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Staphylococcus epidermidis is an opportunistic pathogen and a frequent cause of nosocomial infections. In this work, we show that, among 51 S. epidermidis isolates from an Italian hospital, only a minority displayed biofilm formation, regardless of their isolation source (peripheral blood, catheter, or skin wounds); however, among the biofilm-producing isolates, those from catheters were the most efficient in biofilm formation. Interestingly, most isolates including strong biofilm producers displayed production levels of PIA (polysaccharide intercellular adhesin), the main S. epidermidis extracellular polysaccharide, similar to reference S. epidermidis strains classified as non-biofilm formers, and much lower than those classified as intermediate or high biofilm formers, possibly suggesting that high levels of PIA production do not confer a particular advantage for clinical isolates. Finally, while for the reference S. epidermidis strains the biofilm production clearly correlated with the decreased sensitivity to antibiotics, in particular, protein synthesis inhibitors, in our clinical isolates, such positive correlation was limited to tetracycline. In contrast, we observed an inverse correlation between biofilm formation and the minimal inhibitory concentrations for levofloxacin and teicoplanin. In addition, in growth conditions favoring PIA production, the biofilm-forming isolates showed increased sensitivity to daptomycin, clindamycin, and erythromycin, with increased tolerance to the trimethoprim/sulfamethoxazole association. The lack of direct correlation between the biofilm production and increased tolerance to antibiotics in S. epidermidis isolates from a clinical setting would suggest, at least for some antimicrobials, the possible existence of a trade-off between the production of biofilm determinants and antibiotic resistance.

Antimicrobial resistance is a worldwide problem, and resistance in Enterobacteriaceae, particularly Escherichia coli and Klebsiella pneumoniae, is a critical threat to human health. Inappropriate and unnecessary use of antibiotics in human health care is the most common cause for the development and spread of antimicrobial resistance. In this work, we retrospectively analyzed the antimicrobial data of E. coli strains isolated from midstream urinary samples over a 20-year period (2000-2019). The aim was to provide useful information to clinicians to prescribe a more appropriate empirical antibiotic therapy. A total of 30,955 unique E. coli isolates from positive midstream urine samples of inpatients (1,198) and outpatients (29,757) were collected. Except for carbapenems, over time all the antibiotics tested showed increasing resistance rates in both groups (p < 0.0001). On the other hand, fosfomycin and nitrofurantoin presented significant decreasing trends in resistance rate (p < 0.05). There were significant increases in extended-spectrum β-lactamases- and multidrug resistance positive isolates starting in 2000 (p < 0.0001), with similar results in both groups. Ciprofloxacin, gentamicin, trimethoprim/sulfamethoxazole, and third-generation cephalosporin resistances significantly increased with increasing age (p < 0.0001). Collectively, E. coli resistance rates severely increased during the study period, except for fosfomycin and nitrofurantoin. The need of monitoring studies about antibiotic nonsusceptibilities at local and regional levels are necessary to enhance the focus on antimicrobial stewardship, to reduce antimicrobial consumption and to detect alarming resistance mechanisms.

Introduction: A lack of updated data on the burden and profile of anaerobic bloodstream infections (ABIs) exists. We assessed the incidence of ABIs and trends in antimicrobial resistance in anaerobes isolated from blood in Italy. Material and methods: We conducted a retrospective study on 17 Italian hospitals (2016-2020). Anaerobes isolated from blood culture and their in vitro susceptibility profiles (EUCAST-interpreted) were registered and analyzed. Results: A total of 1960 ABIs were identified. The mean age of ABIs patients was 68.6 ± 18.5 years, 57.6% were males. The overall incidence rate of ABIs was 1.01 per 10.000 patient-days. Forty-seven% of ABIs occurred in medical wards, 17% in ICUs, 14% in surgical wards, 7% in hemato-oncology, 14% in outpatients. The three most common anti-anaerobic tested drugs were metronidazole (92%), clindamycin (89%) and amoxicillin/clavulanate (83%). The three most common isolated anaerobes were Bacteroides fragilis (n = 529), Cutibacterium acnes (n = 262) and Clostridium perfringens (n = 134). The lowest resistance rate (1.5%) was to carbapenems, whereas the highest rate (51%) was to penicillin. Clindamycin resistance was >20% for Bacteroides spp., Prevotella spp. and Clostridium spp. Metronidazole resistance was 9.2% after excluding C. acnes and Actinomyces spp. Bacteroides spp. showed an increased prevalence of clindamycin resistance through the study period: 19% in 2016, 33% in 2020 (p ≤ 0.001). Conclusions: Our data provide a comprehensive overview of the epidemiology of ABIs in Italy, filling a gap that has existed since 1995. Caution is needed when clindamycin is used as empirical anti-anaerobic drug.

Antimicrobial resistance is a worldwide problem, and resistance in Enterobacteriaceae, particularly

The β-lactams have a central place in the antibacterial armamentarium, but the increasing resistance to these drugs, especially among Gram-negative bacteria, is becoming one of the major threats to public health worldwide. Treatment options are limited, and only a small number of novel antibiotics are in development. However, one of the responses to this threat is the combination of β-lactam antibiotics with β-lactamase inhibitors, which are successfully used in the clinic for overcoming resistance by inhibiting β-lactamases. The existing inhibitors inactivate most of class A and C serine β-lactamases, but several of class D and B (metallo-β-lactamase) are resistant. The present review provides the status and knowledge concerning current β-lactamase inhibitors and an update on research efforts to identify and develop new and more efficient β-lactamase inhibitors.

Background Nowadays, transvenous lead extraction (TLE) is considered an essential technique in lead management strategy. Since 2011, a multidisciplinary approach was undertaken in our centre involving electrophysiologists, cardiac surgeons and anaesthesiologists to improve cross- unit cooperation and minimize complications and mortality. The present paper reports procedural outcomes and complications of our lead extraction experience. Methods We retrospectively collected and analysed data from all consecutive patients undergoing cardiac implantable electronic device leads TLE at the IRCCS Centro Cardiologico Monzino between January 2011 and November 2017. Results One-hundred fifty patients (111 males, 68 ± 13 years) underwent extraction procedures. The most common extraction indication were infections (86.7%) and TLE was carried out by laser-based approach in 88 (58.6%) patients, by mechanical dilating sheaths in 58 (38.7%) patients and by a combined approach (TLE + open surgical intervention) in 4 (2.7%) patients. Procedural success was obtained in 146 (97.3%) cases with only 3 (2.0%) major complications with 2 cases of structural injury with tamponade requiring emergent median sternotomy. Open surgery extraction was required in 4 patients, after an attempt to TLE, due to leads strict adhesion to cardiac or vascular structures, whereas in 5 (3.3%) cases, the treatment of choice was a combined approach consisting in transvenous leads extraction followed by planned surgery. Conclusions TLE is a complex procedure that sometimes leads to fatal complications. In our single center experience, a multidisciplinary approach involving electrophysiologist, cardiac surgeon, anaesthesiologist in an operating room allows a safer approach and major complications treatment.

Background: Vulvovaginal candidiasis (VVC) is the second most common infection of the genital tract affecting millions of women worldwide. Data concerning the distribution and antifungal resistance of Candida species responsible of VVC vary among countries and population studied. Objectives: The aim of this work was to determine the prevalence, species distribution and antifungal susceptibility patterns of Candida species among symptomatic women over a 20-year period. Methods: A total of 5,820 unique samples were retrospectively identified. Out of them, 1,046 (18%) were diagnosed with VVC. Results: Women between 18 and 30 years had the highest prevalence rate of VVC (21%). Women aged less than 18 years and greater than 51 years had the highest prevalence rates of vaginal bacterial infections. Thirty-five (3.3%) women presented recurrent VVC. The most common yeast isolated was C. albicans, followed by C. glabrata, C. krusei, and C. parapsilosis. Non-Candida albicans species (NAC) were more significantly isolated among women aged 51 or above, than in women included in other groups (p < 0.01). Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. NAC species presented higher resistance rates against fluconazole (30%) and voriconazole (25%). C. krusei and C. glabrata isolates showed lower MICs than most of the strains against amphotericin B (1 mg/L) and flucytosine (1 mg/L). Conclusions: Our findings indicated that continued surveillance on Candida species distribution and non-susceptibility rates to antifungals should be routinely reported to help the selection of the most appropriate drug, to avoid the emergence of resistant strains, and to improve the patient's outcomes.

Background and aims: Rapid and accurate diagnosis is essential to limit the spread of SARS-CoV-2 and for patient’s management. Currently, real-time reverse transcription polymerase chain reaction (RT-PCR) is the recommended laboratory test to detect SARS-CoV-2. However, the requirement of special instruments and skilled personnel have limited the use of this technique. Recently, several rapid antigen detection tests have been developed and used as frontline. The aim of this work was to assess the performances of STANDARD F COVID-19 Ag FIA Kit, a rapid fluorescence immunoassay for the detection of SARS-CoV-2 nucleoprotein antigens, in comparison to RT-PCR.Materials and methods: Twenty-three nasopharyngeal swabs were collected and tested. Results: Among the 20 positive RT-PCR samples, 9 were detected by the immunofluorescence assay, reporting an overall sensitivity of 45%. The sensitivity increased to 64% in the case of a high viral load, where all three target genes, RdRp, N, and E, were detected by RT-PCR. Conclusions: A better antigen detection rate is associated with low Cycle threshold values which are inversely related to the viral load. STANDARD F COVID-19 Ag test cannot be considered as the frontline assay for COVID-19 diagnosis, but it might be used in association with clinical signs of patients to reduce the number of RT-PCR testing.

This record contains raw data (powerpoint with embedded quantitative data) related to the article "Digital PCR for high sensitivity viral detection in false-negative SARS-CoV-2 patients". Abstract Patients requiring diagnostic testing for coronavirus disease 2019 (COVID-19) are routinely assessed by reverse-transcription quantitative polymerase chain reaction (RT-qPCR) amplification of Sars-CoV-2 virus RNA extracted from oro/nasopharyngeal swabs. Despite the good specificity of the assays certified for SARS-CoV-2 molecular detection, and a theoretical sensitivity of few viral gene copies per reaction, a relatively high rate of false negatives continues to be reported. This is an important challenge in the management of patients on hospital admission and for correct monitoring of the infectivity after the acute phase. In the present report, we show that the use of digital PCR, a high sensitivity method to detect low amplicon numbers, allowed us to correctly detecting infection in swab material in a significant number of false negatives. We show that the implementation of digital PCR methods in the diagnostic assessment of COVID-19 could resolve, at least in part, this timely issue., Te present research was in part funded from Institutional resources (Ricerca 5 per mille, Italian Ministery of Health) and in part from a grant issued to MP by Regione Lombardia (POR FESR 2014���2020-LINEA 2A COVID-grant no. 1850333).

The spread of resistance to vancomycin and other last-resort drugs in Enterococcus spp. remains of concern. In Italy, surveillance data for enterococcal bloodstream isolates in humans are scant. The aim of our study was to assess the incidence trends of bacteremias due to Enterococcus species and their prevalence trends of antimicrobial resistance. We retrospectively included all consecutive not-duplicate Enterococcus species isolated from blood cultures, in patients from 11 Italian hospitals (2011-2017). Incidence was defined as the number of isolates per 10,000 patient-days, while resistance prevalence was defined as the number of resistant strains divided by the number of tested strains. We included 4,858 isolates (59%, 36%, and 5% due to Enterococcus faecalis, E. faecium, and other Enterococcus spp., respectively). Over the study period, the incidence of bacteremias due to E. faecalis (incidence rate ratio [IRR]: 1.02, 95% confidence interval [CI]: 1.00-1.04, p = 0.008) and E. faecium increased (IRR: 1.03, 95% CI: 1.01-1.05, p

The human body is inhabited by around 1013 microbes composing a multicomplex system, termed microbiota, which is strongly involved in the regulation and maintenance of homeostasis. Perturbations in microbiota composition can lead to dysbiosis, which has been associated with several human pathologies. The gold-standard method to explore microbial composition is next-generation sequencing, which involves the analysis of 16S rRNA, an indicator of the presence of specific microorganisms and the principal tool used in bacterial taxonomic classification. Indeed, the development of 16S RNA sequencing allows us to explore microbial composition in several environments and human body districts and fluids, since it has been detected in “germ-free” environments such as blood, plasma, and urine of diseased and healthy subjects. Recently, prokaryotes showed to generate extracellular vesicles, which are known to be responsible for shuttling different intracellular components such as proteins and nucleic acids (including 16S molecules) by protecting their cargo from degradation. These vesicles can be found in several human biofluids and can be exploited as tools for bacterial detection and identification. In this review, we examine the complex link between circulating 16S RNA molecules and bacteria-derived vesicles.