Background/Objectives: Various factors associated with seasonality, including temperature, humidity, geographical composition, and seasonal fluctuations, can influence the trends of microbes responsible for hospital infections, such as Candida spp. This study evaluates the seasonal variability of Candida spp. bloodstream infections and antifungal resistance in hospitalized patients in Sicily. Methods: We retrospectively analyzed the demographic and epidemiological characteristics of 175 patients with blood cultures positive for Candida spp. Who were hospitalized at University Hospital Paolo Giaccone (A.U.O.P.), University of Palermo, Italy, from 1 January 2022 to 31 December 2024. Data on Candida species and antifungal resistance were also collected from the hospital’s database system to prevent and control hospital infections in A.U.O.P. Results: A total of 175 patients, 57.7% males, with a mean age of 68.3 years, were included in this study. Candida parapsilosis, Candida albicans, and Candida glabrata were more frequent in ICU (54.5%, p = 0.0001), medical (72.5%, p = 0.0003), and surgical settings (24%, p = 0.0161), respectively. C. parapsilosis was more frequent in dead patients (53.2%, p = 0.005). Among the seasons, we observed a significantly higher presence of C. glabrata in Autumn (20%, p = 0.0436). From the analysis of the seasons, C. parapsilosis and C. albicans were more frequent for each season, except in Spring, where the most frequent isolates were C. glabrata (5.1%, p = 0.0237) and C. parapsilosis (9.7%, p < 0.0001). The antifungal with the most resistance to Candida spp. was fluconazole in all seasons. Conclusions: Our study highlights the seasonal trends in Candida spp. and antifungal resistance, emphasizing climate change’s challenges on fungal diseases. These findings may contribute to improving prevention and treatment strategies for candidemia.

Enterococcus hirae is a rare pathogen in human infections, although its incidence may be underestimated due to its difficult isolation. We describe the first known case of E. hirae infective endocarditis (IE), which involves the mitral valve alone, and the seventh E. hirae IE worldwide. Case presentation: a 62-year-old male was admitted to our department with a five-month history of intermittent fever without responding to antibiotic treatment. His medical history included mitral valve prolapse, recent pleurisy, and lumbar epidural steroid injections due to lumbar degenerative disc disease. Pre-admission transesophageal echocardiography (TEE) showed mitral valve vegetation, and Enterococcus faecium was isolated on blood cultures by MALDI-TOF VITEK MS. During hospitalization, intravenous (IV) therapy with ampicillin and ceftriaxone was initiated, and E. hirae was identified by MALDI-TOF Bruker Biotyper on three blood culture sets. A second TEE revealed mitral valve regurgitation, which worsened due to infection progression. The patient underwent mitral valve replacement with a bioprosthetic valve and had an uncomplicated postoperative course; he was discharged after six weeks of IV ampicillin and ceftriaxone treatment.

Background: Clostridioides difficile infection (CDI) remains a challenging condition, particularly in severe or recurrent cases. This study aimed to identify factors associated with recurrent CDI (rCDI), severe disease (defined by ZAR score or ESCMID criteria), death during CDI, and bloodstream infections (BSI) or candidemia within 8 weeks of CDI onset. Methods: We conducted a prospective study at an Italian university hospital that included all adult CDI cases diagnosed between November 2022 and December 2024. Statistical analyses were performed with IBM SPSS Statistics. A p-value < 0.05 was considered statistically significant in univariate analyses. For the multivariable analysis, we selected the variables that were statistically significant in the univariate analysis and considered the most clinically relevant. Results: A total of 161 CDI cases were identified. Recurrence occurred in 13%, higher than the 4% reported in a previous retrospective cohort at the same center (2013–2022). In univariate analysis, independent predictors of recurrent CDI (rCDI) were therapeutic regimens including oral vancomycin (p = 0.008; OR 6.17; 95% CI 1.36–27.97), peripheral vascular disease (PVD) (p < 0.001; OR 5.92; 95% CI 2.07–16.94), and dysphagia (p = 0.034; OR 4.61; 95% CI 1.25–17.07), whereas fidaxomicin use was associated with a protective effect (p = 0.016; OR 0.17; 95% CI 0.04–0.78). In multivariable analysis, oral vancomycin use (p = 0.008; OR 15.03) and peripheral vascular disease (p = 0.002; OR 7.27) remained independently associated with rCDI. Overall, 15 of 161 patients (9.3%) died during the CDI episode (either presenting CDI or rCDI), with all deaths directly attributable to CDI. Mortality during CDI was associated with age > 77 years (median value of the study population), transfer from a nursing home or long-term care facility within the previous 3 months, lymphoma, hematological malignancy, peripheral vascular disease, connective tissue disease, immobilization syndrome, dysphagia, elevated lactate levels (>1 mmol/L), septic shock, severe or severe-complicated CDI according to ESCMID criteria, severe-complicated CDI according to ESCMID criteria, leukocytosis (WBC > 15,000/mm³) during CDI, ZAR score ≥ 2, concomitant BSI, and concomitant pneumonia. During follow-up, 11 of 127 (8.7%) patients developed a BSI. BSI was associated with corticosteroid use and osteomyelitis. Only four patients developed candidemia due to Candida albicans during follow-up. Conclusions: Our study confirms that Clostridioides difficile infection remains a major clinical challenge, particularly due to its high recurrence rate and the burden of severe forms. The evidence strongly supports the preferential use of fidaxomicin, which should now be regarded as the standard of reference in clinical practice.

Background: Rapid antimicrobial susceptibility testing (RAST) allows early detection of resistance directly from positive blood cultures, potentially improving outcomes in bloodstream infections (BSIs). We evaluated the performance of EUCAST RAST for Gram-negative ESKAPEEc pathogens and characterized carbapenemase genes in carbapenem-resistant Klebsiella pneumoniae (CRKP). Methods: A total of 354 positive blood cultures were screened, including 51 monomicrobial Gram-negative ESKAPEEc isolates. RAST results at 4, 6, 8, and 16–20 h were compared with standard antimicrobial susceptibility testing (AST) obtained using the BD Phoenix™ system. Categorical agreement (CA) and error frequency were calculated. Multiplex PCR and Sanger sequencing were performed on 15 CRKP isolates to identify carbapenemase genes and allelic variants. Results: 51 Gram-negative ESKAPEEc isolates met the inclusion criteria for RAST (15 E. coli, 19 K. pneumoniae, 11 A. baumannii, and 6 P. aeruginosa). Overall performance varied markedly by species and antibiotic. E. coli showed frequent unreadable or ATU zones at early timepoints and wide CA variability (50–100%), with high very major error (VME) rates for AMP, TZP, and CAZ, particularly at 6–8 h. K. pneumoniae displayed consistently high CA (mostly 100%) for carbapenems, CAZ, and TZP. A. baumannii demonstrated excellent agreement (100% for most agents), except for GEN at 6–8 h. P. aeruginosa could be evaluated only at 16–20 h, showing high CA for AMK, CAZ, and CIP; lower CA for MEM (83%); non-calculable CA for IMI due to universal ATU readings; and a CA value of 0% for TZP due to the predominance of the ATU results. VMEs ranged from 0% to 26.1% across species and reading times, but carbapenems did not generate VMEs. Molecular analysis revealed bla_KPC in 66.7%, bla_NDM in 46.7%, and bla_OXA-48 in 33.3% of isolates, with co-occurrence in several strains. Sequencing identified bla_KPC-2 and bla_NDM-1 as the predominant variants, with one isolate harboring bla_NDM-5. Conclusions: EUCAST RAST markedly accelerates susceptibility reporting from positive blood cultures, but its accuracy is species- and time-dependent. Performance was excellent for K. pneumoniae (including CRKP) and A. baumannii and acceptable for P. aeruginosa at 16–20 h. In contrast, E. coli showed frequent ATU results at early timepoints and high ME/VME rates, making readings before 8 h unreliable for clinical decisions. Overall, RAST can effectively support rapid antimicrobial stewardship when species-specific limitations are recognized, and early-timepoint results are interpreted with caution.

Human subcutaneous dirofilariasis caused by Dirofilaria repens is an emerging zoonotic parasitic infection increasingly observed in southern Europe. We report a case of a woman from western Sicily, who likely acquired the infection locally through a mosquito bite. The high prevalence of D. repens in the local canine population (up to 20.4%) suggests a role of dogs as a probable reservoir for transmission to humans in the local population. With ultrasound analysis being inconclusive, only after surgical removal was the presence of an adult worm evident, and only after molecular analysis through DNA sequencing of the cytochrome oxidase subunit I gene (COI) could a definitive D. repens infection diagnosis be obtained. This case highlights the need for enhanced vector control, animal health surveillance and public awareness to limit the transmission to humans of D. repens. A correct parasitological diagnosis would be imperative for the recognition of human cases.