Fungemia due to rare non-Candida yeasts between 2018 and 2021 in a Greek tertiary care university hospital.

INTRODUCTION: Non-Candida yeasts, although rare, are increasingly encountered and recognized as a growing threat. METHODS: Cases of bloodstream infections (BSIs) due to non-Candida yeasts (NCYs) during the last four years (2018-2021) are presented. RESULTS: During the study period, 16 cases caused by non-Candida yeasts out of 400 cases of yeast BSIs were recorded, corresponding to an incidence of 4%. Yeasts that were isolated included Cryptococcus spp (4 isolates-25%), Rhodotorula mucilaginosa (2 isolates-12.5%), Trichosporon asahii (7 isolates-43.75%) and Saccharomyces cerevisiae (3 isolates-18.75%). Predisposing factors involved mostly hematological malignancies, long term hospitalization or major surgical interventions. Most isolates, 15 out of 16 were susceptible to amphotericin B. Voriconazole was the most active azole in vitro. All isolates, except Saccharomyces spp., were resistant to echinocandins. DISCUSSION: Early recognition of rare yeasts as causative agents of BSIs and prompt initiation of appropriate treatment based on current guidelines and expertise remain crucial in efficient patient management.

Yeast Bloodstream Infections in the COVID-19 Patient: A Multicenter Italian Study (FiCoV Study).

Fungemia is a co-infection contributing to the worsening of the critically ill COVID-19 patient. The multicenter Italian observational study FiCoV aims to estimate the frequency of yeast bloodstream infections (BSIs), to describe the factors associated with yeast BSIs in COVID-19 patients hospitalized in 10 hospitals, and to analyze the antifungal susceptibility profiles of the yeasts isolated from blood cultures. The study included all hospitalized adult COVID-19 patients with a yeast BSI; anonymous data was collected from each patient and data about antifungal susceptibility was collected. Yeast BSI occurred in 1.06% of patients, from 0.14% to 3.39% among the 10 participating centers. Patients were mainly admitted to intensive or sub-intensive care units (68.6%), over 60 years of age (73%), with a mean and median time from the hospitalization to fungemia of 29 and 22 days, respectively. Regarding risk factors for fungemia, most patients received corticosteroid therapy during hospitalization (61.8%) and had a comorbidity (25.3% diabetes, 11.5% chronic respiratory disorder, 9.5% cancer, 6% haematological malignancies, 1.4% organ transplantation). Antifungal therapy was administered to 75.6% of patients, mostly echinocandins (64.5%). The fatality rate observed in COVID-19 patients with yeast BSI was significantly higher than that of COVID-19 patients without yeast BSI (45.5% versus 30.5%). Candida parapsilosis (49.8%) and C. albicans (35.2%) were the most fungal species isolated; 72% of C. parapsilosis strains were fluconazole-resistant (range 0-93.2% among the centers). The FiCoV study highlights a high prevalence of Candida BSIs in critically ill COVID-19 patients, especially hospitalized in an intensive care unit, a high fatality rate associated with the fungal co-infection, and the worrying spread of azole-resistant C. parapsilosis.

Azole resistance in Aspergillus isolates by different types of patients and correlation with environment - An Italian prospective multicentre study (ARiA study).

BACKGROUND: A wide range of frequency of azole-resistance in A fumigatus in different patient populations worldwide was observed threatening to reduce therapeutic options. OBJECTIVES: Estimate the prevalence of azole-resistance, investigate the molecular mechanisms of resistance, compare the genotypes of resistant clinical isolates with those from the surrounding environment. METHODS: Aspergillus isolates were collected by seven Italian hospital microbiology laboratories. Strains were isolated from different clinical samples from unselected patients. The azole-resistance was evaluated using screening test and microdilution EUCAST method. The molecular mechanism of resistance was performed sequencing the cyp51A gene. Resistant isolates were genotyped by microsatellite analysis and their profiles compared with those of azole-resistant isolates from previous Italian studies. RESULTS: 425 Aspergillus isolates from 367 patients were analysed. The azole-resistance rates were 4.9% and 6.6% considering all Aspergillus spp. isolates and the A fumigatus sensu stricto, respectively. All resistant isolates except one were from a single hospital. Two rare azole-resistant species were identified: A thermomutatus and A lentulus. The predominant resistance mechanism was TR34 /L98H. No correlation between the clinical resistant strains and environmental isolates from patients' home/work/ward was observed. The analysis of the molecular correlation between the resistant clinical strains collected in the present study and those of environmental and clinical origin collected in previous Italian studies reveals a progressive diversification of azole-resistant genotypes starting from a founder azole-resistant genotype. CONCLUSIONS: This study confirms the trend of azole-resistance rate in Italy, showing a geographical difference. Data reinforce the importance of surveillance programmes to monitor the local epidemiological situation.

Epidemiological characteristics of cryptococcal meningoencephalitis associated with Cryptococcus neoformans var. grubii from HIV-infected patients in Madagascar: A cross-sectional study.

Cryptococcal meningoencephalitis (CM) remains the most prevalent invasive fungal infection worldwide. The main objective of this study was to describe the prevalence of CM and cryptococcal infection in HIV-infected patients in Madagascar. The secondary objectives were to assess the adjusted prevalence of CM according to clinical presentation and patient characteristics, to determine crude 90-day survival according to cryptococcal antigen (CrAg) status and CM, and to identify the genotypes of Cryptococcus clinical isolates. This cross-sectional study was carried out at two urban hospitals in Antananarivo (central highlands) and Toamasina (east coast) between November 2014 and December 2016. Consecutive HIV-infected adults presenting with CD4 cell counts ≤200/µl were enrolled. Lateral flow immunoassays of CrAg were performed on serum for all patients, and on cerebrospinal fluid for patients with CM symptoms. MALDI-ToF MS, ITS sequencing, and determinations of the molecular and mating types of the isolates were performed. Fluconazole is the only drug for CM treatment available in Madagascar. Patients were treated orally, with high doses (1200 mg/day) for 10-12 weeks and then with 200 mg/day. Minimum inhibitory concentrations were determined for amphotericin B, flucytosine, voriconazole and fluconazole in E-tests. Overall prevalence was 13.2% (95% CI 7.9-20.3) for cryptococcal infection and 10.9% (95% CI 6.1-17.5) for CM, among the 129 HIV-infected patients studied. The 90-day mortality rate was 58.8% (10/17) in CrAg-positive patients and 17.9% (20/112) in CrAg-negative patients (p<0.001). The 13 Cryptococcus strains obtained at baseline were all Cryptococcus neoformans var. grubii, genotypes VNI-αA (3 isolates), VNII-αA (4 isolates) or hybrid VNI/VNII-αAAα (6 isolates), suggesting high diversity. Two strains acquired fluconazole resistance after four and five months of exposure, respectively. The prevalence of cryptococcosis is high in Madagascar and this serious condition is life-threatening in HIV-infected patients. These findings will be used to raise the awareness of national authorities to strengthen the national HIV/AIDS control program.

Epidemiological trends of cryptococcosis in Italy: Molecular typing and susceptibility pattern of Cryptococcus neoformans isolates collected during a 20-year period.

In the present study clinical data and isolates from cases of cryptococcosis recorded during clinical surveys carried out in Italy from 1997 to 2016, were investigated. Molecular typing and antifungal susceptibility testing were performed in order to delineate the epidemiological trend of cryptococcosis in Italy and to define wild-type population for four different antifungal compounds. During the studied period, a total of 302 cases collected from 32 centers of 11 Italian regions were recorded. Analysis of clinical data showed a significant increase of frequency (from 7% to 38%) of cryptococcosis in human immunodeficiency virus (HIV)-negative patients primarily with hematologic malignancies and solid organ transplantations. The prevalence of the molecular types has significantly changed during the study period, showing an increase of VNIII isolates from 11% to 41% in HIV-negative patients, and a decrease of VNIV isolates from 36% to 16%. Antifungal susceptibility testing allowed us to calculate the epidemiological cut-off for flucytosine (1 mg/l), fluconazole (8 mg/l), itraconazole (0.5 mg/l), and voriconazole (0.25 mg/l). Most of the isolates were wild-type strains. Comparison of the MIC distributions according to molecular types showed that VNIV isolates had lower MICs for fluconazole and itraconazole than the VNI and VIII isolates. The current study emphasizes that the epidemiology of cryptococcosis in Italy has significantly changed over the last decades.

Determining the analytical specificity of PCR-based assays for the diagnosis of IA: What is Aspergillus?

A wide array of PCR tests has been developed to aid the diagnosis of invasive aspergillosis (IA), providing technical diversity but limiting standardisation and acceptance. Methodological recommendations for testing blood samples using PCR exist, based on achieving optimal assay sensitivity to help exclude IA. Conversely, when testing more invasive samples (BAL, biopsy, CSF) emphasis is placed on confirming disease, so analytical specificity is paramount. This multicenter study examined the analytical specificity of PCR methods for detecting IA by blind testing a panel of DNA extracted from a various fungal species to explore the range of Aspergillus species that could be detected, but also potential cross reactivity with other fungal species. Positivity rates were calculated and regression analysis was performed to determine any associations between technical specifications and performance. The accuracy of Aspergillus genus specific assays was 71.8%, significantly greater (P < .0001) than assays specific for individual Aspergillus species (47.2%). For genus specific assays the most often missed species were A. lentulus (25.0%), A. versicolor (24.1%), A. terreus (16.1%), A. flavus (15.2%), A. niger (13.4%), and A. fumigatus (6.2%). There was a significant positive association between accuracy and using an Aspergillus genus PCR assay targeting the rRNA genes (P = .0011). Conversely, there was a significant association between rRNA PCR targets and false positivity (P = .0032). To conclude current Aspergillus PCR assays are better suited for detecting A. fumigatus, with inferior detection of most other Aspergillus species. The use of an Aspergillus genus specific PCR assay targeting the rRNA genes is preferential.

A case of Histoplasma capsulatum endophthalmitis diagnosed in Italy.

Histoplasma capsulatum var. capsulatum is a dimorphic fungus endemic in the eastern United States and most countries of Latin America. Sporadic cases of histoplasmosis have been reported in Europe, mainly in immigrants or people returning from highly endemic areas. We report a case of 64-year-old Italian man with endophthalmitis, an unusual presentation of H. capsulatum infection. The patient shows redness, blurred vision, localized pain in the right eye. H. capsulatum was cultured from a vitreous biopsy and yeast forms were seen at histology.

Four-year persistence of a single Candida albicans genotype causing bloodstream infections in a surgical ward proven by multilocus sequence typing.

The present study represents the first application of multilocus sequence typing to retrospectively investigate a suspected outbreak of Candida albicans bloodstream infection cases that occurred in the same hospital ward between July 1987 and October 1991. Results demonstrated that eight bloodstream infections were caused by the same strain, endemic in the ward, over a 4-year period.