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Aims of the Study: The goal of this descriptive study was to assess the performance as well as the extent of the clinical impact of rapid automated antimicrobial susceptibility testing in patients with bacteraemia due to Enterobacterales. We also aimed to analyse how rapid automated antimicrobial susceptibility testing influences clinical decision-making., Methods: This single-centre study conducted at the University Hospital of Zurich included data from all consecutive patients with Enterobacterales bacteraemia from November 2019 to October 2020. There was no control group. The primary outcome was the effect of rapid automated antimicrobial susceptibility testing on antibiotic therapy (no adjustment, escalation to a broader-spectrum antibiotic or de-escalation to a narrower-spectrum antibiotic). Rapid automated antimicrobial susceptibility testing results were further compared to susceptibility tests using European Committee on Antimicrobial Susceptibility Testing (EUCAST) standard methods and erroneous results were noted. Additionally, we investigated turnaround times for rapid automated antimicrobial susceptibility testing and routine diagnostic testing., Results: We analysed 106 patients with 116 episodes of bacteraemia due to Enterobacterales, with Escherichia coli and Klebsiella pneumoniae being the most frequent isolates. Almost 8% of pathogens were multidrug resistant. Rapid automated antimicrobial susceptibility testing showed category agreement in 98.4% of all interpretable cases. A significant reduction of more than 20 h in turnaround times could be achieved with rapid automated antimicrobial susceptibility testing compared to the routine diagnostic workflow. In the majority of cases, rapid automated antimicrobial susceptibility testing had no effect, given that the empirical therapy was already correct or circumstances did not allow for de-escalation. In 38.8% of cases, antimicrobial therapy was adjusted, whereas eight cases were de-escalated based on rapid automated antimicrobial susceptibility testing alone., Conclusions: Rapid automated antimicrobial susceptibility testing may be a valuable and safe way to accelerate diagnosis. In particular, time to suitable therapy can be shortened in cases of incorrect therapy. However, physicians are reluctant to de-escalate antibiotic therapy based on rapid automated antimicrobial susceptibility testing alone, limiting its impact in everyday clinics. To further explore the potential of rapid automated antimicrobial susceptibility testing, a stringent/compulsory antibiotic stewardship programme would be a valuable next step.

Treatment failure in biofilm-associated bacterial infections is an important healthcare issue. In vitro studies and mouse models suggest that bacteria enter a slow-growing/non-growing state that results in transient tolerance to antibiotics in the absence of a specific resistance mechanism. However, little clinical confirmation of antibiotic tolerant bacteria in patients exists. In this study we investigate a Staphylococcus epidermidis pacemaker-associated endocarditis, in a patient who developed a break-through bacteremia despite taking antibiotics to which the S. epidermidis isolate is fully susceptible in vitro. Characterization of the clinical S. epidermidis isolates reveals in-host evolution over the 16-week infection period, resulting in increased antibiotic tolerance of the entire population due to a prolonged lag time until growth resumption and a reduced growth rate. Furthermore, we observe adaptation towards an increased biofilm formation capacity and genetic diversification of the S. epidermidis isolates within the patient.

Background: To assess the effect of concomitant subgingival rinsing with 10% PVP-iodine during subgingival instrumentation on the prevalence and magnitude of bacteraemia of oral origin., Materials and Methods: Subgingival instrumentation was performed with water or PVP-iodine rinse in patients with periodontitis. Prior to instrumentation, subjects gargled for 1 min with the allocated liquid. Pockets were then rinsed for 1 min and subgingivally instrumented with liquid-cooled (water/PVP-iodine) ultrasonic scalers (1 min). Two minutes later, a blood sample from the arm vein was drawn using a lysis centrifugation blood culture system for quantitative microbiological analysis. Non-parametric statistical tests were performed to assess differences in the prevalence and extent of bacteraemia between groups., Results: Of the 19 samples in each group, oral-borne bacteraemia was detected in 10 of the control and 2 of the test samples. With an average of 3.0 [1; 5] colony forming units, significantly less bacteria and bacteraemia were found in the test group compared to the controls (12.2 [1; 46]) (p = 0.003). Anaerobic bacteria were not found in the test group., Conclusions: Bacteraemia after subgingival instrumentation with concomitant PVP-iodine rinsing is reduced but not eliminated. Therefore, it might be recommended for patients at a high risk of endocarditis or infection of endoprostheses. However, preventive antibiotic treatment should not be omitted., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: The use of probiotics as prophylaxis for necrotizing enterocolitis (NEC) in preterm infants is being increasingly practised., Objective: We report, for the first time, a case series of 3 preterm, very-low-birth-weight (VLBW) infants who developed bacteremia with Bifidobacterium longum on probiotic therapy with Infloran® containing viable B. longum., Methods: We retrospectively reviewed data of 3 infants (of gestational age <30 weeks and birth weight <1,230 g). They were admitted to the neonatal intensive care unit. Clinical data were retrieved from their medical records., Results: In infants 1 and 2, B. longum was isolated from the blood cultures when they were on probiotic therapy with Infloran or shortly after, respectively, and was interpreted as transient bacteremia. The clinical presentation of these infants did not require antibiotic treatment after the isolation of B. longum. Infant 3 developed an NEC despite probiotic therapy with Infloran and the blood cultures showed B. longum growth. This infant required explorative laparotomy and antibiotic treatment. The clinical isolates of B. longum and the strain of the Infloran capsule showed an identical profile on biochemical, mass-spectrometric and molecular analyses, suggesting a direct correlation between the administration of probiotics and bacteremia with B. longum in all 3 infants., Conclusions: The occurrence of bacteremia with bifidobacteria after its prophylactic administration in VLBW infants and its possible clinical consequences are a matter of concern. In the interests of safety, the use of probiotics in such a population should be indicated with caution and requires further investigation., (© 2014 S. Karger AG, Basel.)

Purpose: The aim of this quality control study was to assess the time to initial diagnostic procedures and the time to the first dose of antibiotics in patients with pneumococcal bacteremia, and to investigate whether the timeliness of these interventions influenced outcome., Methods: We retrospectively studied patient characteristics, chronological sequence of diagnostic and therapeutic steps, and the course of disease of all patients with pneumococcal bacteremia at a Swiss university hospital between 2003 and 2009, and we analyzed associations between these factors and the length of hospital stay (LOS) and mortality., Results: A total of 102 episodes of pneumococcal bacteremia in 98 patients were analyzed, of whom 15.7% died during hospitalization. The median time (interquartile range [IQR]) to the first antibiotic dose was 4.0 (2.0-5.9) h, and the median times (IQR]) to blood cultures, chest radiograph, lumbar puncture, and brain computed tomography (CT) scan or magnetic resonance imaging (MRI) were 1.4 (0.5-3.3), 2.5 (1.2-4.2), 4.2 (2.7-7.2), and 2.3 (0.6-6.2) h, respectively. The time to diagnostic procedures and therapy were not associated with LOS or death. Risk factors for death in the univariable analysis were: Charlson comorbidity index [odds ratio [OR] (95% confidence interval) per unit increase, 1.3 (1.1-1.6)], neutropenia [OR 10.1 (2.0-51.0)], human immunodeficiency virus (HIV) infection [OR 3.9 (1.1-13.8)], chronic respiratory disease [OR 4.4 (1.2-16.0)], chronic liver disease [OR 3.2 (1.0-9.7)], smoking [OR 3.8 (1.1-13.5)], injection drug use [OR 9.7 (1.5-63.7)], and antibiotic therapy within 6 months before admission [OR 4.0 (1.3-12.5)]. The multivariable analysis revealed age >60 years (P = 0.048) and alcoholism (P = 0.009) as risks for prolonged LOS., Conclusions: The outcome of pneumococcal bacteremia may be more influenced by patient characteristics than by minor differences in the timeliness of initial diagnostic and therapeutic measures within the first several hours after hospital admission.

Background: Staphylococcus lugdunensis endocarditis has been associated with an aggressive course. The aim of this study was to determine factors associated with the development of endocarditis in patients with S. lugdunensis bacteremia., Methods: A retrospective analysis of all patients with S. lugdunensis bacteremia in three tertiary care centers in Switzerland was performed. Data regarding medical history, symptoms, and susceptibility of S. lugdunensis isolates were collected. Our results were reviewed in the context of the current literature., Results: A total of 28 patients with S. lugdunensis bacteremia were identified. Of the 13 patients with endocarditis, all were community acquired. Cardiac surgery was performed in 85% of these patients; mortality was 23%, reflecting the aggressive course of this disease. In contrast, in the 15 patients without endocarditis, no complications associated with S. lugdunensis bacteremia were observed. In 73%, a probable source was identified in the form of a venous catheter or other foreign device. Only three of these episodes were community acquired. No difference was observed in susceptibility of the S. lugdunensis isolates to penicillin, which was 77% in endocarditis isolates, and 87% in isolates of bacteremia without endocarditis, respectively., Conclusion: S. lugdunensis bacteremia is associated with endocarditis in up to 50% of patients. Every patient with community-acquired S. lugdunensis bacteremia should be carefully examined for signs of endocarditis. Once S. lugdunensis endocarditis is diagnosed, close monitoring is essential and surgical treatment should be considered early. In the nosocomial setting, endocarditis is far less frequent, and S. lugdunensis bacteremia is usually associated with a catheter or other foreign materials.

Brevibacterium spp. were considered apathogenic until a few reports of infections in immunocompromised patients were published. Herein, we present a case of a catheter-related septicemia with Brevibacterium casei in an immunocompetent patient receiving continuous iloprost infusion for pulmonary arterial hypertension and review the clinical presentation of this mainly emerging opportunistic pathogen.

Brevibacterium sp. was isolated from the blood of an acutely ill 18-year-old female with AIDS. The isolate was identified as Brevibacterium casei by use of carbohydrate assimilation tests. Treatment was successful with intravenously administered ciprofloxacin. To our knowledge, this is the first report of sepsis caused by B. casei in a human immunodeficiency virus-infected patient.

We report a case of a retroperitoneal abscess due to Mycoplasma hominis in a young polytraumatized man who developed septicemia under treatment with rifampin and flucloxacillin. M. hominis was recovered from blood cultures as well as from the abscess near the left iliac spine. After 10 days of therapy with clindamycin the patient improved, and intraoperatively taken swabs were culture negative but still positive by PCR.

Dysgonic fermenter 3 (DF-3)-associated bacteremia occurred in a febrile patient with acute myelocytic leukemia during aplasia. Another DF-3 isolate, identical by ribotyping, was grown 10 weeks later from stool collected in the absence of diarrhea. This is the first case in which DF-3 was isolated from blood and stool specimens from the same patient.

Background: The isolation of Propionibacterium acnes in blood cultures is often considered a contaminant. On rare occasions, P. acnes can cause severe infections, including endocarditis and intravascular prosthesis-associated infections. To evaluate the discrimination between a contaminant and a clinically relevant infection we used an Ouchterlony test system to quantify the antibody response to P. acnes in a patient with a proven P. acnes endocarditis. Case Presentation: We report on a 64-year-old Caucasian man who developed P. acnes endocarditis four years following a composite valve-graft conduit replacement of the aortic root. Bacterial growth in blood cultures was detected after an incubation period of 6 days. However, the antibody titer to P. acnes was 1:8 at the time of diagnosis and declined slowly thereafter over 2½ years. The patient's response to the antibiotic treatment was excellent, and no surgical re-intervention was necessary. Conclusion: The working hypothesis of infective endocarditis can be substantiated by serologic testing, which, if positive, provides one additional minor criterion. Moreover, quantification of the antibody response to P. acnes, though not specific, may assist in the differentiation between contaminants and an infection. This quantification may have implications for the patient management, e.g. indication for and choice of the antibiotic therapy. [ABSTRACT FROM AUTHOR]

The article reports the case of a 54-year-old patient with bacteremia and meningitis after a dog bite, in which the etiologic diagnosis was difficult to establish. Retrospective Gram stain of the gram-negative bacteria colonies that grew in both the CSF culture media and in an aerobic blood-culture flask showed gram-negative rods with fusiform shapes suggestive of a Capnocytophaga sp. The patient's condition improved rapidly after administration of ceftriaxone therapy for 13 days. He was discharged 1 day after treatment ended.