Persistent Candidemia: Causes and Investigations

Candida albicans Recovered From Persistent Candidemia Exhibits Enhanced Virulence Traits

Candida albicans catheter-related candidemia is largely driven by microbial adhesion and biofilm formation on central venous catheters. Cells that disperse from these biofilms can enter the bloodstream, spread to distant organs, and sustain the cycle of infection. In this study, we investigated the virulence potential of C. albicans isolates obtained from the blood of catheterized patients experiencing persistent candidemia, comparing them to isolates that were cleared from the bloodstream early in the infection. Our results show that isolates persisting in the bloodstream for 4 days or longer, despite antifungal treatment, exhibited enhanced adherence, filamentation, and biofilm formation in vitro, along with increased expression of key virulence-related genes. Notably, cells dispersed from second-generation biofilms formed by these persistent isolates displayed even more pronounced pathogenic characteristics, including improved immune evasion. Furthermore, in vivo experiments using Galleria mellonella revealed that persistent isolates were significantly more virulent than their nonpersistent counterparts.

Persistence of Stenotrophomonas maltophilia in Patients with Bacteremia: Incidence, Clinical and Microbiologic Characters, and Outcomes

The risk factors and outcomes associated with persistent Stenotrophomonas maltophilia bacteremia are not well-defined. This retrospective cohort study analyzed 214 cases of S. maltophilia bacteremia diagnosed between 2005 and 2022 at two university hospitals, focusing on the clinical and microbiologic characteristics and outcomes of persistent bacteremia. Persistent S. maltophilia bacteremia, defined as the detection of S. maltophilia for ≥5 days after the initial blood culture, occurred in 25.7% of cases and was significantly associated with mechanical ventilation, polymicrobial infections, and increased 30-day mortality. The early administration of appropriate antibiotics reduced the likelihood of persistence. Isolates from persistent cases demonstrated increased biofilm formation. Molecular typing revealed no specific genotype linked to bacteremia persistence. Resistance to trimethoprim-sulfamethoxazole significantly increased over the study period. Our study offers new insights into the under-explored issue of persistent S. maltophilia bacteremia, a condition that constitutes a notable proportion of bloodstream infections and carries high mortality.

Clinical Characteristics of Candidemia Due to Candida parapsilosis with Serial Episodes: Insights from 5-Year Data Collection at a Tertiary Hospital in Korea

Candida parapsilosis is a common cause of non-albicans Candida species causing candidemia, particularly invasive candidiasis. This study aimed to characterize candidemia due to the C. parapsilosis complex with serial episodes, including clinical and mycological features.

METHODS

Blood isolates of the C. parapsilosis complex were collected from February 2019 to January 2023 at a tertiary Korean hospital. Species identification was performed using Vitek 2 or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antifungal susceptibility testing was performed using the Sensititre YeastOne® system. Clinical information was collected, and characteristics were analyzed according to single or serial isolates.

RESULTS

A total of 586 blood isolates of the C. parapsilosis complex were recovered from 68 candidemia patients during the study period. Of them, only the first isolate per patient was investigated. The only two isolates were resistant to fluconazole and no isolate was resistant to echinocandins, amphotericin B, or 5-FC. A single episode of candidemia occurred in 35 patients, while serial episodes occurred in 33 patients. Underlying liver diseases, use of vasopressors, ICU admission, severe sepsis, and CVC use were more frequent in patients with serial episodes. There was no significant difference in the median MIC values of antifungal agents or the use of azoles or amphotericin B between single and serial episodes. However, patients with serial episodes more frequently received echinocandin therapy. Overall, there was no significant difference in the 30-day mortality rate between patients with single and serial episodes.

CONCLUSION

Our data indicate that several factors related to the underlying conditions of the patients are associated with C. parapsilosis candidemia with serial episodes, rather than the characteristics of Candida itself.

Candidemia in Adult Patients in the ICU: A Reappraisal of Susceptibility Testing and Antifungal Therapy

OBJECTIVE

To provide updates on the epidemiology and recommendations for management of candidemia in patients with critical illness.

DATA SOURCES

A literature search using the PubMed database (inception to March 2023) was conducted using the search terms "invasive candidiasis," "candidemia," "critically ill," "azoles," "echinocandin," "antifungal agents," "rapid diagnostics," "antifungal susceptibility testing," "therapeutic drug monitoring," "antifungal dosing," "persistent candidemia," and "Candida biofilm."

STUDY SELECTION/DATA EXTRACTION

Clinical data were limited to those published in the English language. Ongoing trials were identified through ClinicalTrials.gov.

DATA SYNTHESIS

A total of 109 articles were reviewed including 25 pharmacokinetic/pharmacodynamic studies and 30 studies including patient data, 13 of which were randomized controlled clinical trials. The remaining 54 articles included fungal surveillance data, in vitro studies, review articles, and survey data. The current 2016 Infectious Diseases Society of America (IDSA) Clinical Practice Guideline for the Management of Candidiasis provides recommendations for selecting empiric and definitive antifungal therapies for candidemia, but data are limited regarding optimized dosing strategies in critically ill patients with dynamic pharmacokinetic changes or persistent candidemia complicated.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Outcomes due to candidemia remain poor despite improved diagnostic platforms, antifungal susceptibility testing, and antifungal therapy selection for candidemia in critically ill patients. Earlier detection and identification of the species causing candidemia combined with recognition of patient-specific factors leading to dosing discrepancies are crucial to improving outcomes in critically ill patients with candidemia.

CONCLUSIONS

Treatment of candidemia in critically ill patients must account for the incidence of non-albicans Candida species and trends in antifungal resistance as well as overcome the complex pathophysiologic changes to avoid suboptimal antifungal exposure.

Cyclic strain of poly (methyl methacrylate) surfaces triggered the pathogenicity of Candida albicans

Candida albicans is an opportunistic yeast and the primary etiological factor in oral candidiasis and denture stomatitis. The pathogenesis of C. albicans could be triggered by several variables, including environmental, nutritional, and biomaterial surface cues. Specifically, biomaterial interactions are driven by different surface properties, including wettability, stiffness, and roughness. Dental biomaterials experience repetitive (cyclic) stresses from chewing and biomechanical movements. Pathogenic biofilms are formed over these biomaterial surfaces under cyclic strain. This study investigated the effect of the cyclic strain (deformation) of biomaterial surfaces on the virulence of Candida albicans. Candida biofilms were grown over Poly (methyl methacrylate) (PMMA) surfaces subjected to static (no strain) and cyclic strain with different levels (ε˜x=0.1 and 0.2%). To evaluate the biomaterial-biofilm interactions, the biofilm characteristics, yeast-to-hyphae transition, and the expression of virulent genes were measured. Results showed the biofilm biomass and metabolic activity to be significantly higher when Candida adhered to surfaces subjected to cyclic strain compared to static surfaces. Examination of the yeast-to-hyphae transition showed pseudo-hyphae cells (pathogenic) in cyclically strained biomaterial surfaces, whereas static surfaces showed spherical yeast cells (commensal). RNA sequencing was used to determine and compare the transcriptome profiles of cyclically strained and static surfaces. Genes and transcription factors associated with cell adhesion (CSH1, PGA10, and RBT5), biofilm formation (EFG1), and secretion of extracellular matrix (ECM) (CRH1, ADH5, GCA1, and GCA2) were significantly upregulated in the cyclically strained biomaterial surfaces compared to static ones. Genes and transcription factors associated with virulence (UME6 and HGC1) and the secretion of extracellular enzymes (LIP, PLB, and SAP families) were also significantly upregulated in the cyclically strained biomaterial surfaces compared to static. For the first time, this study reveals a biomaterial surface factor triggering the pathogenesis of Candida albicans, which is essential for understanding, controlling, and preventing oral infections. STATEMENT OF SIGNIFICANCE: Fungal infections produced by Candida albicans are a significant contributor to various health conditions. Candida becomes pathogenic when certain environmental conditions change, including temperature, pH, nutrients, and CO2 levels. In addition, surface properties, including wettability, stiffness, and roughness, drive the interactions between Candida and biomaterials. Clinically, Candida adheres to biomaterials that are under repetitive deformation due to body movements. In this work, we revealed that when Candida adhered to biomaterial surfaces subjected to repetitive deformation, the microorganism becomes pathogenic by increasing the formation of biofilms and the expression of virulent factors related to hyphae formation and secretion of enzymes. Findings from this work could aid the development of new strategies for treating fungal infections in medical devices or implanted biomaterials.

Epidemiology, antifungal susceptibility, risk factors, and mortality of persistent candidemia in adult patients in China: a 6-year multicenter retrospective study

BACKGROUND

Data on persistent candidemia (PC), a recognized complication of candidemia, are lacking in China. This study aimed to investigate the clinical characteristics and risk factors for the mortality of PC among adults in China.

METHODS

This 6-year retrospective study analyzed the prevalence, species distribution, antifungal susceptibility, risk factors, and patient mortality of PC among adults in three regional tertiary teaching hospitals in China from 2016 to 2021. We collected electronic laboratory records data of PC and non-PC patients and used the Student test or Mann-Whitney U test for a retrospective study. Logistic regression was used to identify risk factors associated with persistent candidemia.

RESULTS

The definition of PC was fulfilled by 36 patients (13.7%, 36/263). The mean age of the patients was 59.9 years (60 years for patients with PC; 59.8 years for those with non-PC; P > 0.05) and 131 (60.1%) were men [16 with PC (44.4%), 115 with non-PC (63.2%), P < 0.05]. The mean annual incidence was 0.15/1000 admissions (including PC 0.03/1000 admissions vs. non-PC 0.12/1000 admissions, P < 0.05). Candida parapsilosis (14/36, 38.9%) and Candida albicans (81/182, 44.5%) were the predominant pathogens in patients with PC and non-PC, respectively. Most isolates were susceptible to flucytosine (99.0%) and amphotericin B (99.5%), and the activity of antifungal agents against Candida species was not statistically significantly different between patients with PC and non-PC (P > 0.05). The 30-day mortality rate was 20.2% (16.7% with PC vs. 20.9% with non-PC, P > 0.05). Multivariable regression analysis showed that use of broad-spectrum antibiotics (odds ratio (OR), 5.925; 95% confidence interval (CI), 1.886-18.616, P = 0.002), fluconazole (OR, 3.389; 95% CI, 1.302-8.820, P = 0.012) and C. parapsilosis infection (OR, 6.143; 95% CI, 2.093-18.031, P = 0.001) were independent predictors of PC, sex (male) (OR, 0.199; 95% CI, 0.077-0.518, P = 0.001) was the protective factor for PC. Respiratory dysfunction (OR, 5.763; 95% CI, 1.592-20.864, P = 0.008) and length of hospital stay(OR, 0.925; 95% CI, 0.880-0.973, P = 0.002) were independent predictors of 30-day mortality in patients with non-PC. C. tropicalis bloodstream infection (OR, 12.642; 95% CI, 1.059-150.951; P = 0.045) was an independent predictor of 30-day mortality in patients with PC.

CONCLUSIONS

The epidemiological data of patients with PC and non-PC were different in the distribution of Candida species, the mean annual incidence and independent predictors of 30-day mortality. Flucytosine and amphotericin B could be used as first-choice drugs in the presence of PC infections.

Prognostic Trends and Current Challenges in Candidemia: A Comparative Analysis of Two Multicenter Cohorts within the Past Decade

Candidemia remains a major public health challenge due to its high mortality rates, especially in developing countries. Monitoring epidemiological trends may provide insights for better clinical outcomes. This study aimed to describe trends in the epidemiology, therapeutic practices, and mortality in candidemia through a retrospective comparative analysis between two surveillance cohorts of all candidemic adults at eleven tertiary hospitals in Brazil, from 2010-2011 (Period I) versus 2017-2018 (Period II). A total of 616 cases were diagnosed, with 247 being from Period II. These patients were more likely to have three or more coexisting comorbidities [72 (29.1%) vs. 60 (16.3%), p < 0.001], had a prior history of in-hospital admissions more often [102 (40.3%) vs. 79 (21.4%), p = 0.001], and presented with candidemia earlier after admission, within 15 days (0-328) vs. 19 (0-188), p = 0.01. Echinocandins were more frequently prescribed [102 (41.3%) vs. 50 (13.6%), p = 0.001], but time to antifungal initiation [2 days (0-14) vs. 2 (0-13), p = 0.369] and CVC removal within 48 h [90/185 (48.6%) vs. 148/319 (46.4%), p = 0.644] remained unchanged. Additionally, many patients went untreated in both periods I and II [87 (23.6%) vs. 43 (17.4%), p = 0.07], respectively. Unfortunately, no improvements in mortality rates at 14 days [123 (33.6%) vs. 93 (37.7%), p = 0.343] or at 30 days [188 (51.4%) vs. 120 (48.6%), p = 0.511] were observed. In conclusion, mortality rates remain exceedingly high despite therapeutic advances, probably associated with an increase in patients' complexity and suboptimal therapeutic interventions. Management strategies should be tailored to suit epidemiological changes, expedite diagnosis to reduce the number of untreated eligible patients and guarantee early antifungal initiation and source control.

Clinical and Epidemiological Characteristics of Persistent Bacteremia: A Decadal Observational Study

Background: Bloodstream infections (BSIs), including persistent bacteremia (PB), are a leading source of morbidity and mortality globally. PB has a higher mortality rate than non- PB, but the clinical aspects of PB in terms of the causative pathogens and the presence of clearance of PB are not well elucidated. Therefore, this study aimed to describe the clinical and epidemiological characteristics of PB in a real-world clinical setting. Methods: We performed a retrospective observational survey of patients who underwent blood culture between January 2012 and December 2021 at Tohoku University Hospital. Cases of PB were divided into three groups depending on the causative pathogen: gram-positive cocci (GPC), gram-negative rods (GNRs), and Candida spp. For each group, we examined the clinical and epidemiological characteristics of PB, including differences in clinical features depending on the clearance of PB. The main outcome variable was mortality, assessed as early (30-day), late (30-90 day), and 90-day mortality. Results: Overall, we identified 31,591 cases of single bacteremia; in 6709 (21.2%) cases, the first blood culture was positive, and in 3124 (46.6%) cases, a follow-up blood culture (FUBC) was performed. Of the cases with FUBCs, 414 (13.2%) were confirmed to be PB. The proportion of PB cases caused by Candida spp. was significantly higher (29.6%, 67/226 episodes) than that for GPC (11.1%, 220/1974 episodes, p < 0.001) and GNRs (12.1%, 100/824 episodes, p < 0.001). The Candida spp. group also had the highest late (30-90 day) and 90-day mortality rates. In all three pathogen groups, the subgroup without the clearance of PB tended to have a higher mortality rate than the subgroup with clearance. Conclusions: Patients with PB due to Candida spp. have a higher late (30-90 day) and 90-day mortality rate than patients with PB due to GPC or GNRs. In patients with PB, FUBCs and confirming the clearance of PB are useful to improve the survival rate.

Recurrent Candidemia: Trends and Risk Factors Among Persons Residing in 4 US States, 2011-2018

Background

Candidemia is a common healthcare-associated infection with high mortality. Estimates of recurrence range from 1% to 17%. Few studies have focused on those with recurrent candidemia, who often experience more severe illness and greater treatment failure. We describe recurrent candidemia trends and risk factors.

Methods

We analyzed population-based candidemia surveillance data collected during 2011-2018. Persons with >1 episode (defined as the 30-day period after a positive Candida species) were classified as having recurrent candidemia. We compared factors during the initial episode between those who developed recurrent candidemia and those who did not.

Results

Of the 5428 persons identified with candidemia, 326 (6%) had recurrent infection. Recurrent episodes occurred 1.0 month to 7.6 years after any previous episode. In multivariable logistic regression controlling for surveillance site and year, recurrent candidemia was associated with being 19-44 years old (vs ≥65 years; adjusted odds ratio [aOR], 3.05 [95% confidence interval {CI}, 2.10-4.44]), being discharged to a private residence (vs medical facility; aOR, 1.53 [95% CI, 1.12-2.08]), hospitalization in the 90 days prior to initial episode (aOR, 1.66 [95% CI, 1.27-2.18]), receipt of total parenteral nutrition (aOR, 2.08 [95% CI, 1.58-2.73]), and hepatitis C infection (aOR, 1.65 [95% CI, 1.12-2.43]).

Conclusions

Candidemia recurrence >30 days after initial infection occurred in >1 in 20 persons with candidemia. Associations with younger age and hepatitis C suggest injection drug use may play a modifiable role. Prevention efforts targeting central line care and total parenteral nutrition use may help reduce the risk of recurrent candidemia.

Discovery of novel indole and indoline derivatives against Candida albicans as potent antifungal agents

With the widespread use of azole antifungals in the clinic, the drug resistance has been emerging continuously. In this work, we have designed and prepared a series of novel indole and indoline derivatives, and in vitro antifungal activity against C. albicans were evaluated. The results showed that title compounds exhibited good antifungal effect on Azole-resistant C. albicans. Further mechanism study demonstrated that S18 could inhibit the biofilm formation and hyphae growth of C. albicans through the Ras-cAMP-PKA signaling pathway.

Prognostic factors of Candida spp. bloodstream infection in adults: A nine-year retrospective cohort study across tertiary hospitals in Brazil and Spain

Background

Mortality rates among adults with candidemia vary widely in different geographical settings. Studies directly comparing epidemiology and clinical practices between countries are scarce and could bring insights into improving clinical outcomes.

Methods

Retrospective cohort including adults with candidemia diagnosed in five tertiary hospitals from Brazil and Spain between 2010-2018. Adequate therapeutic management included appropriate antifungal therapy and central-venous-catheter (CVC) removal within 48 h of fungemia. Primary endpoints were mortality rates at 14 and 30 days. Secondary endpoints were prognostic factors associated with 30-day mortality.

Findings

Overall, 720 patients were included, being 323 from Spain. Spanish patients received echinocandins more often (52·5% vs. 39·3%, p = 0.001), initiated antifungals earlier [2 (0-7) vs. 2 days (0-16), p<0.001], and had faster CVC-removal [1 (0-42) vs. 2 days (0-38), p = 0.012]. Mortality was higher among Brazilians at 14 days (35·8% vs. 20·1%, p<0.001), and at 30 days (51·9% vs. 31·6%, p < 0.001). Factors associated with mortality included: age [OR 1·02, 95%CI (1·008-1·032), p = 0·001], neutropenia [OR 3·24, 95%CI (1·594-6·585), p = 0·001], chronic pulmonary disease [OR 2·26, 95%CI (1·495-3·436), p < 0·001], corticosteroids [OR 1·45, 95%CI (1·018-2·079), p = 0·039], Pitt-Score>1 [OR 2·56, 95%CI (1·776-3·690), p < 0·001], and inadequate therapeutic management [OR 2·84, 95%CI (1·685-4·800), p < 0·001]. Being from Spain [OR 0·51, 95%CI (0·359-0·726), p < 0·001] and C. parapsilosis [OR 0·36, 95%CI (0·233-0·568), p < 0·001] were protective.

Interpretation

Higher mortality rates were observed in Brazil. Factors associated with 30-day mortality included mainly epidemiological characteristics and inadequate therapeutic management. Thus, effective and prompt antifungals combined with CVC-removal still need to be emphasized in order to improve the prognosis of adults with candidemia.

Funding

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP 2017/02203-7); CAPES Foundation (PDSE 88881.187981/2018-01).

Anti-inflammatory potential of myristic acid and palmitic acid synergism against systemic candidiasis in Danio rerio (Zebrafish)

Nosocomial Candida colonization causes Systemic candidiasis in human with invasive infections in immunocompromised patients. Of all Candida spp., C. albicans is dominant in morbidity of all systemic candidiasis but C. tropicalis is phenomenal in mortality, virulence aspects and resistance development against antifungal drugs. The present study investigated the synergistic anti-virulent activity of myristic acid (MA) and palmitic acid (PA) against insidious dimorphic Candida spp. (C. albicans and C. tropicalis). In vitro and qPCR results revealed the mechanisms of MA-PA combination effectively inhibiting various virulence aspects such as biofilm, hyphal formation, secreted aspartyl proteases, lipases, ergosterol biosynthesis and drug effluxes. Further, in Danio rerio (Zebrafish), the MA-PA treatment increased the survival of animals and also the treated groups showed decreased level of fungal burden compared to the infected controls, after 3^rd day of post infection. Histopathology of vital organs and SEM analysis of skin revealed a drastic recovery and reduced the inflammation of both Candida spp. infections in MA-PA treated animals. In addition, MA-PA treatment reduced the haemolysin and increased the susceptibility of Candida spp. in human blood model. Hence, this study suggested the therapeutic utilization of MA-PA as synergistic combination for their anti-inflammatory potency against systemic candidiasis and candidemia.

Inhibitory Effect of Morin Against Candida albicans Pathogenicity and Virulence Factor Production: An in vitro and in vivo Approaches

Candida albicans is considered an exclusive etiologic agent of candidiasis, a very common fungal infection in human. The expression of virulence factors contributes highly to the pathogenicity of C. albicans. These factors include biofilm formation, yeast-to-hyphal transition, adhesins, aspartyl proteases, and phospholipases secretion. Moreover, resistance development is a critical issue for the therapeutic failure of antifungal agents against systemic candidiasis. To circumvent resistance development, the present study investigated the virulence targeted therapeutic activity of the phyto-bioactive compound morin against C. albicans. Morin is a natural compound commonly found in medicinal plants and widely used in the pharmaceutical and cosmetic products/industries. The present study explicated the significant inhibitory potential of morin against biofilm formation and other virulence factors' production, such as yeast-hyphal formation, phospholipase, and exopolymeric substances, in C. albicans. Further, qPCR analysis confirmed the downregulation of biofilm and virlence-related genes in C. albicans upon morin treatment, which is in correspondence with the in vitro bioassays. Further, the docking analysis revealed that morin shows strong affinity with Hwp-1 protein, which regulates the expression of biofilm and hyphal formation in C. albicans and, thereby, abolishes fungal pathogenicity. Moreover, the anti-infective potential of morin against C. albicans-associated systemic candidiasis is confirmed through an in vivo approach using biomedical model organism zebrafish (Danio rerio). The outcomes of the in vivo study demonstrate that the morin treatment effectively rescues animals from C. albicans infections and extends their survival rate by inhibiting the internal colonization of C. albicans. Histopathology analysis revealed extensive candidiasis-related pathognomonic changes in the gills, intestine, and kidney of animals infected with C. albicans, while no extensive abnormalities were observed in morin-treated animals. The results evidenced that morin has the ability to protect against the pathognomonic effect and histopathological lesions caused by C. albicans infection in zebrafish. Thus, the present study suggests that the utilization of morin could act as a potent therapeutic medication for C. albicans instigated candidiasis.

Risk factors and outcomes of patients with ocular involvement of candidemia

Background

Ocular involvement of candidemia can result in serious complications, including vision loss. This study investigated the risk factors for ocular involvement in patients with candidemia and the outcomes of treatment.

Methods

Episodes of candidemia in hospitalized adults who underwent ophthalmic examinations within 2 weeks of candidemia onset between January 2014 and May 2017 were retrospectively reviewed. Their demographic characteristics, antifungal treatments, and visual outcomes were evaluated.

Results

During the study period, 438 adults were diagnosed with candidemia, with 275 (62.8%) undergoing ophthalmic examinations within 2 weeks. Of these 275 patients, 59 (21.5%) had fundoscopic abnormalities suggestive of ocular involvement, including 51 with chorioretinitis and eight with Candida endophthalmitis. Eleven patients were symptomatic. Persistent candidemia (adjusted odd ratio [aOR], 2.55; 95% confidence interval [CI], 1.29–5.08; P = 0.01), neutropenia during the preceding 2 weeks (aOR, 2.92; 95% CI, 1.14–7.53; P = 0.03), and C. albicans infection (aOR, 2.15; 95% CI, 1.09–4.24; P = 0.03) were independently associated with ocular involvement. Among the 24 patients with neutropenia, 41.7% had ocular involvements at the initial examination. Ophthalmologic examination even before the neutrophil recovery was positive in one-third of neutropenic patients. Out of the 37 patients in whom ocular outcomes after 6 weeks were available, 35 patients showed favorable or stable fundoscopic findings. Two patients had decreased visual acuity despite the stable fundoscopic finding.

Conclusion

Neutropenia within two weeks of candidemia was a risk factor for ocular involvement. More than 80 percent of patients with ocular involvements were asymptomatic, emphasizing the importance of routine ophthalmic examinations. The median 6 weeks of systemic antifungal treatment resulted in favorable outcomes in 89.2% of patients.

Persistent Candidemia in adults: underlying causes and clinical significance in the antifungal stewardship era

To investigate the causes and the clinical significance of persistent candidemia (PC) in adults diagnosed in a tertiary hospital with an active antifungal stewardship program. Retrospective cohort including all adults with candidemia from 2010 to 2018. PC was defined as any positive follow-up blood culture (BC) obtained ≥ 5 days from the first BCs yielding the same Candida species. PC was detected in 35/255 (13.7%) patients. There were no differences regarding antifungal adequacy in PC vs. non-PC (94.3% vs. 82.3%, p = 0.084) and primary source control (63.3% vs. 76.4%, p = 0.172) at the time of the follow-up BCs. The average time until source control (2 [0-37] vs. 2 days [0-44], p = 0.311) or adequate antifungal treatment (2 [0-26] vs. 2 days [- 2-10], p = 0.748) was similar. Patients with PC had more non-ocular complications (31.4% vs. 10.5%, p = 0.002). No impact on 30-day mortality was observed (31.4% vs. 22.3%, p = 0.238). The only independent factor associated with PC was to have a previously undetected site of infection [OR 4.28, 95%CI (1.77-10.34), p = 0.001]. Persistent candidemia was not associated with inadequate or delayed therapeutic management, nor higher 30-day mortality rates. Timely screening and control of unexpected infection sources are encouraged to shorten hospitalization and improve patient care.

Effectiveness of echinocandins versus fluconazole for treatment of persistent candidemia: A time-dependent analysis

OBJECTIVES

Echinocandins are fungicidal and more active than fluconazole against Candida biofilms. This is known to be an important mechanism for Candida persistence. However, there is limited evidence of effectiveness of echinocandins for treating persistent candidemia.

METHODS

We prospectively observed adult patients with persistent candidemia from March 2011 to February 2016. This was defined as the isolation of the same Candida species for ≥ 5 days from blood cultures. We used a time-dependent analysis to evaluate the impact of definitive therapy on mycological eradication and overall survival at 30 days from the index date (the date of collecting the second positive blood culture).

RESULTS

We screened 1162 episodes of candidemia. Of 196 non-duplicate patients enrolled, 64 received echinocandins and 132 received fluconazole as their first definitive therapy after the index date. The rates of mycological eradication and overall survival were 67.3% and 55.6%, respectively. The factors associated with mycological eradication included receipt of an echinocandin as the definitive therapy, adequate source control, and not receiving parenteral hyperalimentation. The factors related to overall survival were APACHE II, not receiving corticosteroids, and receiving cardiovascular or abdominal surgery.

CONCLUSIONS

Echinocandins were more effective than fluconazole in achieving mycological eradication in patients with persistent candidemia.

The Impact of Biofilm Formation on the Persistence of Candidemia

This study aimed to determine the predictors of persistent candidemia and examine the impact of biofilm formation by Candida isolates in adult patients with candidemia. Of the adult patients with candidemia in Kaohsiung Chang Gung Memorial Hospital between January 2007 and December 2012, 68 case patients with persistent candidemia (repeated candidemia after a 3-day systemic antifungal therapy) and 68 control patients with non-persistent candidemia (Candida clearance from the bloodstream after a 3-day systemic antifungal therapy) were included based on propensity score matching and matching for the Candida species isolated. Biofilm formation by the Candida species was assessed in vitro using standard biomass assays. Presence of central venous catheters (CVCs) at diagnosis (adjusted odd ratio [AOR], 3.77; 95% confidence interval [CI], 1.09–13.00, p = 0.04), infection with higher biofilm forming strains of Candida species (AOR, 8.03; 95% CI, 2.50–25.81; p < 0.01), and receipt of suboptimal fluconazole doses as initial therapy (AOR, 5.54; 95% CI, 1.53–20.10; p < 0.01) were independently associated with persistent candidemia. Biofilm formation by Candida albicans, C. tropicalis, and C. glabrata strains was significantly higher in the case patients than in the controls. There were no significant differences in the overall mortality and duration of hospitalization between the two groups. Our data suggest that, other than presence of retained CVCs and use of suboptimal doses of fluconazole, biofilm formation was highly associated with development of persistent candidemia.

Echinocandins Compared to Fluconazole for Candidemia of a Urinary Tract Source: A Propensity Score Analysis

Background

Whether echinocandins could be used to treat candidemia of a urinary tract source (CUTS) is unknown. We aimed to provide current epidemiological information of CUTS and to compare echinocandin to fluconazole treatment on CUTS outcomes.

Methods

A multicenter study of adult patients with candidemia was conducted in 9 hospitals. CUTS was defined as a candidemia with concomitant candiduria by the same organism associated with significant urological comorbidity. The primary outcome assessed was clinical failure (defined by 7-day mortality or persistent candidemia) in patients treated with either an echinocandin or fluconazole. A propensity score was calculated and then entered into a regression model.

Results

Of 2176 episodes of candidemia, 128 were CUTS (5.88%). Most CUTS cases were caused by Candida albicans (52.7%), followed by Candida glabrata (25.6%) and Candida tropicalis (16.3%). Clinical failure occurred in 7 patients (20%) treated with an echinocandin and in 15 (17.1%) treated with fluconazole (P = .730). Acute renal failure (adjusted odds ratio [AOR], 3.01; 95% confidence interval [CI], 1.01-8.91; P = .047) was the only independent factor associated with clinical failure, whereas early urinary tract drainage procedures (surgical, percutaneous, or endoscopic) were identified as protective (AOR, 0.08; 95% CI, .02-.31; P < .001). Neither univariate nor multivariate analysis showed that echinocandin therapy altered the risk of clinical failure.

Conclusions

Initial echinocandin therapy was not associated with clinical failure in patients with CUTS. Notably, acute renal failure predicted worse outcomes and performing an early urologic procedure was a protective measure.

Propensity Score Analysis of the Role of Initial Antifungal Therapy in the Outcome of Candida glabrata Bloodstream Infections

Candida glabrata isolates have reduced in vitro susceptibility to azoles, which raises concerns about the clinical effectiveness of fluconazole for treating bloodstream infection (BSI) by this Candida species. We aimed to evaluate whether the choice of initial antifungal treatment (fluconazole versus echinocandins or liposomal amphotericin B [L-AmB]-based regimens) has an impact on the outcome of C. glabrata BSI. We analyzed data from a prospective, multicenter, population-based surveillance program on candidemia conducted in 5 metropolitan areas of Spain (May 2010 to April 2011). Adult patients with an episode of C. glabrata BSI were included. The main outcomes were 14-day mortality and treatment failure (14-day mortality and/or persistent C. glabrata BSI for ≥48 h despite antifungal initiation). The impact of using fluconazole as initial antifungal treatment on the patients' prognosis was assessed by logistic regression analysis with the addition of a propensity score approach. A total of 94 patients with C. glabrata BSI were identified. Of these, 34 had received fluconazole and 35 had received an echinocandin/L-AmB-based regimen. Patients in the echinocandin/L-AmB group had poorer baseline clinical status than did those in the fluconazole group. Patients in the fluconazole group were more frequently (55.9% versus 28.6%) and much earlier (median time, 3 versus 7 days) switched to another antifungal regimen. Overall, 14-day mortality was 13% (9/69) and treatment failure 34.8% (24/69), with no significant differences between the groups. On multivariate analysis, after adjusting for baseline characteristics by propensity score, fluconazole use was not associated with an unfavorable evolution (adjusted odds ratio [OR] for 14-day mortality, 1.16, with 95% confidence interval [CI] of 0.22 to 6.17; adjusted OR for treatment failure, 0.83, with 95% CI of 0.27 to 2.61). In conclusion, initial fluconazole treatment was not associated with a poorer outcome than that obtained with echinocandins/L-AmB regimens in patients with C. glabrata BSI. (This study has been registered at ClinicalTrials.gov under registration no. NCT01236261.).

Risk factors for late recurrent candidaemia. A retrospective matched case-control study

Incidence, risk factors and clinical significance of late recurrent (LR) candidaemia (>1 month between episodes) remains unclear. The 1219 episodes of candidaemia detected from January 1985 to December 2014 were reviewed. We selected all cases with more than one episode separated by at least 30 days after clinical resolution in the interim (cases) and compared each of them with two controls (patients with single episodes of candidaemia). Clinical strains were genotyped to differentiate relapses from re-infection. Eighteen patients (1.48%) had 36 episodes of LR candidaemia (median 4 months). Independent risk factors for recurrence in the multivariate analysis were: underlying gastrointestinal disease (OR 67.16; 95% CI 5.23-861.71; p 0.001) and fungaemia due to Candida parapsilosis (OR 9.10; 95% 1.33-62.00; p 0.02). All episodes of LR candidaemia diagnosed during the first 3 months were due to an intravascular source of infection, whereas in those occurring after 3 months the main source of the disease was the abdomen, followed by endocarditis, and urinary tract. Molecular typing showed that 42.9% of LR candidaemias were relapses and 57.1% were re-infections. Neither time of recurrence nor clinical origin could predict type of recurrence. LR candidaemia is a relatively rare event that is more frequent in patients who have an initial episode of candidaemia due to C. parapsilosis or an underlying gastrointestinal disease. Episodes of LR candidaemia that occur within the first 3 months should prompt an attempt to exclude an intravascular source of infection, whereas those occurring later point to an intra-abdominal origin.

[Recommendations for the management of candidemia in adults in Latin America. Grupo Proyecto Épico]

Candidemia is one of the most frequent opportunistic mycoses worldwide. Limited epidemiological studies in Latin America indicate that incidence rates are higher in this region than in the Northern Hemisphere. Diagnosis is often made late in the infection, affecting the initiation of antifungal therapy. A more scientific approach, based on specific parameters, for diagnosis and management of candidemia in Latin America is warranted. 'Recommendations for the diagnosis and management of candidemia' are a series of manuscripts that have been developed by members of the Latin America Invasive Mycosis Network. They aim to provide a set of best-evidence recommendations for the diagnosis and management of candidemia. This publication, 'Recommendations for the management of candidemia in adults in Latin America', was written to provide guidance to healthcare professionals on the management of adults who have, or who are at risk of, candidemia. Computerized searches of existing literature were performed by PubMed. The data were extensively reviewed and analyzed by members of the group. The group also met on two occasions to pose questions, discuss conflicting views, and deliberate on a series of management recommendations. 'Recommendations for the management of candidemia in adults in Latin America' includes prophylaxis, empirical therapy, therapy for proven candidemia, patient work-up following diagnosis of candidemia, duration of candidemia treatment, and central venous catheter management in patients with candidemia. This manuscript is the second of this series that deals with diagnosis and treatment of invasive candidiasis. Other publications in this series include: 'Recommendations for the diagnosis of candidemia in Latin America', 'Recommendations for the management of candidemia in children in Latin America', and 'Recommendations for the management of candidemia in neonates in Latin America'.