Fluconazole-resistant Candida parapsilosis genotypes from hospitals located in five Spanish cities and one in Italy: Description of azole-resistance profiles associated with the Y132F ERG11p substitution.

BACKGROUND: Fluconazole-resistant Candida parapsilosis is a matter of concern. OBJECTIVES: To describe fluconazole-resistant C. parapsilosis genotypes circulating across hospitals in Spain and Rome and to study their azole-resistance profile associated with ERG11p substitutions. PATIENTS/METHODS: We selected fluconazole-resistant C. parapsilosis isolates (n = 528 from 2019 to 2023; MIC ≥8 mg/L according to EUCAST) from patients admitted to 13 hospitals located in five Spanish cities and Rome. Additionally, we tested voriconazole, posaconazole, isavuconazole, amphotericin B, micafungin, anidulafungin and ibrexafungerp susceptibility. RESULTS: Of the 53 genotypes found, 49 harboured the Y132F substitution, five of which were dominating city-specific genotypes involving almost half the isolates. Another genotype involved isolates harbouring the G458S substitution. Finally, we found two genotypes with the wild-type ERG11 gene sequence and one with the R398I substitution. All isolates were fully susceptible/wild-type to amphotericin B, anidulafungin, micafungin and ibrexafungerp. The azole-resistance patterns found were: voriconazole-resistant (74.1%) or voriconazole-intermediate (25.2%), posaconazole-resistant (10%) and isavuconazole non-wild-type (47.5%). Fluconazole-resistant and voriconazole non-wild-type isolates were likely to harbour substitution Y132F if posaconazole was wild type; however, if posaconazole was non-wild type, substitution G458S was indicated if isavuconazole MIC was >0.125 mg/L or substitution Y132F if isavuconazole MIC was ≤0.125 mg/L. CONCLUSIONS: We detected a recent clonal spread of fluconazole-resistant C. parapsilosis across some cities in Spain, mostly driven by dominating city-specific genotypes, which involved a large number of isolates harbouring the Y132F ERG11p substitution. Isolates harbouring substitution Y132F can be suspected because they are non-susceptible to voriconazole and rarely posaconazole-resistant.

Aspergillus granulosus femoral osteomyelitis in a cardiac transplant patient: first reported case and literature review.

Aspergillus osteomyelitis is a rare complication of extrapulmonary invasive aspergillosis, which usually presents as spondylodiscitis. The clinical picture is usually paucisymptomatic and of long evolution, which leads to diagnostic difficulties, especially in immunosuppressed patients presenting a delayed systemic host response. We report a case of femoral osteomyelitis caused by Aspergillus granulosus in a heart transplant recipient successfully treated with a combined surgical and antifungal approach. A 65-year-old heart transplant male presented with left knee pain lasting 3 months. X-ray and magnetic resonance imaging identified a lesion with aggressive characteristics at the distal third of the left femur, due to which the patient underwent excisional surgery. Aspergillus granulosus was cultured from the removed material and antifungal treatment with oral isavuconazole was started. Chest imaging excluded pulmonary aspergillosis, while the positron emission tomography/computed tomography (PET/CT) identified a remnant of a prosthetic vascular graft sewn to the proximal third of the right axillary artery, through which a catheter-based micro-axial left ventricular assist device was implanted previously as bridge to transplant therapy. The patient presented a rapid clinical improvement with complete functional recovery following the surgical treatment and the antifungal therapy and finally underwent surgical removal of the residual vascular graft. This is the first reported episode of long bone osteomyelitis due to A. granulosus that occurred in a heart transplant recipient without pulmonary infection and was successfully treated with isavuconazole. The PET/CT was useful in supporting the diagnostic process and follow-up. Cryptic fungal species can cause invasive infections, particularly in immunocompromised patients. Molecular methods are crucial in fungal identification.

Clonal spread of fluconazole-resistant C. parapsilosis in patients admitted to a referral hospital located in Burgos, Spain, during the COVID-19 pandemic.

BACKGROUND: Fluconazole-resistant Candida parapsilosis (FRCP) is a matter of concern in Spain. OBJECTIVES: We here report a FRCP spread across a 777-bed referral hospital located in Burgos, Spain, during the COVID-19 pandemic. PATIENTS/METHODS: In April 2021, an FRCP isolate (MIC = 64 mg/L, E-test®) from a hospitalised patient was detected. Up to June 2022, all C. parapsilosis isolates (n = 35) from hospitalised patients (n = 32) were stored and genotyped using microsatellite markers, and their antifungal susceptibilities were studied (EUCAST); FRCP isolates were molecularly characterised. RESULTS: We detected 26 FRCP isolates collected between 2021 (n = 8) and 2022 (n = 18); isolates were susceptible to amphotericin B, echinocandins and ibrexafungerp. FRCP isolates were grouped into three genotypes: CP-707 and CP-708 involved isolates harbouring the Y132F + R398I ERG11p substitutions (n = 24) and were clonally related; the remaining CP-675 genotype involved isolates harbouring the G458S ERG11p substitution (n = 2). FRCP genotypes were genetically related to the FRCP genotypes found in Madrid and were unrelated to fluconazole-susceptible ones. Patients harbouring FRCP were mainly (n = 22/23) admitted to intensive care units. Most patients had received broad-spectrum antibiotics (n = 22/23), and/or antifungal therapy with azoles (n = 14/23) within the 30 days prior to FRCP isolation. Thirteen patients were colonised, 10 of whom were infected and presented candidaemia (n = 8/10), endovascular infection (n = 1/10) or complicated urinary infection (n = 1/10). Overall nonattributable 30-day mortality was 17% (n = 4/23). CONCLUSIONS: We report an outbreak caused by FRCP affecting patients admitted to the ICU of a referral hospital located in Burgos. Patients harbouring FRCP had a higher fluconazole use than those carrying susceptible isolates.

Trends in antifungal resistance in Candida from a multicenter study conducted in Madrid (CANDIMAD study): fluconazole-resistant C. parapsilosis spreading has gained traction in 2022.

We previously conducted a multicenter surveillance study on Candida epidemiology and antifungal resistance in Madrid (CANDIMAD study; 2019-2021), detecting an increase in fluconazole-resistant Candida parapsilosis. We here present data on isolates collected in 2022. Furthermore, we report the epidemiology and antifungal resistance trends during the entire period, including an analysis per ward of admission. Candida spp. incident isolates from blood cultures and intra-abdominal samples from patients cared for at 16 hospitals in Madrid, Spain, were tested with the EUCAST E.Def 7.3.2 method against amphotericin B, azoles, micafungin, anidulafungin, and ibrexafungerp and were molecularly characterized. In 2022, we collected 766 Candida sp. isolates (686 patients; blood cultures, 48.8%). Candida albicans was the most common species found, and Candida auris was undetected. No resistance to amphotericin B was found. Overall, resistance to echinocandins was low (0.7%), whereas fluconazole resistance was 12.0%, being higher in blood cultures (16.0%) mainly due to fluconazole-resistant C. parapsilosis clones harboring the Y132F-R398I ERG11p substitutions. Ibrexafungerp showed in vitro activity against the isolates tested. Whereas C. albicans was the dominant species in most hospital wards, we observed increasing C. parapsilosis proportions in blood. During the entire period, echinocandin resistance rates remained steadily low, while fluconazole resistance increased in blood from 6.8% (2019) to 16% (2022), mainly due to fluconazole-resistant C. parapsilosis (2.6% in 2019 to 36.6% in 2022). Up to 7 out of 16 hospitals were affected by fluconazole-resistant C. parapsilosis. In conclusion, rampant clonal spreading of C. parapsilosis fluconazole-resistant genotypes is taking place in Madrid.

Recommendations of the Spanish Antibiogram Committee (COESANT) for in vitro susceptibility testing of antimicrobial agents by disk diffusion / Recomendaciones del Comité Español del Antibiograma (COESANT) para el estudio de sensibilidad in vitro a los antimicrobianos por difusión con discos

Disk diffusion is a well standardized method that provides reliable categorical results to guide antimicrobial therapy in numerous types of infections. Based on the guidelines of the European Committee on Antimicrobial Susceptibility Testing (EUCAST), which are widely implemented in Spain, the Spanish Antibiogram Committee (COESANT) has drawn up recommendations for antimicrobial selection by the disk diffusion technique, including selective reporting and its use for the detection of resistance mechanisms. Factors affecting disk diffusion results, along with advantages and shortcomings of the method, are also discussed.(AU)

La difusión con discos es un método estandarizado que proporciona resultados fiables para guiar la terapia antimicrobiana en numerosos tipos de infecciones. En base a las directrices del European Committee on Antimicrobial Susceptibility Testing (EUCAST), ampliamente implantadas en España, el Comité Español del Antibiograma (COESANT) ha elaborado recomendaciones para la selección de antimicrobianos para ser estudiados mediante la técnica de difusión con discos, su notificación selectiva en el informe de sensibilidad y su uso para la detección de mecanismos de resistencia. También se discuten los factores que afectan los resultados obtenidos mediante la técnica de difusión con discos junto con las ventajas y desventajas del método.(AU)

Recomendaciones del Comité Español del Antibiograma (COESANT) para la realización de los Informes de Sensibilidad Antibiótica Acumulada / Spanish Antibiogram Committee (COESANT) recommendations for cumulative antibiogram reports

El Comité Español del Antibiograma (COESANT) presenta en este documento una serie de recomendaciones cuya finalidad es unificar la forma en la que los Servicios y Unidades de Microbiología Clínica españoles realizan los informes de sensibilidad acumulada de las bacterias, aisladas en muestras clínicas, frente a los antimicrobianos. Las recomendaciones se fundamentan en las recogidas en el Procedimiento de Microbiología Clínica n° 51, «Preparación de informes acumulados de sensibilidad a los antimicrobianos» de la Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC), publicado en 2014, y recoge las modificaciones en las definiciones de las interpretaciones de las categorías clínicas publicadas en el año 2019 por el European Committee on Antimicrobial Susceptibility Testing (EUCAST). Su objetivo final es establecer una forma homogénea de elaborar estos resúmenes para poder comparar resultados de diferentes centros o sumar su información y así realizar una adecuada vigilancia local o incluso nacional de la evolución de la sensibilidad a los antimicrobianos.(AU)

The Spanish Antibiogram Committee (Comité Español del Antibiograma, COESANT) presents in this document a series of recommendations intending to unify how cumulative antibiogram reports must be made in Clinical Microbiology Spanish laboratories. This article is based on the information included in the Clinical Microbiology Procedure No. 51, «Preparation of cumulative reports on antimicrobial susceptibility» of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), published in 2014. The recommendations also include the modifications in the definition of clinical interpretive categories recently published by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) in 2019. Its final objective is to establish a homogeneous way of preparing these summaries to compare results from different centers or aggregate the information from these in order to carry out an adequate local or even national surveillance regarding the evolution of antimicrobial susceptibility.(AU)

Antifungal resistance in Candida spp within the intra-abdominal cavity: study of resistance acquisition in patients with serial isolates.

OBJECTIVES: Antifungal susceptibility testing is mostly conducted on blood-cultured Candida spp isolates. Because the intra-abdominal cavity has been highlighted as a hidden echinocandin-resistant C. glabrata reservoir, we assessed whether testing sequential isolates from a given patient might increase the chances of detecting antifungal resistance. METHODS: Intra-abdominal initial and sequential isolates from the same species from patients included in the CANDIdaemia in MADrid study (January 2019 to June 2022) were studied. We assessed antifungal susceptibility to amphotericin B, azoles, anidulafungin, micafungin, and ibrexafungerp using European Committee on Antimicrobial Susceptibility Testing (EUCAST) methodology and molecularly characterized resistant isolates. RESULTS: We collected 308 isolates (C. albicans [n = 179/308; 58.1%], C. glabrata [n = 101/308; 32.8%], C. tropicalis [n = 17/308; 5.5%], and C. parapsilosis [n = 11/308; 3.6%]) from 112 patients distributed as incident (n = 125/308) and sequential (n = 183/308). Per patient resistance rates of fluconazole (13.4% [15/112] vs. 8% [9/112]); 5.4% proportions difference (95% CI, -2.7% to 13.5%, p 0.09) and echinocandins (8.9% [10/112] vs. 1.8% [2/112]); 7.1% proportions difference (95% CI; 1.2-12.9%; p 0.01) were higher when considering all available isolates than only incident isolates. Resistance was detected in 18 of 112 patients and would have been overlooked in 11 of 18 (61.1%) patients if only incident isolates had been studied. Of the patients who harboured fluconazole or echinocandin-resistant isolates, 14 of 15 and 8 of 10 had received or were receiving fluconazole or echinocandins, respectively. DISCUSSION: Testing sequential Candida isolates from intra-abdominal samples is required to detect antifungal resistance, particularly to echinocandins, in patients whose incident isolates turned out to be susceptible. Furthermore, patients with echinocandin-resistant infections had frequently used echinocandins and had common secondary resistance acquisition.

Yeasts from blood cultures in the wake of the COVID-19 pandemic in a tertiary care hospital: Shift in species epidemiology, steady low antifungal resistance and full in vitro ibrexafungerp activity.

Several institutions reported a rise not only in fungemia incidence but also in the number of cases caused by Candida auris or fluconazole-resistant C. parapsilosis during the COVID-19 pandemic. Since the pandemic broke out in early 2020, we studied its impact on fungemia incidence, species epidemiology, potential patient-to-patient transmission, and antifungal resistance in 166 incident yeast isolates collected from January 2020 to December 2022. Isolates were molecularly identified, and their antifungal susceptibilities to amphotericin B, azoles, micafungin, anidulafungin, and ibrexafungerp were studied following the European Committee on Antimicrobial Susceptibility Testing (EUCAST) method, and genotyped. The fungemia incidence (episodes per 1000 admissions) tended to decrease over time (2020 = 1.60, 2021 = 1.36, 2022 = 1.16); P > .05). Species distribution was C. albicans (50.6%, n = 84), C. parapsilosis (18.7%, n = 31), C. glabrata (12.0%, n = 20), C. tropicalis (11.4%, n = 19), C. krusei (3.0%, n = 5), other Candida spp. (1.2%, n = 2), and non-Candida yeasts (3.0%, n = 5). The highest and lowest proportions of C. albicans and C. parapsilosis were detected in 2020. The proportion of isolates between 2020 and 2022 decreased in C. albicans (60.3% vs. 36.7%) and increased in C. parapsilosis (10.3% vs. 28.6%; P < .05) and C. tropicalis (8.8% vs. 16.3%; P > .05). Only three C. albicans intra-ward clusters involving two patients each were detected, and the percentages of patients involved in intra-ward clusters reached 9.8% and 8.0% in 2020 and 2021, respectively, suggesting that clonal spreading was not uncontrolled. Fluconazole resistance (5%) exhibited a decreasing trend (P > .05) over time (2020 = 7.6%; 2021 = 4.2%; and 2022 = 2.1%). Ibrexafungerp showed high in vitro activity.

Fungemia incidence increased during the COVID-19 pandemic in our hospital, however, clonal spreading was not uncontrolled. The proportion of C. parapsilosis and C. tropicalis cases constantly increased. Antifungal resistance remained very low, and fluconazole-resistant C. parapsilosis was undetected.

The Gastrointestinal Tract Is Pinpointed as a Reservoir of Candida albicans, Candida parapsilosis, and Candida tropicalis Genotypes Found in Blood and Intra-Abdominal Samples.

BACKGROUND: Candida spp., as part of the microbiota, can colonise the gastrointestinal tract. We hypothesised that genotyping Candida spp. isolates from the gastrointestinal tract could help spot genotypes able to cause invasive infections. MATERIALS/METHODS: A total of 816 isolates of C. albicans (n = 595), C. parapsilosis (n = 118), and C. tropicalis (n = 103) from rectal swabs (n = 754 patients) were studied. Genotyping was conducted using species-specific microsatellite markers. Rectal swab genotypes were compared with previously studied blood (n = 814) and intra-abdominal (n = 202) genotypes. RESULTS: A total of 36/754 patients had the same Candida spp. isolated from blood cultures, intra-abdominal samples, or both; these patients had candidemia (n = 18), intra-abdominal candidiasis (n = 11), both clinical forms (n = 1), and non-significant isolation (n = 6). Genotypes matching the rectal swab and their blood cultures (84.2%) or their intra-abdominal samples (92.3%) were found in most of the significant patients. We detected 656 genotypes from rectal swabs, 88.4% of which were singletons and 11.6% were clusters. Of these 656 rectal swab genotypes, 94 (14.3%) were also detected in blood cultures and 34 (5.2%) in intra-abdominal samples. Of the rectal swab clusters, 62.7% were previously defined as a widespread genotype. CONCLUSIONS: Our study pinpoints the gastrointestinal tract as a potential reservoir of potentially invasive Candida spp. genotypes.

In vitro study to assess modulation of Candida biofilm by Escherichia coli from vaginal strains.

Background: Vulvovaginal candidiasis (VVC) is caused by biofilm formation and epithelial invasion. In addition, Escherichia coli (EC) can establish a vaginal intracellular reservoir modulating Candida spp. biofilm production. We aimed to analyze the behavior of Candida albicans (CA) and EC biofilm both in single cultures and in co-cultures. Methods: We prospectively collected CA and EC isolates from vaginal swabs over 6 months. We selected positive cultures with both CA and EC (cases) and a comparator group with either CA or EC (controls). We analyzed overall biomass production and metabolic activity in single cultures and in co-cultures based on staining assays, confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) to assess biofilm occupation. We also analyzed clinical manifestations. Results: We cultured 455 samples, 16 (3.5%) of which had CA and EC (cases); only CA or EC (controls) was detected, respectively, in 72 (15.8%) and 98 (21.5%). Biomass production and metabolic activity were significantly more pronounced in co-cultures in both groups. CLSM and SEM, on the other hand, showed the biofilm of each species to be significantly reduced when they were cultured together, with higher values in CA (percentage biofilm reduction: CA, 95.8% vs. EC, 36.2%, p < 0.001). There were no clinically significant differences between co-infected patients and patients infected only by C. albicans. Conclusion: Ours is the first study assessing co-cultures of CA and EC in a large collection of samples. We observed that coinfection of CA and EC was unusual (3.5%) and promoted high biomass, whereas microscopy enabled us to detect a reduction in biofilm production when microorganisms were co-cultured. No differences in symptoms were observed.

Breakthrough invasive fungal infection among patients with haematologic malignancies: A national, prospective, and multicentre study.

OBJECTIVES: We describe the current epidemiology, causes, and outcomes of breakthrough invasive fungal infections (BtIFI) in patients with haematologic malignancies. METHODS: BtIFI in patients with ≥ 7 days of prior antifungals were prospectively diagnosed (36 months across 13 Spanish hospitals) according to revised EORTC/MSG definitions. RESULTS: 121 episodes of BtIFI were documented, of which 41 (33.9%) were proven; 53 (43.8%), probable; and 27 (22.3%), possible. The most frequent prior antifungals included posaconazole (32.2%), echinocandins (28.9%) and fluconazole (24.8%)-mainly for primary prophylaxis (81%). The most common haematologic malignancy was acute leukaemia (64.5%), and 59 (48.8%) patients had undergone a hematopoietic stem-cell transplantation. Invasive aspergillosis, principally caused by non-fumigatus Aspergillus, was the most frequent BtIFI with 55 (45.5%) episodes recorded, followed by candidemia (23, 19%), mucormycosis (7, 5.8%), other moulds (6, 5%) and other yeasts (5, 4.1%). Azole resistance/non-susceptibility was commonly found. Prior antifungal therapy widely determined BtIFI epidemiology. The most common cause of BtIFI in proven and probable cases was the lack of activity of the prior antifungal (63, 67.0%). At diagnosis, antifungal therapy was mostly changed (90.9%), mainly to liposomal amphotericin-B (48.8%). Overall, 100-day mortality was 47.1%; BtIFI was either the cause or an essential contributing factor to death in 61.4% of cases. CONCLUSIONS: BtIFI are mainly caused by non-fumigatus Aspergillus, non-albicans Candida, Mucorales and other rare species of mould and yeast. Prior antifungals determine the epidemiology of BtIFI. The exceedingly high mortality due to BtIFI warrants an aggressive diagnostic approach and early initiation of broad-spectrum antifungals different than those previously used.

Amphotericin B, itraconazole, posaconazole, and isavuconazole MICs against clinical Mucorales isolates obtained by visual inspection and spectrophotometric reading according to the EUCAST 9.4 procedure.

We compared the antifungal susceptibility of 92 Mucorales isolates obtained by visual inspection and spectrophotometric readings following EUCAST (European Committee on Antimicrobial Susceptibility Testing) testing. Amphotericin B minimum inhibitory concentrations (MICs) were up to 1 mg/l against most isolates and variable among species, except for Cunninghamella bertholletiae. Posaconazole MICs against most isolates were up to 1 mg/l and high against Mucor circinelloides, some Rhizopus arrhizus, and Rhizopus microsporus. Isavuconazole MICs ranged between 1 and 8 mg/l but were invariably >8 mg/l against M. circinelloides and C. bertholletiae. The agreement between MICs obtained by visual endpoint or spectrophotometric readings was moderate and higher when using the ≥90% fungal growth inhibition endpoint.

The agreement between minimum inhibitory concentration (MIC) values obtained by visual inspection or spectrophotometric readings was moderate and higher when the ≥90% fungal growth inhibition endpoint was chosen. Isavuconazole presented higher MICs than posaconazole, regardless of the inhibition endpoint used.

Correction: Díaz-García et al. Candida Genotyping of Blood Culture Isolates from Patients Admitted to 16 Hospitals in Madrid: Genotype Spreading during the COVID-19 Pandemic Driven by Fluconazole-Resistant C. parapsilosis. J. Fungi 2022, 8, 1228.

In the original publication [...].

Recommendations of the Spanish Antibiogram Committee (COESANT) for in vitro susceptibility testing of antimicrobial agents by disk diffusion.

Disk diffusion is a well standardized method that provides reliable categorical results to guide antimicrobial therapy in numerous types of infections. Based on the guidelines of the European Committee on Antimicrobial Susceptibility Testing (EUCAST), which are widely implemented in Spain, the Spanish Antibiogram Committee (COESANT) has drawn up recommendations for antimicrobial selection by the disk diffusion technique, including selective reporting and its use for the detection of resistance mechanisms. Factors affecting disk diffusion results, along with advantages and shortcomings of the method, are also discussed.

Gradient diffusion strips for detecting azole resistance in Aspergillus fumigatus sensu lato.

BACKGROUND: Studies comparing gradient diffusion strips (GDSs) and the EUCAST E.Def 9.4 microdilution method are scarce, thwarted by a low number of isolates, and restricted to selected antifungal agents. OBJECTIVES: We evaluated the performance of GDSs to detect azole resistance in A. fumigatus, including cryptic species. PATIENTS/METHODS: A. fumigatus sensu stricto (n = 89) and cryptic species (n = 52) were classified as susceptible or resistant to itraconazole, voriconazole, posaconazole and isavuconazole (EUCAST E.Def 9.4; clinical breakpoints v10). A. fumigatus sensu stricto azole-resistant isolates had the following cyp51A gene mutations: TR34 -L98H (n = 24), G54R (n = 5), TR46 -Y121F-T289A (n = 1), F46Y-M172V-N248T-D255E-E427K (n = 1), F165L (n = 1) and cyp51A gene wild type (n = 3). GDSs (ETEST®, bioMèrieux, Marcy-l'Etoile, France and Liofilchem®, Roseto degli Abruzzi, Italy) MICs were obtained by following the manufacturer's guidelines. RESULTS: For A. fumigatus sensu stricto, itraconazole MICs >1.5 mg/L, voriconazole >0.38 mg/L, posaconazole >0.75 mg/L, and isavuconazole >0.5 mg/L correctly separated resistant from susceptible isolates with two exceptions. Considering the aforementioned cut-off MICs, sensitivity/specificity values of GDSs to detect azole resistance were: itraconazole (97%/100%), voriconazole (97%/100%), posaconazole (97%/100%) and isavuconazole (93.3%/100%). For cryptic species isolates, voriconazole MICs >1 mg/L and isavuconazole >0.75 mg/L separated resistant isolates from susceptible isolates with 15 and 27 exceptions, respectively. Considering the aforementioned cut-off MICs, sensitivity/specificity values were as follows: voriconazole (68.1%/100%) and isavuconazole (25%/100%). For itraconazole and posaconazole, it was not possible to establish cut-off values. CONCLUSIONS: We set tentative cut-off MIC values to correctly spot resistant Aspergillus fumigatus sensu stricto isolates using GDSs. The performance against cryptic species was poor.

Spanish Antibiogram Committee (COESANT) recommendations for cumulative antibiogram reports.

The Spanish Antibiogram Committee (Comité Español del Antibiograma, COESANT) presents in this document a series of recommendations intending to unify how cumulative antibiogram reports must be made in Clinical Microbiology Spanish laboratories. This article is based on the information included in the Clinical Microbiology Procedure No. 51, «Preparation of cumulative reports on antimicrobial susceptibility¼ of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), published in 2014. The recommendations also include the modifications in the definition of clinical interpretive categories recently published by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) in 2019. Its final objective is to establish a homogeneous way of preparing these summaries to compare results from different centers or aggregate the information from these in order to carry out an adequate local or even national surveillance regarding the evolution of antimicrobial susceptibility.

Global Emergence of Resistance to Fluconazole and Voriconazole in Candida parapsilosis in Tertiary Hospitals in Spain During the COVID-19 Pandemic.

Background: Candida parapsilosis is a frequent cause of candidemia worldwide. Its incidence is associated with the use of medical implants, such as central venous catheters or parenteral nutrition. This species has reduced susceptibility to echinocandins, and it is susceptible to polyenes and azoles. Multiple outbreaks caused by fluconazole-nonsusceptible strains have been reported recently. A similar trend has been observed among the C. parapsilosis isolates received in the last 2 years at the Spanish Mycology Reference Laboratory. Methods: Yeast were identified by molecular biology, and antifungal susceptibility testing was performed using the European Committee on Antimicrobial Susceptibility Testing protocol. The ERG11 gene was sequenced to identify resistance mechanisms, and strain typing was carried out by microsatellite analysis. Results: We examined the susceptibility profile of 1315 C. parapsilosis isolates available at our reference laboratory between 2000 and 2021, noticing an increase in the number of isolates with acquired resistance to fluconazole, and voriconazole has increased in at least 8 different Spanish hospitals in 2020-2021. From 121 recorded clones, 3 were identified as the most prevalent in Spain (clone 10 in Catalonia and clone 96 in Castilla-Leon and Madrid, whereas clone 67 was found in 2 geographically unrelated regions, Cantabria and the Balearic Islands). Conclusions: Our data suggest that concurrently with the coronavirus disease 2019 pandemic, a selection of fluconazole-resistant C. parapsilosis isolates has occurred in Spain, and the expansion of specific clones has been noted across centers. Further research is needed to determine the factors that underlie the successful expansion of these clones and their potential genetic relatedness.

Candida Genotyping of Blood Culture Isolates from Patients Admitted to 16 Hospitals in Madrid: Genotype Spreading during the COVID-19 Pandemic Driven by Fluconazole-Resistant C. parapsilosis.

BACKGROUND: Candidaemia and invasive candidiasis are typically hospital-acquired. Genotyping isolates from patients admitted to different hospitals may be helpful in tracking clones spreading across hospitals, especially those showing antifungal resistance. METHODS: We characterized Candida clusters by studying Candida isolates (C. albicans, n = 1041; C. parapsilosis, n = 354, and C. tropicalis, n = 125) from blood cultures (53.8%) and intra-abdominal samples (46.2%) collected as part of the CANDIMAD (Candida in Madrid) study in Madrid (2019-2021). Species-specific microsatellite markers were used to define the genotypes of Candida spp. found in a single patient (singleton) or several patients (cluster) from a single hospital (intra-hospital cluster) or different hospitals (widespread cluster). RESULTS: We found 83 clusters, of which 20 were intra-hospital, 49 were widespread, and 14 were intra-hospital and widespread. Some intra-hospital clusters were first detected before the onset of the COVID-19 pandemic, but the number of clusters increased during the pandemic, especially for C. parapsilosis. The proportion of widespread clusters was significantly higher for genotypes found in both compartments than those exclusively found in either the blood cultures or intra-abdominal samples. Most C. albicans- and C. tropicalis-resistant genotypes were singleton and presented exclusively in either blood cultures or intra-abdominal samples. Fluconazole-resistant C. parapsilosis isolates belonged to intra-hospital clusters harboring either the Y132F or G458S ERG11p substitutions; the dominant genotype was also widespread. CONCLUSIONS: the number of clusters-and patients involved-increased during the COVID-19 pandemic mainly due to the emergence of fluconazole-resistant C. parapsilosis genotypes.

Multicentre validation of a modified EUCAST MIC testing method and development of associated epidemiologic cut-off (ECOFF) values for rezafungin.

OBJECTIVES: Rezafungin EUCAST MIC testing has been associated with notable inter-laboratory variation, which prevented ECOFF setting for C. albicans. We assessed in vitro susceptibility and reproducibility for a modified EUCAST methodology and established associated wild-type upper limits (WT-ULs). METHODS: MICs against 150 clinical Candida isolates (six species), molecularly characterized fks mutants (n = 13), and QC strains (n = 6) were determined at six laboratories according to E.Def 7.3 but using Tween 20 supplemented medium. WT-ULs were determined using the derivatization method, the ECOFFinder programme and visual inspection. Consensus WT-ULs were determined. RESULTS: The laboratory- and species-specific MIC distributions were Gaussian with >99.5% MICs within four 2-fold dilutions except for C. parapsilosis (92.8%). The following consensus WT-UL were determined: C. albicans 0.008 mg/L; C. dubliniensis and C. glabrata 0.016 mg/L; C. krusei and C. tropicalis 0.03 mg/L; and C. parapsilosis 4 mg/L. Adopting these WT-UL, six clinical isolates were non-wild-type, five of which harboured Fks alterations. For 11/13 mutants, all 670 MICs were categorized as non-wild-type whereas MICs for C. glabrata Fks2 D666Y and C. tropicalis Fks1 R656R/G overlapped with the corresponding wild-type distributions. Repeat testing of six reference strains yielded 98.3%-100% of MICs within three 2-fold dilutions except for C. albicans CNM-CL-F8555 (96%) and C. parapsilosis ATCC 22019 (93.3%). CONCLUSIONS: The modified EUCAST method significantly improved inter-laboratory variation, identified wild-type populations and allowed perfect separation of wild-type and fks mutants except for two isolates harbouring weak mutations. These consensus WT-UL have been accepted as ECOFFs and will be used for rezafungin breakpoint setting.