Editorial: Candida biofilms

Navigating dual-species fungal biofilms: The competitive and cooperative dynamics of Candidaalbicans

Research on microbial biofilms has primarily concentrated on bacterial-bacterial and bacterial-fungal interactions, leaving fungal-fungal dynamics underexplored. The present study examines interactions within dual-species fungal biofilms, with a particular emphasis on Candida albicans. The behavior and pathogenicity of this yeast are significantly influenced by its interactions with other fungal species in biofilms, where its ability to shift between yeast and hyphal forms contributes significantly to biofilm formation. These fungal species biofilms exhibit a complex interplay of synergistic cooperation and antagonistic competition, depending on the environmental context and resource availability. Understanding these interactions is essential for advancing our knowledge of fungal biofilm.

Elimination of Candida Sepsis and Reducing Several Morbidities in a Tertiary NICU in Greece After Changing Antibiotic, Ventilation, and Nutrition Protocols

BACKGROUND/OBJECTIVES

In recent years, strategies for improving outcomes in preterm neonates have been implemented in various aspects of neonatal care. This study aims to determine the prevalence, microbiology, and outcomes of late-onset sepsis (LOS) and the incidence of other morbidities in very preterm neonates following the implementation of specific infection control, enteral feeding, and ventilation strategies.

METHODS

This study retrospectively compared the morbidity and mortality of preterm neonates with a 23-32 weeks gestational age over two periods, period A (2010-2014),and period B (2018-2022). A series of changes were introduced between these periods, including restrictive use of antibiotics, aggressive enteral feeding, and wider use of non-invasive ventilation modalities.

RESULTS

A total of 310 neonates were included: 163 in period A and 147 in period B. The mean duration of antibiotic treatment was reduced from 4 ± 2 to 2 ± 1 days and from 5 ± 2 to 3 ± 1 days for suspected early-onset sepsis and LOS, respectively, and from 11.2 ± 4 to 16 ± 4 days for confirmed LOS between the two study periods. The incidence of LOS was 24% and 18%, while, for multiple LOS episodes, it was 26% and 11% in periods A and B, respectively. Total parenteral nutrition (TPN) duration and gestational age were independent predictors of LOS in both periods. The rate of Candida infections declined from 9.2% to 0.7%. The full enteral nutrition in period B was achieved after a median of 7.5 days compared with 10 days (p = 0.001), resulting in fewer days of TPN (p = 0.008). Episodes of feeding intolerance and necrotizing enterocolitis I (NEC I) were significantly reduced (p < 0.001). Incidence of intraventricular hemorrhage were significantly decreased.

CONCLUSIONS

After changing antibiotic, ventilation, and nutrition protocols, Candida infections were almost completely eliminated. The incidence of LOS and multiple LOS episodes decreased. Early full enteral nutrition was achieved without adverse effects, and fewer episodes of food intolerance were observed. Candida elimination appears feasible when antibiotic stewardship is implemented in conjunction with other interventions in an NICU.

Perspectives on the Use of Echinocandins in the Neonatal Intensive Care Unit

The neonatal intensive care unit (NICU) population, especially low birth weight and critically ill neonates, is at risk of invasive Candida infections, which are associated with high mortality rates and unfavorable long-term outcomes. The timely initiation of an appropriate antifungal treatment has been demonstrated to enhance the prognosis. Factors that should be considered in the choice of an antifungal agent include the causative Candida strain, the presence and location of deep tissue infection, any previous use of antifungal prophylaxis, and the presence of implanted devices. Amphotericin B and fluconazole, the first-line drugs for neonatal candidiasis, are not always suitable due to several limitations in terms of efficacy and adverse effects. Therefore, alternative antifungals have been studied and used in neonates when conventional antifungals are ineffective or contraindicated. This narrative review aims to provide an overview of the current literature regarding the use of echinocandins in the neonatal population. The three echinocandins, micafungin, caspofungin, and anidulafungin, share characteristics that make them useful for the treatment of neonatal candidiasis, including activity against a wide range of Candida strains and Candida biofilms and a favorable safety profile.

A Combination of β-Aescin and Newly Synthesized Alkylamidobetaines as Modern Components Eradicating the Biofilms of Multidrug-Resistant Clinical Strains of Candida glabrata

The current trend in microbiological research aimed at limiting the development of biofilms of multidrug-resistant microorganisms is increasingly towards the search for possible synergistic effects between various compounds. This work presents a combination of a naturally occurring compound, β-aescin, newly synthesized alkylamidobetaines (AABs) with a general structure-CnTMDAB, and antifungal drugs. The research we conducted consists of several stages. The first stage concerns determining biological activity (antifungal) against selected multidrug-resistant strains of Candida glabrata (C. glabrata) with the highest ability to form biofilms. The second stage of this study determined the activity of β-aescin combinations with antifungal compounds and alkylamidobetaines. In the next stage of this study, the ability to eradicate a biofilm on the polystyrene surface of the combination of β-aescin with alkylamidobetaines was examined. It has been shown that the combination of β-aescin and alkylamidobetaine can firmly remove biofilms and reduce their viability. The last stage of this research was to determine the safety regarding the cytotoxicity of both β-aescin and alkylamidobetaines. Previous studies on the fibroblast cell line have shown that C9 alkylamidobetaine can be safely used as a component of anti-biofilm compounds. This research increases the level of knowledge about the practical possibilities of using anti-biofilm compounds in combined therapies against C. glabrata.

Effect of Escin Alone or in Combination with Antifungal Agents on Resistant Candida glabrata Biofilms: Mechanisms of Action

Nowadays, the increase in antimicrobial-resistant fungi (AMR) is certainly a major health concern, and the development of alternative therapeutic strategies has become crucial. Natural products have been used to treat various infections, and their chemical properties contribute to the performance of their biological activities, such as antifungal action. The various virulence factors and mechanisms of resistance to antifungals contribute to making Candida glabrata one of the most frequent agents of candidiasis. Here we investigate the in vitro and in vivo activity of β-escin against Candida glabrata. The β-escin MICs were determined for a reference strain and two clinical isolates of C. glabrata. Furthermore, growth kinetics assays and biofilm inhibition/eradication assays (crystal violet) were performed. The differences in the expression of some anti-biofilm-associated genes were analyzed during biofilm inhibition treatment so that reactive oxygen species could be detected. The efficacy of β-escin was evaluated in combination with fluconazole, ketoconazole, and itraconazole. In addition, a Galleria mellonella infection model was used for in vivo treatment assays. Results have shown that β-escin had no toxicity in vitro or in vivo and was able to inhibit or destroy biofilm formation by downregulating some important genes, inducing ROS activity and affecting the membrane integrity of C. glabrata cells. Furthermore, our study suggests that the combination with azoles can have synergistic effects against C. glabrata biofilm. In summary, the discovery of new antifungal drugs against these resistant fungi is crucial and could potentially lead to the development of future treatment strategies.