Distribution, trends, and antifungal susceptibility of Candida species causing candidemia in Japan, 2010-2019: A retrospective observational study based on national surveillance data

The first prevalence and antifungal susceptibility profile of Candida infections in Palestine, 2022

BACKGROUND

Candida spp. are the most common cause of opportunistic fungal infections and are associated with a high mortality rate worldwide. In Palestine, the prevalence of Candida spp. infections remains elusive.

METHODS

We performed our study at two hospitals in Palestine (Istishari Arab Hospital, and Najah National University Hospital). All patients diagnosed with candidiasis during the year 2022 have participated in the study. The prevalence of Candida spp., their distribution, and the activity of selected antifungals against Candida pathogens were assessed. In combination with phenotypic properties, Candida isolates were identified and tested for antifungal susceptibility using the colorimetric VITEK-2 Compact system.

RESULTS

Our results showed that the prevalence of Candida spp. among infected samples was 11.6%. A total of eleven different Candida spp. were identified. Among these isolates, C. albicans (46.54%) was the most frequent, followed by C. glabrata (16.14%), C. tropicalis (13.83%), C. parapsilosis (4.82%), C. krusei (3.56%), C. dubliniensis (2.09%), C. ciferrii (1.67%), C. lusitaniae (0.83%), C. guilliermondii (0.62%), C. kefyer (0.41%) and C. spherica (0.20%). Among C. albicans, all isolates were 100% susceptible to fluconazole and micafungin. The susceptibility rates to Amphotericin B and flucytosine were 95% and 99%, respectively. The susceptibility rates of non-albicans Candida spp. (NAC) to fluconazole, voriconazole, amphotericine B, caspofungin, flucytosine and micafungin were 70%, 99%, 97%, ,72%, 92% and 100%, respectively. The incidence of Candida infections was higher in the intensive care unit and surgery department as compared to other hospital departments.

CONCLUSIONS

Four pathogens are responsible for the most invasive infections: C. albicans, C. glabrata, C. tropicalis, and C. parapsilosis. A notable characteristic of this study was the high frequency of NAC species which were often more resistant to antifungal agents. A quick and accurate system like Vitek 2 compact was suggested for the careful species identification of clinical isolates of Candida. We suggest that continued surveillance of species distribution and susceptibility to antifungals will enhance future burden estimates and assist in evaluating preventative measures' effectiveness.

Epidemiology of Invasive Candidiasis

Invasive candidiasis (IC) is an increasingly prevalent, costly, and potentially fatal infection brought on by the opportunistic yeast, Candida. Previously, IC has predominantly been caused by C. albicans which is often drug susceptible. There has been a global trend towards decreasing rates of infection secondary to C. albicans and a rise in non-albicans species with a corresponding increase in drug resistance creating treatment challenges. With advances in management of malignancies, there has also been an increase in the population at risk from IC along with a corresponding increase in incidence of breakthrough IC infections. Additionally, the emergence of C. auris creates many challenges in management and prevention due to drug resistance and the organism's ability to transmit rapidly in the healthcare setting. While the development of novel antifungals is encouraging for future management, understanding the changing epidemiology of IC is a vital step in future management and prevention.

Systematic Review of Candidemia in Brazil: Unlocking Historical Trends and Challenges in Conducting Surveys in Middle-Income Countries

INTRODUCTION

Candidemia, a bloodstream infection predominantly affecting critically ill patients, poses a significant global health threat especially with the emergence of non-albicans Candida species, including drug-resistant strains. In Brazil, limited access to advanced diagnostic tools and trained microbiologists hampers accurate identification of Candida species and susceptibility to antifungals testing hindering surveillance efforts.

METHODS

We conducted a systematic review spanning publications from 2017 to 2023 addressing Candida species distribution and antifungal susceptibility among Brazilian patients with candidemia.

RESULTS

Despite initially identifying 7075 records, only 16 met inclusion criteria providing accurate information of 2305 episodes of candidemia. The predominant species were C. albicans, C. parapsilosis, and C. tropicalis, followed by notable proportions of Nakaseomyces glabratus. Limited access to diagnostic tests was evident as only 5 out of 16 studies on candidemia were able to report antifungal susceptibility testing results. In vitro resistance to echinocandins was rare (only 6/396 isolates, 1,5%). In counterpart, fluconazole exhibited resistance rates ranging from 0 to 43%, with great heterogeneity among different studies and species of Candida considered.

CONCLUSION

Our review underscores the critical need for enhanced surveillance and research efforts to address the evolving landscape of candidemia and antifungal resistance in Brazil. Despite some limitations, available data suggest that while resistance to echinocandins and amphotericin B remains rare, there is a growing concern regarding resistance to fluconazole among Candida species.

Temporal trends in antifungal susceptibility of Cryptococcus neoformans isolates from a reference laboratory in the United States, 2011-2021

BACKGROUND

There are no established clinical breakpoints for antifungal agents against Cryptococcus species; however, epidemiological cut-off values can help distinguish wild-type (WT) isolates without any acquired resistance from non-WT strains, which may harbour resistance mechanisms.

PATIENTS/METHODS

We describe the trends of antifungal MICs and percentages of WT C. neoformans species complex (CNSC) isolates processed in our reference laboratory from November 2011 to June 2021. There were only nine isolates in 2011, thus, we included them in the year 2012 for data analysis. Clinical data is also described when available.

RESULTS

We identified 632 CNSC, the majority collected from blood (n = 301), cerebrospinal fluid (n = 230), and respiratory (n = 71) sources. The overall percentage of WT isolates for amphotericin B (AMB), 5-flucytosine, and fluconazole was 77%, 98%, and 91%, respectively. We noticed a statistically significant change in the percentage of AMB WT isolates over the years, with 98% of isolates being WT in 2012 compared to 79% in 2021 (p < .01). A similar change was not observed for other antifungal agents. Clinical data was available for 36 patients, primarily non-HIV immunocompromised patients with disseminated cryptococcosis. There were no statistically significant differences in the clinical characteristics and outcomes between patients with WT (58.3%) versus non-WT (41.7%) isolates, but we noticed higher mortality in patients infected with an AMB non-WT CNSC isolate.

CONCLUSIONS

We observed an increase in the percentage of AMB non-WT CNSC isolates in the past decade. The clinical implications of this finding warrant further evaluation in larger studies.

Candida parapsilosis complex in the clinical setting

Representatives of the Candida parapsilosis complex are important yeast species causing human infections, including candidaemia as one of the leading diseases. This complex comprises C. parapsilosis, Candida orthopsilosis and Candida metapsilosis, and causes a wide range of clinical presentations from colonization to superficial and disseminated infections with a high prevalence in preterm-born infants and the potential to cause outbreaks in hospital settings. Compared with other Candida species, the C. parapsilosis complex shows high minimal inhibitory concentrations for echinocandin drugs due to a naturally occurring FKS1 polymorphism. The emergence of clonal outbreaks of strains with resistance to commonly used antifungals, such as fluconazole, is causing concern. In this Review, we present the latest medical data covering epidemiology, diagnosis, resistance and current treatment approaches for the C. parapsilosis complex. We describe its main clinical manifestations in adults and children and highlight new treatment options. We compare the three sister species, examining key elements of microbiology and clinical characteristics, including the population at risk, disease manifestation and colonization status. Finally, we provide a comprehensive resource for clinicians and researchers focusing on Candida species infections and the C. parapsilosis complex, aiming to bridge the emerging translational knowledge and future therapeutic challenges associated with this human pathogen.

Study of Candidemia and its Antifungal Susceptibility Profile at the University Hospital of Montevideo, Uruguay

Systemic candidiasis are high mortality infections caused by yeasts of the genus Candida, affecting patients with numerous risk factors. Nowadays, candidemia produced by "non-albicans" species has increased considerably. Timely diagnosis and subsequent treatment substantially improve patients' survival. Our objectives are to study the frequency, distribution, and antifungal susceptibility profiles of candidemia isolates in our hospital. We conducted a descriptive, cross-sectional study. Positive blood cultures were recorded from January 2018 to December 2021. Positive Candida genus blood cultures were selected, classified, and analyzed on their susceptibility profile for amphotericin B, fluconazole and caspofungin using AST-YS08® card for VITEK 2 Compact® to determine minimum inhibitory concentration (MIC) and CLSI M60 2020 2nd Edition to determine breakpoints. 3862 positive blood cultures were obtained, 113 (2.93%) presented growth of Candida spp., corresponding to 58 patients. 55.2% came from the Hospitalization Ward and Emergency Services and 44.8% from the Intensive Care Unit. The species were distributed as follows: Nakaseomyces glabratus (Candida glabrata) (32.74%), Candida albicans (27.43%), Candida parapsilosis (23.01%), Candida tropicalis (7.08%) and others (9.73%). Most species were found to be susceptible to most antifungals, except for C. parapsilosis, presenting 4 isolates with resistance to fluconazole and N. glabratus (C. glabrata), whose clinical susceptibility data remains insufficient to provide accurate breakpoints. The percentage of recorded positive blood cultures of Candida spp. was 2.93%, these results were consistent with those reported at a regional level. A predominance of "non-albicans" species was observed. It is essential to know the prevalence, epidemiology, and susceptibility profiles of candidemia in our country, as well as being updated on its subsequent changes, maintaining epidemiological surveillance. This allows professionals to map out early and effective therapeutic strategies, staying alert of possible multi-resistant strains.

The Epidemiology and Clinical Characteristics of Fungemia in a Tertiary Hospital in Southern China: A 6-Year Retrospective Study

Knowledge of the epidemiology and clinical characteristics of fungemia in southern China is limited. We conducted a six-year retrospective descriptive study to analyze the epidemiological and clinical characteristics of fungemia at the largest tertiary hospital in Guangxi, southern China. Data were obtained from the laboratory registry of patients with fungemia between January 2014 and December 2019. Demographic characteristics, underlying medical conditions, and outcomes for each case were analyzed. A total of 455 patients with fungemia were identified. Unexpectedly, Talaromyces marneffei (T. marneffei) was the most frequently isolated agent causing fungemia in the region (149/475, 31.4%), and Candida albicans (C. albicans) was the most commonly isolated Candida spp. (100/475, 21.1%). We identified that more than 70% of talaromycosis fungemia developed in AIDS patients, whereas candidemia was most commonly associated with a history of recent surgery. Notably, the total mortality rate of fungemia and the mortality rate in patients with T. marneffei and Cryptococcus neoformans (C. neoformans) fungemia were significantly higher in HIV-uninfected patients than in HIV-infected patients. In conclusion, the clinical pattern of fungemia in Guangxi is different from that in previous studies. Our study may provide new guidance for the early diagnosis and prompt treatment of fungemia in similar geographic regions.

Candidiasis: From cutaneous to systemic, new perspectives of potential targets and therapeutic strategies

Candidiasis is an infection caused by fungi from a Candida species, most commonly Candida albicans. C. albicans is an opportunistic fungal pathogen typically residing on human skin and mucous membranes of the mouth, intestines or vagina. It can cause a wide variety of mucocutaneous barrier and systemic infections; and becomes a severe health problem in HIV/AIDS patients and in individuals who are immunocompromised following chemotherapy, treatment with immunosuppressive agents or after antibiotic-induced dysbiosis. However, the immune mechanism of host resistance to C. albicans infection is not fully understood, there are a limited number of therapeutic antifungal drugs for candidiasis, and these have disadvantages that limit their clinical application. Therefore, it is urgent to uncover the immune mechanisms of the host protecting against candidiasis and to develop new antifungal strategies. This review synthesizes current knowledge of host immune defense mechanisms from cutaneous candidiasis to invasive C. albicans infection and documents promising insights for treating candidiasis through inhibitors of potential antifungal target proteins.