New Microbiologica最新文献

Corynebacterium pseudodiphtheriticum, a Gram-positive rod belonging the oropharynx microbiota, is usually described in pulmonary infections, especially in immunocompromised patients. This paper describes a rare case of native aortic infectious endocarditis (IE) and reviews the literature on similar cases. A 62-year-old man with rheumatic fever since childhood was hospitalized for surgical treatment of a febrile IE due to C. diphtheriticum with a large vegetation (15.8 X 8.3 mm). MALDI-TOF-MS from strain isolated in positive blood cultures identified C. pseudodiphtheriticum (2.34), and 16S rRNA sequencing from the valve sample confirmed the identification. The summary of 25 cases shows that the outcome of an IE due to C. pseudodiphtheriticum is bad. The review of the literature shows that this agent found in blood cultures in a cardiovascular context deserves to be explored meticulously because an unfavorable prognosis is frequent.

BK virus (BKV) associated with hemorrhagic cystitis (HC) is the most important complication that develops after hematopoietic stem cell transplantation (HSCT) in patients with hematological malignancies. This study aims to investigate BKV infections and HC in pediatric patients after allogeneic hematopoietic stem cell transplantation. Between November 2018 and November 2019, a total of 51 patients between the ages of 11 months and 17 years were included in the study. BKV Bosphore ® v1 quantification kit (Geneworks Anatolia, Turkey) was used for the detection of BKV DNA in urine and blood samples. Among the total of 51 patients, the incidence of BKV infection was found to be 86.3%. Allogeneic HSCT was performed in 40 patients and autologous HSCT in 11 patients. BK viruria and/or viremia were detected in 85% (44) of patients who underwent allogeneic HSCT and in 90% in the autologous group. High-level BK viruria (>107 copies/mL) was found in 41% (9) of 22 patients who were BKV positive before transplantation, while in 27.5% (8) of 29 patients who were BKV negative before transplantation; thus, BKV positivity before transplantation was considered a risk factor for high-level BK viruria. Acute GVHD developed in 6 of 40 patients in the allogeneic group. HC was prevented in 12 (67%) of 18 patients who received preemptive treatment, while HC developed in 6 (33%). HC occurred at a median of 35 days (17-49 days) post-transplant. Despite preemptive treatment, 6 (15%) patients who developed HC associated with BKV were in the allogeneic group but not in the autologous group. Of these patients with HC, 5 received a myeloablative treatment regimen, and 1 patient was given a reduced-intensity treatment regimen. The viral load in urine was found to be 107-9 copies/mL within 2 weeks before the development of HC and has been identified as a prognostic indicator. In conclusion, early diagnosis of viral infections by monitoring BKV viral load in HSCT patients will be effective in preventing the progression of complications such as BKV-associated HC by providing timely initiation of preemptive treatment.

Ultraviolet-C (UVC) has been used to cause virus inactivation. The virucidal activity of three UV light lamps [UVC high frequencies (HF), UVC+B LED and UVC+A LED] was evaluated against the enveloped feline coronavirus (FCoVII), a surrogate model of SARS-CoV-2, the enveloped vesicular stomatitis virus (VSV), and the naked encephalomyocarditis virus (EMCV). Virucidal assays were performed at different time points of UV-light exposure (i.e., 5, 30 minutes and 1, 6, and 8 hours), placing each virus 180 cm below the perpendicular irradiation of the lamp and 1 and 2 meters from the perpendicular axis. We found that the UVC HF lamp had virucidal effects (≥96.8% of virus inactivation) against FCoVII, VSV and EMCV after 5 minutes of irradiation at each distance analyzed. Moreover, the UVC+B LED lamp had the highest inhibitory effects on FCoVII and VSV infectivity (≥99% of virus inactivation) when these viruses were settled below the perpendicular axis of the lamp for 5 minutes. Conversely, the UVC+A LED lamp was the least effective, achieving ≥85.9% inactivation of enveloped RNA viruses after 8 hours of UV exposure. Overall, UV light lamps, and in particular UVC HF and UVC+B LED ones, had a rapid and strong virucidal activity against distinct RNA viruses, including coronaviruses.

In this study we evaluated the antiviral activity of the Silver Barrier® disinfectant against SARSCoV-2. Silver Barrier® showed time- and concentration-dependent antiviral activity against SARSCoV-2. After 5 min contact time, Silver Barrier® at 0.002% showed a strong inhibitory effect (p<0.001), with a 2-fold reduction of viral genome copy numbers, and a robust suppression (94%) of SARS-CoV-2 infectivity. Considering the effects obtained in solution and within a very short time, Silver Barrier® stands as an excellent new candidate for the disinfection of work environments, especially at the healthcare level, where there are people at high risk of serious illnesses.

In the present study, the effects of progesterone (PRO) and estradiol (EST) on the growth, adhesion, invasion, biofilm and antibiotic susceptibilities of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) were examined. We also investigated effects of S. aureus infections on the viability of human breast adenocarcinoma (MCF-7) cells in the presence/ absence of hormones. The effects of hormones on the growth, adhesion and invasion of S. aureus were investigated in MCF-7 cells. Growths were assessed spectrophotometrically. Adhesive/invasive bacterial counts were examined by colony counting method. Biofilm was determined using microtiter plate assay. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of ciprofloxacin (CIP) and gentamicin (GN) were examined by the microdilution method. Cell viabilities were detected via methylthiazolyldiphenyl-tetrazolium bromide assay. Growths of bacteria were decreased by hormones (p<0.0001). Adhesion was affected differently depending on hormones and strains tested. Hormones reduced the invasion (p≤0.0001) and biofilm (p<0.0001) of both strains. Progesterone increased and estradiol decreased MIC and MBC of CIP for MRSA; however, MICs of MSSA were not affected. S. aureus infected-MCF-7 viabilities were decreased in the presence of hormones except for high-level PRO (p<0.05). Our results showed that these two hormones have different effects on behaviors of S. aureus strains.

Transcriptome analysis for the original Bacillus subtilis K1 strain and UV mutagenic strain UW07 with high yield of pectate lyase was implemented with RNA-seq. The function of genes was annotated and metabolic pathways were classified to look for different expression genes and classify these genes into related metabolic pathways to reveal the high-yield mechanism of pectate lyase in UW07. The results showed that 397 genes were up-regulated and 617 genes were down-regulated compared with the original strain. The up-regulated genes were mainly involved in ABC transporters, two-component system, biosynthesis of amino acids, and carbon metabolism.

Bloodstream infections (BSIs) monitoring and antibiotic susceptibility assumes a priority relevance to guide antibiotic treatment strategies and prevention programs. The study aims to identify the most common causative agents of BSIs, seasonal distribution and variation of antimicrobial susceptibility rates during a 6-year period in a in a Level II EAD Southern Italian Hospital. The study was conducted from 2016 to 2021 at Hospital of National Relevance (AORN) Sant'Anna and San Sebastiano, Caserta, Campania Region in Italy. BSIs Gram positive causative pathogens were S. aureus and Enterococci; Gram negative pathogens were E. coli, K. pneumoniae, P. aeruginosa and A. baumannii. Seasonal distribution showed the main incidence in April-June for Gram positive BSIs pathogens and in July-September months for Gram negative. Antimicrobial susceptibility fluctuations rates from 2016-2018 to 2019-2021 highlighted a significant decrease in S. aureus oxacillin resistance rates. Enterococci incremented resistance was reported for gentamicin. Gram negative pathogens antimicrobial susceptibility revealed decreased carbapenem-resistance rates for K. pneumoniae (-21.5%) and P. aeruginosa (-19.7%). A. baumannii colistin resistance had a significant increase in 2019-2021. K. pneumoniae and E. coli isolates showed decreased trend of extended-spectrum -lactamase-producing (ESBL) and carbapenem-resistant (CRE) resistance profiles. Our finding reflects the success of our Istitution regarding antimicrobial stewardship program and highlights the need to know the trend of antimicrobial resistance characterization focus on local pathogens' profile. In this way, in conjunction with infection control strategies, il could be possible to constantly reduce the spread of Multi Drug Resistant organisms.

Candida-related bloodstream infections (BSIs) represent a severe condition associated with health care in the critical patient, with an increasing incidence of Candida non-albicans species. These infections could lead to several and unusual complications in high-risk patients due to various factors, including a prolonged hospital stay and invasive medical interventions. Here we report a case of a Candida krusei septic thrombophlebitis in an ARDS patient admitted to the ICU, complicated by a late onset prostatic abscess. To our knowledge, our patient represents the first reported case of a prostatic abscess due to Candida krusei treated with pharmacological therapy alone.

Cefditoren is an oral third-generation cephalosporin with a large spectrum activity against Gram-negative and Gram-positive bacteria which are reported to be responsible for respiratory tract and skin and skin structure infections. In this work we reviewed the pharmacodynamics, pharmacokinetics, and the main clinical indications of cefditoren. Similarly to other beta-lactams, cefditoren is a time-dependent antibiotic, and its "best" PK/PD target is probably 40% dosing interval time > 4- 5-fold MIC and 40-70% dosing interval time > 4- 5-fold MIC for bacteriostatic and bactericidal effect, respectively. In fasting patients oral bioavailability is low and increases when the drug is taken with food. This cephalosporin has significant bactericidal activity against S. pneumoniae (both penicillin-susceptible and penicillin-resistant strains), S. pyogenes, H. Influenzae and M. catarrhalis, as well as methicillin-susceptible S. aureus (MSSA). Regarding Enterobacterales, cefditoren has very low MICs90 against K. pneumoniae andE. coli but is not active against AmpC-, ESBL- and carbapenemase-producer' strains. Licensed indications are treatment of exacerbations of chronic bronchitis,acute rhinosinusitis, otitis media, upper respiratory tract infections (pharyngitis/tonsillitis), lower community-acquired respiratory tract infections (LRTIs), and skin and skin-structure infections (SSTI). Cefditoren might have a role in switching from parenteral to oral therapy in acute pyelonephritis and LRTIs. with a reduction of adverse effects and hospital costs. Eventually, due to its supposed binding to enterococcal penicillin binding proteins (PBPs) cefditoren, in combination with other beta-lactams, might have a role in partial oral enterococcal endocarditis treatment..

Severe inflammation and one or more extrapulmonary organ dysfunctions have been observed in those who had recently developed COVID-19, except for a macrophage activation syndrome-like picture. A 50-year-old female patient was admitted to the emergency department with fever and a history of COVID-19 infection. More than one area of hemophagocytosis was found in the bone marrow aspiration. The HLH-2004 protocol was started with neurological involvement and she underwent splenectomy due to massive intra-abdominal bleeding secondary to splenic laceration on the 3rd day. Multiple microthrombosis and infarcts were observed in the splenectomy specimen. At the 4th week of the treatment, she was discharged with oral agents. Splenic microthrombosis and splenic rupture due to "multisystem inflammatory syndrome in adults" are the most important findings of this report.