Temporal trends, risk factors and outcomes in albicans and non-albicans candidaemia: an international epidemiological study in four multidisciplinary intensive care units

Evaluation of Systemic Antifungal Prescribing Knowledge and Practice in the Critical Care Setting among ICU Physicians and Clinical Pharmacists: A Cross-Sectional Study

Management of invasive fungal infections (IFI) and subsequent treatment choices remain challenging for physicians in the ICU. Documented evidence shows increased practice of the inappropriate use of antifungal agents in the ICU. Continuous education of healthcare providers (HCPs) represents the cornerstone requirement for starting an antifungal stewardship program (AFS). This study aimed at evaluating knowledge gaps in systemic antifungal prescribing among physicians and clinical pharmacists in a critical care setting. A cross-sectional, multi-center, survey-based study was conducted in five tertiary hospitals located in Al-Ahsaa, Saudi Arabia between January and May 2021. A self-administered questionnaire was distributed among the targeted clinicians. A total of 63 clinicians were involved (65.5% ICU physicians and 34.5% clinical pharmacists). It was noted that a minority of the participating HCPs (3.2%) had overall good knowledge about antifungal prescribing, but the majority had either moderate (46%) or poor (50.8%) knowledge. The difference in overall knowledge scores between the ICU physicians and the clinical pharmacists (p = 0.925) was not significant. However, pharmacists showed better scores for the pharmacokinetics of antifungal therapy (p = 0.05). This study has revealed a significant gap in the knowledge and practice of clinicians as regards prescribing antifungal therapy in our area. Although the results cannot be generalized, the outcome of this study has exposed the need for a tailored training program essential for carrying out an AFS program.

Comparative Analysis of Epidemiological and Clinical Characteristics Between Invasive Candida Infection versus Colonization in Critically Ill Patients in a Tertiary Hospital in Anhui, China

Objective

Invasive infections due to Candida spp. have unique epidemiology, strain distribution, antimicrobial susceptibility, and clinical features. This study aimed to compare and evaluate these characteristic variables between invasive Candida infection and colonization of critically ill patients in local China to potentially improve differential diagnosis and therapy.

Methods

A total of 193 critically ill patients were recruited and followed up for the study, and 133 Candida isolates were obtained from invasive Candida-infected or -colonized subjects. The strains were identified to species level through matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry, assisted by DNA sequencing. Candida susceptibility to common antifungals, including azoles, was determined by microbroth ATB Fungus 3 methodology. Azole resistance–related gene sequencing and homologous 3D-structure modeling were employed. Patient demographics and clinical risk factors were documented and comparatively analyzed from the hospital information-management system.

Results

Non–C. albicans Candida (56%) principally caused invasive Candida infections, while C. albicans (55.17%) contributed more to Candida colonization in critically ill patients. Additional risk factors exerted significant impact on both Candida cohorts, primarily including invasive interventions, cancers, and concurrent infections in common. Most colonized Candida spp. harbored relatively higher sensitivity to azoles. ERG11 gene mutations of T348A and A1309G, A395T and C461T, and a novel G1193T to our knowledge were identified in azole-resistant C. albicans, C. tropicalis, and C. parapsilosis respectively, and their corresponding homologous 3D-structure modeling was putatively achieved.

Conclusion

Distinct epidemiological and clinical characteristics existed between invasive Candida infection and colonization in critically ill patients. Multiple risk factors significantly involved both the Candida cohorts. Colonized Candida exhibited generally higher azole sensitivity than invasively infectious counterparts. ERG11 point mutations had mechanistically potential ties with local Candida resistance to azoles.

Candida Bloodstream Infections: Changes in Epidemiology and Increase in Drug Resistance

The literature on bloodstream infections (BSIs) have predominantly been biased towards bacteria, given their superior clinical significance in comparison with the other types of microorganisms. Fungal pathogens have epidemiologically received relatively less attention, although they constitute an important proportion of BSI aetiologies. In this review, the authors discuss the clinical relevance of fungal BSIs in the context of Candida species, as well as treatment options for the infections, emphasizing the compelling need to develop newer antifungals and strengthen antimicrobial stewardship programmes in the wake of the rapid spread of antifungal resistance.

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.

Epidemiology and Mycology of Candidaemia in non-oncological medical intensive care unit patients in a tertiary center in the United States: Overall analysis and comparison between non-COVID-19 and COVID-19 cases

The epidemiology and mycology of invasive candidiasis in the ICU is well‐described in certain types of critically ill patients but not in others. One population that has been scarcely studied is non‐neutropenic patients admitted specifically to medical ICUs. Even less is known about the broader category of medical ICU patients without active oncological disease. This group constitutes a very large share of the patients requiring critical care across the globe, especially in the era of the SARS‐CoV‐2 pandemic. We analysed medical ICU candidaemia episodes that occurred in non‐oncological patients in our tertiary academic centre in the United States from May 2014 to October 2020 to determine the incidence and species distribution of the associated isolates. We then separately considered non‐COVID‐19 and COVID‐19 cases and compared their characteristics. In the non‐COVID‐19 group, there were 38 cases for an incidence of 1.1% and rate of 11/1000 admissions. In the COVID‐19 group, there were 12 cases for an incidence of 5.1% and rate of 51/1000 admissions. In the entire sample, as well as separately in the non‐COVID‐19 and COVID‐19 groups,Candida albicans accounted for a minority of isolates. Compared to non‐COVID‐19 patients with candidaemia, COVID‐19 patients had lower ICU admission SOFA score but longer ICU length of stay and central venous catheter dwell time at candidaemia detection. This study provides valuable insight into the incidence and species distribution of candidaemia cases occurring in non‐oncological critically ill patients and identifies informative differences between non‐COVID‐19 and COVID‐19 patients.

Fungemia in COVID-19 ICU patients, a single medical center experience

A known proportion of patients who are admitted for the novel coronavirus disease 2019 (COVID-19) requires intensive care unit (ICU) level of care. Prolonged ICU stay is a risk factor for the development of nosocomial candidemia. The current study aimed to investigate the incidence and risk factors associated with the development of nosocomial candidemia among patients admitted to the ICU for COVID-19. Patients who developed nosocomial candidemia were identified, and their clinical course was reported. A 1:3 case control matching was used to identify non-candidemia patients who served as controls. 89 patients were admitted to the ICU for COVID-19 during the study period. The incidence of nosocomial candidemia was 8.9% (n = 8). Case-control matching identified 24 patients with similar disease severity at the time of ICU admission. Median time to first isolation of yeast was 26 days. Candidemia patients reported longer median ICU stay than controls. (40 vs. 10 days, p = .004). In hospital death rates were comparable in both groups (38% vs. 54%, p = .548). Prolonged mechanical ventilation support was associated with the development of nosocomial candidemia.

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.

Effect of initial antifungal therapy on mortality among patients with bloodstream infections with different Candida species and resistance to antifungal agents: A multicentre observational study by the Turkish Fungal Infections Study Group

This study aimed to describe the effect of initial antifungal therapy on patient mortality and to detail the current distribution and resistance patterns of Candida spp. among patients with candidaemia. A prospective observational study was performed among consecutive patients with candidaemia from 10 Turkish medical centres between January 2015 and November 2018. The primary outcome was 10-day mortality. Species were identified using MALDI-TOF/MS. A total of 342 patients with candidaemia were included, of which 175 (51.2%) were male and 68 (19.9%) were aged <18 years. The most common species were Candida albicans (47.4%), Candida parapsilosis (26.6%), Candida tropicalis (9.6%) and Candida glabrata (7.6%). Among all Candida spp., the 10-day case fatality rate (CFR) was 32.2%. The CFR was highest in patients with C. albicans (57.3%) and lowest in patients with C. parapsilosis (21.8%). The resistance rate to fluconazole was 13% in C. parapsilosis, with no significant effect on mortality. No resistance to echinocandins was detected. In the multivariate analysis, being in the ICU [OR = 2.1 (95% CI 1.32-3.57); P = 0.002], renal failure [OR = 2.4 (1.41-3.97); P = 0.001], total parenteral nutrition [OR = 2 (1.22-3.47); P = 0.006], C. albicans infection [OR = 1.7 (1.06-2.82); P = 0.027] and echinocandin as primary agent [OR = 0.6 (0.36-0.99); P = 0.047] were significantly associated with mortality. Candidaemia is a deadly infection. Fluconazole resistance is emerging, although it was not significantly related to mortality. Using an echinocandin as the primary agent could be life-saving.

Choosing the Right Antifungal Agent in ICU Patients

Fungi are responsible for around 20% of microbiologically documented infections in intensive care units (ICU). In the last decade, the incidence of invasive fungal infections (IFI), including candidemia, has increased steadily because of increased numbers of both immunocompromised and ICU patients. To improve the outcomes of patients with IFI, intensivists need to be aware of the inherent challenges. This narrative review summarizes the features of routinely used treatments directed against IFI in non-neutropenic ICU patients, which include three classes of antifungals: polyenes, azoles, and echinocandins. ICU patients’ pathophysiological changes are responsible for deep changes in the pharmacokinetics of antifungals. Moreover, drug interactions affect the response to antifungal treatments. Consequently, appropriate antifungal dosage is a challenge under these special conditions. Dosages should be based on renal and liver function, and serum concentrations should be monitored. This review summarizes recent guidelines, focusing on bedside management.

Polymerase Chain Reaction Versus Blood Culture to Detect Candida Species in High-Risk Patients with Suspected Invasive Candidiasis: The MICAFEM Study

INTRODUCTION

We evaluated the diagnostic reliability of serum polymerase chain reaction (PCR) versus blood culture, abdominal fluid or both (composite measure) in patients receiving empirical antifungal treatment for suspected invasive candidiasis.

METHODS

This observational, prospective, non-interventional, multicentre study in Spain enrolled 176 critically ill patients admitted to the intensive care unit. Separate blood samples for culture and serum PCR were taken before the start of antifungal therapy. Patient assessment was performed according to each site's usual clinical practice. The primary end point was concordance between serum PCR and blood culture. Secondary end points were concordance between serum PCR and a positive abdominal fluid sample or the composite measure. Quality indices included sensitivity, specificity, positive/negative predictive values (PPV/NPV) and kappa indices.

RESULTS

Among 175 evaluable patients, rates of Candida detection were similar for serum PCR (n = 16/175, 9.1%) versus blood culture (n = 14/175, 8.0%). Quality indices for serum PCR relative to blood culture were: sensitivity 21.4%; specificity 91.9%; PPV 18.8%; NPV 93.1%; kappa index 0.125. Thirty-two abdominal fluid samples were positive. Quality indices for serum PCR versus abdominal fluid were: sensitivity 31.3%; specificity 83.0%; PPV 15.6%; NPV 92.3%; kappa index 0.100. Quality indices for serum PCR versus the composite measure were: sensitivity 15.8%; specificity 92.7%; PPV 37.5%; NPV 79.9%; kappa index 0.107.

CONCLUSION

The sensitivity of serum PCR for Candida detection was low and the rate of concordance was low between serum PCR and the other diagnostic techniques used to identify Candida infections. Hospital-based diagnostic tests need optimising to improve outcomes in patients with suspected invasive candidiasis.

FUNDING

Astellas Pharma Inc.

Diagnosis and management of invasive candidiasis in the ICU: an updated approach to an old enemy

Invasive fungal infections, particularly those caused by Candida species, are not uncommon in critically ill patients and are associated with considerable morbidity and mortality. Diagnosis and management of these infections can be challenging. In this review, we will briefly discuss recent epidemiological data on invasive candidiasis and current diagnostic approaches before concentrating on antifungal treatments.

Invasive candidiasis in intensive care units in China: Risk factors and prognoses of Candida albicans and non-albicans Candida infections

BACKGROUND

To investigate the risk factors and prognoses of patients with invasive Candida albicans and non-albicans Candida (NAC) infection in intensive care units (ICUs) in China.

METHODS

Between November 2009 and April 2011, we performed a prospective study of critically ill patients with invasive Candida infection from 67 ICUs across China to compare the risk factors and mortality between patients with C albicans and NAC infection.

RESULTS

There were 306 patients with proven invasive Candida; 244 cases (a total 389 Candida isolates) were sent to laboratory for strain identification (C albicans, 40.1%; NAC, 59.9%). More patients admitted for surgery or trauma had NAC infection than C albicans infection. C albicans infection was more common in patients with subclavian vein catheters or peritoneal drainage tubes. Compared with patients with C albicans infection, patients with NAC infection had longer antifungal therapy (P < .001), longer ICU (P = .004) or hospital stay (P = .002), and slightly higher mortality (38.4% vs 29.6%), but the difference was not significant (P = .17).

CONCLUSIONS

C albicans remains the most common pathogen in candidiasis in critical care patients. However, the number of NAC infections exceeded C albicans infections. Compared with patients with C albicans infection, patients with NAC infection had heavier disease burdens.

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 and risk factors for nosocomial Non-Candida albicans candidemia in adult patients at a tertiary care hospital in North China

Nosocomial candidemia extends the length of hospital stay, increases the costs of medical care, and is associated with a high mortality rate. Epidemiological data that assist in the choice of initial therapy may help to improve the prognosis. The present study was undertaken to investigate the epidemiology of nosocomial candidemia and identify risk factors for nosocomial candidemia caused by C. albicans and non-albicans Candida species (NAC). A retrospective chart review was undertaken to analyze cases of nosocomial candidemia treated at the Beijing Friendship Hospital between January 2008 and December 2012. All cases of candidemia were identified using the previously published criteria. Among 106 patients analyzed, 53.8% had nosocomial candidemia caused by NAC. Candida albicans was the most common causative agent, accounting for 46.2% of all cases, followed by C. glabrata (25.5%), C. tropicalis (15.1%), C. parapsilosis (10.4%) and C. Krusei (0.9%). Comparison of nosocomial C. albicans and NAC candidemia by multivariate logistic regression showed that factors independently associated with nosocomial NAC candidemia included exposure to azole agents (odds ratio [OR]: 3.359; 95% confidence interval [CI]: 1.136-10.154; P = .031) and artificial surgical implants (OR: 37.519; 95% CI: 2.5-562.998; P = .009). A significant risk factor for nosocomial C. albicans candidemia was cancer surgery (OR: 0.075; 95% CI: 0.013-0.437; P = .004). Clinical and epidemiological differences in the risk factors between nosocomial candidemia caused by C. albicans and NAC should be considered when selecting an initial antifungal regimen for the treatment of adult patients. This should be undertaken before the availability of species identification and/or antifungal susceptibility results.

Pharmacokinetic variability and exposures of fluconazole, anidulafungin, and caspofungin in intensive care unit patients: Data from multinational Defining Antibiotic Levels in Intensive care unit (DALI) patients Study

Introduction

The objective of the study was to describe the pharmacokinetics (PK) of fluconazole, anidulafungin, and caspofungin in critically ill patients and to compare with previously published data. We also sought to determine whether contemporary fluconazole doses achieved PK/pharmacodynamic (PD; PK/PD) targets in this cohort of intensive care unit patients.

Methods

The Defining Antibiotic Levels in Intensive care unit patients (DALI) study was a prospective, multicenter point-prevalence PK study. Sixty-eight intensive care units across Europe participated. Inclusion criteria were met by critically ill patients administered fluconazole (n = 15), anidulafungin (n = 9), and caspofungin (n = 7). Three blood samples (peak, mid-dose, and trough) were collected for PK/PD analysis. PK analysis was performed by using a noncompartmental approach.

Results

The mean age, weight, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores of the included patients were 58 years, 84 kg, and 22, respectively. Fluconazole, caspofungin, and anidulafungin showed large interindividual variability in this study. In patients receiving fluconazole, 33% did not attain the PK/PD target, ratio of free drug area under the concentration-time curve from 0 to 24 hours to minimum inhibitory concentration (fAUC_0–24/MIC) ≥100. The fluconazole dose, described in milligrams per kilogram, was found to be significantly associated with achievement of fAUC_0–24/MIC ≥100 (P = 0.0003).

Conclusions

Considerable interindividual variability was observed for fluconazole, anidulafungin, and caspofungin. A large proportion of the patients (33%) receiving fluconazole did not attain the PK/PD target, which might be related to inadequate dosing. For anidulafungin and caspofungin, dose optimization also appears necessary to minimize variability.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0758-3) contains supplementary material, which is available to authorized users.

Single-center retrospective study of the incidence of, and risk factors for, non-C. albicans invasive candidiasis in hospitalized patients in China

The aims of this study were to establish the incidence of invasive candidiasis (IC) in a Beijing hospital, to identify risk factors associated with IC caused by non-C. albicans Candida (NAC), and to determine risk factors for infection caused by NAC species not susceptible to fluconazole. Clinical data from 141 patients admitted to Beijing Chaoyang Hospital (from 2001-2010) diagnosed with IC were retrospectively analyzed. The incidence of IC increased during the 10-year period, but the proportion due to NAC did not change significantly in that of 141 cases, 55 (39%) were due to NAC and 86 (61%) to C. albicans (CA). The NAC species isolated included C. tropicalis (25 of 141, 18%), C. glabrata (14 of 141, 9.9%), C. parapsilosis (eight of 141, 5.7%), C. krusei (three of 141, 2.1%) and C. lusitaniae (one of 141, 0.71%); other Candida species accounted for four of the 141 cases (2.8%). Twenty-one isolates (38%) of NAC were not susceptible to fluconazole. Total parenteral nutrition (TPN) (OR 4.2; 95% CI 3.5-58; P < 0.001) and previous fluconazole therapy (OR 7.7; 95% CI 2.2-27; P = 0.001) were risk factors for invasive NAC candidiasis, whereas patient age ≥65 years (OR 0.37; CI 0.16-0.88; P = 0.025) and invasive mechanical ventilation (OR 0.22; CI 0.069-0.70; P =0.010) were connected with invasive CA candidiasis. Prior fluconazole therapy was a risk factor (P = 0.007) for infections caused by NAC not susceptible to fluconazole. In conclusion, TPN and prior fluconazole therapy are independent risk factors for NAC infection, while prior fluconazole therapy is a risk factor for infection due to NAC not susceptible to fluconazole.

Yeast central nervous system infection in a critically ill patient: a case report

Introduction

Invasive fungal infections are alarmingly common in intensive care unit patients; invasive fungal infections are associated with increased morbidity and mortality. Risk factors are the increased use of indwelling central venous catheters, the use of broad spectrum antibiotics, parenteral nutrition, renal replacement therapy and immunosuppression. Diagnosis of these infections might be complicated, requiring tissue cultures. In addition, therapy of invasive fungal infections might be difficult, given the rising resistance of fungi to antifungal agents.

Case presentation

We describe the case of a 28-year-old Greek man with yeast central nervous system infection.

Conclusions

Difficult-to-treat fungal infections may complicate the clinical course of critically ill patients and render their prognosis unfavorable. This report presents a case that was rare and difficult to treat, along with a thorough review of the investigation and treatment of these kinds of fungal infections in critically ill patients.

How to select an antifungal agent in critically ill patients

Fungal infections are common in critically ill patients and are associated with increased morbidity and mortality. Candida spp are the most commonly isolated fungal pathogens. The last 2 decades have seen an increased incidence of fungal infections in critical illness and the emergence of new pathogenic fungal species and also the development of more effective (better bioavailability) and safer (less toxicity, fewer drug interactions) drugs. The distinction between colonization and infection can be difficult, and problems diagnosing infection may delay initiation of antifungal treatment. A number of factors have been identified that can help to distinguish patients at high risk for fungal infection. The antifungal agents that are most frequently used in the intensive care unit are the first- and second-generation azoles and the echinocandins; amphotericin B derivatives (mainly the liposomal agents) are less widely used because of adverse effects. The choice of antifungal agent in critically ill patients will depend on the aim of therapy (prophylaxis, pre-emptive, empiric, definitive), as well as on local epidemiology and specific properties of the drug (antifungal spectrum, efficacy, toxicity, pharmacokinetic/pharmacodynamic properties, cost). In this article we will review all these aspects and propose an algorithm to guide selection of antifungal agents in critically ill patients.

Mouse model of invasive fungal infection

The mouse intravenous (IV) challenge model of Candida albicans invasive fungal infection has been widely used to study the importance of the innate immune system in these infections. This chapter describes this well-characterized model, where fungal cells are administered directly into the mouse bloodstream to initiate a systemic infection. The preparation of tissue samples from infected mice to allow evaluation of disease progression and host responses is also described.

Predictors and outcomes of Candida bloodstream infection: eight-year surveillance, western Saudi Arabia

OBJECTIVES

To assess the epidemiological pattern of Candida bloodstream infection (BSI) over an 8-year period (2002-2009) in King Abdulaziz Medical City, western Saudi Arabia.

METHOD

A retrospective chart review was performed.

RESULTS

A total of 258 BSI were identified in 134 males (53.2%) and 118 females (46.8%). There were 86 (34.1%) cases of Candida albicans and 166 (65.9%) non-albicans Candida species. Malignancy was independently associated with the development of candidemia by non-albicans Candida species (odds ratio 3.24, 95% confidence interval 1.25-8.41). Fluconazole in vitro susceptibility was 38.5% for C. albicans and 52.5% for other Candida species. The overall, crude 12-month mortality rate was 50% for C. albicans and 57.8% for non-albicans Candida species.

CONCLUSIONS

The antifungal resistance coinciding with a change in the epidemiologic pattern of candidemia identified in this study is alarming and urges the need for a review of empiric antifungal therapy and potential contributing environmental factors.

Systemic Infection Due to Candida parapsilosis in a Domestic Ferret (Mustela putorius furo)

An 18-month-old castrated male ferret (Mustela putorius furo) was presented to the veterinary hospital for acute collapse but died despite initiation of emergency treatment. The body was submitted for a complete postmortem examination. The pathologist determined the ferret was suffering from severe necrotizing encephalitis, necrogranulomatous mediastinal lymphadenitis, and ulcerative dermatitis attributable to systemic Candida parapsilosis. This is the first report of systemic Candida parapsilosis in a ferret.

Hemolytic factor production by clinical isolates of Candida species

Most cases of fungal bloodstream infections (BIs) are attributed to Candida albicans; however, non-Candida albicans Candida species have recently been identified as common pathogens. Although hemolytic factor is known to be putative virulence factor contributing to pathogenicity in Candida species, its production is poorly evaluated. The present study was undertaken to analyze the production of hemolytic factor by C. albicans (10), C. tropicalis (13), and C. parapsilosis (8) isolates associated with BIs. Data of hemolysis zones on plate assay revealed that the majority of C. albicans isolates produced mild hemolytic activity whereas the majority of C. tropicalis produced strong activity. None of the tested C. parapsilosis isolates exhibited hemolysis on plate assay. We also evaluated the hemolytic activity in the cell-free broth. There were no significant differences (P > 0.05) in the secreted hemolytic activity among intra-species isolates. Different levels of secreted hemolytic factor were observed for Candida species, where C. tropicalis exhibited the highest production of hemolytic factor (P < 0.05) followed by C. albicans and C. parapsilosis. Inhibition of hemolysis (up to 89.12 %) from culture supernatant, following incubation with the lectin Concanavalin A (Con A), was observed for all three Candida species. This finding suggests that the secreted hemolytic factor of C. tropicalis and C. parapsilosis may be a mannoprotein, similar to that described for C. albicans.

Invasive candidiasis in intensive care units in China: in vitro antifungal susceptibility in the China-SCAN study

OBJECTIVES

The objectives of this study were to determine species distribution and in vitro antifungal susceptibility of Candida isolates identified in the multicentre China-SCAN study of invasive Candida infection (ICI) in intensive care units (ICUs) across China.

METHODS

Candida isolates from patients in the China-SCAN study with documented ICI were evaluated by a central laboratory. Species were identified using chromogenic culture media or the API 20C AUX kit. Susceptibility to fluconazole, voriconazole, itraconazole, caspofungin and amphotericin B was determined using the CLSI broth microdilution method (M27-A3) and updated clinical breakpoints or epidemiological cut-off values.

RESULTS

A total of 389 isolates from 244 patients were analysed. Species identified most frequently were Candida albicans (40.1%), Candida parapsilosis (21.3%), Candida tropicalis (17.2%) and Candida glabrata (12.9%). Rarer species such as Lodderomyces elongisporus and Candida ernobii were also identified. Fluconazole susceptibility was evident in 85.9% (134/156) of C. albicans, 62.7% (42/67) of C. tropicalis and 48.2% (40/83) of C. parapsilosis isolates. Susceptibility to voriconazole was ≥ 90% among all species. All isolates were susceptible to amphotericin B and caspofungin except C. glabrata [86.0% (43/50) susceptible to caspofungin]. Cross-resistance between fluconazole and voriconazole was observed for C. parapsilosis and C. glabrata.

CONCLUSIONS

Although C. albicans was the predominant single species, non-albicans species constituted >50% of isolates. Fluconazole susceptibility was lower in most non-albicans species, indicating that fluconazole resistance should be closely monitored. Susceptibility to voriconazole, amphotericin B and caspofungin is encouraging. Differences between these data and those from other regions emphasize the importance of assessing regional variations.

Invasive candidiasis as a cause of sepsis in the critically ill patient

Invasive fungal infections are an increasingly frequent etiology of sepsis in critically ill patients causing substantial morbidity and mortality. Candida species are by far the predominant agent of fungal sepsis accounting for 10% to 15% of health-care associated infections, about 5% of all cases of severe sepsis and septic shock and are the fourth most common bloodstream isolates in the United States. One-third of all episodes of candidemia occur in the intensive care setting. Early diagnosis of invasive candidiasis is critical in order to initiate antifungal agents promptly. Delay in the administration of appropriate therapy increases mortality. Unfortunately, risk factors, clinical and radiological manifestations are quite unspecific and conventional culture methods are suboptimal. Non-culture based methods (such as mannan, anti-mannan, β-d-glucan, and polymerase chain reaction) have emerged but remain investigational or require additional testing in the ICU setting. Few prophylactic or pre-emptive studies have been performed in critically ill patients. They tended to be underpowered and their clinical usefulness remains to be established under most circumstances. The antifungal armamentarium has expanded considerably with the advent of lipid formulations of amphotericin B, the newest triazoles and the echinocandins. Clinical trials have shown that the triazoles and echinocandins are efficacious and well tolerated antifungal therapies. Clinical practice guidelines for the management of invasive candidiasis have been published by the European Society for Clinical Microbiology and Infectious Diseases and the Infectious Diseases Society of North America.

Occurrence, presentation and treatment of candidemia

Candida is one of the most common causes of nosocomial bloodstream infections. Candidemia is not confined to hematological patients, intensive care units or abdominal surgery wards, but it is remarkably frequent in the internal medicine setting. High mortality associated with candidemia can be reduced by prompt, appropriate antifungal therapy. The epidemiology of species has been shifting toward non-albicans strains. Significant improvements in nonculture-based diagnostic methods, such as serological markers, have been made in recent years, and novel diagnostic techniques should be further studied to enable early pre-emptive therapy. Treatment guidelines indicate that echinocandins are at present the best choice for patients who are severely ill or possibly infected with fluconazole-resistant strains.

Invasive fungal infections in patients with cancer in the Intensive Care Unit

Invasive fungal infections (IFIs) have emerged as a major cause of morbidity and mortality amongst critically ill patients. Cancer patients admitted to the Intensive Care Unit (ICU) have multiple risk factors for IFIs. The vast majority of IFIs in the ICU are due to Candida spp. The incidence of invasive candidiasis (IC) has increased over recent decades, especially in the ICU. A shift in the distribution of Candida spp. from Candida albicans to non-albicans Candida spp. has been observed both in ICUs and oncology units in the last two decades. Timely diagnosis of IC remains a challenge despite the introduction of new microbiology techniques. Delayed initiation of antifungal therapy is associated with increased mortality. Therefore, prediction rules have been developed and validated prospectively in order to identify those ICU patients at high risk for IC and likely to benefit from early treatment. These rules, however, have not been validated in cancer patients. Similarly, major clinical studies on the efficacy of newer antifungals typically do not include cancer patients. Despite the introduction of more potent and less toxic antifungals, mortality from IFIs amongst cancer patients remains high. In recent years, aspergillosis and mucormycosis have also emerged as significant causes of morbidity and mortality amongst ICU patients with haematological cancer.

Impact of yeast-bacteria coinfection on the detection of Candida sp. in an automated blood culture system

Invasive candidiasis remains a major cause of morbidity and mortality. It is now well known that an early diagnosis contributes to the patients' outcome. Blood cultures, which are the first-line test in case of bloodstream infection suspicion, can be carried out using fungus-selective medium (containing antibiotics) or standard microorganism medium allowing both bacterial and fungal growth. Some patients can suffer from polymicrobial sepsis involving bacteria and yeasts, so we decided to investigate in blood cultures the influence of the presence of bacteria on fungal development. Simulated blood cultures were performed using Candida albicans or C. glabrata coincubated with Escherichia coli or Staphylococcus aureus at different concentrations. The results showed that, in a standard microorganism medium, bacterial growth could hide the fungal development. Thus, in patients at risk of invasive candidiasis, the use of a specific fungal medium could improve the diagnosis and allow an earlier efficient antifungal treatment.

The rising problem of antimicrobial resistance in the intensive care unit

Mainly due to its extremely vulnerable population of critically ill patients, and the high use of (invasive) procedures, the intensive care unit (ICU) is the epicenter of infections. These infections are associated with an important rise in morbidity, mortality, and healthcare costs. The additional problem of multidrug-resistant pathogens boosts the adverse impact of infections in ICUs. Several factors influence the rapid spread of multidrug-resistant pathogens in the ICU, e.g., new mutations, selection of resistant strains, and suboptimal infection control. Among gram-positive organisms, the most important resistant microorganisms in the ICU are currently methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci. In gram-negative bacteria, the resistance is mainly due to the rapid increase of extended-spectrum Beta-lactamases (ESBLs) in Klebsiella pneumonia, Escherichia coli, and Proteus species and high level third-generation cephalosporin Beta-lactamase resistance among Enterobacter spp. and Citrobacter spp., and multidrug resistance in Pseudomonas aeruginosa and Acinetobacter species. To conclude, additional efforts are needed in the future to slow down the emergence of antimicrobial resistance. Constant evaluation of current practice on basis of trends in MDR and antibiotic consumption patterns is essential to make progress in this problematic matter.

The effect of diabetes on mortality in critically ill patients: a systematic review and meta-analysis

Introduction

Critically ill patients with diabetes are at increased risk for the development of complications, but the impact of diabetes on mortality is unclear. We conducted a systematic review and meta-analysis to determine the effect of diabetes on mortality in critically ill patients, making a distinction between different ICU types.

Methods

We performed an electronic search of MEDLINE and Embase for studies published from May 2005 to May 2010 that reported the mortality of adult ICU patients. Two reviewers independently screened the resultant 3,220 publications for information regarding ICU, in-hospital or 30-day mortality of patients with or without diabetes. The number of deaths among patients with or without diabetes and/or mortality risk associated with diabetes was extracted. When only crude survival data were provided, odds ratios (ORs) and standard errors were calculated. Data were synthesized using inverse variance with ORs as the effect measure. A random effects model was used because of anticipated heterogeneity.

Results

We included 141 studies comprising 12,489,574 patients, including 2,705,624 deaths (21.7%). Of these patients, at least 2,327,178 (18.6%) had diabetes. Overall, no association between the presence of diabetes and mortality risk was found. Analysis by ICU type revealed a significant disadvantage for patients with diabetes for all mortality definitions when admitted to the surgical ICU (ICU mortality: OR [95% confidence interval] 1.48 [1.04 to 2.11]; in-hospital mortality: 1.59 [1.28 to 1.97]; 30-day mortality: 1.62 [1.13 to 2.34]). In medical and mixed ICUs, no effect of diabetes on all outcomes was found. Sensitivity analysis showed that the disadvantage in the diabetic surgical population was attributable to cardiac surgery patients (1.77 [1.45 to 2.16], P < 0.00001) and not to general surgery patients (1.21 [0.96 to 1.53], P = 0.11).

Conclusions

Our meta-analysis shows that diabetes is not associated with increased mortality risk in any ICU population except cardiac surgery patients.

Pharmacokinetic evaluation of fluconazole in critically ill patients

INTRODUCTION

Invasive candidiasis has emerged over the last few decades as an increasingly important nosocomial problem for the critically ill, affecting around 2% of intensive care unit patients. Although poor outcomes associated with invasive candidiasis among critically ill patients may relate to severe underlying disease processes and delayed institution of antifungal therapy, inadequate dosing of antifungal agents may also contribute.

AREAS COVERED

This drug evaluation provides a critical appraisal of the published literature pertaining to the pharmacokinetics of fluconazole in critically ill, obese or severely burned patients, including those receiving acute renal replacement therapy. The pharmacodynamics of fluconazole is also covered, as well as the likely clinical implications for optimal dosing and the toxicity of fluconazole. Last, variations in fluconazole susceptibility patterns of Candida spp. are also discussed.

EXPERT OPINION

Recently, there has been an increased but geographically variable prevalence of non-albicans Candida spp., causing invasive candidiasis and an overall trend towards reduced fluconazole susceptibility. The pathophysiological changes of critical illness, coupled with a lack of dose finding studies, support the use of local susceptibility patterns to guide fluconazole dosing until such time as pharmacokinetic-pharmacodynamic information to guide optimal fluconazole dosing strategies and pharmacodynamic targets becomes available.

[Guidelines for the treatment of Invasive Candidiasis and other yeasts. Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). 2010 Update]

These guidelines are an update of the recommendations of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) that were issued in 2004 (Enferm Infecc Microbiol Clin. 2004, 22:32-9) on the treatment of Invasive Candidiasis and infections produced by other yeasts. This 2010 update includes a comprehensive review of the new drugs that have appeared in recent years, as well as the levels of evidence for recommending them. These guidelines have been developed following the rules of the SEIMC by a working group composed of specialists in infectious diseases, clinical microbiology, critical care medicine, paediatrics and oncology-haematology. It provides a series of general recommendations regarding the management of invasive candidiasis and other yeast infections, as well as specific guidelines for prophylaxis and treatment, which have been divided into four sections: oncology-haematology, solid organ transplantation recipients, critical patients, and paediatric patients.

Epidemiology of invasive candidiasis

PURPOSE OF REVIEW

This review covers candidaemia in numbers, susceptibility issues, host groups, risk factors and outcome.

RECENT FINDINGS

The incidence of candidaemia has increased over the last decades. Candida glabrata is particularly common in the northern hemisphere and with increasing age whilst the opposite is true for C. parapsilosis, C. glabrata, C. krusei and a number of emerging species are not fully susceptible to azoles. C. parapsilosis and C. guilliermondii are not fully susceptible to echinocandins. Increasing rates of C. parapsilosis have been observed at centres with a high use of echinocandins, and outcome for this species is not superior comparing echinocandins with fluconazole. Acquired azole resistance has recently been described in as many as a third of 19% resistant isolates and echinocandin resistance has emerged and been detected as early as day 12 of echinocandin therapy. ICU stay and abdominal surgery are among the most important risk factors. Outcome is dependent on species involved, timing, dosing and choice of therapy and management of the primary focus of infection. However, host factors are dominating predictors of mortality in recent studies of ICU candidiasis.

SUMMARY

The changing epidemiology highlights the need for close monitoring of local incidence, species distribution and susceptibility in order to optimize therapy and outcome.

Epidemiology and risk factors for non-Candida albicans candidemia in non-neutropenic patients at a Chinese teaching hospital

The purpose of this study was to describe the epidemiology of nosocomial candidemia and identify risk factors involved in infections caused by non-C. albicans Candida species in a Chinese tertiary care center over a 10-year period. A total of 102 cases of nosocomial candidemia in non-neutropenic patients admitted from 1998 through 2007 were included in the study. Candida albicans remained the most common causative agent, accounting for 57.8% of all cases, followed by C. tropicalis (12.8%), C. parapsilosis (10.8%) and C. glabrata (10.8%). Comparison of C. albicans and non-C. albicans candidemia by multivariate logistic regression showed that factors independently associated with non-C. albicans candidemia included head trauma (OR, 5.34; 95% CI, 1.18-24.17; P = 0.029) and bacterial sepsis (OR, 3.58; 95% CI, 1.17-10.98; P = 0.026). Factors independently associated with C. albicans candidemia included tracheal intubation (OR, 0.26; 95% CI, 0.08-0.92; P = 0.037), and increased peripheral WBC count (OR, 0.84; 95% CI, 0.74-0.95; P = 0.006).

Comparison of albicans vs. non-albicans candidemia in French intensive care units

Introduction

Candidemia raises numerous therapeutic issues for intensive care physicians. Epidemiological data that could guide the choice of initial therapy are still required. This analysis sought to compare the characteristics of intensive care unit (ICU) patients with candidemia due to non-albicans Candida species with those of ICU patients with candidemia due to Candida albicans.

Methods

A prospective, observational, multicenter, French study was conducted from October 2005 to May 2006. Patients exhibiting candidemia developed during ICU stay and exclusively due either to one or more non-albicans Candida species or to C. albicans were selected. The data collected included patient characteristics on ICU admission and at the onset of candidemia.

Results

Among the 136 patients analyzed, 78 (57.4%) had candidemia caused by C. albicans. These patients had earlier onset of infection (11.1 ± 14.2 days after ICU admission vs. 17.4 ± 17.7, p = 0.02), higher severity scores on ICU admission (SOFA: 10.4 ± 4.7 vs. 8.6 ± 4.6, p = 0.03; SAPS II: 57.4 ± 22.8 vs. 48.7 ± 15.5, P = 0.015), and were less often neutropenic (2.6% vs. 12%, p = 0.04) than patients with candidemia due to non-albicans Candida species.

Conclusions

Although patients infected with Candida albicans differed from patients infected with non-albicans Candida species for a few characteristics, no clinical factor appeared pertinent enough to guide the choice of empirical antifungal therapy in ICU.

Effect of antifungal therapy timing on mortality in cancer patients with candidemia

Prior studies have shown that delays in treatment are associated with increased mortality in patients with candidemia. The purpose of this study was to measure three separate time periods comprising the diagnosis and treatment of candidemia and to determine which one(s) is associated with hospital mortality. Patients with blood cultures positive for Candida spp. were identified. Subjects were excluded if no antifungal therapy was given or if there was preexisting antifungal therapy. Collected data included the time from blood culture collection to positivity (incubation period), the time from blood culture positivity to provider notification (provider notification period), and the time from provider notification to the first dose of antifungal given (antifungal initiation period). These times were assessed as predictors of inpatient mortality. A repeat analysis was done with adjustments for age, sex, race, underlying cancer, catheter removal, APACHE III score, acute renal failure, neutropenia, and non-Candida albicans species. A total of 106 episodes of candidemia were analyzed. The median incubation time was 32.1 h and was associated with mortality (univariate hazard ratio per hour, 1.025; P = 0.001). The median provider notification and antifungal initiation periods were 0.3 and 7.5 h, respectively, and were not associated with mortality. Adjusted analysis yielded similar results. For cancer patients with candidemia, the incubation period accounts for a significant amount of time, compared with the provider notification and antifungal initiation times, and is associated with in-hospital mortality. Strategies to shorten the incubation time, such as utilizing rapid molecularly based diagnostic methods, may help reduce in-hospital mortality.

Approach to the febrile patient in the ICU

Fever is a normal adaptive brain response to infectious and noninfectious causes involving a cytokine-mediated response, the generation of acute phase reactants, and the activation of numerous physiologic, endocrinologic and immunologic systems. Ninety percent of patients with severe sepsis in the intensive care unit (ICU) will experience fever during their hospitalization, while the half of the new detected febrile episodes are of noninfectious origin. In the ICU, fever should be treated in cardiorespiratory and neurosurgical patients and in those in whom temperature exceeds 40 degrees C (104 degrees F). Antipyretic therapy must be justified regardless of the metabolic cost (if fever exceeds its physiologic benefit), the result (if the symptomatic relief adversely affects the course of the febrile illness) and the side effects.