Epidemiology, risk factors for and outcome of candidaemia among non-neutropenic patients in a Greek intensive care unit

Epidemiology of Candidemia and Fluconazole Resistance in an ICU before and during the COVID-19 Pandemic Era

The objectives of this study were to investigate the incidence of candidemia, as well as the factors associated with Candida species distribution and fluconazole resistance, among patients admitted to the intensive care unit (ICU) during the COVID-19 pandemic, as compared to two pre-pandemic periods. All patients admitted to the ICU due to COVID-19 from March 2020 to October 2021, as well as during two pre-pandemic periods (2005–2008 and 2012–2015), who developed candidemia, were included. During the COVID-19 study period, the incidence of candidemia was 10.2%, significantly higher compared with 3.2% and 4.2% in the two pre-pandemic periods, respectively. The proportion of non-albicans Candida species increased (from 60.6% to 62.3% and 75.8%, respectively), with a predominance of C. parapsilosis. A marked increase in fluconazole resistance (from 31% to 37.7% and 48.4%, respectively) was also observed. Regarding the total patient population with candidemia (n = 205), fluconazole resistance was independently associated with ICU length of stay (LOS) before candidemia (OR 1.03; CI: 1.01–1.06, p = 0.003), whereas the presence of shock at candidemia onset was associated with C. albicans (OR 6.89; CI: 2.2–25, p = 0.001), and with fluconazole-susceptible species (OR 0.23; CI: 0.07–0.64, p = 0.006). In conclusion, substantial increases in the incidence of candidemia, in non-albicansCandida species, and in fluconazole resistance were found in patients admitted to the ICU due to COVID-19, compared to pre-pandemic periods. At candidemia onset, prolonged ICU LOS was associated with fluconazole-resistant and the presence of shock with fluconazole-susceptible species.

Risk factors for invasive candida infection in critically ill patients - a systematic review and meta-analysis

Background

Current guidelines recommend empirical antifungal therapy in patients with sepsis with high risk of invasive Candida infection. However, many different risk factors have been derived from multiple studies. These risk factors lack specificity, and broad application would render most ICU patients eligible for empirical antifungal therapy.

Research Question

What risk factors for invasive Candida infection can be identified by a systematic review and meta-analysis?

Study Design and Methods

We searched PubMed, Web of Science, ScienceDirect, Biomed Central, and Cochrane and extracted the raw and adjusted OR for each risk factor associated with invasive Candida infection. We calculated pooled ORs for risk factors present in more than one study.

Results

We included 34 studies in our meta-analysis resulting in the assessment of 29 possible risk factors. Risk factors for invasive Candida infection included demographic factors, comorbid conditions, and medical interventions. Although demographic factors do not play a role for the development of invasive Candida infection, comorbid conditions (eg, HIV, Candida colonization) and medical interventions have a significant impact. The risk factors associated with the highest risk for invasive Candida infection were broad-spectrum antibiotics (OR, 5.6; 95% CI, 3.6-8.8), blood transfusion (OR, 4.9; 95% CI, 1.5-16.3), Candida colonization (OR, 4.7; 95% CI, 1.6-14.3), central venous catheter (OR, 4.7; 95% CI, 2.7-8.1), and total parenteral nutrition (OR, 4.6; 95% CI, 3.3-6.3). However, dependence between the various risk factors is probably high.

Interpretation

Our systematic review and meta-analysis identified patient- and treatment-related factors that were associated with the risk for the development of invasive Candida infection in the ICU. Most of the factors identified were either related to medical interventions during intensive care or to comorbid conditions.

Albumin Neutralizes Hydrophobic Toxins and Modulates Candida albicans Pathogenicity

Albumin is abundant in serum but is also excreted at mucosal surfaces and enters tissues when inflammation increases vascular permeability. Host-associated opportunistic pathogens encounter albumin during commensalism and when causing infections. Considering the ubiquitous presence of albumin, we investigated its role in the pathogenesis of infections with the model human fungal pathogen, Candida albicans. Albumin was introduced in various in vitro models that mimic different stages of systemic or mucosal candidiasis, where it reduced the ability of C. albicans to damage host cells. The amphipathic toxin candidalysin mediates necrotic host cell damage induced by C. albicans. Using cellular and biophysical assays, we determined that albumin functions by neutralizing candidalysin through hydrophobic interactions. We discovered that albumin, similarly, can neutralize a variety of fungal (α-amanitin), bacterial (streptolysin O and staurosporin), and insect (melittin) hydrophobic toxins. These data suggest albumin as a defense mechanism against toxins, which can play a role in the pathogenesis of microbial infections. IMPORTANCE Albumin is the most abundant serum protein in humans. During inflammation, serum albumin levels decrease drastically, and low albumin levels are associated with poor patient outcome. Thus, albumin may have specific functions during infection. Here, we describe the ability of albumin to neutralize hydrophobic microbial toxins. We show that albumin can protect against damage induced by the pathogenic yeast C. albicans by neutralizing its cytolytic toxin candidalysin. These findings suggest that albumin is a toxin-neutralizing protein that may play a role during infections with toxin-producing microorganisms.

Deciphering the epidemiology of invasive candidiasis in the intensive care unit: is it possible?

Invasive candidiasis (IC) has emerged in the last decades as an important cause of morbidity, mortality, and economic load in the intensive care unit (ICU). The epidemiology of IC is still a difficult and unsolved enigma for the literature. Accurate estimation of the true burden of IC is difficult due to variation in definitions and limitations inherent to available case-finding methodologies. Candidemia and intra-abdominal candidiasis (IAC) are the two predominant types of IC in ICU. During the last two decades, an increase in the incidence of candidemia has been constantly reported particularly in the expanding populations of elderly or immunosuppressed patents, with a parallel change in Candida species (spp.) distribution worldwide. Epidemiological shift in non-albicans spp. has reached worrisome trends. Recently, a novel, multidrug-resistant Candida spp., Candida auris, has globally emerged as a nosocomial pathogen causing a broad range of healthcare-associated invasive infections. Epidemiological profile of IAC remains imprecise. Though antifungal drugs are available for Candida infections, mortality rates continue to be high, estimated to be up to 50%. Increased use of fluconazole and echinocandins has been associated with the emergence of resistance to these drugs, which affects particularly C. albicans and C. glabrata. Crucial priorities for clinicians are to recognize the epidemiological trends of IC as well as the emergence of resistance to antifungal agents to improve diagnostic techniques and strategies, develop international surveillance networks and antifungal stewardship programmes for a better epidemiological control of IC.

The transcription factor Ndt80 is a repressor of Candida parapsilosis virulence attributes

Candida parapsilosis is an emergent opportunistic yeast among hospital settings that affects mainly neonates and immunocompromised patients. Its most remarkable virulence traits are the ability to adhere to prosthetic materials, as well as the formation of biofilm on abiotic surfaces. The Ndt80 transcription factor was identified as one of the regulators of biofilm formation by C. parapsilosis; however, its function in this process was not yet clarified. By knocking out NDT80 (CPAR2-213640) gene, or even just one single copy of the gene, we observed substantial alterations of virulence attributes, including morphogenetic changes, adhesion and biofilm growth profiles. Both ndt80Δ and ndt80ΔΔ mutants changed colony and cell morphologies from smooth, yeast-shaped to crepe and pseudohyphal elongated forms, exhibiting promoted adherence to polystyrene microspheres and notably, forming a higher amount of biofilm compared to wild-type strain. Interestingly, we identified transcription factors Ume6, Cph2, Cwh41, Ace2, Bcr1, protein kinase Mkc1 and adhesin Als7 to be under Ndt80 negative regulation, partially explaining the phenotypes displayed by the ndt80ΔΔ mutant. Furthermore, ndt80ΔΔ pseudohyphae adhered more rapidly and were more resistant to murine macrophage attack, becoming deleterious to such cells after phagocytosis. Unexpectedly, our findings provide the first evidence for a direct role of Ndt80 as a repressor of C. parapsilosis virulence attributes. This finding shows that C. parapsilosis Ndt80 functionally diverges from its homolog in the close related fungal pathogen C. albicans.

Risk of invasive candidiasis with prolonged duration of ICU stay: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the duration of intensive care unit (ICU) stay prior to onset of invasive candidiasis (IC)/candidaemia.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Cochrane, Embase and Web of Science databases were searched through June 2019 to identify relevant studies.

ELIGIBILITY CRITERIA

Adult patients who had been admitted to the ICU and developed an IC infection.

DATA EXTRACTION AND SYNTHESIS

The following data were extracted from each article: length of hospital stay, length of ICU stay, duration of ICU admission prior to candidaemia onset, percentage of patients who received antibiotics and duration of their antibiotic therapy prior to candidaemia onset, and overall mortality. In addition to the traditional meta-analyses, meta-regression was performed to explore possible mediators which might have contributed to the heterogeneity.

RESULTS

The mean age of patients ranged from 28 to 76 years across selected studies. The pooled mean duration of ICU admission before onset of candidaemia was 12.9 days (95% CI 11.7 to 14.2). The pooled mean duration of hospital stay was 36.3±5.3 days (95% CI 25.8 to 46.7), and the pooled mean mortality rate was 49.3%±2.2% (95% CI 45.0% to 53.5%). There was no significant difference in duration of hospital stay (p=0.528) or overall mortality (p=0.111), but a significant difference was observed in the mean length of ICU stay (2.8 days, p<0.001), between patients with and without Candida albicans. Meta-regression analysis found that South American patients had longer duration of ICU admission prior to candidaemia onset than patients elsewhere, while those in Asia had the shortest duration.

CONCLUSIONS

Patients with IC are associated with longer ICU stay, with the shortest duration of ICU admission prior to the candidaemia onset in Asia. This shows a more proactive strategy in the diagnosis of IC should be considered in caring for ICU patients.

Epidemiological Trends of Fungemia in Greece with a Focus on Candidemia during the Recent Financial Crisis: a 10-Year Survey in a Tertiary Care Academic Hospital and Review of Literature

Updated information on the epidemiology of candidemia, particularly during severe socioeconomic events, is important for proper management of these infections. A systematic literature review on candidemia in Greece and a retrospective surveillance study were conducted in a tertiary university hospital during the years of the recent financial crisis (2009 to 2018) in order to assess changes in incidence rates, patient characteristics, species distribution, antifungal susceptibilities, and drug consumption. The average annual incidence of 429 candidemic episodes was 2.03/10,000 bed days, with 9.88 in adult intensive care units (ICUs), 1.74 in surgical wards, and 1.81 in internal medicine wards, where a significant increase was observed (1.15, 1.85, and 2.23/10,000 bed days in 2009 to 2011, 2012 to 2014, and 2015 to 2018, respectively; P = 0.004). Candida albicans was the most common species (41%), followed by Candida parapsilosis species complex [SC] (37%), Candida glabrata SC (11%), Candida tropicalis (7%), Candida krusei (1%), and other rare Candida spp. (3%). Mixed infections were found in 20/429 (4.7%) cases, while 33 (7%) cases were due to non-Candida spp. Overall, 44/311 (14%) isolates were resistant/non-wild type (WT) to the nine antifungals tested, with 23/113 (20%) C. parapsilosis SC and 2/34 (6%) C. glabrata SC isolates being resistant to fluconazole (1 panechinocandin and 2 panazole resistant). All isolates were susceptible/WT to amphotericin B and flucytosine. While the overall consumption of antifungals diminished (P = 0.02), with a mean of 17.93 defined daily doses (DDD)/100 bed days, increased micafungin use was correlated with the rise in C. parapsilosis SC (P = 0.04). A significant increase of candidemia in internal medicine wards and of C. parapsilosis SC infections was found during the years of financial crisis. Although resistance rates remain low (<14%), fluconazole-resistant C. parapsilosis SC and multidrug-resistant C. glabrata SC isolates are of major concern.

An estimate of the burden of serious fungal diseases in Greece

Data on the epidemiology of serious fungal infections in Greece are scarce. Our aim was to calculate the burden of serious fungal diseases in Greece. A thorough literature search for papers reporting epidemiological data on serious fungal diseases in Greece was performed. Where no Greek data existed, we used a structured set of assumptions to estimate fungal disease burden, based on specific high-risk populations. Of the 10.8 million population, 85.5 % are adults and 27 % are over 60 years of age. The annual fungal disease estimates are as follows: 142,337 Greek women get recurrent vaginal thrush (2,632 cases/100,000 females); there are 889 cases of esophageal candidiasis (8.2 cases/100,000); annual incidence of Pneumocystis pneumonia is 112 cases; chronic pulmonary aspergillosis prevalence is 386 cases; there are 20,843 patients with allergic bronchopulmonary aspergillosis and 27,744 with severe asthma with fungal sensitization; candidaemia incidence is 541 cases (5.0/100,000); there are 81 cases of Candida peritonitis; invasive aspergillosis occurs in 1,125 patients. According to our calculations, 194,067 individuals (1.79 cases/100,000) in Greece suffer from serious fungal diseases each year. This is the first attempt to determine the burden of fungal diseases in Greece, and provides a crude estimate on its impact on public health.

Characteristics and risk factors for 28-day mortality of hospital acquired fungemias in ICUs: data from the EUROBACT study

BACKGROUND

To characterize and identify prognostic factors for 28-day mortality among patients with hospital-acquired fungemia (HAF) in the Intensive Care Unit (ICU).

METHODS

A sub-analysis of a prospective, multicenter non-representative cohort study conducted in 162 ICUs in 24 countries.

RESULTS

Of the 1156 patients with hospital-acquired bloodstream infections (HA-BSI) included in the EUROBACT study, 96 patients had a HAF. Median time to its diagnosis was 20 days (IQR 10.5-30.5) and 9 days (IQR 3-15.5) after hospital and ICU admission, respectively. Median time to positivity of blood culture was longer in fungemia than in bacteremia (48.7 h vs. 38.1 h; p = 0.0004). Candida albicans was the most frequent fungus isolated (57.1%), followed by Candida glabrata (15.3%) and Candida parapsilosis (10.2%). No clear source of HAF was detected in 33.3% of the episodes and it was catheter-related in 21.9% of them. Compared to patients with bacteremia, HAF patients had a higher rate of septic shock (39.6% vs. 21.6%; p = 0.0003) and renal dysfunction (25% vs. 12.4%; p = 0.0023) on admission and a higher rate of renal failure (26% vs. 16.2%; p = 0.0273) at diagnosis. Adequate treatment started within 24 h after blood culture collection was less frequent in HAF patients (22.9% vs. 55.3%; p < 0.001). The 28-day all cause fatality was 40.6%. According to multivariate analysis, only liver failure (OR 14.35; 95% CI 1.17-175.6; p = 0.037), need for mechanical ventilation (OR 8.86; 95% CI 1.2-65.24; p = 0.032) and ICU admission for medical reason (OR 3.87; 95% CI 1.25-11.99; p = 0.020) were independent predictors of 28-day mortality in HAF patients.

CONCLUSIONS

Fungi are an important cause of hospital-acquired BSI in the ICU. Patients with HAF present more frequently with septic shock and renal dysfunction on ICU admission and have a higher rate of renal failure at diagnosis. HAF are associated with a significant 28-day mortality rate (40%), but delayed adequate antifungal therapy was not an independent risk factor for death. Liver failure, need for mechanical ventilation and ICU admission for medical reason were the only independent predictors of 28-day mortality.

Antifungal drug resistance among Candida species: mechanisms and clinical impact

The epidemiology of Candida infections has changed in recent years. Although Candida albicans is still the main cause of invasive candidiasis in most clinical settings, a substantial proportion of patients is now infected with non-albicans Candida species. The various Candida species vary in their susceptibility to the most commonly used antifungal agents, and the intrinsic resistance to antifungal therapy seen in some species, along with the development of acquired resistance during treatment in others, is becoming a major problem in the management of Candida infection. A better understanding of the mechanisms and clinical impact of antifungal drug resistance is essential for the efficient treatment of patients with Candida infection and for improving treatment outcomes. Herein, we report resistance to the azoles and echinocandins among Candida species.

Epidemiology of invasive candidiasis in a surgical intensive care unit: an observational study

BACKGROUND

Invasive candidiasis (IC) is a frequent and life-threatening infection in critically ill patients. The aim of this study was to evaluate the epidemiology of IC and the antifungal susceptibility of etiological agents in patients admitted to our surgical intensive care unit (SICU) in Spain.

METHODS

We designed a prospective, observational, single center, population-based study in a SICU. We included all consecutive adult patients (≥18 years old) who had documented IC, either on admission or during their stay, between January 2012 and December 2013.

RESULTS

There were a total of 22 episodes of IC in the 1149 patients admitted during the 24-month study. The overall IC incidence was 19.1 cases per 1000 admissions. Thirteen cases of IC (59.1%) were intra-abdominal candidiasis (IAC) and 9 (40.9%) were candidemias. All cases of IAC were patients with secondary peritonitis and severe sepsis or septic shock. The overall crude mortality rate was 13.6%; while, it was 33% in patients with candidemia. All patients with IAC survived, including one patient with concomitant candidemia. The most common species causing IC was Candida albicans (13; 59.1%) followed by Candida parapsilosis (5; 22.7%), and Candida glabrata (2; 9.1%). There was also one case each (4.5%) of Candida krusei and Candida tropicalis. Thus, the ratio of non-C. albicans (9) to C. albicans (13) was 1:1.4. There was resistance to fluconazole and itraconazole in 13.6% of cases. Resistance to other antifungals was uncommon.

CONCLUSIONS

Candida parapsilosis was the second most common species after C. albicans, indicating the high prevalence of non-C. albicans species in the SICU. Resistance to azoles, particularly fluconazole, should be considered when starting an empirical treatment. Although IAC is a very frequent form of IC in critically ill surgical patients, prompt antifungal therapy and adequate source control appears to lead to a good outcome. However, our results are closely related to our ICU and any generalization must be taken with caution. Therefore, further investigations are needed.

Association of KPC-producing Klebsiella pneumoniae colonization or infection with Candida isolation and selection of non-albicans species

Clinical specimens from 565 patients hospitalized in 2 intensive care units (ICUs A and B) during a 28-month period were cultured on appropriate media for isolation of Candida. Forty-nine (9%) patients had at least a Candida spp.-positive sample. Candida albicans was the predominant species isolated from 26 (53%) patients. Seventeen patients (3%) developed candidemia. Multivariate analysis showed that obesity, female gender, hospitalization during summer months, admission at ICU B, parenteral nutrition, administration of metronidazole, transplantation, and KPC-producing Klebsiella pneumoniae (KPC-Kp) infection were independently associated with Candida spp. isolation. Candidemia was associated with cortisone administration, KPC-Kp infection, and presence of colostomy or abdominal catheter. Administration of fluconazole was a protective factor for both Candida spp. isolation and infection, leading to selection of Candida non-albicans species. Among several risk factors, KPC-Kp infection and colonization are identified as statistically significant factors associated with Candida isolation, especially of non-albicans species.

Factors predicting prolonged empirical antifungal treatment in critically ill patients

Objective

To determine the incidence, risk factors, and impact on outcome of prolonged empirical antifungal treatment in ICU patients.

Methods

Retrospective observational study performed during a one-year period. Patients who stayed in the ICU >48 h, and received empirical antifungal treatment were included. Patients with confirmed invasive fungal disease were excluded. Prolonged antifungal treatment was defined as percentage of days in the ICU with antifungals > median percentage in the whole cohort of patients.

Results

Among the 560 patients hospitalized for >48 h, 153 (27%) patients received empirical antifungal treatment and were included in this study. Fluconazole was the most frequently used antifungal (46% of study patients). Median length of ICU stay was 19 days (IQR 8, 34), median duration of antifungal treatment was 8 days (IQR 3, 16), and median percentage of days in the ICU with antifungals was 48% (IQR 25, 80). Seventy-seven patients (50%) received prolonged empirical antifungal treatment. Chemotherapy (OR [95% CI] 2.6 [1.07-6.69], p = 0.034), and suspected infection at ICU admission (3.1 [1.05-9.48], p = 0.041) were independently associated with prolonged empirical antifungal treatment.

Duration of mechanical ventilation and ICU stay were significantly shorter in patients with prolonged empirical antifungal treatment compared with those with no prolonged empirical antifungal treatment. However, ICU mortality was similar in the two groups (46 versus 52%, p = 0.62).

Conclusion

Empirical antifungal treatment was prescribed in a large proportion of study patients. Chemotherapy, and suspicion of infection at ICU admission are independently associated with prolonged empirical antifungal treatment.

Epidemiology of invasive fungal infections in the intensive care unit: results of a multicenter Italian survey (AURORA Project)

Purpose

The aims of this study are to evaluate the epidemiology of invasive fungal infections (IFIs) in patients admitted to an intensive care unit (ICU) in Southern Italy and the in vitro antifungal susceptibility of isolates.

Methods

A surveillance program was implemented in 18 ICUs. IFI cases were recorded using a standardized form.

Results

A total of 105 episodes of IFIs occurred in 5,561 patients during the 18-month study. The main infections were caused by yeasts, more than filamentous fungi (overall incidence of 16.5 cases per 1,000 admissions and 2.3 cases per 1,000 admissions, respectively). The overall crude mortality rate was high (42.8 %), particularly for mold infections (61.5 %). All yeast infections were Candida bloodstream infections. Over half (59.8 %) were caused by Candida non-albicans, with C. parapsilosis being the most common (61.8 %). In the multivariate model, trauma admission diagnosis, prolonged stay in the ICU, and parenteral nutrition were independently associated with candidemia due to C. parapsilosis [odds ratio (OR) 3.5, (1.8–5.2); OR 3.5, (1.02–3.5); OR 3.6, (1.28–6.99), respectively]. Among mold infections, 12 patients suffered from invasive pulmonary aspergillosis, with Aspergillus fumigatus as the predominant pathogen (41.7 %). One case of brain scedosporiosis was identified. Overall, azoles and echinocandins resistance was uncommon.

Conclusions

Candida non-albicans species are the most frequent cause of candidemia in ICU patients. Mold infections are associated with a high mortality rate. This study confirms the importance of the epidemiological surveillance on IFIs in the ICU setting for documenting species distribution and antimicrobial susceptibility patterns to guide therapeutic choices.

Epidemiological and clinical characteristics of nosocomial candidiasis in university hospitals in Cuiabá--Mato Grosso, Brazil

BACKGROUND

Fungal infections are emerging as an important cause of human disease, especially among hospitalized patients with serious underlying disease and several risk factors.

AIMS

To evaluate epidemiological and clinical characteristics of patients with nosocomial candidiasis in university hospitals in Cuiabá - MT, Brazil.

METHODS

A descriptive study of 91 patients admitted to university hospitals in Cuiabá - MT, with clinical and laboratory diagnosis of nosocomial candidiasis, over a 20-month period.

RESULTS

A rate for nosocomial infections by Candida spp. of 5 per 1000 admissions, proportional mortality of 14.4% and lethality of 53.8% were determined. The patient age ranged from 29 days to 82 years-old, among which, 74.7% were adults and 25.3% children. The intensive care units contributed with the highest number of cases of infection by Candida spp. (69.2%). The most important underlying disease was gastrointestinal tract disease (11%). Prematurity and low birth weight were the most important risk factors among newborns. The use of antibiotics, invasive procedures, H(2) blockers, multiple blood transfusions and stay length of ≥21 days were the most frequent risk factors among adults. Candida albicans was the most common species in all cases.

CONCLUSIONS

In this study, C. albicans was the most frequently detected species in candidiasis and risk factors increased the susceptibility of hospitalized patients to acquiring a nosocomial infection by Candida spp.