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AIM: This study investigated the compliance with a guideline-based antibiotic regimen on the outcome of patients surgically treated for a fracture-related infection (FRI). METHOD: In this international multicenter observational study, patients were included when diagnosed with an FRI between 2015 and 2019. FRI was defined according to the FRI consensus definition. All patients were followed for at least one year. The chosen antibiotic regimens were compared to the published guidelines from the FRI Consensus Group and correlated to outcome. Treatment success was defined as the eradication of infection with limb preservation. RESULTS: A total of 433 patients (mean age 49.7 ± 16.1 years) with FRIs of mostly the tibia (50.6%) and femur (21.7%) were included. Full compliance of the antibiotic regime to the published guidelines was observed in 107 (24.7%) cases. Non-compliance was mostly due to deviations from the recommended dosing, followed by the administration of an alternative antibiotic than the one recommended or an incorrect use or non-use of rifampin. Non-compliance was not associated with a worse outcome: treatment failure was 12.1% in compliant versus 13.2% in non-compliant cases (p = 0.87). CONCLUSIONS: We report good outcomes in the treatment of FRI and demonstrated that minor deviations from the FRI guideline are not associated with poorer outcomes. ispartof: JOURNAL OF INFECTION vol:86 issue:3 pages:227-232 ispartof: location:England status: published

Objectives: Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) is a widely used method for bacterial species identification. Incomplete databases and mass spectral quality (MSQ) still represent major challenges. Important proxies for MSQ are the number of detected marker masses, reproducibility, and measurement precision. We aimed to assess MSQs across diagnostic laboratories and the potential of simple workflow adaptations to improve it.Methods: For baseline MSQ assessment, 47 diverse bacterial strains, which are challenging to identify by MALDI-TOF MS, were routinely measured in 36 laboratories from 12 countries, and well-defined MSQ features were used. After an intervention consisting of detailed reported feedback and instructions on how to acquire MALDI-TOF mass spectra, measurements were repeated and MSQs were compared.Results: At baseline, we observed heterogeneous MSQ between the devices, considering the median number of marker masses detected (range = [2–25]), reproducibility between technical replicates (range = [55%–86%]), and measurement error (range = [147 parts per million (ppm)–588 ppm]). As a general trend, the spectral quality was improved after the intervention for devices, which yielded low MSQs in the baseline assessment as follows: for four out of five devices with a high measurement error, the measurement precision was improved (p-values Discussion: We have identified simple workflow adaptations, which, to some extent, improve MSQ of poorly performing devices and should be considered by laboratories yielding a low MSQ. Improving MALDI-TOF MSQ in routine diagnostics is essential for increasing the resolution of bacterial identification by MALDI-TOF MS, which is dependent on the reproducible detection of marker masses. The heterogeneity identified in this external quality assessment (EQA) requires further study.

Background Evaluation of the diagnostic value of routine chest tube tip culture for detection of postoperative infection after surgery for noninfectious lung disease. Methods Included subjects were patients who underwent lung surgery between January 1st 2013 and January 1st 2018 in University Medical Centre Utrecht and of whom a chest tube tip was cultured. Postoperative outcomes included pneumonia, surgical site infection, and empyema within 30 days after surgery. Univariable analysis for diagnostic accuracy of chest tube tip culture results predicting these postoperative outcomes was performed, as well as multivariable analysis using penalized firth logistic regression. Results Patients developed one or more postoperative infections in 42 out of 210 (20%) lung surgeries. Pneumonia, surgical site infection, and empyema were found in 36 (17%), 8 (4%), and 2 (1%) cases respectively. Chest tube tip culture had a sensitivity of 31%, a specificity of 83%, a positive predictive value of 32%, and a negative predictive value of 83% for postoperative infections. In the subgroup of patients who did not have evidence of postoperative infection at the time of chest tube removal, the drain tip culture’s positive and negative predictive value changed to 18% and 92% respectively. Adding additional variables to chest tube tip culture in a prediction model resulting in only limited improvement in diagnostic performance. Conclusions We found insufficient diagnostic performance to support the practice of routine chest tube tip culture after surgery for noninfectious lung disease. Therefore, routine chest tube tip culture is not advisable and should be omitted to unburden the healthcare process and prevent low value care together with extra costs.

To the Editor,Enterococcus faecium clonal spread is well established in hospitals in many countries. Over the last 10 years, the clonal spread of E. faecium also emerged in Dutch hospitals. Previou...

Pseudomonas aeruginosa isolates from Cystic fibrosis (CF) patients are growing slowly, and frequently rendering automated susceptibility testing unsuitable. Colistin is an important antibiotic for treatment of P. aeruginosa infections. Broth microdilution is the only EUCAST endorsed antimicrobial susceptibility test for colistin. The VIZION™ device aids in reading broth microdilution plates and allows safe data transfer to laboratory information systems. In this study, reproducibility between visual MIC readout and readout, employing the VIZION™ device was assessed in susceptibility testing of colistin and beta-lactam antibiotics in P. aeruginosa isolates from CF patients.Fifty-six unique P. aeruginosa isolates were derived from respiratory secretions of CF patients. Susceptibility testing was performed using commercially available microdilution plates. MIC readout by VIZION™ was compared to visual readout aided by a mirror (reference test).Pseudomonas aeruginosa isolates displayed significantly slower growth rates compared to quality control isolates. Colistin exact MIC agreement between VIZION™ and visual readout after 24 and 48 h incubation, respectively, was 82% and 95%, essential MIC agreement was 98% and 100%, categorical agreement was 98% and 98% and reliability (weighted kappa) was 0.95 (95% CI = 0.91-0.99) and 0.99 (95% CI = 0.97-1.00). For all five antibiotics, the total number of errors (using VIZION™, in comparison with visual readout) decreased from 15 (5%) to 10 (4%) after 24 and 48 h incubation, respectively.VIZION™ readout reproducibly determines MIC values in comparison with visual readout after 24 h of incubation. Reproducibility between the VIZION™ and visual readout increases after prolonged incubation of 48 h.

Introduction: Debridement, antibiotics and implant retention (DAIR) procedures are effective treatments for acute postoperative or acute hematogenous periprosthetic joint infections. However, literature reporting on the effectiveness of DAIR procedures performed after a one- or two-stage revision because of a prosthetic joint infection (PJI) (PJI-related revision arthroplasty) is scarce. The aim of this study is to retrospectively evaluate the infection control after 1 year of a DAIR procedure in the case of an early postoperative infection either after primary arthroplasty or after PJI-related revision arthroplasty. Materials and methods: All patients treated with a DAIR procedure within 3 months after onset of PJI between 2009 and 2017 were retrospectively included. Data were collected on patient and infection characteristics. All infections were confirmed by applying the Musculoskeletal Infection Society (MSIS) 2014 criteria. The primary outcome was successful control of infection at 1 year after a DAIR procedure, which was defined as the absence of clinical signs, such as pain, swelling, and erythema; radiological signs, such as protheses loosening; or laboratory signs, such as C-reactive protein (CRP) () with no use of antibiotic therapy. Results: Sixty-seven patients were treated with a DAIR procedure (41 hips and 26 knees). Successful infection control rates of a DAIR procedure after primary arthroplasty (n=51) and after prior PJI-related revision arthroplasty (n=16) were 69 % and 56 %, respectively (p=0.38). The successful infection control rates of a DAIR procedure after an early acute infection (n=35) and after a hematogenous infection (n=16) following primary arthroplasty were both 69 % (p=1.00). Conclusion: In this limited study population, no statistically significant difference is found in infection control after 1 year between DAIR procedures after primary arthroplasty and PJI-related revision arthroplasty.

Background: Diagnosis of periprosthetic joint infection (PJI) can be troublesome. Sonication can be a helpful tool in culturing bacteria that are difficult to detect with standard tissue cultures. Aim of this study is to evaluate the clinical importance of our standardized sonication protocol in detecting periprosthetic joint infection.Materials and methods: All patients with revision surgery of a hip or knee prosthesis between 2011 and 2016 were retrospectively reviewed and divided in two groups: clinically suspected of infection or not suspected of infection. For both tissue culture and implant sonication, calculations of sensitivity and specificity were performed. Clinical relevance of sonication was evaluated by calculating in which percentage of patients' sonication influenced clinical treatment.Results: 226 patients with revision of a total hip prosthesis (122 patients) or a total knee prosthesis (104 patients) were included. Sensitivity of perioperatively taken tissue cultures was 94.3% and specificity was 99.3%. For sonication sensitivity was 80.5% and specificity was 97.8%.In the infection group eight patients (9%) with only one positive tissue culture and a positive sonication fluid culture with the same pathogen were found.Interpretation: Although sensitivity and specificity of sonication was lower compared to tissue cultures, periprosthetic joint infection could only be established in 8 patients (9%) suspected of infection because of a positive result of the sonication fluid culture.Sonication leads to clinically relevant changes in treatment and seems therefore to be a helpful diagnostic tool in clinical practice.

Seven weeks after being kicked in the face by a cow, a 34-year-old male patient developed a posttraumatic mycobacterial lymphadenitis. A rapidly growing mycobacterial isolate cultured from a surgically drained lymphadenitis pus specimen was identified as Mycobacterium smegmatis by matrix-assisted laser desorption/ionization mass spectrometry and a combination of ITS-, hsp65-, and 16S rRNA-DNA sequence analysis, but as Mycobacterium fortuitum complex using the commercial INNO-LiPA Mycobacteria v2 line probe assay. As it is unclear if the misidentification of this strain is an exception, more research is required.

Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) identification (ID) of Candida yeast isolates is fast and reliable, but the optimal workflow is debated ([1][1], [2][2]). Two different steel target plates are available for the Microflex system (Bruker

Summary A commercially available enzyme-linked immunoelectrotransfer blot originally intended for diagnosis of cysticercosis was evaluated for echinococcosis diagnosis, because a characteristic band pattern – different from the specific cysticercosis pattern – was observed in sera from patients with echinococcosis. This band pattern was observed in 29 (78%) of 37 parasitologically proven cystic echinococcosis patients. Specificity of these bands was 100% for echinococcosis, when tested with 75 control sera.

Identification of Neisseria gonorrhoeae by the Bruker matrix-assisted laser desorption ionization−time of flight mass spectrometry (MALDI-TOF MS) system may be affected by “B consistency categorization.” A supplementary database of 17 N. gonorrhoeae main spectra was constructed. Twelve of 64 N. gonorrhoeae identifications were categorized with B consistency, which disappeared using the supplementary database. Database extension did not result in misidentification of Neisseria meningitidis .

Item does not contain fulltext A case series of 14 patients with Raoultella bacteremia was compared with 28 Klebsiella oxytoca and 28 Klebsiella pneumoniae bacteremia cases. Forty-three percent of Raoultella bacteremia cases were associated with biliary tract disease, compared to 32% and 22% of patients with K. oxytoca and K. pneumoniae bacteremia, respectively.

A 69-year-old male from the province of Brabant, the Netherlands, was referred to a tertiary care hospital for a cardiac surgical intervention for severe aortic valve insufficiency due to aortic valve endocarditis. His medical history showed chronic cardiovascular disease, including hypertension and

Item does not contain fulltext Ninety-nine clinical isolates previously identified as Klebsiella oxytoca were evaluated using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Eight isolates were identified as Raoultella spp., being 5 Raoultella spp. and 3 K. oxytoca, by 16S rRNA sequencing. These isolates were correctly identified by applying the 10% differential rule for the MALDI-TOF MS score values. This approach might be useful to discriminate Raoultella species from K. oxytoca. 01 april 2013

Item does not contain fulltext BACKGROUND: Urinary tract infections (UTIs) are common infections in the community and the hospital. With increasing antimicrobial resistance, specifically in the Gram-negative uropathogens, reliable, rapid antimicrobial susceptibility data would be useful to guide antimicrobial treatment. Direct antimicrobial susceptibility testing (DST) of urine with microscopic evidence of Gram-negative bacterial infection and its clinical significance was investigated in this study. METHODS: DST was performed by Kirby-Bauer disk diffusion method using undiluted urine as a non-standardized inoculum. Urine specimens with Gram-negative bacteria on microscopy were included. DST results from growth of Gram-negative bacteria were compared to routine antimicrobial susceptibility testing by Phoenix automated system (AST). Errors were scored as 'very major error' if susceptible by DST but resistant by AST and as 'major error' if resistant by DST but susceptible by AST. All other discrepancies were defined as 'minor error'. Discrepancies were resolved by determination of minimum inhibitory concentrations (MICs) using Etests. After discrepancy analysis, errors were scored as above using the Etest as the reference method. For analysis, specimens were divided into 3 categories: category A: 1 isolate found by DST as well as by routine culture; category B: 1 isolate detected by DST, but more than 1 isolate found on routine culture; category C: more than 1 isolate found by both DST and routine culture. The clinical significance of DST was determined prospectively by investigating the potential impact of DST on antimicrobial therapy. RESULTS: One hundred and sixteen urine specimens were included. For DST and AST there was agreement in 96% of 1152 comparisons in category A (n = 100), 88% of 41 comparisons in category B (n = 4), and 88% of 110 comparisons in category C (n = 12). The 64 discrepancies included 18 very major errors, 7 major errors, and 39 minor errors. Eight very major errors and 11 minor errors were not investigated because the isolates were not available. After Etest MIC determination for the 45 remaining discrepancies, DST showed 1 very major error, 1 major error, and 8 minor errors in category A, none in category B, and 5 major errors and 4 minor errors in category C. Antimicrobial therapy for UTI was prescribed for 53 patients. For 4 patients (8%) therapy was adjusted based on DST because of antimicrobial resistance and for 12 patients (23%) antimicrobial treatment could have been streamlined. CONCLUSIONS: DST on urine is reliable in monobacterial Gram-negative infections. With increasing antimicrobial resistance, DST can make an important contribution to patient management and reduce the use of broad-spectrum antimicrobials.

Answer: Q fever endocarditis. The diagnosis was Q fever endocarditis of a native aortic valve. Figure 1 in the photo quiz shows Coxiella burnetii as numerous small Gram-variable (Gram-negative as well as Gram-positive) coccobacilli. The diagnosis of C. burnetii endocarditis was established by

We present descriptions of two human Mycobacterium microti infections: one of a patient with pulmonary disease and one of a patient with osteomyelitis of the hip. Both patients had acid-fast bacilli and a positive Mycobacterium tuberculosis complex PCR from clinical specimens, but mycobacterial cultures remained negative. The microbiological diagnosis was established by molecular methods.

Item does not contain fulltext Here, we report the first isolation of Wautersiella falsenii from the urine of an infant with a complicated urinary tract infection. W. falsenii was correctly identified by matrix-assisted laser desorption ionisation time of flight mass spectrometry. The identification was confirmed by 16S polymerase chain reaction. Susceptibility test results of this isolate are reported. Ciprofloxacin treatment resulted in clinical and microbiological improvement.

Expansion and differentiation of alloantigen-reactive CD8(+) T cells in mixed lymphocyte cultures was followed by measurement of the loss of carboxyfluorescein diacetate succinimidyl ester (CFSE) fluorescence of responder cells. Proliferation of CD8(+) T cells became detectable on day 4 of culture and, 2 days later,60% of the CD8(+) T cells in culture were dividing alloreactive lymphocytes. In parallel with expansion, CD8(+) T-cell differentiation was initiated, as evidenced by an increase in the number of CD45RA(-) and CD27(-) T cells and acquisition of the ability to produce interferon-gamma after restimulation with the specific alloantigen. Finally, although short-term stimulation and measurement of intracellular cytokine production allowed visualization of alloreactive CD8(+) T cells expanded in vitro, this procedure did not detect circulating alloreactive CD8(+) T cells activated in vivo in recipients of allogeneic kidney grafts.

Contains fulltext : 87887pub.pdf (Publisher’s version ) (Closed access) PURPOSE: To evaluate the clinical characteristics, bacterial culture, and visual outcome of patients with acute endophthalmitis after cataract surgery. DESIGN: Retrospective consecutive interventional case series. METHODS: Clinical notes from patients treated for acute endophthalmitis after cataract surgery in a single center from 1996 to 2006 were reviewed. Patients with less than 1 month of follow-up and missing bacterial cultures were excluded. Vitreous biopsy or primary vitrectomy followed by intravitreal injection of vancomycin and ceftazidime (+/- prednisolone) was performed. Main outcome measures were bacterial culture and final visual acuity. RESULTS: Bacterial cultures (total 250 cases) showed bacterial growth in 166 cases (66.4%). From these 166 cultures, 89 (53.6%) revealed gram-positive coagulase-negative, 63 (38.0%) other gram-positive, 10 (6.0%) gram-negative, and 4 (2.4%) polymicrobial cultures. Vitreous biopsy with intravitreal antibiotics injection was performed in 225 (90.0%) of cases. Primary vitrectomy with intravitreal antibiotics was performed in 25 eyes (10.0%). Final visual acuity >/=0.5 was achieved in 129 (51.6%) of all cases, 54 (60.7%) of the 89 gram-positive coagulase-negative cultures, 20 (31.7%) of the 63 other gram-positive cultures, 5 (50.0%) of the 10 gram-negative cultures, and 9 (45.0%) of the 20 Staphylococcus aureus cultures. There was no additional effect for treatment by primary vitrectomy or intravitreal prednisolone. CONCLUSIONS: Treatment outcome after endophthalmitis is highly dependent on the causative organism. Treatment outcomes for gram-negative bacteria and S. aureus may be better than previously reported. Prompt treatment of endophthalmitis remains essential and the role of complete primary vitrectomy remains subject to debate. 01 maart 2010