazole, and Cefuroxime. E. coli showed the highest antibiotic resistance (19 antibiotics), while Gentamicin, Tobramycin, and Levofloxacin demonstrated the highest sensitivity against the most prevalent bacteria. Gram-negative bacteria also exhibited notable antibiotic-susceptibility to Meropenem, Piperacillin/tazobactam, and Amikacin. Regarding the presence of Extended-Spectrum Beta-Lactamase, 54 isolates tested positive, with 35 (64.8%) and 14 (42.4%) of these being S. aureus and E. coli. Bacterial agents causing diabetic foot infections pose a constant concern, particularly due to the increasing antibiotic resistance observed. This difficulty in treating the condition contributes to a higher risk of amputation and mortality. Further research on bacterial susceptibility is necessary to determine appropriate dosages for pharmacological treatment and to prevent the overuse of antibiotics.

1429. Temperature and Humidity Variations in the Operating Room: A Risk Assessment

Abstract Background The American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) recommends that hospital operating rooms (OR) are controlled for temperature and humidity with established ranges but does allow for exceedances for surgeons and surgical procedures. There is currently no clear consensus or established thresholds for out-of-range temperature and humidity ranges in relation to risk for surgical site infections (SSI). A study was performed at Memorial Sloan Kettering Cancer Center (MSKCC) to further examine if temperature and humidity deviations pose a patient safety risk. Methods The study included 5600 surgical procedures that were performed at MSKCC between September 2021 and January 2022 where temperature and humidity logs were available. Procedures were broken into groups based on in- (n=4419) and out-of-range (n=1187) temperatures and in- (n=5225) and out-of-range (n=381) humidity. SSIs following the procedure were identified using targeted positive microbiology cultures and within NHSN (National Healthcare Safety Network) surveillance periods. Chi-square and Fisher’s exact statistical tests were used to determine if there was a significant difference between groups where p &amp;lt; 0.05. Breakdown of eligible procedures and follow up Table represents the total number of eligible procedures with environmental parameters and SSI follow up period. Results There was no significant impact on SSI for out-of-range humidity (p=0.15). There was a significantly higher SSI rate observed for out-of-range temperatures (p=0.04) more specifically low out- of-range temperatures (p=0.02). A sub-analysis was performed for low temperatures based on procedures by duration. Significance of the finding was lost when surgery duration was 4 hours or greater. Conclusion If there was a true correlation between SSI and low ambient temperature, we would have expected to see a strengthening of SSI risk with longer procedures. This study suggests that temperature and humidity deviations out of the recommended guidelines in the operating room do not pose additional risks for surgical site infections and limited exceedances can be permitted without risking patient safety. Disclosures All Authors: No reported disclosures

The impact of immunosuppressive therapy on secondary infections and antimicrobial use in COVID-19 inpatients: a retrospective cohort study

BackgroundImmunosuppressive therapies have become a cornerstone of the management of severe COVID-19. The impact of these therapies on secondary infections and antimicrobial prescribing remains unclear. We sought to assess antimicrobial use and the incidence of bacterial and fungal infections in patients with severe COVID-19, and to explore their associations with receipt of immunosuppressive therapies.MethodsOur retrospective cohort study included 715 hospitalised, adult patients with severe COVID-19 admitted to St George’s Hospital, London, UK, during the first UK pandemic wave (1st March–10th June 2020). Co-infections (occurring within 48 h of admission) and secondary infections (≥ 48 h) were defined as a positive microbiological culture with supporting clinical, radiological or laboratory data to suggest true infection. Cox regression models with time-dependent covariates were used to explore the association between immunosuppressant use and secondary infection.ResultsMicrobiologically confirmed co-infection occurred in 4.2% (n = 30) and secondary infection in 9.3% (n = 66) of the cohort (n = 715) and were associated with in-hospital mortality (48% vs 35%, OR 1.8, 95%CI 1.1–2.7, p = 0.01). Respiratory (n = 41, 39%) and bloodstream infections (n = 38, 36%) predominated, with primarily Gram-negative pathogens. 606 (84.7%) patients received an antimicrobial, amounting to 742 days of therapy per 1000 patient-days (DOTs). In multivariable models, receipt of high-dose steroids (≥ 30 mg prednisolone or equivalent) or tocilizumab was significantly associated with increased antimicrobial consumption (+ 5.5 DOTs, 95%CI 3.4–7.7 days) but not secondary infection (HR 0.56, 95%CI 0.26–1.18).ConclusionsBacterial and fungal infections in severe COVID-19 were uncommon. Receipt of steroids or tocilizumab was independently associated with antimicrobial consumption despite its lack of association with secondary infection. These findings should galvanise efforts to promote antimicrobial stewardship in patients with COVID-19.

In-hospital cardiac arrest due to sepsis – Aetiologies and outcomes in a Swedish cohort study

ObjectivesAwareness of causes of cardiac arrest is essential to prevent them. A recent review found that almost every sixth in-hospital cardiac arrest is caused by infection. Few studies have explored how infections cause cardiac arrest. AimTo describe the features, mechanisms and outcome of sepsis-related cardiac arrests. Material and methodsAll patients ≥18 years who suffered a cardiac arrest at Karolinska University Hospital between 2007 and 2022 with sepsis as the primary cause were included. Data were collected the Swedish Registry for Cardiopulmonary Resuscitation and medical records. The primary outcome was survival to discharge. ResultsOut of 2,327 in-hospital cardiac arrests, 5% (n = 123) suffered it due to sepsis, and 17% (21) survived to hospital discharge. Two thirds of patients were admitted to the hospital due to sepsis and suffered their cardiac arrest after a median of four days. About half (n = 59) had deranged vital signs before the event. Most were witnessed in general wards. In all, 47% (n = 58) had asystole and 24% (n = 30) as the first heart rhythm. The respiratory tract was the most common source of infection. Most patients were undergoing antibiotic therapy and one third had a positive microbiological culture with mixed gram-positive bacteria or Escherichia coli in the urine. ConclusionOur results suggest that sepsis is an uncommon and not increasing cause of in-hospital cardiac arrest and its outcome is in line with other non-shockable cardiac arrests. Deranged respiratory and/or circulatory vital signs precede the event.

The use of probabilistic graphical models in pediatric sepsis: a feasibility and scoping review.

Recent research has demonstrated that machine learning (ML) has the potential to improve several aspects of medical application for critical illness, including sepsis. This scoping review aims to evaluate the feasibility of probabilistic graphical model (PGM) methods in pediatric sepsis application and describe the use of pediatric sepsis definition in these studies. Literature searches were conducted in PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL+), and Web of Sciences from 2000-2023. Keywords included "pediatric", "neonates", "infants", "machine learning", "probabilistic graphical model", and "sepsis". A total of 3,244 studies were screened, and 72 were included in this scoping review. Sepsis was defined using positive microbiology cultures in 19 studies (26.4%), followed by the 2005's international pediatric sepsis consensus definition in 11 studies (15.3%), and Sepsis-3 definition in seven studies (9.7%). Other sepsis definitions included: bacterial infection, the international classification of diseases, clinicians' assessment, and antibiotic administration time. Among the most common ML approaches used were logistic regression (n=27), random forest (n=24), and Neural Network (n=18). PGMs were used in 13 studies (18.1%), including Bayesian classifiers (n=10), and the Markov Model (n=3). When applied on the same dataset, PGMs show a relatively inferior performance to other ML models in most cases. Other aspects of explainability and transparency were not examined in these studies. Current studies suggest that the performance of probabilistic graphic models is relatively inferior to other ML methods. However, its explainability and transparency advantages make it a potentially viable method for several pediatric sepsis studies and applications.

Positive Microbiological Culture among Patients with Infective Keratitis Visiting the Cornea Unit of a Tertiary Care Centre.

Keratitis is the infection and inflammation of the cornea. Microbial keratitis is a potentially sight-threatening corneal condition. The aim of this study was to find out the prevalence of positive microbiological culture among patients with infective keratitis visiting the Cornea Unit of a tertiary care centre. A descriptive cross-sectional study was conducted among patients with a clinical diagnosis of infective keratitis presenting to the Cornea Unit of a tertiary eye care centre from 16 October 2020 to 16 March 2021 after obtaining ethical approval from the Ethical Review Board. After slit-lamp examination, corneal scrapings were performed under aseptic conditions which were subjected to Gram stain, potassium hydroxide preparation and culture for bacterial and fungal pathogens. A convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval. Among 428 patients, 337 (78.73%) (73.24-84.33, 95% Confidence Interval) had a positive microbiological culture. A total of 213 (49.76%) of enrolled samples had a prior history of ocular trauma. Aspergillus species 68 (20.17%) and Streptococcus species 33 (9.79%) were the most common organisms isolated from fungal and bacterial corneal ulcers respectively. The prevalence of positive microbiological culture among patients with infective keratitis from this study is similar to the pattern reported from similar settings. corneal ulcer; keratitis; prevalence.