The impact of preoperative bacteriuria on the risk of periprosthetic joint infection after primary knee or hip replacement: a retrospective study with a 1-year follow up

ObjectivesPatients who undergo elective joint replacement are traditionally screened and treated for preoperative bacteriuria to prevent periprosthetic joint infection (PJI). More recently, this practice has been questioned. The purpose of this study was to determine whether preoperative bacteriuria is associated with an increased risk of PJI.MethodsPatients who had undergone a primary hip or knee replacement in a tertiary care hospital between September 2002 and December 2013 were identified from the hospital database (23 171 joint replacements, 10 200 hips, and 12 971 knees). The results of urine cultures taken within 90 days before the operation were obtained. Patients with subsequent PJI or superficial wound infection in a 1-year follow-up period were identified based on prospective infection surveillance. The association between bacteriuria and PJI was examined using a multivariable logistic regression model that included information on the operated joint, age, gender and the patients' chronic diseases.ResultsThe incidence of PJI was 0.68% (n = 158). Preoperative bacteriuria was not associated with an increased risk of PJI either in the univariate (0.51% versus 0.71%, OR 0.72, 95% CI 0.34–1.54) or in the multivariable (OR 0.82, 95% CI 0.38–1.77) analysis. There were no cases where PJI was caused by a pathogen identified in the preoperative urine culture. Results were similar for superficial infections.ConclusionsThere was no association between preoperative bacteriuria and postoperative surgical site infection. Based on these results, it seems that the preoperative screening and treatment of asymptomatic bacteriuria is not required.     

Origin and characteristics of haematogenous periprosthetic joint infection

ObjectivesRecognition of infectious origin of haematogenous periprosthetic joint infections (PJI) is crucial. We investigated the primary focus and characteristics of haematogenous PJI.MethodsConsecutive patients who presented with haematogenous PJI between 01/2010 and 01/2018 were retrospectively analysed. Haematogenous PJI was defined by diagnosis of infection ≥1 month after surgery, acute manifestation after a pain-free period and positive blood or prosthetic-site culture and/or evidence of distant infectious focus consistent with the pathogen. Fisher's exact, Student's t and Mann–Whitney U tests were used, as appropriate.ResultsA total of 106 episodes of PJI were included, involving 59 knee, 45 hip, one shoulder and one elbow prostheses. The median time from last surgery until haematogenous PJI was 47 months (range, 1–417 months). The pathogen was identified in 105 episodes (99%), including Staphylococcus aureus (n = 43), streptococci (n = 32), enterococci (n = 13), Gram-negative bacteria (n = 9) and coagulase-negative staphylococci (n = 8). Gram-negative bacteria were significantly more often found in hip joints than in knee joints. Blood cultures grew the pathogen in 43 of 70 episodes (61%). The primary infectious focus was identified in 72 episodes (68%) and included infections of intravascular devices or heart valves (22 episodes), skin and soft tissue (16 episodes), the oral cavity (12 episodes), urogenital (12 episodes) or gastrointestinal tract (seven episodes) and other sites (three episodes).ConclusionsIn acute PJI manifesting after a pain-free period, the haematogenous infection route should be considered and the primary infectious focus should be actively searched for. The cardiovascular system, skin and soft tissue, oral cavity, urogenital and gastrointestinal tracts were common origins of haematogenous PJI.     

Avoidance of intramedullary violation in computer-assisted total knee arthroplasty lowers the incidence of periprosthetic joint infection compared with conventional total knee arthroplasty: A propensity score matching analysis of 5342 cases

BackgroundConventional total knee arthroplasty (CONV-TKA) inevitably perturbs femoral medullary canal, disturbs medullary micro-architecture and increases blood loss and inflammatory responses. We hypothesized that avoidance of intramedullary violation may lower the incidence of periprosthetic joint infection (PJI). The aim of this study was to verify whether computer-assisted total knee arthroplasty (CAS-TKA) lowers the incidence of PJI as compared with CONV-TKA.MethodsA propensity score matching study of 5342 patients who underwent CAS-TKA (n = 1085) or CONV-TKA (n = 4257) for primary osteoarthritis of the knee from 2007 to 2015 in our institute was performed. Patients who underwent CAS-TKA were matched to those who received CONV-TKA at a 1:2 ratio according to demographics and comorbidities. PJI was defined according to the Musculoskeletal Infection Society diagnostic criteria from the 2013 International Consensus Meeting.ResultsAfter controlling potential risk factors, the use of CAS-TKA resulted in a lower incidence of PJI as compared with CONV-TKA [adjusted hazard ratio (HR), 0.42; 95% confidence interval (CI), 0.18–0.99]. The same trend in PJI reduction was observed with the usage of CAS-TKA under sensitivity testing [HR, 0.33; 95% CI, 0.12–0.95]. The cumulative incidence of PJI was lower in the CAS-TKA group than the CONV-TKA group (log-rank test, p = 0.013).ConclusionAvoidance of intramedullary violation during TKA may play a pivotal role in lowering the incidence of PJI. The use of CAS-TKA can reduce the incidence of PJI, with a better survival rate in terms of being free of PJI, as compared with CONV-TKA.Level of evidence III.     

Preoperative and perioperative risk factors,and risk score development for prosthetic joint infection due to Staphylococcus aureus: a multinational matched case-control study

ObjectivesWe aim to identify the preoperative and perioperative risk factors associated with post-surgical Staphylococcus aureus prosthetic joint infections (PJI) and to develop and validate risk-scoring systems, to allow a better identification of high-risk patients for more efficient targeted interventions.MethodsWe performed a multicenter matched case-control study of patients who underwent a primary hip and knee arthroplasty from 2014 to 2016. Two multivariable models by logistic regression were performed, one for the preoperative and one for perioperative variables; predictive scores also were developed and validated in an external cohort.ResultsIn total, 130 cases and 386 controls were included. The variables independently associated with S. aureus-PJI in the preoperative period were (adjusted OR; 95% CI): body mass index >30 kg/m² (3.0; 1.9 to 4.8), resident in a long-term care facility (2.8; 1.05 to 7.5), fracture as reason for arthroplasty (2.7; 1.4 to 5.03), skin disorders (2.5; 0.9 to 7.04), previous surgery in the index joint (2.4; 1.3 to 4.4), male sex (1.9; 1.2 to 2.9) and American Society of Anesthesiologists index score 3 to 4 (1.8; 1.2 to 2.9). The area under the receiver operating characteristic curve was 0.73 (95% CI 0.68 to 0.78). In perioperative model, the risk factors were the previous ones plus surgical antibiotic prophylaxis administered out of the first 60 minutes before incision (5.9; 2.1 to 16.2), wound drainage for >72 hours after arthroplasty (4.5; 1.9 to 19.4) and use of metal bearing material versus ceramic (1.9; 1.1 to 3.3). The area under the receiver operating characteristic curve was 0.78 (95% CI 0.72 to 0.83). The predictive scores developed were validated in the external cohort.DiscussionPredictive scores for S. aureus-PJI were developed and validated; this information would be useful for implementation of specific preventive measures.     

Concurrent systemic antibiotics at catheter insertion and intravascular catheter-related infection in the ICU: a post hoc analysis using individual data from five large RCTs

ObjectivesData on the impact of systemic antibiotics at the time of catheter insertion are scarce. Therefore, we assessed the association between concurrent antibiotic administration at insertion and short-term catheter-related infections.MethodsWe used individual data gathered from five large, randomized, controlled ICU trials. We analysed adult patients who required arterial, short-term central venous or dialysis catheter insertion in the ICU. The effect of antibiotics at insertion on major catheter-related infection (MCRI), catheter-related bloodstream infection (CRBSI) and colonization was estimated using multivariate marginal Cox and propensity score models.ResultsWe included 10 269 patients and 18 743 catheters from 36 ICUs. Antibiotic use was ongoing at the time of 11 361 catheter insertions (60.6%). After adjusting for well-known risk factors for intravascular catheter infection, we observed a similar risk for MCRI (HR 0.83, 95%CI 0.62–1.10, p 0.19) and CRBSI (HR 0.85, 95%CI 0.60–1.22, p 0.38) between the antibiotic and no-antibiotic groups. A confirmatory analysis using propensity score showed consistent results. No specific antibiotic subclasses reduced the risk of MCRI. Non-fermenting Gram-negative bacilli were more frequently observed in the antibiotic group.ConclusionsOngoing antibiotic administration at the time of catheter insertion was not associated with a decrease risk of catheter-related infections and should not be carried out for preventing such infections. Our results bring new insights to antimicrobial stewardship in critically ill patients and may direct empirical antimicrobial therapy if an intravascular catheter infection is suspected.     

Unicompartmental knee arthroplasty is associated with lower proportions of surgical site infection compared with total knee arthroplasty: A retrospective nationwide database study

BackgroundThis study aimed to clarify the association between types of knee arthroplasty (KA) (total knee arthroplasty (TKA) or unicompatmental knee arthroplasty (UKA)) and surgical site infection (SSI) with adjustment for various factors, using a Japanese national database.MethodsData on 181,608 patients who underwent unilateral primary KA for osteoarthritis from 2010 to 2017 were obtained from the Japanese Diagnosis Procedure Combination database. SSI was identified based on International Classification of Diseases 10th Revision codes. Deep SSI (i.e. periprosthetic joint infection (PJI)) was identified as SSI treated with surgical procedures. Multivariable logistic regression analyses for SSI and PJI were performed, in which dependent variables included types of KA, patient backgrounds (sex, age, body mass index (BMI), smoking status, comorbidities), and seasonality.ResultsEight percent of analyzed patients underwent UKA, while 92% underwent TKA. The proportions of SSI and PJI after UKA were 0.9% and 0.3%, respectively, both of which were lower than those after TKA (1.9% and 0.6%) (P < 0.001). Multivariable analyses showed lower proportions of SSI for UKA (adjusted odds ratio, 0.47; 95% confidence interval, 0.37–0.60; P < 0.001) and PJI (adjusted odds ratio, 0.47; 95% confidence interval, 0.34–0.65; P < 0.001) than TKA. Other factors associated with both SSI and PJI included male sex, BMI >30 kg/m², renal dysfunction and summer season.ConclusionUKA was associated with lower proportions of SSI and PJI than TKA. Surgeons should carefully consider the indication of UKA before performing TKA, especially in patients with knee unicompartmental osteoarthritis who are at a high risk for SSI or PJI.     

Microbiology of hip and knee periprosthetic joint infections: a database study

ObjectivesKnowledge of the microbiological aetiology of periprosthetic joint infection (PJI) is essential to its management. Contemporary literature from the United States on this topic is lacking. This study aimed to identify the most common microorganisms associated with types of arthroplasty, the timing of infection, and clues to polymicrobial infection.MethodsWe performed an analytical cross-sectional study of patients 18 years of age or older with hip or knee PJI diagnosed at our institution between 2010 and 2019. PJI was defined using the criteria adapted from those of the Musculoskeletal Infection Society. Cases included PJI associated with primary or revision arthroplasty and arthroplasty performed at our institution or elsewhere.ResultsA total of 2067 episodes of PJI in 1651 patients were included. Monomicrobial infections represented 70% of episodes (n = 1448), with 25% being polymicrobial (n = 508) and the rest (5%, n = 111) culture-negative. The most common group causing PJI was coagulase-negative Staphylococcus species (other than S. ludgunensis) (37%, n = 761). The distribution of most common organisms was similar regardless of arthroplasty type. The S. aureus complex, Gram-negative bacteria, and anaerobic bacteria (other than Cutibacterium species) were more likely to be isolated than other organisms in the first year following index arthroplasty (OR 1.7, 95%CI 1.4–2.2; OR 1.5, 95%CI 1.1–2.0; and OR 1.5, 95%CI 1.0–2.2, respectively). The proportion of culture-negative PJIs was higher in primary than revision arthroplasty (6.5% versus 3%, p 0.0005). The presence of a sinus tract increased the probability of the isolation of more than one microorganism by almost three-fold (OR 2.6, 95%CI 2.0–3.3).ConclusionsJoint age, presence of a sinus tract, and revision arthroplasties influenced PJI microbiology.     

Prosthetic joint infection of the knee - arthroscopic biopsy identifies more and different organisms than aspiration alone

BackgroundProsthetic joint infection (PJI) causes significant morbidity and mortality following knee replacement surgery. Identifying causative organisms and antibiotic sensitivities is critical in increasing the chance of infection eradication. This study investigated whether biopsy alone was superior to aspiration alone for serological diagnosis in PJI following knee replacement. Secondly, we investigated whether biopsy identifies the same or new/different microbiological flora as aspiration.MethodsSince December 2014, the Exeter Knee Reconstruction Unit (EKRU) has prospectively collated data regarding all PJIs referred from our local/regional network which have been reviewed via our Multi-Disciplinary Team (MDT). We identified and included consecutive patients from this MDT from Dec.2014-Mar.2020 and analysed their electronic records. Statistical analysis was performed using Stata.Results65/100 patients studied had both pre-operative aspiration and biopsy. 31/65 (48%) had positive aspiration and biopsies. No aspirate samples were positive with corresponding biopsies negative. In 19/65 (29%) of infection positive patients, biopsy identified new (7) or additional (12) organisms not identified by aspiration. Aspiration had a sensitivity of 70%, specificity of 88%, positive predictive value of 90.3% and negative predictive value of 64.7%. Biopsy had a sensitivity of 97.5%, specificity of 88%, positive predictive value of 92.9% and negative predictive value of 95.7%.ConclusionIn 29% of confirmed PJI cases, arthroscopic biopsy identified either additional organisms in a polymicrobial PJI when compared to aspiration, or new positive results when aspiration alone was negative. This study demonstrates the benefits of arthroscopic biopsy for serological diagnosis in cases of knee PJI and aids treatment planning.     

Protective effect of N-acetylcysteine in prosthetic joint infection: A nationwide population-based cohort study

PurposeThis nationwide population-based retrospective cohort study evaluated the protective effect of N-acetylcysteine against prosthetic joint infection after hip or knee joint replacement.MethodsPatients receiving N-acetylcysteine after hip or knee joint replacement between 2000 and 2015 were identified from the Taiwan National Health Insurance Research Database. Each patient receiving N-acetylcysteine was matched to four controls based on age, sex, and index year. All subjects were followed-up from the index date to December 31, 2015. The Cox proportional hazards regression model was used to assess the risk of prosthetic joint infection.ResultsA total of 1478 patients were included in the study group, and 5912 matched subjects not receiving N-acetylcysteine were included in the control group. After adjusting for age, sex, insured premium, comorbidities, and immunosuppressive agent use, no significant difference in the risk of prosthetic joint infection was found between the two groups. A higher N-acetylcysteine dose (>360 cumulative defined daily dose) significantly decreased the risk of prosthetic joint infection (adjusted hazard ratio = 0.891; 95% confidence interval = 0.599–0.989; p = 0.042). The protective effect of N-acetylcysteine was observed only in the group of prosthetic joint infection within 5 years (adjusted hazard ratio = 0.801; 95% confidence interval = 0.581–0.980; p = 0.040).ConclusionsHigh cumulative dose of N-acetylcysteine (>360 cumulative defined daily dose) can effectively reduce the risk of prosthetic joint infection in patients undergoing knee or hip joint replacement surgery within 5 years.     

Nanopore 16S amplicon sequencing enables rapid detection of pathogen in knee periprosthetic joint infection

ObjectivesWe investigated whether nanopore 16S amplicon sequencing is capable of bacterial identification in patients with knee prosthetic joint infection (PJI), and we compared its efficacy with conventional culture studies.MethodsIn total, 36 patients who had clinical manifestation suspected of PJI were enrolled in this study. To begin, synovial fluids were aspirated from the affected knee using aseptic technique and tissues specimens were obtained during the surgery. Next, DNA was extracted from the synovial fluid or tissues, and 16S rDNA PCR was performed. In PCR positive cases, nanopore amplicon sequencing was then performed for up to 3 h. The results of amplicon sequencing were compared to those of conventional culture studies.ResultsOf the 36 patients enrolled, 22 were classified as true infections according to the MSIS criteria whereas 14 were considered uninfected. Among the 22 PJI cases, 19 cases were culture positive (CP-PJI) while three cases were culture negative (CN-PJI). In 14 of 19 (73.7 %) CP- PJI cases, 16S sequencing identified concordant bacteria with conventional culture studies with a significantly shorter turnaround time. In some cases, nanopore 16S sequencing was superior to culture studies in the species-level identification of pathogen and detection of polymicrobial infections. Altogether, in the majority of PJI candidate patients (32 of 36, 88.9 %), 16S sequencing achieved identical results to cultures studies with a significantly reduced turnaround time (100.9 ± 32.5 h vs. 10.8 ± 7.7 h, p < 0.001).ConclusionsNanopore 16S sequencing was found to be particularly useful for pathogen identification in knee PJI. Although the sensitivity was not superior to culture studies, the nanopore 16S sequencing was much faster, and species-level identification and detection of polymicrobial infections were superior to culture studies.     

Time to antibiotic administration and patient outcomes in community-acquired pneumonia: results from a prospective cohort study

ObjectivesCommunity-acquired pneumonia (CAP) is a frequently occurring disease linked to high mortality and morbidity. Previous studies indicated that the administration of antibiotics within 4 hrs of admission can improve key patient outcomes associated with CAP, such as mortality and time to clinical stability. However, the results have been heterogeneous and may not be applicable to all healthcare settings. Therefore, we designed a cohort study to estimate the impact of timely antibiotic administration on outcomes in patients admitted with CAP.MethodsThe impact of antibiotic administration within 4 hrs of admission and other covariates were estimated for 30-day mortality, stability within 72 hrs, 30-day readmission and time to discharge, using multivariable regression models. Sensitivity analyses were performed on a subset of patients with the most severe CAP and a propensity score matched cohort.ResultsIn total, 2264 patients were included. Of these, 273 (12.1%) died within 30 days of admission, 1277 (56.4%) were alive and stable within 72 hrs and 334 (14.8%) were discharged alive and readmitted within 30 days. Median length of hospital stay was 5 days (interquartile range 3–8). In all models, the administration of antibiotics within 4 hrs of admission had no significant effect on the outcomes. The adjusted odds ratios (OR) derived from the multivariable models for 30-day mortality, stability within 72 hrs and 30-day readmission were 1.01 (95% confidence interval (CI) 0.76; 1.33), 0.88 (95% CI 0.74; 1.05) and 1.05 (95% CI 0.82; 1.34). The adjusted hazard ratio (HR) for time to discharge was 1.00 (95% CI 0.91; 1.10).DiscussionA strict 4-hr threshold for antibiotic administration in all patients admitted with CAP is not reasonable. Instead, our results suggested that patients should be triaged and prioritized according to age, comorbidities, clinical condition and pneumonia severity.     

Antibiotics versus no therapy in kidney transplant recipients with asymptomatic bacteriuria (BiRT): a pragmatic,multicentre, randomized,controlled trial

ObjectivesMany transplant physicians screen for and treat asymptomatic bacteriuria (ASB) during post-kidney-transplant surveillance. We investigated whether antibiotics are effective in reducing the occurrence of symptomatic urinary tract infection (UTI) in kidney transplant recipients with ASB.MethodsWe performed this multicentre, randomized, open-label trial in kidney transplant recipients who had ASB and were ≥2 months post-transplantation. We randomly assigned participants to receive antibiotics or no therapy. The primary outcome was the incidence of symptomatic UTI over the subsequent 12 months.ResultsOne hundred and ninety-nine kidney transplant recipients with ASB were randomly assigned to antibiotics (100 participants) or no therapy (99 participants). There was no significant difference in the occurrence of symptomatic UTI between the antibiotic and no-therapy groups (27%, 27/100 versus 31%, 31/99; univariate Cox model: hazard ratio 0.83, 95%CI: 0.50–1.40; log-rank test: p 0.49). Over the 1-year study period, antibiotic use was five times higher in the antibiotic group than in the no-therapy group (30 antibiotic days/participant, interquartile range 20–41, versus 6, interquartile range 0–15, p < 0.001). Overall, 155/199 participants (78%) had at least one further episode of bacteriuria during the follow-up. Compared with the participant's baseline episode of ASB, the second episode of bacteriuria was more frequently caused by bacteria resistant to clinically relevant antibiotics (ciprofloxacin, cotrimoxazole, third-generation cephalosporin) in the antibiotic group than in the no-therapy group (18%, 13/72 versus 4%, 3/83, p 0.003).ConclusionsApplying a screen-and-treat strategy for ASB does not reduce the occurrence of symptomatic UTI in kidney transplant recipients who are more than 2 months post-transplantation. Furthermore, this strategy increases antibiotic use and promotes the emergence of resistant organisms.     

Urinary culture sensitivity after a single empirical antibiotic dose for upper or febrile urinary tract infection: A prospective multicentre observational study

ObjectivesUrinary culture sensitivity after antibiotics administration is unknown. This study aimed to describe the diagnostic sensitivity of urine cultures from patients' first, second, and third micturition samples after a single dose of empirical antibiotics given for upper and/or febrile urinary tract infections, as well as searched for factors influencing diagnostic sensitivity over time.MethodsWe collected consecutive urine samples from adult patients with an upper or febrile urinary tract infection diagnosed at four secondary hospital emergency rooms. One sample was collected before a first dose of empirical antibiotic treatment and up to three samples were collected from consecutive postadministration micturition. The main outcome was the number of positive cultures growing uropathogens with ≥10³ colony forming units (CFUs) for men and ≥10⁴ for women. Identical analyses were performed for any identified CFU and ≥10⁵ CFU cut-off points. Time between antibiotic administration and first negative urinary culture was noted, which could have been at the time of any of the three postantibiotic urine samples. We used a Cox regression analysis for age- and sex-adjusted analyses.ResultsA total of 86 of 87 patients' preantibiotic cultures (99%) were positive compared with 26 of 75 (35%; p < 0.001), 15 of 50 (30%; p < 0.001), and 1 of 15 (7%; p < 0.001) of the first, second, and third postantibiotic samples, respectively, and missing 14 of 21 (67%), 13 of 17 (76%), and 7 of 7 (100%) of uropathogens with antibiotic resistance, respectively. The times needed for 25%, 50%, and 75% of cultures to be negative were 1.5, 2.9, and 9 hours, respectively, after antibiotic administration. Older age, male sex, non-Escherichia coli pathogens, urinary tract disease, comorbidity burdens, and urinary catheters prolonged time to negative culture, but were not significantly associated after adjustment. Uropathogens were found at ≥10⁵ CFU in 15 of 75 (20%), 7 of 50 (14%), and 0 of 15 (0%) of the three postantibiotic micturition samples, respectively, and in any identified CFU in 48 of 75 (64%), 23 of 50 (46%), and 1 of 15 (7%), respectively.ConclusionUrinary culture sensitivity decreases rapidly after administering antibiotics.     

Appropriate antibiotic therapy is a predictor of outcome in patients with Stenotrophomonas maltophilia blood stream infection in the intensive care unit

Background/purposeThe study was to assess the relationship between antibiotic therapy and the outcome in intensive care unit (ICU) patients with Stenotrophomonas maltophilia bloodstream infection (BSI).MethodsICU patients with monomicrobial S. maltophilia BSI from January 2004 to December 2019 were included and divided into two groups—those with- and without appropriate antibiotic therapy after BSI—for comparison. The primary outcome was the relationship between appropriate antibiotic therapy and 14-day mortality. The secondary outcome was the influence of different antibiotic therapies: levofloxacin- and trimethoprim–sulfamethoxazole (TMP/SMX)-containing regimens, on 14-day mortality.ResultsA total of 214 ICU patients were included. Patients received appropriate antibiotic therapy (n = 133) after BSI had a lower 14-day mortality than those (n = 81) without appropriate antibiotic therapy (10.5% vs. 46.9%, p < 0.001). No difference on 14-day mortality between groups of patients by time of appropriate antibiotic therapy was observed (p > 0.05). After a propensity score matching, the results is consistent that 14-day mortality were lower in patients with appropriate antibiotic therapy than those without appropriate antibiotic therapy (11.5% vs. 39.3%, p < 0.001). Among patients with S. maltophilia BSI receiving appropriate antibiotic therapy, there was a trend levofloxacin-containing regimens is associated with lower mortality than TMP/SMX-containing regimens (HR 0.233, 95% CI 0.050–1.084, p = 0.063).ConclusionAppropriate antibiotic therapy was associated with decreased 14-day mortality in ICU patients with S. maltophilia BSI regardless of time. Levofloxacin-containing regimens may be better choice than TMP/SMX -containing regimens in treating ICU patients with S. maltophilia BSI.     

Evaluation of antibiotic use in Pediatric Intensive Care Unit of a developing country

Background:Pediatric Intensive Care Unit (PICU) patients are often prescribed antibiotics with a low threshold in comparison to patients elsewhere. Irrational antibiotics use can lead to rapid emergence of drug resistance, so surveillance of their use is important.Objectives:To evaluate the use of antibiotics in relation to bacteriological findings in PICU of a Tertiary Hospital.Methods:Retrospective review of medical records of all children (age 1 month–16 years) admitted in our closed multidisciplinary-cardiothoracic PICU from January to June 2013 was performed, after approval from Ethical Review Committee. For each antibiotic, indication (prophylactic, empiric, therapeutic) and duration of use were recorded. All diagnoses of infections were recorded according to diagnostic criteria of IPSCC 2005. Results are presented as frequency and percentages and median with inter quartile range using SPSS version 19.Results:All of the total 240 patients admitted in PICU during the study period received antibiotics: 43% (n = 104) prophylactically, 42% (n = 102) empirically, and 15% (n = 15) therapeutically. Median number of antibiotic use per patient in PICU was 3, with range of 1–7. 25% received 1 antibiotic, 23% received 2 antibiotics, 29% received 3 antibiotics, and rest received ≥4 antibiotics. Most commonly used antibiotics were cefazolin, meropenem, vancomycin and ceftriaxone, and most frequently used combination was meropenem and vancomycin. In majority of the cases, (70%) empiric antibiotic combinations were stopped in 72 h.Conclusion:This is the first report of antibiotics use in PICU from our country, which shows that antibiotics are prescribed universally in our PICU. Strategies to assess the need for antibiotic use are needed.     

Periprosthetic joint infection after primary TKA in the medicare population: How frequently are patients revised at a different hospital?

BackgroundPeriprosthetic infection (PJI) after total knee arthroplasty (TKA) places a significant burden on hospitals. We sought to describe the proportion of patients undergoing revision for PJI at a different hospital within one year of primary TKA and whether patient characteristics or hospital volume were associated with this change.MethodsMedicare data from 2005 to 2014 was retrospectively reviewed using PearlDiver. All patients over 64 years undergoing revision for PJI within one year of primary TKA were stratified by the revision occurring within 90 days. Hospitals were grouped by annual TKA volume as Low (<50), Medium (51–100), High (101–200), and Very High (>200). Associations of patient characteristics and hospital volume with revision at a different hospital were assessed using Chi-squared tests and Somers' D.ResultsOf 8,337 patients undergoing revision within 90 days of TKA, 1,370 (16%) were revised at a different hospital. Changing hospitals was associated with having primary TKA at a lower volume hospital (24% for low, 15% medium, 12% high, and 12% very high; P < 0.001). Of 7,608 patients undergoing revision between 91 and 365 days, 1,110 (15%) were revised at a different hospital. Changing hospitals was associated with having primary TKA at a lower volume hospital (26% for low, 14% medium, 10% high, and 9% very high; P < 0.001). Changing hospitals was not associated with sex or age.ConclusionPatients frequently undergo revision for PJI at a different hospital, even within 90 days of TKA. Further research is needed to understand these implications of this care pathway shift.     

Decreased susceptibility to chlorhexidine and prevalence of disinfectant resistance genes among clinical isolates of Staphylococcus epidermidis

Staphylococcus epidermidis is a versatile agent, being both a commensal and a nosocomial pathogen usually with an opportunistic role in association with implanted foreign body materials. Pre‐operative antiseptic preparation is an important strategy for reducing the risk of complications such as surgical site infection (SSI). Currently, the most widely used antiseptics are alcohols, quaternary ammonium compounds (QACs), and the bisbiguanide chlorhexidine. Occurrence of resistance to the latter agent has drawn increasing attention. The aim of this study was to investigate if decreased susceptibility to chlorhexidine among S. epidermidis was present in our setting, a Swedish university hospital. Staphylococcus epidermidis (n = 143), retrospectively collected, were obtained from prosthetic joint infections (PJI) (n = 61), post‐operative infections after cardiac surgery (n = 31), and the skin of the chest after routine disinfection prior to cardiac surgery (n = 27). In addition, 24 commensal isolates were included. Minimum inhibitory concentration (MIC) of chlorhexidine was determined on Mueller Hinton agar plates supplemented with serial dilutions of chlorhexidine. Five QAC resistance genes, qacA/B, smr, qacH, qacJ, and qacG, were detected using PCR. Decreased susceptibility to chlorhexidine was found in 54% of PJI isolates, 68% of cardiac isolates, 21% of commensal isolates, and 7% of skin isolates from cardiac patients, respectively. The qacA/B gene was present in 62/143 isolates (43%), smr in 8/143 (6%), and qacH in one isolate (0.7%). The qacA/B gene was found in 52% of PJI isolates, 61% of cardiac isolates, 25% of commensal isolates, and 19% of the skin isolates. In conclusion, decreased susceptibility to chlorhexidine, as well as QAC resistance genes, were prevalent among S. epidermidis isolates associated with deep SSIs.