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Background: Pneumococcal disease is still considered a global problem. With the introduction of pneumococcal conjugate vaccines (PCVs) serotype epidemiology changed, but antimicrobial resistance persists constituting a serious problem. The current study aimed to determine the serotype distribution and the antimicrobial susceptibility of recent Streptococcus pneumoniae isolates, following implementation of the 13-valent conjugate vaccine (PCV13)., Materials and Methods: From January 2017 to December 2022 we evaluated 116 nonduplicate S. pneumoniae isolates collected from adult patients (21 - 98 years) cared for in the University Hospital of Heraklion, Crete, Greece. Pneumococcal isolates were serotyped by the Quellung reaction, and antimicrobial susceptibility testing was performed using E-test. Multidrug resistance (MDR) was defined as non-susceptibility to at least one agent in ≥3 classes of antibiotics., Results: Among the 116 isolates, 31% were recognized as invasive pneumococcal strains, while 69% were non-invasive. The isolates tested belonged to 25 different serotypes. The most prevalent serotypes were 11A (10.3%), and 35B (10.3%), followed by 3 (9.5%), 15A (7.8%), 25F (6.9%), 19A (5.3%), 35F (5.3%), and others (44.6%). The coverage rates of PCV13 and the pneumococcal polysaccharide vaccine (PPSV23) were 26.7% and 57.8%, respectively. PCV13 and PPSV23 serotypes decreased between 2017 - 2019 and 2020 - 2022, with a parallel increase in the non-vaccine types. Resistance rates to erythromycin, clindamycin, trimethoprim/sulfamethoxazole, penicillin, levofloxacin, and ceftriaxone, were 40.5%, 21.6%, 13.8%, 12.1%, 3.4%, and 0%, respectively. All isolates were susceptible to vancomycin, linezolid, and daptomycin. MDR was observed among 36 (31%) S. pneumoniae isolates., Conclusion: The increasing levels of resistance in S. pneumoniae in Crete, Greece, highlight the need for continuous surveillance of antimicrobial resistance and development of strategies for its reduction, including antimicrobial stewardship programs, increased pneumococcal vaccination, and development of next generation PCVs with a wider serotype coverage., Competing Interests: No conflict of interest., (Copyright © 2024 by The Korean Society of Infectious Diseases, Korean Society for Antimicrobial Therapy, and The Korean Society for AIDS.)

Skin and soft tissue infections (SSTIs) are associated with significant morbidity and healthcare costs, especially when caused by methicillin-resistant Staphylococcus aureus (MRSA). Vancomycin is a preferred antimicrobial therapy for the management of complicated SSTIs (cSSTIs) caused by MRSA, with linezolid and daptomycin regarded as alternative therapeutic options. Due to the increased rates of antimicrobial resistance in MRSA, several new antibiotics with activity against MRSA have been recently introduced in clinical practice, including ceftobiprole, dalbavancin, and tedizolid. We evaluated the in vitro activities of the aforementioned antibiotics against 124 clinical isolates of MRSA obtained from consecutive patients with SSTIs during the study period (2020-2022). Minimum inhibitory concentrations (MICs) for vancomycin, daptomycin, ceftobiprole, dalbavancin, linezolid and tedizolid were evaluated by the MIC Test Strip using Liofilchem strips. We found that when compared to the in vitro activity of vancomycin (MIC 90 = 2 μg/mL), dalbavancin possessed the lowest MIC 90 (MIC 90 = 0.094 μg/mL), followed by tedizolid (MIC 90 = 0.38 μg/mL), linezolid, ceftobiprole, and daptomycin (MIC 90 = 1 μg/mL). Dalbavancin demonstrated significantly lower MIC 50 and MIC 90 values compared to vancomycin (0.064 vs. 1 and 0.094 vs. 2, respectively). Tedizolid exhibited an almost threefold greater level of in vitro activity than linezolid, and also had superior in vitro activity compared to ceftobiprole, daptomycin and vancomycin. Multidrug-resistant (MDR) phenotypes were detected among 71.8% of the isolates. In conclusion, ceftobiprole, dalbavancin and tedizolid exhibited potent activity against MRSA and are promising antimicrobials in the management of SSTIs caused by MRSA.

Exophiala dermatitidis is a dematiaceous, ubiquitous, dimorphic fungus, which can cause a wide range of invasive diseases in both immunocompromised and immunocompetent hosts. Bloodstream infections due to E. dermatitidis are rarely encountered in clinical practice, especially in pediatric patients. We describe a case of central line-associated bloodstream infection due to E. dermatitidis in a 4.5-year-old boy with Ewing's sarcoma. The fungus was isolated from blood specimens taken from the Hickman line. The isolate was identified by its phenotypic characteristics, by MALDI-TOF and by using molecular methods. The infection was successfully treated with voriconazole and catheter removal. The literature was also reviewed on pediatric infections caused by E. dermatitidis, focusing on clinical manifestations and challenges associated with diagnosis and management., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Vaccination against COVID-19 is among the most effective measures to stop the spread of the disease. However, acceptance of vaccination against COVID-19 among HCWs has not been universal and emergence of new variants with increased transmissibility, reduced neutralization by BNT162b2 vaccine-elicited sera and ability to cause breakthrough infections in vaccinated individuals is concerning. The aim of this study was to compare viral load, clinical presentation at diagnosis and type of exposure among vaccinated (with BNT162b2) and non-vaccinated healthcare workers (HCWs)., Methods: Prospective cohort of HWCs diagnosed with COVID-19 by nasopharyngeal PCR from 4 January to 14 April. Viral loads were expressed by the cycle threshold (Ct) in PCR., Results: During the study period 55 HCWs were found positive for SARS-CoV-2, most of whom (44/55) were identified from March 28 to April 14 during an in-hospital COVID-19 outbreak. Of the 55 HCWs, 21 were fully vaccinated and another three had received one dose. Most cases (54/55) were due to variant B.1.1.7. Vaccinated and unvaccinated HCWs did not differ significantly in regards to age, gender, site of acquisition, presence of symptoms at diagnosis and viral load., Conclusions: This study found a similar viral load in vaccinated and non-vaccinated HCWs infected by SARS-CoV-2 variant B.1.1.7, suggesting potentially reduced efficacy of BNT162b2 in preventing transmission of B.1.1.7.

Background: Although Candida is a commensal of the urogenital tract, intrauterine fungal infections are extremely uncommon in clinical practice., Aims: In the present work we evaluated whether amniotic fluid (AF) possesses direct antifungal activity against clinical isolates of Candidaalbicans and other Candida species., Methods: A total of 23 AF samples from pregnant women with gestational age of 38-41 weeks were obtained under aseptic conditions by the aspiration of the amniotic sac during cesarean section. Different Candida species were inoculated in amniotic fluid and Sabouraud broth, used as control, and were incubated at 37°C for 48h. Quantitative cultures of test samples and controls were performed at 0, 4, 8, 12, 24, and 48h., Results: AF collected from 23 pregnant women had consistent and significant inhibitory activity against all Candida isolates tested. Nonetheless, a complete inhibition of growth by all 23 AF samples tested was observed only against Candida glabrata., Conclusions: It is likely that the antifungal activity of the AF against C. albicans, C. glabrata and Candida parapsilosis observed in vitro also exists in vivo, contributing to protect against intrauterine fungal infections., (Copyright © 2021 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

The human organism coexists with its microbiota in a symbiotic relationship. These polymicrobial communities are involved in many crucial functions, such as immunity, protection against pathogens, and metabolism of dietary compounds, thus maintaining homeostasis. The oral cavity and the colon, although distant anatomic regions, are both highly colonized by distinct microbiotas. However, studies indicate that oral bacteria are able to disseminate into the colon. This is mostly evident in conditions such as periodontitis, where specific bacteria, namely Fusobacterium nucrelatum and Porphyromonas gingivalis project a pathogenic profile. In the colon these bacteria can alter the composition of the residual microbiota, in the context of complex biofilms, resulting in intestinal dysbiosis. This orally-driven disruption promotes aberrant immune and inflammatory responses, eventually leading to colorectal cancer (CRC) tumorigenesis. Understanding the exact mechanisms of these interactions will yield future opportunities regarding prevention and treatment of CRC.

Vulvovaginal candidiasis (VVC) is a common infection of the genital tract affecting millions of women worldwide. Data on epidemiological trends of VVC in Greece are scarce. This study was undertaken to evaluate the prevalence of VVC among symptomatic women in Crete, Greece, identify the Candida species involved and determine their susceptibility to antifungals. Over a 6-year period (2012-2017), 10 256 symptomatic women with vaginitis were evaluated. Isolation of yeasts was performed on Sabouraud dextrose agar with chloramphenicol, and the isolates were identified using the API 20 C AUX and/or the Vitek 2 YST card. Susceptibility of the isolates to amphotericin, fluconazole, voriconazole and flucytosine was determined by the Vitek 2 automated system. The results were interpreted according to Clinical and Laboratory Standards criteria. Vaginal swab cultures of 1217 (11.9%) women yielded Candida species. Recurrent VVC was documented in 62 (5.1%) of them. Candida albicans was the most frequently isolated species (75.6%), followed by Candida glabrata (13.6%). Overall, resistance rates to amphotericin B, fluconazole, voriconazole and flucytosine were 0.2%, 6.6%, 1.4% and 2.1%, respectively. Fluconazole resistance of C. albicans significantly increased in the second period of the study (2015-2017) (P = 0.031). This study demonstrated that VVC is a common infection among women in our region, with C. albicans being the predominant species involved. Although resistance to antifungals was infrequent, resistance to fluconazole among C. albicans isolates was found to significantly increase with time. Continued surveillance of changes in species distribution and susceptibility to antifungals are necessary to guide treatment., (© 2019 Blackwell Verlag GmbH.)

Background: Pneumococcal disease is a major cause of morbidity and mortality worldwide, especially in patients with comorbidities and advanced age. This study evaluated trends in epidemiology of adult pneumococcal disease in Crete, Greece, by identifying serotype distribution and antimicrobial resistance of consecutive Streptococcus pneumoniae strains isolated from adults during an 8-year time period (2009-2016) and the indirect effect of the infant pneumococcal higher-valent conjugate vaccines 10-valent pneumococcal conjugate vaccine (PCV10) and 13-valent pneumococcal conjugate vaccine (PCV13)., Materials and Methods: Antimicrobial susceptibility was performed by E-test and serotyping by Quellung reaction. Multidrug resistance (MDR) was defined as non-susceptibility to penicillin (PNSP) combined with resistance to ≥2 non-β-lactam antimicrobials., Results: A total of 135 S. pneumoniae strains were isolated from adults during the study period. Twenty-one serotypes were identified with 17F, 15A, 3, 19A, and 11A, being the most common. The coverage rates of PCV10, and PCV13 were 17.8% and 37.8%, respectively. PCV13 serotypes decreased significantly from 68.4% in 2009 to 8.3% in 2016 ( P = 0.002). The most important emerging non-PCV13 serotypes were 17F, 15A, and 11A, with 15A being strongly associated with antimicrobial resistance and MDR. Among all study isolates, penicillin-resistant and MDR strains represented 7.4% and 14.1%, respectively. Predominant PNSP serotypes were 19A (21.7%), 11A (17.4%), and 15A (17.4%). Erythromycin, clindamycin, tetracycline, trimethoprim-sulfamethoxazole, and levofloxacin resistant rates were 30.4%, 15.6%, 16.3%, 16.3%, and 1.5%, respectively., Conclusion: Although pneumococcal disease continues to be a health burden in adults in Crete, our study reveals a herd protection effect of the infant pneumococcal higher-valent conjugate vaccination. Surveillance of changes in serotype distribution and antimicrobial resistance among pneumococcal isolates are necessary to guide optimal prevention and treatment strategies., Competing Interests: No conflicts of interest., (Copyright © 2018 by The Korean Society of Infectious Diseases and Korean Society for Chemotherapy.)

Objective: Recent studies have shown that in carefully selected patients, conservative treatment alone can be an option in the management of spinal epidural abscess (SEA). The aim of this study was to identify prognostic factors of outcome in patients with spontaneous SEA treated conservatively., Patients and Methods: A retrospective cohort study of all patients with spontaneous SEA treated with antibiotics alone from January 2012 to December 2015 was conducted in a 1200-bed tertiary referral center. Demographic, clinical, microbiological, and radiological characteristics were analyzed. Failure of medical treatment was defined as the need for delayed surgical intervention, no neurological improvement or deterioration, death due to the infection, or relapse after hospital discharge., Results: We identified 21 patients diagnosed with spontaneous SEA treated conservatively. Median age was 72 years and 10 patients were male. Eleven patients presented with radicular weakness and/or radicular sensory deficit, or incomplete cord injury. Inflammatory markers were markedly elevated in all patients. Thirteen patients were successfully treated with conservative treatment, while among 8 patients with treatment failure, 1 died due to the infection. Presence of serious neurological deficits and infection due to methicillin-resistant S. aureus (MRSA) were associated with failure of conservative treatment. Notably, neither the extension nor the location of the abscess on magnetic resonance imaging (MRI) was associated with failed medical management., Conclusions: A significant proportion of patients with spontaneous SEA can respond to antibiotic treatment alone. However, in patients with infection due to MRSA or with severe neurological impairment, conservative management has an increased risk of failure., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Colonization of the gastrointestinal (GI) tract by Candida species is a principal pathogenetic event for development of invasive candidiasis. Importantly, the effect of echinocandins, the preferred antifungal agents for treatment of invasive candidiasis, on GI tract colonization by Candida spp. is currently unknown. Herein, we used an established model of persistent murine GI tract colonization by Candida albicans to test the ability of different echinocandins to eradicate the yeast from murine gut. Adult male Crl:CD1 (ICR) BR mice were fed with chow containing C. albicans and subsequently treated with different echinocandins or normal saline via daily intraperitoneal injections for 10 days. Quantitative stool cultures were performed immediately before (week one), and weekly for three months after discontinuation of treatment. Notably, treatment with all three echinocandins used (caspofungin, anidulafungin, and micafungin) resulted in eradication of Candida albicans from the stools, as evidenced by the significant reduction of yeast cells from a mean of 4.2 log10 CFU/g of stool before treatment (week one of colonization) to undetectable (<2 log10 CFU/g of stool) levels (week 12, P < 0.0001). In contrast, there was no significant reduction of Candida yeast cells in the stools of control mice. Collectively, the ability of echinocandins to eradicate C. albicans from the stools could have important implications in prophylaxis of high-risk patients for development of invasive candidiasis originating from the GI tract., (© The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)