Multicenter retrospective development and validation of a clinical prediction rule for nosocomial invasive candidiasis in the intensive care setting

Clinical and epidemiological aspects of Candida yeast infections and rational use of antifungals

Aim: The objective of this study was to evaluate the clinical and epidemiological aspects of Candida infections. Methods: The study relied on the analysis of electronic medical records. Results: Among 183 patients with positive fungal infections, 57 were from the community and 126 from hospitals. Females predominated in both groups (82.4% in the community, 54.7% in hospitals). Non-albicans Candida spp. accounted for 62.8% of cases. Antifungal therapy was prescribed for 67 patients, with a 55.6% mortality rate. Conclusion: The increasing prevalence of non-albicans Candida species highlights the need for better candidiasis monitoring and control, especially concerning antifungal use amidst rising antimicrobial resistance, particularly in empirical therapy scenarios.

Risk Factors for Invasive Candidiasis in Critically Ill Patients Who Underwent Emergency Gastrointestinal Surgery for Complicated Intra-Abdominal Infection

Background: Candida species account for approximately 15% of hospital-associated infections, causing fatal consequences, especially in critically ill patients. This study aimed to evaluate invasive candidiasis (IC) risk factors in critically ill patients undergoing surgery. Patients and Methods: We retrospectively reviewed the medical records of 583 patients who underwent emergency surgery for complicated intra-abdominal infections between January 2016 and December 2021. Patients were divided into two groups according to the presence or absence of IC during their hospital stay. IC was defined as culture-proven candidemia and intra-abdominal candidiasis. Results: This study included 373 patients for the final analysis, of whom 320 were discharged without IC (IC absent group) and 53 presented with IC (IC present group) during their hospital stay. The IC present group showed a higher in-hospital mortality rate (35.8 vs. 8.8%; p < 0.001), with 66.0% of the patients diagnosed within 10 days, whereas only 6.5% were diagnosed beyond 20 days after admission. Stomach (odds ratio [OR], 4.188; 95% confidence interval [CI], 1.204-14.561; p = 0.024) and duodenum (OR, 7.595; 95% CI, 1.934-29.832; p = 0.004) as infection origin, higher Acute Physiology and Chronic Health Evaluation II (APACHE II) score (OR, 1.097; 95% CI, 1.044-1.152; p < 0.001), and lower initial systolic blood pressure (OR, 0.983; 95% CI, 0.968-0.997; p = 0.018) were risk factors of IC after emergency gastrointestinal surgery. Conclusions: Patients who had stomach and duodenum as infection origin, higher APACHE II scores, and lower initial systolic blood pressure had a higher risk of developing IC during their hospital stay after emergency gastrointestinal surgery. Prophylactic antifungal agents can be carefully considered for critically ill patients with these features.

Invasive candidiasis

Invasive candidiasis is an important fungal disease caused by Candida albicans and, increasingly, non-albicans Candida pathogens. Invasive Candida infections originate most frequently from endogenous human reservoirs and are triggered by impaired host defences. Signs and symptoms of invasive candidiasis are non-specific; candidaemia is the most diagnosed manifestation, with disseminated candidiasis affecting single or multiple organs. Diagnosis poses many challenges, and conventional culture techniques are frequently supplemented by non-culture-based assays. The attributable mortality from candidaemia and disseminated infections is ~30%. Fluconazole resistance is a concern for Nakaseomyces glabratus, Candida parapsilosis, and Candida auris and less so in Candida tropicalis infection; acquired echinocandin resistance remains uncommon. The epidemiology of invasive candidiasis varies in different geographical areas and within various patient populations. Risk factors include intensive care unit stay, central venous catheter use, broad-spectrum antibiotics use, abdominal surgery and immune suppression. Early antifungal treatment and central venous catheter removal form the cornerstones to decrease mortality. The landscape of novel therapeutics is growing; however, the application of new drugs requires careful selection of eligible patients as the spectrum of activity is limited to a few fungal species. Unanswered questions and knowledge gaps define future research priorities and a personalized approach to diagnosis and treatment of invasive candidiasis is of paramount importance.

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.

Early diagnosis of candidemia with explainable machine learning on automatically extracted laboratory and microbiological data: results of the AUTO-CAND project

BACKGROUND

Candidemia is associated with a heavy burden of morbidity and mortality in hospitalized patients. The availability of blood culture results could require up to 48-72 h after blood draw; thus, early treatment decisions are made in the absence of a definite diagnosis.

METHODS

In this retrospective study, we assessed the performance of different supervised machine learning algorithms for the early differential diagnosis of candidemia and bacteremia in adult patients on a large dataset automatically extracted within the AUTO-CAND project.

RESULTS

Overall, 12,483 episodes of candidemia (1275; 10%) or bacteremia (11,208; 90%) were included in the analysis. A random forest classifier achieved the best diagnostic performance for candidemia, with sensitivity 0.98 and specificity 0.65 on the training set (true skill statistic [TSS] = 0.63) and sensitivity 0.74 and specificity 0.57 on the test set (TSS = 0.31). Then, the random classifier was trained in the subgroup of patients with available serum β-D-glucan (BDG) and procalcitonin (PCT) values by exploiting the feature ranking learned in the entire dataset. Although no statistically significant differences were observed from the performance measures obtained by employing BDG and PCT alone, the performance measures of the classifier that included the features selected in the entire dataset, plus BDG and PCT, were the highest in most cases.

CONCLUSIONS

Random forest classifiers trained on large datasets of automatically extracted data have the potential to improve current diagnostic algorithms for candidemia. However, further development through implementation of automatically extracted clinical features may be necessary to achieve crucial improvements.

The influence of continuous renal replacement therapy on 1,3-β-d-glucan levels in critically ill patients: a single-center retrospective propensity score study

1,3-β-d-Glucan (BDG) is commonly used for diagnosing invasive fungal infections (IFIs). While exposure to cellulose-based hemodialyzers is known to cause false-positive BDG results, the impact of modern hemofilters used in continuous renal replacement therapy (CRRT) remains unclear. This retrospective, single-center cohort study aimed to evaluate the effect of CRRT on BDG levels in critically ill patients. We included adult intensive care unit (ICU) patients with ≥1 BDG measurement between December 2019 and December 2020. The primary outcome was the rate of false-positive BDG results in patients exposed to CRRT compared to unexposed patients. Propensity score analysis was performed to control for confounding factors. A total of 103 ICU patients with ≥1 BDG level were identified. Most (72.8%) were medical ICU patients. Forty patients underwent CRRT using hemofilter membranes composed of sodium methallyl sulfonate copolymer (AN 69 HF) (82.5%) and of polyarylethersulfone (PAES) (17.5%). Among the 91 patients without proven IFI, 31 (34.1%) had false-positive BDG results. Univariable analysis showed an association between CRRT exposure and false-positive BDG results. However, the association between CRRT exposure and false-positive BDG results was no longer significant across three propensity score models employed: 1:1 match (n = 32) (odds ratio (OR) 1.65, p = .48), model-adjusted (n = 91) (OR 1.75, p = .38), quintile-adjusted (n = 91) (OR 1.78, p = .36). In this single-center retrospective analysis, exposure to synthetic CRRT membranes did not independently increase the risk of false-positive BDG results. Larger prospective studies are needed to further evaluate the association between CRRT exposure and false-positive BDG results in critically ill patients with suspected IFI.

Current Utilization of Antifungal Agents for Intra-abdominal Infections Categorized by Patient Risk Factors During Surgical Procedures: A Literature Review

The high morbidity and mortality rates associated with invasive fungal infections have led to the overutilization of empiric antifungal therapies. With increasing antibiotic resistance, the careful consideration of prophylactic or empiric antifungal use is critical. The purpose of this review is to evaluate the available literature regarding the current practice of utilizing antifungal agents for intra-abdominal infections based on specific surgical procedures and patient risk factors. Relevant articles were identified through a comprehensive literature search of several databases using the keywords antifungal agents, postoperative period, preoperative care, surgical procedures, and intra-abdominal infections. Only articles that evaluated the use of empiric antifungals for suspected or confirmed intra-abdominal infections and surgical procedures were included in this review. Based on the available literature, antifungal prophylaxis is appropriate in patients who meet the criteria for high-risk invasive candidiasis, kidney or liver transplant recipients, severely-immunocompromised patients with perforated peptic ulcer, peritonitis, and patients on peritoneal dialysis who are failing on a therapeutic antibiotic regimen. We acknowledge that the evidence for using antifungal therapy empirically for all surgical procedures is lacking, and the following review is based on available literature and current guidelines.

COVID-19 Is an Independent Risk Factor for Detrimental Invasive Fungal Disease in Patients on Veno-Venous Extracorporeal Membrane Oxygenation: A Retrospective Study

Invasive fungal disease (IFD) is associated with the mortality of patients on extracorporeal membrane oxygenation (ECMO). Several risk factors for IFD have been identified in patients with or without ECMO. Here, we assessed the relevance of coronavirus disease (COVID-19) for the occurrence of IFD in patients on veno-venous (V-V) ECMO for respiratory failure. In a retrospective analysis of all ECMO cases between January 2013 and December 2022 (2020-2022 for COVID-19 patients), active COVID-19 and the type, timing and duration of IFD were investigated. Demographics, hospital, ICU length of stay (LoS), duration of ECMO, days on invasive mechanical ventilation, prognostic scores (Respiratory ECMO Survival Prediction (RESP) score, Charlson Comorbidity Index (CCI), Therapeutic Intervention Scoring System (TISS)-10, Sequential Organ Failure Assessment (SOFA) score and Simplified Acute Physiology Score (SAPS)-II) and length of survival were assessed. The association of COVID-19 with IFD was investigated using propensity score matching and uni- and multivariable logistic regression analyses. We identified 814 patients supported with ECMO, and 452 patients were included in further analyses. The incidence of IFD was 4.8% and 11.0% in patients without and with COVID-19, respectively. COVID-19 status represented an independent risk factor for IFD (OR 4.30; CI 1.72-10.85; p: 0.002; multivariable regression analysis). In patients with COVID-19, 84.6% of IFD was candidemia and 15.4% represented invasive aspergillosis (IA). All of these patients died. In patients on V-V ECMO, we report that COVID-19 is an independent risk factor for IFD, which is associated with a detrimental prognosis. Further studies are needed to investigate strategies of antifungal therapy or prophylaxis in these patients.

Invasive candidiasis: current clinical challenges and unmet needs in adult populations

Invasive candidiasis (IC) is a serious infection caused by several Candida species, and the most common fungal disease in hospitals in high-income countries. Despite overall improvements in health systems and ICU care in the last few decades, as well as the development of different antifungals and microbiological techniques, mortality rates in IC have not substantially improved. The aim of this review is to summarize the main issues underlying the management of adults affected by IC, focusing on specific forms of the infection: IC developed by ICU patients, IC observed in haematological patients, breakthrough candidaemia, sanctuary site candidiasis, intra-abdominal infections and other challenging infections. Several key challenges need to be tackled to improve the clinical management and outcomes of IC patients. These include the lack of global epidemiological data for IC, the limitations of the diagnostic tests and risk scoring tools currently available, the absence of standardized effectiveness outcomes and long-term data for IC, the timing for the initiation of antifungal therapy and the limited recommendations on the optimal step-down therapy from echinocandins to azoles or the total duration of therapy. The availability of new compounds may overcome some of the challenges identified and increase the existing options for management of chronic Candida infections and ambulant patient treatments. However, early identification of patients that require antifungal therapy and treatment of sanctuary site infections remain a challenge and will require further innovations.

Validation of an Automated System for the Extraction of a Wide Dataset for Clinical Studies Aimed at Improving the Early Diagnosis of Candidemia

There is increasing interest in assessing whether machine learning (ML) techniques could further improve the early diagnosis of candidemia among patients with a consistent clinical picture. The objective of the present study is to validate the accuracy of a system for the automated extraction from a hospital laboratory software of a large number of features from candidemia and/or bacteremia episodes as the first phase of the AUTO-CAND project. The manual validation was performed on a representative and randomly extracted subset of episodes of candidemia and/or bacteremia. The manual validation of the random extraction of 381 episodes of candidemia and/or bacteremia, with automated organization in structured features of laboratory and microbiological data resulted in ≥99% correct extractions (with confidence interval < ±1%) for all variables. The final automatically extracted dataset consisted of 1338 episodes of candidemia (8%), 14,112 episodes of bacteremia (90%), and 302 episodes of mixed candidemia/bacteremia (2%). The final dataset will serve to assess the performance of different ML models for the early diagnosis of candidemia in the second phase of the AUTO-CAND project.

Multifaceted Evaluation of Antibiotic Therapy as a Factor Associated with Candidemia in Non-Neutropenic Patients

We aimed to evaluate various aspects of antibiotic therapy as factors associated with candidemia in non-neutropenic patients. A retrospective, matched, case-control study was conducted in two teaching hospitals. Patients with candidemia (cases) were compared to patients without candidemia (controls), matched by age, intensive care unit admission, duration of hospitalization, and type of surgery. Logistic regression analyses were performed to identify factors associated with candidemia. A total of 246 patients were included in the study. Of 123 candidemia patients, 36% had catheter-related bloodstream infections (CRBSIs). Independent factors in the whole population included immunosuppression (adjusted odds ratio [aOR] = 2.195; p = 0.036), total parenteral nutrition (aOR = 3.642; p < 0.001), and anti-methicillin-resistant S. aureus (MRSA) therapy for ≥11 days (aOR = 5.151; p = 0.004). The antibiotic factor in the non-CRBSI population was anti-pseudomonal beta-lactam treatment duration of ≥3 days (aOR = 5.260; p = 0.008). The antibiotic factors in the CRBSI population included anti-MRSA therapy for ≥11 days (aOR = 10.031; p = 0.019). Antimicrobial stewardship that reduces exposure to these antibacterial spectra could help prevent the development of candidemia.

How to Identify Invasive Candidemia in ICU-A Narrative Review

The incidence of invasive fungal infection in ICUs has increased over time, and Candida spp. is the most common cause. Critical care patients are a particular set of patients with a higher risk of invasive fungal infections; this population is characterized by extensive use of medical devices such as central venous lines, arterial lines, bladder catheters, hemodialysis and mechanical intubation. Blood cultures are the gold standard diagnosis; still, they are not an early diagnostic technique. Mannan, anti-mannan antibody, 1,3-β-D-glucan, Candida albicans germ tube antibody, Vitek 2, PNA-FISH, MALDI-TOF, PCR and T2Candida panel are diagnostic promising microbiological assays. Scoring systems are tools to distinguish patients with low and high risk of infection. They can be combined with diagnostic tests to select patients for pre-emptive treatment or antifungal discontinuation. Candidemia is the focus of this narrative review, an approach to contributing factors and diagnosis, with an emphasis on critical care patients.

Development and validation of COVID-19 associated candidemia score (CAC-Score) in ICU patients

BACKGROUND

The development of candidemia is a highly fatal condition in severe COVID-19 infection.

OBJECTIVES

This study aimed to develop a candidemia prediction score in COVID-19 patient based on the patient's clinical characteristics, and healthcare-related factors during intensive care units (ICU) follow-up.

PATIENTS/METHODS

Severe COVID-19 patients hospitalised in ICU in Ankara City Hospital during the one-year period (August 15, 2020, and August 15, 2021) were included. After univariate analysis, multivariate analysis was applied using variable selection approach to investigate the effects of variables together and to create a score model for candidemia. Statistically significant factors were included in the development process of candida prediction score.

RESULTS

Of 1305 COVID-19 ICU patients, 139 had a candidemia episode. According to the final model, four variables, presence of central venous catheter (CVC) (OR 19.07, CI 8.12-44.8, p < .0001), multifocal colonisation (OR 2.28, CI 1.39-3.72, p 0.001), length of ICU stays ≥14 days (OR 3.62, CI 2.42-5.44, p < .0001) and corticosteroids (OR 0.51, CI 0.34-0.76, p 0.0011) were the only statistically significant independent risk factors for candidemia. Score model was demonstrated by a nomogram, and the risk for candidemia was calculated to be high in patients who scored ≥56 points by using the criteria [CVC = 51, multifocal colonisation = 14, prolonged hospitalisation = 23, no steroid use = 12 points]. The AUC of the score is 0.84 (CI 0.81-0.87).

CONCLUSION

We developed and validated an easy-to-use clinical prediction score for candidemia in severe COVID-19 infection. In COVID-19 ICU patients, the risk of candidemia is high if one of the other risk factors is present together with CVC.

The Changing Landscape of Invasive Fungal Infections in ICUs: A Need for Risk Stratification to Better Target Antifungal Drugs and the Threat of Resistance

The landscape of invasive candidiasis and invasive aspergillosis has changed dramatically in intensive care units over the past two decades. Today, we are faced with new risk factors such as the emergence of resistance, but are also equipped with new therapeutic strategies and diagnostic tools which are changing epidemiological data and diagnostic algorithms. Some common points need to be addressed: (i) the best way to use microbiological tools and to integrate their results in decisional algorithms; (ii) the need to find the optimum balance between under-diagnosis and overtreatment; (iii) and the need to decipher pathophysiology. In this short review, we will try to illustrate these points.

Impact of the antimicrobial stewardship program on hospital-acquired candidemia

Antibiotic stewardship programs reduce antibiotic use without negative clinical outcomes. However, epidemiological data describing the relationship between implementing antimicrobial stewardship and candidemia incidence are scarce. This study aimed to evaluate the effect of antibiotic stewardship on the incidence of hospital acquired candidemia. We conducted a retrospective study from April 2017 to September 2020. We reviewed patients that were treated with three broad-spectrum antipseudomonal agents: carbapenem, tazobactam/piperacillin, and cefepime. Monthly aggregated hospital antimicrobial consumption was measured as days of therapy (DOTs) per 1000 patient-days, and the monthly incidence of hospital acquired candidemia was recorded. The median monthly carbapenem-DOTs during pre-intervention and intervention were 28.4 and 10.0, respectively. Time-series analysis showed significant level changes after intervention: - 10.0 DOTs (p = 0.02). There was a downward trend in the monthly carbapenem-DOTs after intervention. The median hospital-acquired candidemia incidence was 0.17 and 0.08 per 1000 patient-days during pre-intervention and intervention periods, respectively. Time-series analysis showed a significant level change after intervention (- 0.16 per 1000 patient-days; p = 0.048). The trend in the incidence of hospital-acquired candidemia did not significantly change between pre-intervention and intervention. Decreased broad-spectrum antibiotic use (particularly carbapenem) by our antimicrobial stewardship term may reduce hospital-acquired candidemia incidences.

Performance of existing clinical scores and laboratory tests for the diagnosis of invasive candidiasis in critically ill, nonneutropenic, adult patients: a systematic review with qualitative evidence synthesis

BACKGROUND

The Fungal Infections Definitions in Intensive Care Unit (ICU) patients (FUNDICU) project aims to provide standard sets of definitions for invasive fungal diseases in critically ill, adult patients.

OBJECTIVES

To summarize the available evidence on the diagnostic performance of clinical scores and laboratory tests for invasive candidiasis (IC) in nonneutropenic, adult critically ill patients.

METHODS

A systematic review was performed to evaluate studies assessing the diagnostic performance for IC of clinical scores and/or laboratory tests vs. a reference standard or a reference definition in critically ill, nonneutropenic, adult patients in ICU.

RESULTS

Clinical scores, despite the heterogeneity of study populations and IC prevalences, constantly showed a high negative predictive value (NPV) and a low positive predictive value (PPV) for the diagnosis of IC in the target population. Fungal antigen-based biomarkers (with most studies assessing serum beta-D-glucan) retained a high NPV similar to that of clinical scores, with a higher PPV, although the latter showed important heterogeneity across studies, possibly reflecting the targeted or untargeted use of these tests in patients with a consistent clinical picture and risk factors for IC.

CONCLUSIONS

Both clinical scores and laboratory tests showed high NPV for the diagnosis of IC in nonneutropenic critically ill patients. The PPV of laboratory tests varies significantly according to the baseline patients' risk of IC. This qualitative synthesis will provide the FUNDICU panel with baseline evidence to be considered during the development of definitions of IC in critically ill, nonneutropenic adult patients in ICU.

Rapid Detection of Bacterial and Fungal Pathogens Using the T2MR versus Blood Culture in Patients with Severe COVID-19

A high rate of bacterial and fungal superinfections was reported in critically ill patients with COVID-19. However, diagnosis can be challenging. The aim of this study is to evaluate the sensitivity and the clinical utility of the point-of-care method T2 magnetic resonance (T2MR) with the gold standard: the blood culture. T2MR can potentially detect five different Candida species and six common bacteria (so-called "ESKAPE" pathogens including Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Acinet`obacter baumanii, Pseudomonas aeruginosa, and Enterococcus faecium). If superinfection was suspected in patients with COVID-19 admitted to the intensive care unit, blood culture and two panels of T2MR were performed. Eighty-five diagnostic bundles were performed in 60 patients in total. T2MR detected an ESKAPE pathogen in 9 out of 85 (10.6%) samples, compared to BC in 3 out of 85 (3.5%). A Candida species was detected in 7 of 85 (8.2%) samples of T2MR compared to 1 out of 85(1.2%) in blood culture. The mean time to positive test result in samples with concordant positive results was 4.5 h with T2MR and 52.5 h with blood culture. The additional use of T2MR enables a highly sensitive and rapid detection of ESKAPE and Candida pathogens. IMPORTANCE Coronavirus disease 2019 (COVID-19) has led to a high number of deaths since the beginning of the pandemic worldwide. One of the reasons is the high number of bacterial and fungal superinfections in patients suffering from critical disease. However, diagnosis is often challenging. In this study we could show that the additional use of the culture-independent method T2MR did not only show a much higher detection rate of bacterial and fungal pathogens but also a significantly shorter time until detection and therapy change compared to the gold standard: the blood culture. The implementation of T2MRin the care of patients with severe course of COVID-19 might lead to an earlier sufficient antimicrobial therapy and as a result lower mortality and less use of broad-spectrum unnecessary therapy reducing the risk of resistance development.

Incidence and risk factors for COVID-19 associated candidemia (CAC) in ICU patients

BACKGROUND

Critically ill COVID-19 patients have a high risk for the development of candidemia due to being exposed to both well-defined classical risk factors and COVID-19-specific risk factors in ICU.

OBJECTIVES

In this study, we investigated the incidence of candidemia in critically COVID-19 patients, and the independent risk factors for candidemia.

PATIENTS/METHODS

COVID-19 patients hospitalised in ICU during 1-year period (August 2020 to August 2021) were included. Clinical and laboratory characteristics of all COVID-19 patients, applied treatments, and invasive procedures that may predispose to candidemia were recorded.

RESULTS

Of 1229 COVID-19 patients, 63 developed candidemia. Candidemia incidence rate was 4.4 episodes per 1000 ICU days. The most common species was Candida albicans (52.3%). Only 37 patients (58.7%) received antifungal therapy. The presence of central venous catheter (OR 4.7, 95% CI 1.8-12.2, p < .005), multifocal candida colonisation (OR 2.7, 95% CI 1.4-5.2, p < .005), a prolonged ICU stay (≥14 days) (OR 1.9, 95% CI 1.08-3-37, p < .05), the absence of chronic lung disease (OR 0.4, 95% CI 0.1-0.9, p < .05) and the absence of corticosteroid use (OR 0.3, 95% CI 0.14-0.52, p < .0001) were significantly associated with candidemia.

CONCLUSIONS

Our study filled the knowledge gap in the literature about the impact of COVID-19-associated risk factors for the development of candidemia. The classical risk factors for candidemia had a significant effect on candidemia, and contrary to expectations, corticosteroids had a protective effect against the development of candidemia. The results of these studies showing interesting effects of corticosteroids in critically ill COVID-19 patients should be confirmed by further studies.

TLR Signaling Rescues Fungicidal Activity in Syk-Deficient Neutrophils

An impaired neutrophil response to pathogenic fungi puts patients at risk for fungal infections with a high risk of morbidity and mortality. Acquired neutrophil dysfunction in the setting of iatrogenic immune modulators can include the inhibition of critical kinases such as spleen tyrosine kinase (Syk). In this study, we used an established system of conditionally immortalized mouse neutrophil progenitors to investigate the ability to augment Syk-deficient neutrophil function against Candida albicans with TLR agonist signaling. LPS, a known immunomodulatory molecule derived from Gram-negative bacteria, was capable of rescuing effector functions of Syk-deficient neutrophils, which are known to have poor fungicidal activity against Candida species. LPS priming of Syk-deficient mouse neutrophils demonstrates partial rescue of fungicidal activity, including phagocytosis, degranulation, and neutrophil swarming, but not reactive oxygen species production against C. albicans, in part due to c-Fos activation. Similarly, LPS priming of human neutrophils rescues fungicidal activity in the presence of pharmacologic inhibition of Syk and Bruton's tyrosine kinase (Btk), both critical kinases in the innate immune response to fungi. In vivo, neutropenic mice were reconstituted with wild-type or Syk-deficient neutrophils and challenged i.p. with C. albicans. In this model, LPS improved wild-type neutrophil homing to the fungal challenge, although Syk-deficient neutrophils did not persist in vivo, speaking to its crucial role on in vivo persistence. Taken together, we identify TLR signaling as an alternate activation pathway capable of partially restoring neutrophil effector function against Candida in a Syk-independent manner.

Retrospective Evaluation of Risk Factors for Invasive Candida Infections in a Medical Intensive Care Unit

Objective

We aimed to detect the risk factors for invasive candida infections by evaluating the fungal strains cultivated from samples taken in a medical intensive care unit (ICU).

Materials and Methods

We investigated fungal growths between January 1, 2016, and December 1, 2018, retrospectively. All reported fungal growths and demographic characteristics, clinical features, treatments and outcomes of the patients with fungal growths were recorded.

Results

Fungal growths were reported from 384 different samples obtained from 179 ICU patients. The most common strain was determined to be C. albicans (47.9%).The incidence of non-albicansCandida strains was increased over the years (2016 - 44%, 2017 - 52.5%, 2018 - 49%), most significantly C. glabrata (7.7% to 14.6%). The most common strain was C. parapsilosis (57.9%) in patients with candidemia, and infection was more severe among them. Fluconazole resistance was rare. When patients with and without fungal growth were compared, a significant difference was found between groups in terms of age, acute physiology and chronic health evaluation II (APACHE II) score, length of ICU and hospital stay, ICU and hospital mortality (p<0.001, p =0.011, p<0.001, p=0.031, p =0.016). Candida score was significantly higher in candidemic patients (3.0 vs 0.0 p<0.001).

Conclusion

Among fungal growths in samples from critically ill patients, the incidence of non-albicans Candida strains was gradually increasing. Older age, higher APACHE II score, and longer hospital and ICU stay were associated with fungal growths.

Investigation of the Emerging Nosocomial Wickerhamomyces anomalus Infections at a Chinese Tertiary Teaching Hospital and a Systemic Review: Clinical Manifestations, Risk Factors, Treatment, Outcomes, and Anti-fungal Susceptibility

Wickerhamomyces anomalus is an emerging pathogen, which has been associated with clonal outbreaks and poor clinical outcomes. Despite being an important emerging yeasts species, our understanding concerning the microbiological and clinical characteristics of infections due to this species is limited. Herein, we are reporting a retrospective analysis of fungemia patients with W. anomalus from a 2,100-bed hospital in Shanghai during 2014–2016. Moreover, we conducted an extensive literature review to gain a deeper clinical and microbiological insights. Detailed clinical data were recorded. Antifungal susceptibility testing (AFST) followed CLSI M27-A3, and isolates were identified using MALDI-TOF MS. In total, 13 patients were identified with a mortality rate of 38.5% (5/13). Central venous catheter (CVC), broad-spectrum antibiotic therapy, total parenteral nutrition (TPN), surgery, and mechanical ventilation were the most frequently observed risk factors. Eight patients (61.5%) experienced mixed bacterial/Candida bloodstream infections, and four patients developed mixed candidemia (MC). W. anomalus isolates showed high minimum inhibitory concentrations (MICs) against all azoles tested and flucytosine, while AMB showed the highest in vitro activity. Azoles were used for 84.6% (11/13) of the cases, while 36.4% (4/11) of them died. When combining with the AFST data and the literature review, our study highlights the poor efficacy of azoles and optimal efficacy of AMB and LAMB against infections caused by W. anomalus. In conclusion, our study highlights the emerging threat of W. anomalus affecting both neonates and adults. Furthermore, our results advocate the use of AMB formulations rather than azoles among patients infected with W. anomalus. Future studies are warranted to reach a definitive consensus regarding the utility of echinocandins among such patients.

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.

Using Machine Learning Algorithms to Predict Candidaemia in ICU Patients With New-Onset Systemic Inflammatory Response Syndrome

Background: Distinguishing ICU patients with candidaemia can help with the precise prescription of antifungal drugs to create personalized guidelines. Previous prediction models of candidaemia have primarily used traditional logistic models and had some limitations. In this study, we developed a machine learning algorithm trained to predict candidaemia in patients with new-onset systemic inflammatory response syndrome (SIRS).

Methods: This retrospective, observational study used clinical information collected between January 2013 and December 2017 from three hospitals. The ICU patient data were used to train 4 machine learning algorithms–XGBoost, Support Vector Machine (SVM), Random Forest (RF), ExtraTrees (ET)–and a logistic regression (LR) model to predict patients with candidaemia.

Results: Of the 8,002 cases of new-onset SIRS (in 7,932 patients) included in the analysis, 137 new-onset SIRS cases (in 137 patients) were blood culture positive for candidaemia. Risk factors, such as fungal colonization, diabetes, acute kidney injury, the total number of parenteral nutrition days and renal replacement therapy, were important predictors of candidaemia. The XGBoost machine learning model outperformed the other models in distinguishing patients with candidaemia [XGBoost vs. SVM vs. RF vs. ET vs. LR; area under the curve (AUC): 0.92 vs. 0.86 vs. 0.91 vs. 0.90 vs. 0.52, respectively]. The XGBoost model had a sensitivity of 84%, specificity of 89% and negative predictive value of 99.6% at the best cut-off value.

Conclusions: Machine learning algorithms can potentially predict candidaemia in the ICU and have better efficiency than previous models. These prediction models can be used to guide antifungal treatment for ICU patients when SIRS occurs.

Monocyte human leukocyte antigen-DR but not β-D-glucan may help early diagnosing invasive Candida infection in critically ill patients

Background

Precision medicine risk stratification is desperately needed to both avoid systemic antifungals treatment delay and over prescription in the critically ill with risk factors. The aim of the present study was to explore the combination of host immunoparalysis biomarker (monocyte human leukocyte antigen-DR expression (mHLA-DR)) and Candida sp wall biomarker β-d-glucan in risk stratifying patients for secondary invasive Candida infection (IC).

Methods

Prospective observational study. Two intensive care units (ICU). All consecutive non-immunocompromised septic shock patients. Serial blood samples (n = 286) were collected at day 0, 2 and 7 and mHLA-DR and β-d-glucan were then retrospectively assayed after discharge. Secondary invasive Candida sp infection occurrence was then followed at clinicians’ discretion.

Results

Fifty patients were included, 42 (84%) had a Candida score equal or greater than 3 and 10 patients developed a secondary invasive Candida sp infection. ICU admission mHLA-DR expression and β-d-glucan (BDG) failed to predict secondary invasive Candida sp infection. Time-dependent cause-specific hazard ratio of IC was 6.56 [1.24–34.61] for mHLA-DR < 5000 Ab/c and 5.25 [0.47–58.9] for BDG > 350 pg/mL. Predictive negative value of mHLA-DR > 5000 Ab/c and BDG > 350 pg/mL combination at day 7 was 81% [95% CI 70–92].

Conclusions

This study suggests that mHLA-DR may help predicting IC in high-risk patients with septic shock. The added value of BDG and other fungal tests should be regarded according to the host immune function markers.

Clinical predictive models of invasive Candida infection: a systematic literature review

Clinical predictive models (CPM) serve to identify and categorize patients into risk categories to assist in treatment and intervention recommendations. Predictive accuracy and practicality of models varies depending on methods used for their development, and should be evaluated.The aim of this study was to summarize currently available CPM for invasive candidiasis, analyze their performance, and assess their suitability for use in clinical decision making.We identified studies that described the construction of a CPM for invasive candidiasis from PubMed/MEDLINE, EMBASE, SCOPUS, Web of Science, Cochrane Library databases and Clinicaltrials.gov. Data extracted included: author, data source, study design, recruitment period, characteristics of study population, outcome types, predictor types, number of study participants and outcome events, modelling method and list of predictors used in the final model. Calibration and discrimination in the derivative datasets were used to assess the performance of each model.Ten articles were identified in our search and included for full text review. Five models were developed using data from ICUs, and five models included all hospitalized patients. The findings of this review highlight the limitations of currently available models to predict invasive candidiasis, including lack of generalizability, difficulty in everyday clinical use, and overly optimistic performance.There are significant concerns regarding predictive performance and usability in every day practice of existing CPM to predict invasive candidiasis.

LAY SUMMARY

Clinical predictive models may assist in early identification of patients at risk for invasive candidiasis to initiate appropriate treatment. The findings of this systematic review highlight the limitations of currently available models to predict invasive candidiasis.

An approach to develop clinical prediction rule for candidemia in critically ill patients: A retrospective observational study

PURPOSE

Early detection of candidemia in critically ill patients is important for preemptive antifungal treatment. Our study aimed to identify the independent risk factors for the development of a new candidemia prediction score.

METHODS

This single-centre retrospective observational study evaluated 2479 intensive care unit (ICU) cases from January 2016 to December 2018. A total of 76 identified candidemia cases and 76 matched control cases were analyzed. The patients' demographic characteristics and illness severity were analyzed, and possible risk factors for candidemia were investigated.

RESULTS

Multivariate logistic regression analysis identified renal replacement therapy (RRT) (odds ratio [OR]: 52.83; 95% confidence interval [CI]: 7.82-356.92; P < 0.0001), multifocal Candida colonization (OR: 23.55; 95% CI: 4.23-131.05; P < 0.0001), parenteral nutrition (PN) (OR: 63.67; 95% CI: 4.56-889.77; P = 0.002), and acute kidney injury (AKI) (OR: 7.67; 95% CI: 1.24-47.30; P = 0.028) as independent risk factors. A new prediction score with a cut-off value of 5.0 (80.3% sensitivity and 77.3% specificity) was formulated from the logit model equation.

CONCLUSIONS

Renal replacement therapy, AKI, PN, and multifocal Candida colonization were the independent risk factors for the new candidemia prediction score with high discriminatory performance and predictive accuracy.

Mind the gaps: challenges in the clinical management of invasive candidiasis in critically ill patients

PURPOSE OF REVIEW

Strict adherence to clinical practice guidelines is recognized to improve outcomes but the inconvenient truth is that only a small subset of what is done in medicine has been tested in appropriate, well designed studies. In this article, we aim to review controversial aspects of the clinical management of invasive candidiasis recommended by guidelines.

RECENT FINDINGS

Despite still being recommended by guidelines, we fail to identify a single randomized clinical trial documenting that the use of antifungal drugs in high-risk critically ill patients without microbiologic documentation of Candida infection decreases mortality. Regarding deep-seated Candida infections, most cohort studies of patients with candidemia found less than 5% of patients developed endophthalmitis and endocarditis. In this scenario, it is reasonable to reconsider routine universal screening of both complications in candidemic patients. Finally, a large number of studies have shown that critically ill patients usually have lower echinocandin exposure when compared with other populations. We need more data on the clinical relevance of this finding.

SUMMARY

We need robust studies to validate new strategies for the clinical management of candidemia in ICU, including: the use of fungal biomarkers in the early initiation or interruption of antifungal therapy in high-risk patients to replace the conventional empirical antifungal therapy driven by predictive rules; validation of targeted screening of eye infection and endocarditis with the aid of fungal biomarkers only in high-risk patients; we should clarify if higher doses of candins are necessary to treat invasive candidiasis in critically ill patients, especially in the case of intra-abdominal infections where drug penetration is suboptimal.

Post-Prescription Audit Plus Beta-D-Glucan Assessment Decrease Echinocandin Use in People with Suspected Invasive Candidiasis

Background and Objectives: Overtreatment with antifungal drugs is often observed. Antifungal stewardship (AFS) focuses on optimizing the treatment for invasive fungal diseases. The objective of the present study was to evaluate the utility of a post-prescription audit plus beta-D-glucan (BDG) assessment on reducing echinocandin use in persons with suspected invasive candidiasis. Materials and Methods: This is a prospective, pre-post quasi-experimental study of people starting echinocandins for suspected invasive candidiasis. The intervention of the study included review of each echinocandin prescription and discontinuation of treatment if a very low probability of fungal disease or a negative BDG value were found. Pre-intervention data were compared with the intervention phase. The primary outcome of the study was the duration of echinocandin therapy. Secondary outcomes were length of hospital stay and mortality. Results: Ninety-two echinocandin prescriptions were reviewed, 49 (53.3%) in the pre-intervention phase and 43 (46.7%) in the intervention phase. Discontinuation of antifungal therapy was possible in 21 of the 43 patients in the intervention phase (48.8%). The duration of echinocandin therapy was 7.4 (SD 4.7) in the pre-intervention phase, 4.1 days (SD 2.9) in persons undergoing the intervention, and 8.6 (SD 7.3) in persons in whom the intervention was not feasible (p at ANOVA = 0.016). Length of stay and mortality did not differ between pre-intervention and intervention phases. Conclusions: An intervention based on pre-prescription restriction and post-prescription audit when combined with BDG measurement is effective in optimizing antifungal therapy by significantly reducing excessive treatment duration.

Roles of the multiplex real-time PCR assay and β-D-glucan in a high-risk population for intra-abdominal candidiasis (IAC)

Multiplex quantitative real-time PCR (MRT-PCR) using blood can improve the diagnosis of intra-abdominal candidiasis (IAC). We prospectively studied 39 patients with suspected IAC in the absence of previous antifungal therapy. Blood cultures, MRT-PCR, and β-D-glucan (BDG) in serum were performed in all patients. IAC was defined according to the 2013 European Consensus criteria. For MRT-PCR, the probes targeted the ITS1 or ITS2 regions of ribosomal DNA. Candidaemia was confirmed only in four patients (10%), and IAC criteria were present in 17 patients (43.6%). The sensitivity of MRT-PCR was 25% but increased to 63.6% (P = .06) in plasma obtained prior to volume overload and transfusion; specificity was above 85% in all cases. BDG performance was improved using a cutoff > 260 pg/ml, and improvement was not observed in samples obtained before transfusion. In this cohort of high risk of IAC and low rate of bloodstream infection, the performance of non-culture-based methods (MRT-PCR or BDG) was moderate but may be a complementary tool given the limitations of diagnostic methods available in clinical practice. Volume overload requirements, in combination with other factors, decrease the accuracy of MRT-PCR in patients with IAC.

EORTC/MSGERC Definitions of Invasive Fungal Diseases: Summary of Activities of the Intensive Care Unit Working Group

The EORTC/MSGERC recently revised and updated the consensus definitions of invasive fungal disease (IFD). These definitions primarily focus on patients with cancer and stem cell or solid-organ transplant patients. They may therefore not be suitable for intensive care unit (ICU) patients. More in detail, while the definition of proven IFD applies to a broad range of hosts, the categories of probable and possible IFD were primarily designed for classical immunocompromised hosts and may therefore not be ideal for other populations. Moreover, the scope of the possible category of IFD has been diminished in the recently revised definitions for classically immunocompromised hosts. Diagnosis of IFD in the ICU presents many challenges, which are different for invasive candidiasis and for invasive aspergillosis. The aim of this article is to review progresses made in recent years and difficulties remaining in the development of definitions applicable in the ICU setting.

Invasive Candida Infections in Neonates after Major Surgery: Current Evidence and New Directions

Infections represent a serious health problem in neonates. Invasive Candida infections (ICIs) are still a leading cause of mortality and morbidity in neonatal intensive care units (NICUs). Infants hospitalized in NICUs are at high risk of ICIs, because of several risk factors: broad spectrum antibiotic treatments, central catheters and other invasive devices, fungal colonization, and impaired immune responses. In this review we summarize 19 published studies which provide the prevalence of previous surgery in neonates with invasive Candida infections. We also provide an overview of risk factors for ICIs after major surgery, fungal colonization, and innate defense mechanisms against fungi, as well as the roles of different Candida spp., the epidemiology and costs of ICIs, diagnosis of ICIs, and antifungal prophylaxis and treatment.

An evaluation of ibrexafungerp for the treatment of invasive candidiasis: the evidence to date

INTRODUCTION

Invasive fungal infections, especially candidemia and invasive candidiasis, cause significant morbidity and mortality. The epidemiology of candida infections have changed dramatically due to an increase in risk factors associated with the development of infection and the emergence of resistant isolates such as C. glabrata and C. auris. This has prompted the search for novel and effective antifungals.

AREAS COVERED

The results of in vitro studies evaluating the activity of ibrexafungerp against Candida species are reviewed and the pharmacokinetic/pharmacodynamic properties are highlighted. Available results and safety data from limited clinical studies are discussed.

EXPERT OPINION

Ibrexafungerp demonstrates potent in vitro activity against susceptible and resistant Candida species, including echinocandin-resistant C. glabrata and multidrug-resistant C. auris. It also offers the flexibility of a parenteral and an oral preparation, minimal adverse effects, and low drug-drug interactions. In Phase 2/3 clinical trials, ibrexafungerp appears to have excellent clinical activity in patients with candidemia, invasive candidiasis, and mucosal candidiasis. Although there are several ongoing clinical trials, ibrexafungerp appears to be a promising agent and an important addition to the antifungal armamentarium necessary to treat emerging and resistant pathogens, including several of the Candida species.

Emerging Clinical Features of COVID-19 Related Pancreatitis: Case Reports and Review of the Literature

INTRODUCTION

SARS-CoV-2 is fundamentally a respiratory pathogen with a wide spectrum of symptoms. The COVID-19 related pancreatitis is less considered than other clinical features. The purpose is to describe two cases of pancreatitis associated with COVID-19.

METHODOLOGY

Patients' demographics, clinical features, laboratory, and instrumental findings were collected.

RESULTS

Two patients admitted to the hospital were diagnosed with COVID-19 and severe acute pancreatitis, according to the Atlanta criteria. Other causes of acute pancreatitis were excluded. Treatment included broad-spectrum antibiotics, proton pump inhibitors, and low molecular weight heparin. Steroids, oxygen, antifungal treatment, and pain killers were administered when appropriate. Both patients were asymptomatic, with normal vital parameters and blood exams, and were discharged in a good condition.

CONCLUSION

It is recommendable to include lipase and amylase on laboratory routine tests in order to evaluate the need for the abdominal CT-scan and specific therapy before hospital admission of the patients with COVID-19 related life-threatening acute pancreatitis.

Optimal Antibiotic Duration for Bloodstream Infections Secondary to Intraabdominal Infection

BACKGROUND

Bloodstream infections (BSIs) secondary to intraabdominal infections (IAIs) are common in the intensive care unit (ICU). The Surgical Infection Society guidelines recommend treatment duration after achieving source control in patients with secondary bacteremia; however, literature supporting this recommendation is limited. The purpose of this study was to compare outcomes in patients who received shorter versus extended duration of antibiotics for bacteremia secondary to IAI.

MATERIALS AND METHODS

A retrospective cohort analysis was conducted in adult surgical ICU patients (n = 42) with BSIs and source control procedure(s) for IAI. The primary outcome was recurrent IAI. Secondary outcomes included surgical site infections (SSIs), Clostridium difficile infections (CDIs), secondary fungal infections, and in-hospital mortality.

RESULTS

Forty-two patients met inclusion criteria and were divided into groups according to antimicrobial duration; 12 patients received <7 d, and 30 patients received >7 d of antibiotics. There were no differences in baseline characteristics between the two cohorts except for the presence of sepsis [4/12 (33.3%) versus 27/30 (90.0%); P = 0.001]. Thirty-one percent (13/42) of all organisms isolated from blood cultures were gram-negative bacteria, 12/42 (28.6%) were MDROs, and 2/42 (4.8%) patients experienced a culture mismatch in which cultured bacteria were not susceptible to empiric antibiotic therapy. Rates of recurrent IAI were similar between the two cohorts [1/12 (8.3%) versus 4/30 (13.3%), P = 0.554].

CONCLUSIONS

Among surgical ICU patients with BSI secondary to IAI, cessation of antibiotic therapy within 7 d of source control was not associated with an increased incidence of recurrent IAI.

Risk Factors for Candidemia After Open Heart Surgery: Results From a Multicenter Case-Control Study

BACKGROUND

Candida species are among the most frequent causative agents of health care-associated bloodstream infections, with mortality >40% in critically ill patients. Specific populations of critically ill patients may present peculiar risk factors related to their reason for intensive care unit admission. The primary objective of the present study was to assess the predictors of candidemia after open heart surgery.

METHODS

This retrospective, matched case-control study was conducted in 8 Italian hospitals from 2009 to 2016. The primary study objective was to assess factors associated with the development of candidemia after open heart surgery.

RESULTS

Overall, 222 patients (74 cases and 148 controls) were included in the study. Candidemia developed at a median time (interquartile range) of 23 (14-36) days after surgery. In multivariable analysis, independent predictors of candidemia were New York Heart Association class III or IV (odds ratio [OR], 23.81; 95% CI, 5.73-98.95; P < .001), previous therapy with carbapenems (OR, 8.87; 95% CI, 2.57-30.67; P = .001), and previous therapy with fluoroquinolones (OR, 5.73; 95% CI, 1.61-20.41; P = .007). Crude 30-day mortality of candidemia was 53% (39/74). Septic shock was independently associated with mortality in the multivariable model (OR, 5.64; 95% CI, 1.91-16.63; P = .002). No association between prolonged cardiopulmonary bypass time and candidemia was observed in this study.

CONCLUSIONS

Previous broad-spectrum antibiotic therapy and high NYHA class were independent predictors of candidemia in cardiac surgery patients with prolonged postoperative intensive care unit stay.

Personalized machine learning approach to predict candidemia in medical wards

PURPOSE

Candidemia is a highly lethal infection; several scores have been developed to assist the diagnosis process and recently different models have been proposed. Aim of this work was to assess predictive performance of a Random Forest (RF) algorithm for early detection of candidemia in the internal medical wards (IMWs).

METHODS

A set of 42 potential predictors was acquired in a sample of 295 patients (male: 142, age: 72 ± 15 years; candidemia: 157/295; bacteremia: 138/295). Using tenfold cross-validation, a RF algorithm was compared with a classic stepwise multivariable logistic regression model; discriminative performance was assessed by C-statistics, sensitivity and specificity, while calibration was evaluated by Hosmer-Lemeshow test.

RESULTS

The best tuned RF algorithm demonstrated excellent discrimination (C-statistics = 0.874 ± 0.003, sensitivity = 84.24% ± 0.67%, specificity = 91% ± 2.63%) and calibration (Hosmer-Lemeshow statistics = 12.779 ± 1.369, p = 0.120), markedly greater than the ones guaranteed by the classic stepwise logistic regression (C-statistics = 0.829 ± 0.011, sensitivity = 80.21% ± 1.67%, specificity = 84.81% ± 2.68%; Hosmer-Lemeshow statistics = 38.182 ± 15.983, p < 0.001). In addition, RF suggests a major role of in-hospital antibiotic treatment with microbioma highly impacting antimicrobials (MHIA) that are found as a fundamental risk of candidemia, further enhanced by TPN. When in-hospital MHIA therapy is not performed, PICC is the dominant risk factor for candidemia, again enhanced by TPN. When PICC is not used and MHIA therapy is not performed, the risk of candidemia is minimum, slightly increased by in-hospital antibiotic therapy.

CONCLUSION

RF accurately estimates the risk of candidemia in patients admitted to IMWs. Machine learning technique might help to identify patients at high risk of candidemia, reduce the delay in empirical treatment and improve appropriateness in antifungal prescription.

Evaluation of the updated "Candida score" with Sepsis 3.0 criteria in critically ill patients

Background

The Candida score proposed in 2009 was calculated on the definition of “severe sepsis”, which was removed in the Sepsis 3.0 definition. This study investigated the clinical relevance of Candida score with the updated Sepsis 3.0 definition (CS-3.0) instead of severe sepsis (CS-2009) in the new admitted critically ill patients.

Methods

We performed a retrospective analysis on a single center public database. All patients with ICU stay ≥72 hours were included in this study. The Candida score was calculated based on the data collected on ICU admission. The incidence of invasive candidiasis was determined and its relationship with the CS-2009 and CS-3.0 was studied.

Results

A total of 17,666 patients were identified after screening 58,976 hospital admissions, and 436 cases (2.5%) were diagnosed with invasive candidiasis. In the infection group, the number of patients who met the Sepsis 3.0 criteria was greater than the number of patients with severe sepsis (81.2% vs. 78.4%, P<0.005). The area under curve of the CS-2009 was 0.789 (95% CI: 0.765–0.813) and the CS-3.0 was 0.804 (95% CI: 0.782–0.827).

Conclusions

Our study confirmed the clinical relevance and comparative superiority of the updated Candida score model, using the Sepsis 3.0 definition, compared with the classic sepsis/severe sepsis model, in assessment of critically ill patients. Considering the clinical importance of organ dysfunction in ICI, the Sepsis 3.0 should be used as the basis for prediction of invasive candidiasis.

Association of Immune Cell Subtypes and Phenotype With Subsequent Invasive Candidiasis in Patients With Abdominal Sepsis

BACKGROUND

In nonneutropenic intensive care unit (ICU) patients, current risk stratification scores lack specificity to reliably predict the risk of a prospective invasive candidiasis (IC). We aimed to explore possible associations of distinct immunological markers with different degrees of Candida affection in patients with abdominal sepsis.

METHODS

The presented explorative, noninterventional diagnosis study recruited patients admitted to the surgical ICU at Heidelberg University Hospital with abdominal sepsis. Over 5 days, we determined white blood cell count, 1,3-β-D-glucan, and HLA-DR expression; the amount of Th1, Th17, regulatory T, T helper, and cytotoxic T cells; Dectin-1 and TLR2-expression; the amount of T, B, and NK cells; the ex vivo secretion of IL-8 upon stimulation with LPS, flagellin, and zymosan; and the distribution of distinct T-cell cytokines in a daily manner. On day 21, patients' Candida infection status was stratified in no colonization or IC, colonization or IC.

RESULTS

A total of 26 patients were included. On day 21, five patients showed no colonization or IC, in 13 patients a colonization was detected, and eight patients were diagnosed with IC. On study inclusion, the stratification groups showed comparable values in standard laboratory parameters and morbidity scores. Decreased B and NK cell counts, as well as reduced IL-8 secretion after ex vivo stimulation with LPS or flagellin seemed to be associated with a higher risk of subsequent Candida colonization. Even lower values could distinguish the therapy-relevant difference between prospective IC from colonization alone.

CONCLUSIONS

We were able to show distinct immune system impairments in early abdominal sepsis by specific immune-based measurements. A possible association of these impairments with a subsequent Candida affection is shown.

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.

Impact of the Beta-Glucan Test on Management of Intensive Care Unit Patients at Risk for Invasive Candidiasis

The 1,3-beta-d-glucan (BDG) test is used for the diagnosis of invasive candidiasis (IC) in intensive care units (ICUs). However, its utility for patient management is unclear. This study assessed the impact of BDG test results on therapeutic decisions. This was a single-center observational study conducted in an ICU over two 6-month periods. All BDG test requests for the diagnosis of IC were analyzed. Before the second period, the ICU physicians received a pocket card instruction (algorithm) for targeted BDG testing in high-risk patients. The performance of the BDG test for IC diagnosis was assessed, as well as its impact on antifungal (AF) prescription. Overall, 72 patients had ≥1 BDG test, and 14 (19%) patients had an IC diagnosis. The BDG test results influenced therapeutic decisions in 41 (57%) cases. The impact of the BDG test was positive in 30 (73%) of them, as follows: AF abstention/interruption following a negative BDG result (n = 27), and AF initiation/continuation triggered by a positive BDG test result and subsequently confirmed IC (n = 3). In 10 (24%) cases, a positive BDG test result resulted in AF initiation/continuation with no further evidence of IC. A negative BDG result and AF abstention with subsequent IC diagnosis were observed in one case. The positive predictive value (PPV) of BDG was improved if testing was restricted to the algorithm's indications (80% versus 36%, respectively). However, adherence to the algorithm was low (26%), and no benefit of the intervention was observed. The BDG result had an impact on therapeutic decisions in more than half of the cases, which consisted mainly of safe AF interruption/abstention. Targeted BDG testing in high-risk patients improves PPV but is difficult to achieve in ICU.

Risk factors for candidemia: a prospective matched case-control study

Background

Candidemia is an opportunistic infection associated with high morbidity and mortality in patients hospitalized both inside and outside intensive care units (ICUs). Identification of patients at risk is crucial to ensure prompt antifungal therapy. We sought to assess risk factors for candidemia and death, both outside and inside ICUs.

Methods

This prospective multicenter matched case-control study involved six teaching hospitals in Switzerland and France. Cases were defined by positive blood cultures for Candida sp. Controls were matched to cases using the following criteria: age, hospitalization ward, hospitalization duration, and, when applicable, type of surgery. One to three controls were enrolled by case. Risk factors were analyzed by univariate and multivariate conditional regression models, as a basis for a new scoring system to predict candidemia.

Results

One hundred ninety-two candidemic patients and 411 matched controls were included. Forty-four percent of included patients were hospitalized in ICUs, and 56% were hospitalized outside ICUs. Independent risk factors for candidemia in the ICU population included total parenteral nutrition, acute kidney injury, heart disease, prior septic shock, and exposure to aminoglycoside antibiotics. Independent risk factors for candidemia in the non-ICU population included central venous catheter, total parenteral nutrition, and exposure to glycopeptides and nitroimidazoles. The accuracy of the scores based on these risk factors is better in the ICU than in the non-ICU population. Independent risk factors for death in candidemic patients included septic shock, acute kidney injury, and the number of antibiotics to which patients were exposed before candidemia.

Discussion

While this study shows a role for known and novel risk factors for candidemia, it specifically highlights important differences in their distribution according to the hospital setting (ICU versus non-ICU).

Conclusion

This study provides novel risk scores for candidemia accounting for the hospital setting and recent progress in patients’ management strategies and fungal epidemiology.

Genotyping Reveals High Clonal Diversity and Widespread Genotypes of Candida Causing Candidemia at Distant Geographical Areas

The objectives of this study were to gain further insight on Candida genotype distribution and percentage of clustered isolates between hospitals and to identify potential clusters involving different hospitals and cities. We aim to genotype Candida spp. isolates causing candidemia in patients admitted to 16 hospitals in Spain, Italy, Denmark, and Brazil. Eight hundred and eighty-four isolates (Candida albicans, n = 534; C. parapsilosis, n = 282; and C. tropicalis, n = 68) were genotyped using species-specific microsatellite markers. CDC3, EF3, HIS3, CAI, CAIII, and CAVI were used for C. albicans, Ctrm1, Ctrm10, Ctrm12, Ctrm21, Ctrm24, and Ctrm28 for C. tropicalis, and CP1, CP4a, CP6, and B for C. parapsilosis. Genotypes were classified as singletons (genotype only found once) or clusters (same genotype infecting two or more patients). Clusters were defined as intra-hospital (involving patients admitted to a single hospital), intra-ward (involving patients admitted to the same hospital ward) or widespread (involving patients admitted to different hospitals). The percentage of clusters and the proportion of patients involved in clusters among species, genotypic diversity and distribution of genetic diversity were assessed. Seven hundred and twenty-three genotypes were detected, 78 (11%) being clusters, most of which (57.7%; n = 45/78) were intra-hospital clusters including intra-ward ones (42.2%; n = 19/45). The proportion of clusters was not statistically different between species, but the percentage of patients in clusters varied among hospitals. A number of genotypes (7.2%; 52/723) were widespread (found at different hospitals), comprising 66.7% (52/78) of clusters, and involved patients at hospitals in the same city (n = 21) or in different cities (n = 31). Only one C. parapsilosis cluster was a widespread genotype found in all four countries. Around 11% of C. albicans and C. parapsilosis isolates causing candidemia are clusters that may result from patient-to-patient transmission, widespread genotypes commonly found in unrelated patients, or insufficient microsatellite typing genetic discrimination.

The Overlooked Immune State in Candidemia: A Risk Factor for Mortality

Lymphopenia has been related to increased mortality in septic patients. Nonetheless, the impact of lymphocyte count on candidemia mortality and prognosis has not been addressed. We conducted a retrospective study, including all admitted patients with candidemia from 2007 to 2016. We examined lymphocyte counts during the first 5 days following the diagnosis of candidemia. Multivariable logistic regression analysis was performed to determine the relationship between lymphocyte count and mortality. Classification and Regression Tree analysis was used to identify the best cut-off of lymphocyte count for mortality associated with candidemia. From 296 cases of candidemia, 115 died, (39.8% 30-day mortality). Low lymphocyte count was related to mortality and poor outcome (p < 0.001). Lymphocyte counts <0.703 × 10⁹ cells/L at diagnosis (area under the curve (AUC)-ROC, 0.783 ± 0.042; 95% confidence interval (CI), 0.700-0.867, p < 0.001), and lymphocyte count <1.272 × 10⁹ cells/L five days later (AUC-ROC, 0.791 ± 0.038; 95%CI, 0.716-0.866, p < 0.001) increased the odds of mortality five-fold (odds ratio (OR), 5.01; 95%CI, 2.39-10.93) at time of diagnosis, and three-fold (OR, 3.27; 95%CI, 1.24-8.62) by day 5, respectively. Low lymphocyte count is an independent predictor of mortality in patients with candidemia and might serve as a biomarker for predicting candidemia-associated mortality and poor outcome.

Defining breakthrough invasive fungal infection-Position paper of the mycoses study group education and research consortium and the European Confederation of Medical Mycology

Breakthrough invasive fungal infections (IFIs) have emerged as a significant problem in patients receiving systemic antifungals; however, consensus criteria for defining breakthrough IFI are missing. This position paper establishes broadly applicable definitions of breakthrough IFI for clinical research. Representatives of the Mycoses Study Group Education and Research Consortium (MSG-ERC) and the European Confederation of Medical Mycology (ECMM) reviewed the relevant English literature for definitions applied and published through 2018. A draft proposal for definitions was developed and circulated to all members of the two organisations for comment and suggestions. The authors addressed comments received and circulated the updated document for approval. Breakthrough IFI was defined as any IFI occurring during exposure to an antifungal drug, including fungi outside the spectrum of activity of an antifungal. The time of breakthrough IFI was defined as the first attributable clinical sign or symptom, mycological finding or radiological feature. The period defining breakthrough IFI depends on pharmacokinetic properties and extends at least until one dosing interval after drug discontinuation. Persistent IFI describes IFI that is unchanged/stable since treatment initiation with ongoing need for antifungal therapy. It is distinct from refractory IFI, defined as progression of disease and therefore similar to non-response to treatment. Relapsed IFI occurs after treatment and is caused by the same pathogen at the same site, although dissemination can occur. These proposed definitions are intended to support the design of future clinical trials and epidemiological research in clinical mycology, with the ultimate goal of increasing the comparability of clinical trial results.

Gut Leakage of Fungal-Derived Inflammatory Mediators: Part of a Gut-Liver-Kidney Axis in Bacterial Sepsis

Sepsis is a life-threatening response to systemic infection. In addition to frank gastrointestinal (GI) rupture/puncture, sepsis can also be exacerbated by translocation of pathogen-associated molecular patterns (PAMPs) from the GI tract to the systemic circulation (gut origin of sepsis). In the human gut, Gram-negative bacteria and Candida albicans are abundant, along with their major PAMP components, endotoxin (LPS) and (1 → 3)-β-D-glucan (BG). Whereas the influence of LPS in bacterial sepsis has been studied extensively, exploration of the role of BG in bacterial sepsis is limited. Post-translocation, PAMPs enter the circulation through lymphatics and the portal vein, and are detoxified and then excreted via the liver and the kidney. Sepsis-induced liver and kidney injury might therefore affect the kinetics and increase circulating PAMPs. In this article, we discuss the current knowledge of the impact of PAMPs from both gut mycobiota and microbiota, including epithelial barrier function and the "gut-liver-kidney axis," on bacterial sepsis severity.

Updates in the epidemiology and management of candidemia and Clostridioides difficile coinfection

Introduction: In recent years, more and more studies have focused on the association between candidemia and Clostridioides difficile infection (CDI), highlighting the risk of subsequent candidemia in patients with CDI. However, a more recent model focuses on the Candida-Clostridioides difficile coinfection as a clinical entity in which candidemia could occur before or after the CDI episode. Areas covered: In this review we analyzed the physiopathological mechanisms underlying the Candida-Clostridioides difficile coinfection, both in case of candidemia preceding and following the CDI. We highlighted that gut alterations occurring during a CDI play a crucial role in the risk of subsequent candidemia. Moreover, we identified areas of interest about the management of Candida-Clostridioides difficile coinfection and proposed answers to relevant clinical questions. Expert opinion: The evaluation of risk factors for candidemia in patients with CDI and the rational antibiotic use in patients with candidemia remain the most efficacious and cost-free instruments to optimally manage the Candida-Clostridioides difficile coinfection. However, further studies are required to cover some unmet needs, such as the development of rapid diagnostic methods of candidemia and the use of new available drugs with minimal effect on the microbiome biodiversity in patients with CDI at high risk of fungemia.

T2Candida MR as a predictor of outcome in patients with suspected invasive candidiasis starting empirical antifungal treatment: a prospective pilot study

Objectives

We assessed the potential role of T2Candida MR (T2MR) and serological biomarkers [β-d-glucan (BDG) or Candida albicans germ tube antibodies (CAGTA)], alone or in combination with standard cultures, for identifying patients with suspected invasive candidiasis (IC), who may benefit from maintaining antifungal therapy.

Methods

Prospective observational multicentre study including all adult patients receiving empirical antifungal therapy for suspected IC, from January to June 2017. CAGTA, BDG and T2MR were determined at baseline and at +2 and +4 days after enrolment. Primary endpoint was the diagnostic value of CAGTA, BDG and T2MR, alone or in combination with standard culture, to predict diagnosis of IC and/or mortality in the first 7 days after starting antifungal therapy (poor outcome).

Results

Overall, 14/49 patients (28.6%) had a poor outcome (7 died within the first 7 days of antifungal therapy, whereas 7 ended with a diagnosis of IC). CAGTA [3/14 (21.4%) versus 8/35 (22.9%), P = 1] and BDG [8/14 (57.1%) versus 17/35 (48.6%), P = 0.75] results were similar in poor- and good-outcome patients. Conversely, a positive T2MR was associated with a higher risk of poor outcome [5/14 (35.7%) versus 0/35 (0.0%) P = 0.0001]. Specificity and positive predictive value of a positive T2MR for predicting poor outcome were both 100%, with a negative predictive value of 79.6%. After testing the combinations of biomarkers/standard cultures and T2MR/standard cultures, the combination of T2MR/standard cultures showed a high capacity to discriminate patients with poor outcome from those with good clinical evolution.

Conclusions

T2MR may be of significant utility to identify patients who may benefit from maintaining antifungal therapy.

T2 magnetic resonance for the diagnosis of bloodstream infections: charting a path forward

We discuss four studies in this issue of the Journal of Antimicrobial Chemotherapy that describe experience with T2 magnetic resonance (T2MR) nanodiagnostics for Candida and bacterial bloodstream infections, in the context of the T2MR literature. T2Candida and T2Bacteria panels use a dedicated instrument to detect amplified DNA from microbial cells directly in whole blood. T2Candida gives positive or negative results for C. albicans/C. tropicalis, C. glabrata/C. krusei, and C. parapsilosis. T2Bacteria detects Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Escherichia coli. In recent trials, T2Candida sensitivity and specificity for candidaemia were ∼90% and ∼98%, respectively. Two studies from Spanish hospitals now provide the first data on T2Candida as a prognostic tool. T2Candida was superior to cultures or serum β-d-glucan in identifying patients with complicated candidaemia, and in predicting the outcomes of empirical antifungal therapy for suspected candidiasis. In a retrospective study from US community hospitals, use of T2Candida was reported to reduce times to appropriate antifungal therapy, shorten courses of empirical therapy, and save an average of US$280 in antifungal costs per patient tested. Finally, a study from a hospital in Rome provides the first clinical data for T2Bacteria: sensitivity and specificity were 89% and 98%, respectively, among patients with positive blood cultures for bacteria detected by the panel, or fulfilling criteria for infection. We conclude that T2MR diagnostics are promising both for detecting bloodstream infections due to Candida and bacteria, and for providing prognostic information. More studies that present real-world performance data are needed.