Nosocomial candidemia; risk factors and prognosis revisited; 11 years experience from a Norwegian secondary hospital

Epidemiology of nosocomial candidemia, mortality and antifungal resistance, 7-year experience, in Turkey

Candidemia is an important clinical condition that prolongs the period of hospitalization and increases morbidity, mortality, and hospital costs. In this retrospective study, we aimed to evaluate the epidemiological and microbiological characteristics of patients with candidemia, between January 2013 and December 2019. Two hundred forty-one candidemia episodes were observed in the 230 patients, of whom 45% were female. The median age was 63 and 53.9% of the episodes were in the ICU. Frequently observed predisposing factors for candidemia included the use of antibiotics (71.3%), urinary catheterization (56.3%), Central venous catheter placement (50.3%), total parenteral nutrition (47.9%), solid-organ malignancy (46%), a surgical intervention (48.6%), chemotherapy (37%), steroid treatment (25.5%). The crude mortality rate was 52.7%. A significant difference was found between survivors and non-survivors (p = 0.007) with the Charlson comorbidity index. However, no statistically significant association was found between mortality and age, sex, surgical intervention, catheter-related candidemia, or Candida spp. The most frequently isolated Candida spp. was C. albicans (51%). Overall resistance to fluconazole, voriconazole, caspofungin, micafungin and flucytosine was 3.7%, 0%, 2.5%, 1.8%,1.8%, respectively. Consequently, there is a need for tests that yield higher success rates and rapid in diagnosis candidemia and local epidemiological data for antifungal resistance.

Candidemia in hospitalized cirrhotic patients with bloodstream infection: A retrospective analysis and brief summary of published studies

BACKGROUND

Candidemia is a life-threatening condition; however, the predictive markers for candidemia and mortality are inadequate in cirrhotic patients. This study was conducted to propose candidate predictors for the occurrence of candidemia and 30-day mortality in hospitalized cirrhotic patients with bloodstream infection (BSI) and review the related literature.

METHODS

Cirrhotic patients with BSI between January 2011 and March 2020 were screened from the databank of a medical center and eligible patients were enrolled. Patients were separated into candidemia and bacteremia groups according to the results of blood cultures. Baseline characteristics, clinical presentation, and biochemistry data were collected at this time, as were microbiological data, medical management, use of antimicrobial agents, and outcome of the patients. The parameters and 30-day mortality were compared between candidemia and bacteremia groups. A combination of the MeSH terms and text terms related to candidemia and cirrhosis was searched in the electronic databases.

RESULTS

Four hundred and sixty cirrhotic patients with BSI were enrolled. Thirty-five patients with candidemia (7.6%) were identified. Nosocomial infection, intensive care unit (ICU) admission, antibiotics exposure ≥14 days, white cell count >10 K/mm3, and model for end-stage liver disease (MELD) score >24 were associated with candidemia. The 30-day mortality was 65.7% in the candidemia group and 37.9% in the bacteremia group (p = 0.001). Nosocomial infection, ICU admission, hepatoma, hepatic encephalopathy, international normalized ratio ≥1.2, platelet ≤150 K/mm3, estimated glomerular filtration rate <60 mL/min/1.73m2, and MELD score >24 were associated with 30-day mortality. Six studies were identified. The results were consistent with our findings regarding low incidence of candidemia, and relevant risk factors are listed.

CONCLUSION

Candidemia had low incidence but high mortality in hospitalized cirrhotic patients with BSI. New predictors were proposed for the occurrence of candidemia and 30-day mortality in these patients.

Epidemiology of Candidemia: Three-Year Results from a Croatian Tertiary Care Hospital

Invasive candidosis is the most common invasive fungal infection in hospitalized patients and is associated with a high mortality rate. This is the first study from a Croatian tertiary care hospital describing epidemiology, risk factors and species distribution in patients with candidemia. A three-year retrospective observational study, from 2018 to 2020, was performed at the University Hospital Centre Zagreb, Zagreb, Croatia. A total of 160 patients with candidemia (n = 170 isolates) were enrolled. Candidemia incidence increased from 0.47 to 0.69 per 1000 admissions in 2018 and 2020, respectively. Ninety-five patients (58.38%) were in the intensive care unit. The main risk factors for candidemia were central venous catheter (CVC) (84.38%), previous surgical procedure (56.88%) and invasive mechanical ventilation (42.50%). Candida albicans was identified in 43.53% of isolates, followed by C. parapsilosis (31.76%) and C. glabrata (12.36%), C. krusei (5.29%), C. tropicalis (2.35%) and C. lusitaniae (2.35%). The study discovered a shift to non-albicansCandida species, particularly C. parapsilosis, and made it possible to determine the main tasks we should focus on to prevent candidemia in the hospital, these being mainly infection control measures directed towards prevention of catheter-related bloodstream infections, specifically comprising hand hygiene and CVC bundles of care. The potential benefit of fluconazole prophylaxis in certain populations of surgical patients could also be considered.

Preparation and In Vitro Evaluation of Alginate Microparticles Containing Amphotericin B for the Treatment of Candida Infections

Invasive candidiasis (IC) remains as a major cause of morbidity and mortality in critically ill patients. Amphotericin B (AmB) is one of the most effective antifungal agents commonly used to treat this infection. However, it induces severe side effects such as nephrotoxicity, cardiac alterations, nausea, fever, and liver damage. The utilization of drug delivery systems has been explored to overcome these limitations. Several AmB lipid formulations have been developed and are currently available in the market. Although they have the ability to reduce the main side effects of free AmB, their high cost, necessity of repeated intravenous injections for successful treatment, and incidence of pulmonary toxicity have limited their use. In the last decades, alginate has gained significant interest in drug delivery applications as a cost-effective strategy to improve the safety and therapeutic effect of toxic drugs. In this work, the clinically relevant drug AmB was encapsulated into alginate microparticles using the emulsification/external gelation method. We hypothesize that this synthesis strategy may positively impact the antifungal efficacy of AmB-loaded MCPs toward Candida albicans cells while reducing the toxicity in human lung cells. To prove this hypothesis, the ability of the microplatform to disrupt the cellular membrane potential was tested and its antifungal effectiveness toward Candida albicans cells was evaluated using the cell counting and plate count methods. Moreover, the toxicity of the microplatform in human lung cells was evaluated using CellTiter 96® AQueous cell viability assay and qualitative diffusion analysis of acridine orange. Our results demonstrated that the platform developed in this work was able to induce antifungal toxicity against Candida albicans yeast cells at the same level of free AmB with minimal toxicity to lung cells, which is one of the main side effects induced by commercial drug delivery systems containing AmB. Overall, our data provides convincing evidence about the effectiveness of the alginate-based microplatform toward Candida albicans cells. In addition, this vehicle may not require several infusions for a successful treatment while reducing the pulmonary toxic effect induced by commercial lipid formulations.

Prevalence and Antifungal Susceptibility of Pathogenic Yeasts in China: A 10-Year Retrospective Study in a Teaching Hospital

To determine the dynamic changes of pathogenic yeast prevalence and antifungal susceptibility patterns in tertiary hospitals in China, we analyzed 527 yeast isolates preserved in the Research Center for Medical Mycology at Peking University, Beijing, China, between Jan 2010 and Dec 2019 and correctly identified 19 yeast species by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and ribosomal DNA sequencing. Antifungal susceptibility testing was performed following a Sensititre YeastOne colorimetric microdilution panel with nine clinically available antifungals. The Clinical and Laboratory Standards Institute (CLSI)-approved standard M27-A3 (S4) and newly revised clinical breakpoints or species-specific and method-specific epidemiological cutoff values were used for the interpretation of susceptibility test data. In this study, although Candida albicans was the predominant single species, non-C. albicans species constituted >50% of isolates in 6 out of 10 years, and more rare species were present in the recent 5 years. The non-C. albicans species identified most frequently were Candida parapsilosis sensu stricto, Candida tropicalis, and Candida glabrata. The prevalence of fluconazole and voriconazole resistance in the C. parapsilosis sensu stricto population was <3%, but C. tropicalis exhibited decreased susceptibility to fluconazole (42, 57.5%) and voriconazole (31, 42.5%), and 22 (30.1%) C. tropicalis isolates exhibited wild-type minimum inhibitory concentrations (MICs) to posaconazole. Furthermore, fluconazole and voriconazole cross-resistance prevalence in C. tropicalis was 19 (26.1%). The overall prevalence of fluconazole resistance in the C. glabrata population was 14 (26.9%), and prevalence of isolates exhibiting voriconazole non-wild-type MICs was 33 (63.5%). High-level echinocandin resistance was mainly observed in C. glabrata, and the prevalence rates of isolate resistance to anidulafungin, micafungin, and caspofungin were 5 (9.6%), 5 (9.6%), and 4 (7.7%), respectively. Moreover, one C. glabrata isolate showed multidrug resistant to azoles, echinocandins, and flucytosine. Overall, the 10-year surveillance study showed the increasing prevalence of non-C. albicans species over time; the emergence of azole resistance in C. tropicalis and multidrug resistance in C. glabrata over the years reinforced the need for epidemiological surveillance and monitoring.

Risk factors for noncatheter-related Candida bloodstream infections in intensive care units: A multicenter case-control study

Candida bloodstream infections are associated with high mortality among critically ill patients in intensive care units (ICUs). Studies that explore the risk factors for candidemia may support better patient care in intensive care units. We conducted a retrospective, multicenter case-control study to investigate the risk factors for noncatheter-related Candida bloodstream infections (CBSI) in adult ICUs. Participants selected controls randomly on a 1:1 basis among all noncase patients stayed during the same period in ICUs. Data on 139 cases and 140 controls were deemed eligible. Among the controls, 69 patients died. The stratified Fine-Gray model was used to estimate the subdistribution Hazard ratios. The subdistribution hazards and 95% confidence intervals for final covariates were as follows: prior exposure to antimycotic agents, 2.21 (1.56-3.14); prior exposure to N-acetylcysteine, 0.11 (0.03-0.34) and prior surgical intervention, 1.26 (0.76-2.11). Of the patients, those exposed to antimycotic drugs, 87.1% (54/62) had breakthrough candidemia. Serious renal, hepatic, or hematologic side effects were comparable between patients those exposed and not-exposed to systemic antimycotic drugs. Untargeted administration of antimycotic drugs did not improve survival among candidemic patients (not-exposed, 63.6% [49/77]; exposed % 66.1 [41/62]; P = .899). This study documented that exposure to an antifungal agent is associated with increased the risk of subsequent development of CBSIs among nonneutropenic adult patients admitted to the ICU. Only two centers regularly prescribed N-acetylcysteine. Due to the limited number of subjects, we interpreted the positive effect of N-acetylcysteine on the absolute risk of CBSIs with caution.

Candidemia in Colombia

In Colombia, especially in intensive care units, candidemia is a frequent cause of infection, accounting for 88% of fungal infections in hospitalized patients, with mortality ranging from 36% to 78%. Its incidence in Colombia is higher than that reported in developed countries and even higher than in other Latin American countries. First, the patient’s risk factors should be considered, and then clinical characteristics should be assessed. Finally, microbiological studies are recommended and if the evidence supports its use, molecular testing. In general, American, Latin American, and European guides place the echinocandins as the first-line treatment for candidemia and differ in the use of fluconazole based on evidence, disease severity, previous exposure to azoles, and prevalence of Candida non-albicans. Taking into account the high incidence of this disease in our setting, it should be looked for in patients with risk factors to start a prompt empirical anti-fungal treatment.

Epidemiology and prognostic factors of nosocomial candidemia in Northeast Brazil: A six-year retrospective study

Candidemia has been considered a persistent public health problem with great impact on hospital costs and high mortality. We aimed to evaluate the epidemiology and prognostic factors of candidemia in a tertiary hospital in Northeast Brazil from January 2011 to December 2016. Demographic and clinical data of patients were retrospectively obtained from medical records and antifungal susceptibility profiling was performed using the broth microdilution method. A total of 68 episodes of candidemia were evaluated. We found an average incidence of 2.23 episodes /1000 admissions and a 30-day mortality rate of 55.9%. The most prevalent species were Candida albicans (35.3%), Candida tropicalis (27.4%), Candida parapsilosis (21.6%) and Candida glabrata (11.8%). Higher mortality rates were observed in cases of candidemia due to C. albicans (61.1%) and C. glabrata (100%), especially when compared to C. parapsilosis (27.3%). Univariate analysis revealed some variables which significantly increased the probability of death: older age (P = 0.022; odds ratio [OR] = 1.041), severe sepsis (P < 0.001; OR = 8.571), septic shock (P = 0.035; OR = 3.792), hypotension (P = 0.003; OR = 9.120), neutrophilia (P = 0.046; OR = 3.080), thrombocytopenia (P = 0.002; OR = 6.800), mechanical ventilation (P = 0.009; OR = 8.167) and greater number of surgeries (P = 0.037; OR = 1.920). Multivariate analysis showed that older age (P = 0.040; OR = 1.055), severe sepsis (P = 0.009; OR = 9.872) and hypotension (P = 0.031; OR = 21.042) were independently associated with worse prognosis. There was no resistance to amphotericin B, micafungin or itraconazole and a low rate of resistance to fluconazole (5.1%). However, 20.5% of the Candida isolates were susceptible dose-dependent (SDD) to fluconazole and 7.7% to itraconazole. In conclusion, our results could assist in the adoption of strategies to stratify patients at higher risk for developing candidemia and worse prognosis, in addition to improve antifungal management.

The impact of age on risk assessment, therapeutic practice and outcome in candidemia

BACKGROUND

In Norway, the epidemiological situation of candidemia is followed closely. We have previously demonstrated the highest incidence of candidemia in elderly >65 years of age. However, knowledge of other aspects of this infection is lacking.

OBJECTIVE

The aim of this nationwide, retrospective study was to examine risk factors, therapeutic practice and outcome in adult candidemia patients according to age.

METHODS

We retrieved data from medical records from patients who developed candidemia in Norway between 1 January 2008 and 31 December 2012. Data were analyzed according to age, younger patients being between 18 and 65 years, elderly being ≥65 years of age.

RESULTS

From 771 eligible patients, 738 patients (95.7%) were included (58% men, mean age 65.2 years, 58.1% being ≥65 years). Exposure to health-care related risk factors for candidemia were significantly more common in the younger patients (neutropenia, central venous catheter, mechanical ventilation and chemotherapy) who received empirical treatment more often than the elderly (29.8% vs. 21.7%, p = .01). More elderly did not received any antifungal therapy (27.3% vs 16.8%, p < 0001) and had higher mortality compared to younger patients (45.5% vs 23.9%, p < .0001). In the study population, mortality was higher with age (per 10-years increase, OR 1.43;1.28-1.59, p < 0.0001), in patients not receiving targeted therapy (OR 2.5; CI 1.82-3.36, p < .0001) or any therapy at all (OR 4.64; 3.23-6.68, p < .0001).

CONCLUSIONS

Risk factors for candidemia, treatment and outcome differed significantly according to age. Given the increasing numbers of elderly, scrutiny on our clinical practice is warranted.

Commensal Candida albicans Positively Calibrates Systemic Th17 Immunological Responses

Mucosal barriers are densely colonized by pathobiont microbes such as Candida albicans, capable of invasive disseminated infection. However, systemic infections occur infrequently in healthy individuals, suggesting that pathobiont commensalism may elicit host benefits. We show that intestinal colonization with C. albicans drives systemic expansion of fungal-specific Th17 CD4+ T cells and IL-17 responsiveness by circulating neutrophils, which synergistically protect against C. albicans invasive infection. Protection conferred by commensal C. albicans requires persistent fungal colonization and extends to other extracellular invasive pathogens such as Staphylococcus aureus. However, commensal C. albicans does not protect against intracellular influenza virus infection and exacerbates allergic airway inflammation susceptibility, indicating that positively calibrating systemic Th17 responses is not uniformly beneficial. Thus, systemic Th17 inflammation driven by CD4+ T cells responsive to tonic stimulation by commensal C. albicans improves host defense against extracellular pathogens, but with potentially harmful immunological consequences.

An Estimate of the Burden of Fungal Disease in Norway

The aim of this study was to examine the burden of fungal disease in Norway, contributing to a worldwide effort to improve awareness of the needs for better diagnosis and treatment of such infections. We used national registers and actual data from the Departments of Microbiology from 2015 and estimated the incidence and/or prevalence of superficial, allergic and invasive fungal disease using published reports on specific populations at risk. One in 6 Norwegians suffered from fungal disease: Superficial skin infections (14.3%: 745,600) and recurrent vulvovaginal candidiasis in fertile women (6%: 43,123) were estimated to be the most frequent infections. Allergic fungal lung disease was estimated in 17,755 patients (341/100,000). Pneumocystis jirovecii was diagnosed in 262 patients (5/100,000), invasive candidiasis in 400 patients (7.7/100,000), invasive aspergillosis in 278 patients (5.3/100,000) and mucormycosis in 7 patients (0.1/100,000). Particular fungal infections from certain geographic areas were not observed. Overall, 1.79% of the population was estimated to be affected by serious fungal infections in Norway in 2015. Even though estimates for invasive infections are small, the gravity of such infections combined with expected demographic changes in the future emphasizes the need for better epidemiological data.

Epidemiology and antifungal susceptibilities of yeast isolates causing invasive infections across urban Beijing, China

AIM

To investigate the species distribution and antifungal susceptibility profiles of yeast isolates causing invasive infections across Beijing.

MATERIALS & METHODS

A total of 1201 yeast isolates recovered from blood and other sterile body fluids were correctly identified by matrix-assisted laser desorption/ionization TOF MS supplemented by DNA sequencing. Antifungal susceptibility testing was performed according to the Clinical and Laboratory Standards Institute broth microdilution method.

RESULTS

Candida (95.5%) remained the most common yeast species isolated; Candida albicans (38.8%) and Candida parapsilosis (22.6%) were the leading species of candidemia. Azole resistances were mainly observed in Candida glabrata and Candida tropicalis isolates.

CONCLUSION

This study outlined the epidemiologic data of invasive yeast infections and highlighted the need for continuous monitoring of azole resistances among C. glabrata and C. tropicalis isolates in Beijing.

Epidemiological and mycological characteristics of candidemia in Iran: A systematic review and meta-analysis

To date, there has been no comprehensive review of the epidemiology, risk factors, species distribution, and outcomes of candidemia in Iran. This study aimed to perform a systematic review and meta-analysis of all reported candidemia cases in Iran until December 2015. The review process occurred in three steps, namely a literature search, data extraction and statistical analyses. After a comprehensive literature search, we identified 55 cases. The mean age of patients was 46.80±24.30 years (range 1-81 years). The main risk factors for candidemia were surgery and burns (23.6%), followed by malignancies (20%), use of broad-spectrum antibiotics (18.2%), and diabetes (7.3%). Candida parapsilosis (n=17, 30.8%) was the leading agent, followed by Candida albicans (n=15, 27.3%), Candida glabrata (n=10, 18.2%), and Candida tropicalis (n=8, 14.5%). The frequencies of candidemia cases due to C. glabrata, C. parapsilosis, and C. albicans were significantly higher among patients aged>60, 21-40, and 41-60 years, respectively. Comparison of risk factors for candidemia by multiple logistic regression showed that one of the most important risk factors was surgery (OR: 4.245; 95% CI: 1.141-15.789; P=0.031). The outcome was recorded in only 19 cases and 13 of those patients (68.4%) expired. This study confirms that knowledge of the local epidemiology is important when conducting surveillance studies to prevent and control candidemia and will be of interest for antifungal stewardship.

The Changing Epidemiology of Invasive Fungal Infections

Invasive fungal infections (IFI) are an emerging problem worldwide with invasive candidiasis and candidemia responsible for the majority of cases. This is predominantly driven by the widespread adoption of aggressive immunosuppressive therapy among certain patient populations (e.g., chemotherapy, transplants) and the increasing use of invasive devices such as central venous catheters (CVCs). The use of new immune modifying drugs has also opened up an entirely new spectrum of patients at risk of IFIs. While the epidemiology of candida infections has changed in the last decade, with a gradual shift from C. albicans to non-albicans candida (NAC) strains which may be less susceptible to azoles, these changes vary between hospitals and regions depending on the type of population risk factors and antifungal use. In certain parts of the world, the incidence of IFI is strongly linked to the prevalence of other disease conditions and the ecological niche for the organism; for instance cryptococcal and pneumocystis infections are particularly common in areas with a high prevalence of HIV disease. Poorly controlled diabetes is a major risk factor for invasive mould infections. Environmental factors and trauma also play a unique role in the epidemiology of mould infections, with well-described hospital outbreaks linked to the use of contaminated instruments and devices. Blastomycosis is associated with occupational exposure (e.g., forest rangers) and recreational activities (e.g., camping and fishing).The true burden of IFI is probably an underestimate because of the absence of reliable diagnostics and lack of universal application. For example, the sensitivity of most blood culture systems for detecting candida is typically 50 %. The advent of new technology including molecular techniques such as 18S ribosomal RNA PCR and genome sequencing is leading to an improved understanding of the epidemiology of the less common mould and dimorphic fungal infections. Molecular techniques are also providing a platform for improved diagnosis and management of IFI.Many factors affect mortality in IFI, not least the underlying medical condition, choice of therapy, and the ability to achieve early source control. For instance, mortality due to pneumocystis pneumonia in HIV-seronegative individuals is now higher than in seropositive patients. Of significant concern is the progressive increase in resistance to azoles and echinocandins among candida isolates, which appears to worsen the already significant mortality associated with invasive candidiasis. Mortality with mould infections approaches 50 % in most studies and varies depending on the site, underlying disease and the use of antifungal agents such as echinocandins and voriconazole. Nevertheless, mortality for most IFIs has generally fallen with advances in medical technology, improved care of CVCs, improved diagnostics, and more effective preemptive therapy and prophylaxis.

MEDical wards Invasive Candidiasis ALgorithms (MEDICAL):Consensus proposal for management

INTRODUCTION

A majority of invasive Candida infections occur in medical wards; however, evidence for management in this setting is scarce and based primarily on the intensive care or surgical setting. On behalf of the Italian Society for Anti-Infective Therapy (SITA) and the Italian Federation of Associations of Hospital Doctors on Internal Medicine (FADOI), the MEDICAL group produced practical management algorithms for patients in internal medicine wards.

METHODS

The MEDICAL group panel, composed of 30 members from internal medicine, infectious disease, clinical pharmacology, clinical microbiology and clinical epidemiology, provided expert opinion through the RAND/UCLA method.

RESULTS

Seven clinical scenarios were constructed based on clinical severity and probability of invasive candidiasis. For each scenario, the appropriateness of 63 different diagnostic, imaging, management, or therapeutic procedures was determined in two Delphi rounds. The necessity for performing each appropriate procedure, was then determined in a third Delphi round. Results were summarized in algorithms.

DISCUSSION

The proposed algorithms provide internal medicine physicians and managers with an easy to interpret tool that is exhaustive, clear and suitable for adaption to individual local settings. Attention was paid to individual patient management and resource allocation.

Admission to the Intensive Care Unit is Associated With Changes in the Oral Mycobiome

A prospective exploratory study was conducted to characterize the oral mycobiome at baseline and determine whether changes occur after admission to the intensive care unit (ICU). We found that ICU admission is associated with alterations in the oral mycobiome, including an overall increase in Candida albicans.

Potential Use of Phenolic Acids as Anti-Candida Agents: A Review

There has been a sharp rise in the occurrence of Candida infections and associated mortality over the last few years, due to the growing body of immunocompromised population. Limited number of currently available antifungal agents, undesirable side effects and toxicity, as well as emergence of resistant strains pose a considerable clinical challenge for the treatment of candidiasis. Therefore, molecules that derived from natural sources exhibiting considerable antifungal properties are a promising source for the development of novel anti-candidal therapy. Phenolic compounds isolated from natural sources possess antifungal properties of interest. Particularly, phenolic acids have shown promising in vitro and in vivo activity against Candida species. However, studies on their mechanism of action alone or in synergism with known antifungals are still scarce. This review attempts to discuss the potential use, proposed mechanisms of action and limitations of the phenolic acids in anti-candidal therapy.

Quick Detection of FKS1 Mutations Responsible for Clinical Echinocandin Resistance in Candida albicans

A rapid molecular-based assay for the detection of the Candida albicans FKS1 gene mutations responsible for resistance to echinocandin drugs was designed and evaluated. The assay consisted of a multiplexed PCR set of 5 tubes able to detect the most commonly described resistance mechanism, including FKS1 hot spot 1 and hot spot 2 mutations. The performance and specificity of the assay was evaluated using a double-blinded panel of 50 C. albicans strains. The assay showed a sensitivity of 96% and was able to detect all homozygous mutants included in the collection of strains, demonstrating that it is a robust, quick, and labor-saving method that is suitable for a routine clinical diagnostic laboratory.