National surveillance of fungemia in Denmark (2004 to 2009)

The A395T mutation in ERG11 gene confers fluconazole resistance in Candida tropicalis causing candidemia

The mechanism of fluconazole resistance in Candida tropicalis is still unclear. Recently, we isolated a fluconazole-resistant strain of C. tropicalis from the blood specimen of a patient with candidemia in China. In vitro antifungal susceptibility of the isolate was determined by using CLSI M27-A3 and E-test methods. The sequence of ERG11 gene was then analyzed, and the three-dimensional model of Erg11p encoded by ERG11 gene was also investigated. The sequencing of ERG11 gene revealed the mutation of A395T in this fluconazole-resistant isolate of C. tropicalis, resulting in the Y132F substitution in Erg11p. Sequence alignment and three-dimensional model comparison of Erg11ps showed high similarity between fluconazole-susceptible isolates of C. tropicalis and Candida albicans. The comparison of the three-dimensional models of Erg11ps demonstrated that the position of the Y132F substitution in this isolate of C. tropicalis is identical to the isolate of C. albicans with fluconazole resistance resulting from Y132F substitution in Erg11p. Hence, we ascertain that the Y132F substitution of Erg11p caused by A395T mutation in ERG11 gene confers the fluconazole resistance in C. tropicalis.

Weekly use of fluconazole as prophylaxis in haematological patients at risk for invasive candidiasis

Background

The goal was to determine whether one medical centres’ unique antifungal prophylactic regimen for patients at high risk for invasive candidiasis because of their haematological malignancies, haematopoietic stem cell transplants, or high-dose chemotherapy might lead ultimately to a higher incidence of infection, to increasing fluconazole resistance, or to a shift in the predominant strain of Candida in invasive fungal episodes.

Methods

Data were collected retrospectively, for a ten-year period from ONKO-KISS surveillance records, and from hospital, medical, and pharmacy records and then evaluated with respect to incidence of fungal infection episodes, emergence of antifungal drug resistance, and predominance of specific Candida strains in isolate cultures. Fisher’s exact test and linear regression were used to compare minimum inhibitory concentrations and to compare the incidence of different Candida isolates, respectively.

Results

The incidence of infection remained quite stable over 10 years with a median of 0.67 episodes/1000 bed days. Overall, Candida glabrata was the predominant species with 29% followed by C. albicans and C. krusei (14% each). No significant increment of non-albicans Candida species with decreased fluconazole susceptibility was perceived over this decade.

Conclusions

Once weekly administration of 400 mg of fluconazole to prevent candidaemia appears to have no negative impact on the efficacy as a prophylaxis when compared to standard of care (400 mg of fluconazole daily).

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-014-0573-5) contains supplementary material, which is available to authorized users.

No specific time window distinguishes between community-, healthcare-, and hospital-acquired bacteremia, but they are prognostically robust

OBJECTIVE

We examined whether specific time windows after hospital admission reflected a sharp transition between community and hospital acquisition of bacteremia. We further examined whether different time windows to distinguish between community acquisition, healthcare association (HCA), and hospital acquisition influenced the results of prognostic models.

DESIGN

Population-based cohort study.

SETTING

Hospitals in 3 areas of Denmark (2.3 million inhabitants) during 2000-2011.

METHODS

We computed graphs depicting proportions of males, absence of comorbidity, microorganisms, and 30-day mortality pertaining to bacteremia 0, 1, 2, …, 30, and 31 days and later after admission. Next, we assessed whether different admission (0-1, 0-2, 0-3, 0-7 days) and HCA (30, 90 days) time windows were associated with changes in odds ratio (OR) and area under the receiver operating characteristic (ROC) curve for 30-day mortality, adjusting for sex, age, comorbidity, and microorganisms.

RESULTS

For 56,606 bacteremic episodes, no sharp transitions were detected on a specific day after admission. Among the 8 combined time windows, ORs for 30-day mortality varied from 1.30 (95% confidence interval [CI], 1.23-1.37) to 1.99 (95% CI, 1.48-2.67) for HCA and from 1.36 (95% CI, 1.24-1.50) to 2.53 (95% CI, 2.01-3.20) for hospital acquisition compared with community acquisition. Area under the ROC curve changed marginally from 0.684 (95% CI, 0.679-0.689) to 0.700 (95% CI, 0.695-0.705).

CONCLUSIONS

No time transitions unanimously distinguished between community and hospital acquisition with regard to sex, comorbidity, or microorganisms, and no difference in 30-day mortality was seen for HCA patients in relation to a 30- or 90-day time window. ORs decreased consistently in the order of hospital acquisition, HCA, and community acquisition, regardless of time window combination, and differences in area under the ROC curve were immaterial.

Burden of serious fungal infections in Spain

Estimates of the incidence and prevalence of serious fungal infections, based on epidemiological data, are essential in order to inform public health priorities given the lack of resources dedicated to the diagnosis and treatment of these serious fungal diseases. However, epidemiology of these infections is largely unknown, except for candidaemia and cryptococcosis. The aim of this work is to calculate the burden of serious fungal infections in Spain. All published epidemiology papers reporting fungal infection rates from Spain were identified. Where no data existed, we used specific populations at risk and fungal infection frequencies in those populations to estimate national incidence or prevalence, depending on the condition. Around 8.1 million people suffer a fungal infection every year. Most of them are skin or mucosal infections causing no deaths. Candidaemia is more common than in other European countries and has risen by 1.88-fold in frequency in the last decade (8.1 cases × 100,000). Good estimates of invasive aspergillosis (2.75 cases × 100,000) and mucormycosis (0.04 × 100,000) are available. Fungal infections with a high mortality such as invasive aspergillosis, candidaemia, Pneumocystis pneumonia and mucormycosis are not numerous in Spain, but they affect those with severe underlying diseases and are therefore linked to poor outcomes. Additional studies are required, especially for high burden diseases such as recurrent thrush in women (∼9000 cases × 100,000 women), allergic bronchopulmonary aspergillosis (126 cases × 100,000) and severe asthma with fungal sensitisation (198 cases × 100,000).

Invasive Candida infections in surgical patients in intensive care units: a prospective, multicentre survey initiated by the European Confederation of Medical Mycology (ECMM) (2006-2008)

A prospective, observational, multicentre study of invasive candidosis (IC) in surgical patients in intensive care units (ICUs) was conducted from 2006 to 2008 in 72 ICUs in 14 European countries. A total of 779 patients (62.5% males, median age 63 years) with IC were included. The median rate of candidaemia was 9 per 1000 admissions. In 10.8% the infection was already present at the time of admission to ICU. Candida albicans accounted for 54% of the isolates, followed by Candida parapsilosis 18.5%, Candida glabrata 13.8%, Candida tropicalis 6%, Candida krusei 2.5%, and other species 5.3%. Infections due to C. krusei (57.9%) and C. glabrata (43.6%) had the highest crude mortality rate. The most common preceding surgery was abdominal (51.5%), followed by thoracic (20%) and neurosurgery (8.2%). Candida glabrata was more often isolated after abdominal surgery in patients ≥60 years, and C. parapsilosis was more often isolated in neurosurgery and multiple trauma patients as well as children ≤1 year of age. The most common first-line treatment was fluconazole (60%), followed by caspofungin (18.7%), liposomal amphotericin B (13%), voriconazole (4.8%) and other drugs (3.5%). Mortality in surgical patients with IC in ICU was 38.8%. Multivariate analysis showed that factors independently associated with mortality were: patient age ≥60 years (hazard ratio (HR) 1.9, p 0.001), central venous catheter (HR 1.8, p 0.05), corticosteroids (HR 1.5, p 0.03), not receiving systemic antifungal treatment for IC (HR 2.8, p <0.0001), and not removing intravascular lines (HR 1.6, p 0.02).

Epidemiology of echinocandin resistance in Candida

Echinocandins are the newest antifungal agents approved for use in treating Candida infections in the US. They act by interfering with 1,3-β-D-glucan synthase and therefore disrupt cell wall production and lead to Candida cell death. There is no intrinsic resistance to echinocandins among Candida species, and isolates from historic collections archived before the release of the echinocandins show no resistance. Resistance to the echinocandins remains low among most Candida species and ranges overall from 0-1%. Among isolates of Candida glabrata, the proportion of resistant isolates is higher and has been reported to be as high as 13.5% in at least one hospital. Antifungal resistance is due to specific amino acid mutations in the Fksp subunit(s) of the 1,3-β-D-glucan synthase protein which are localized to one of two hotspots. These mutations are being recognized in isolates from patients who have failed echinocandin therapy, and often lead to a poor outcome. While the future looks bright for the echinocandins against most Candida species, C. glabrata remains a species of concern and resistance rates of C. glabrata to the echinocandins should be monitored closely.

Epidemiology and identification of potential fungal pathogens causing invasive fungal infections in a tertiary care hospital in northeast Thailand

Invasive fungal infections (IFIs) are life threatening and associated with a high mortality rate. Here, we describe the distribution of pathogens, host risk factors, and significance of fungi isolated from patients with IFIs. The study included 861 fungal isolates recovered between 2006 and 2011 from 802 patients at Srinagarind Hospital, Thailand. Based on the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group 2008 criteria, 28.5% (245/861 isolates) of the fungal isolates were considered to be causative agents of IFIs. The most common fungus was Candida albicans (46%, 396/861 isolates). However, the most common yeast causing IFIs was Cryptococcus neoformans (34.7%, 85/245 isolates), while the most common mould was Penicillium marneffei (10.6%, 26/245 isolates). Cryptococcosis was significantly associated with human immunodeficiency virus infections (P < 0.001). Trend analysis revealed that there was no significant increase in IFI cases (P = 0.34) from 2006 to 2011 or from 2007 to 2011 (P = 0.05), but there was a trend toward significant increases in candidiasis (P = 0.04). The fungal isolates were categorized according to the positive predictive value of their recovery in cultures as being true (>95%), moderate (5%-95%), and rare (<5%) pathogens. This classification system could facilitate the prediction of the likelihood of diseases caused by the isolated fungi.

Species distribution and susceptibility profile to fluconazole, voriconazole and MXP-4509 of 551 clinical yeast isolates from a Romanian multi-centre study

This is the first multi-centre study regarding yeast infections in Romania. The aim was to determine the aetiological spectrum and susceptibility pattern to fluconazole, voriconazole and the novel compound MXP-4509. The 551 isolates were identified using routine laboratory methods, matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and DNA sequence analysis. Susceptibility testing was performed using the European Committee for Antimicrobial Susceptibility Testing (EUCAST) method and breakpoints. The yeasts originated from superficial infections (SUP, 51.5 %), bloodstream infections (BSI, 31.6 %) and deep-seated infections (DEEP, 16.9 %), from patients of all ages. Nine genera and 30 species were identified. The 20 Candida species accounted for 94.6 % of all isolates. C. albicans was the overall leading pathogen (50.5 %). Lodderomyces elongisporus is reported for the first time as a fungaemia cause in Europe. C. glabrata and Saccharomyces cerevisiae, as well as the non-Candida spp. and non-albicans Candida spp. groups, showed decreased fluconazole susceptibility (<75 %). The overall fluconazole resistance was 10.2 %. C. krusei accounted for 27 of the 56 fluconazole-resistant isolates. The overall voriconazole resistance was 2.5 % and was due mainly to C. glabrata and C. tropicalis isolates. Fluconazole resistance rates for the three categories of infection were similar to the overall value; voriconazole resistance rates differed: 4 % for BSI, 3.2 % for DEEP and 1.4 % for SUP. The antifungal activity of MXP-4509 was superior to voriconazole against C. glabrata and many fluconazole-resistant isolates. There was a large percentage of non-albicans Candida isolates. A large part of the high fluconazole resistance was not acquired but intrinsic, resulting from the high percentage of C. krusei.

Prospective observational multicenter study to define a diagnostic algorithm for biliary candidiasis

AIM: To develop an algorithm to improve the diagnosis and treatment of patients with biliary candidiasis.

METHODS: We performed a prospective study of 127 patients who underwent endoscopic retrograde cholangiopancreatography, for various biliary disorders, at 3 tertiary referral centers in Germany from July 2011 through July 2012 (ClinicalTrials.gov: NCT01109550). Bile, buccal, and stool samples were collected. When indicated, endoscopic transpapillary bile duct biopsies were performed to clarify the etiology of bile duct strictures and to prove invasive fungal infections.

RESULTS: Candida species were detected in 38 of the 127 bile samples (29.9%). By multivariate analysis patients’ age and previous endoscopic sphincterotomy were independent risk factors for biliary candidiasis (P < 0.05). Patients with immunosuppression (P = 0.058) and recent long-term antibiotic therapy (> 7 d) (P = 0.089) tend to be at risk for biliary candidiasis. One patient was negative in mycological culture of bile fluid but invasive biliary candidiasis was diagnosed histologically. Of Candida subspecies detected, 36.7% were azole-resistant, such as C glabrata. Eight patients received anti-mycotic therapy, based on our algorithm. Of these, 3 had cancer with biliary tract involvement, 2 had secondary sclerosing cholangitis, 1 had retroperitoneal fibrosis, and 5 had septicemia. In all patients contamination was ruled out by smears of the endoscope channel.

CONCLUSION: Gastroenterologists should be aware of frequent candida colonization in patients with cholangitis and biliary disorders. Our suggested algorithm facilitates the further clinical management.

Candida bloodstream infection: a clinical microbiology laboratory perspective

The incidence of Candida bloodstream infection (BSI) has been on the rise in several countries worldwide. Species distribution is changing; an increase in the percentage of non-albicans species, mainly fluconazole non-susceptible C. glabrata was reported. Existing microbiology diagnostic methods lack sensitivity, and new methods need to be developed or further evaluation for routine application is necessary. Although reliable, standardized methods for antifungal susceptibility testing are available, the determination of clinical breakpoints remains challenging. Correct species identification is important and provides information on the intrinsic susceptibility profile of the isolate. Currently, acquired resistance in clinical Candida isolates is rare, but reports indicate that it could be an issue in the future. The role of the clinical microbiology laboratory is to isolate and correctly identify the infective agent and provide relevant and reliable susceptibility data as soon as possible to guide antifungal therapy.

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

The aim of the study was to review the epidemiology and prognosis of candidemia in a secondary hospital, and to examine the intra-hospital distribution of candidemia patients. Study design is a retrospective cohort study. Trough 2002–2012, 110 cases of candidemia were diagnosed, giving an incidence of 2, 6/100000 citizens/year. Overall prognosis of candidemia was dismal, with a 30 days case fatality rate of 49% and one year case fatality rate of 64%. Candidemia was a terminal event in 55% of 30 days non-survivors, defined as Candida blood cultures reported positive on the day of death or thereafter (39%), or treatment refrained due to hopeless short-term prognosis (16%). In terminal event candidemias, advanced or incurable cancer was present in 29%. Non-survivors at 30 days were 9 years (median) older than survivors. In 30 days survivors, candidemia was not recognised before discharge in 13% of cases. No treatment were given and no deaths or complications were observed in this group. Candidemia patients were grouped into 8 patient categories: Abdominal surgery (35%), urology (13%), other surgery (11%), pneumonia (13%), haematological malignancy (7%), intravenous drug abuse (4%), other medical (15%), and new-borns (3%). Candidemia was diagnosed while admitted in the ICU in 46% of patients. Urology related cases were all diagnosed in the general ward. Multiple surgical procedures were done in 60% of abdominal surgery patients. Antibiotics were administered prior to candidemia in 87% of patients, with median duration 17 (1–108) days. Neutropenia was less common than expected in patients with candidemia (8/105) and closely associated to haematological malignancy (6/8). Compared with previous national figures the epidemiology of invasive candidiasis seems not to have changed over the last decade.

Candidaemia observed at a university hospital in Milan (northern Italy) and review of published studies from 2010 to 2014

BACKGROUND

Candida species represent the fourth leading cause of nosocomial bloodstream infections (BSI) worldwide. However, candidaemia rates and species involved vary geographically.

OBJECTIVES

To evaluate the epidemiological pattern, risk factors for mortality and antifungal therapy of Candida BSI over a 5-year period (2008-2012) in a university hospital in northern Italy together with a review of the recent literature concerning candidaemia.

METHODS

A retrospective cohort study cross-linked with microbiology database was performed.

RESULTS

A total of 89 Candida BSI were identified in 42 males (47 %) and 47 females (52.8 %). The median age was 69 years (interquartile range 55-78) with 61.8 % of patients being older than 65 years. Considering all hospitalized patients, the overall incidence rate of candidaemia increased significantly from 2008 to 2012 (from 0.4 to 1.68 episodes per 10,000 patient/days) (p = 0.0001) with a mean linear increase in 5 new cases per year. Candida albicans was the predominant species isolated (64 %) followed by C. glabrata (19.1 %). The latter species was observed with significantly higher frequency in Internal Medicine and Intensive Care Units (ICU). In-hospital crude mortality was 41.6 %.

CONCLUSIONS

Candidaemia is an increasing BSI in our university hospital, in accordance with that observed in northern Italy, and it is still associated with high in-hospital crude mortality.

Epidemiology and outcomes of invasive candidiasis due to non-albicans species of Candida in 2,496 patients: data from the Prospective Antifungal Therapy (PATH) registry 2004-2008

This analysis describes the epidemiology and outcomes of invasive candidiasis caused by non-albicans species of Candida in patients enrolled in the Prospective Antifungal Therapy Alliance (PATH Alliance) registry from 2004 to 2008. A total of 2,496 patients with non-albicans species of Candida isolates were identified. The identified species were C. glabrata (46.4%), C. parapsilosis (24.7%), C. tropicalis (13.9%), C. krusei (5.5%), C. lusitaniae (1.6%), C. dubliniensis (1.5%) and C. guilliermondii (0.4%); 111 infections involved two or more species of Candida (4.4%). Non-albicans species accounted for more than 50% of all cases of invasive candidiasis in 15 of the 24 sites (62.5%) that contributed more than one case to the survey. Among solid organ transplant recipients, patients with non-transplant surgery, and patients with solid tumors, the most prevalent non-albicans species was C. glabrata at 63.7%, 48.0%, and 53.8%, respectively. In 1,883 patients receiving antifungal therapy on day 3, fluconazole (30.5%) and echinocandins (47.5%) were the most frequently administered monotherapies. Among the 15 reported species, 90-day survival was highest for patients infected with either C. parapsilosis (70.7%) or C. lusitaniae (74.5%) and lowest for patients infected with an unknown species (46.7%) or two or more species (53.2%). In conclusion, this study expands the current knowledge of the epidemiology and outcomes of invasive candidiasis caused by non-albicans species of Candida in North America. The variability in species distribution in these centers underscores the importance of local epidemiology in guiding the selection of antifungal therapy.

Antifungal resistance to fluconazole and echinocandins is not emerging in yeast isolates causing fungemia in a Spanish tertiary care center

Accurate knowledge of fungemia epidemiology requires identification of strains to the molecular level. Various studies have shown that the rate of resistance to fluconazole ranges from 2.5% to 9% in Candida spp. isolated from blood samples. However, trends in antifungal resistance have received little attention and have been studied only using CLSI M27-A3 methodology. We assessed the fungemia epidemiology in a large tertiary care institution in Madrid, Spain, by identifying isolates to the molecular level and performing antifungal susceptibility testing according to the updated breakpoints of European Committee for Antimicrobial Susceptibility Testing (EUCAST) definitive document (EDef) 7.2. We studied 613 isolates causing 598 episodes of fungemia in 544 patients admitted to our hospital (January 2007 to December 2013). Strains were identified after amplification and sequencing of the ITS1-5.8S-ITS2 region and further tested for in vitro susceptibility to amphotericin B, fluconazole, posaconazole, voriconazole, micafungin, and anidulafungin. Resistance was defined using EUCAST species-specific breakpoints, and epidemiological cutoff values (ECOFFs) were applied as tentative breakpoints. Most episodes were caused by Candida albicans (46%), Candida parapsilosis (28.7%), Candida glabrata (9.8%), and Candida tropicalis (8%). Molecular identification enabled us to better detect cryptic species of Candida guilliermondii and C. parapsilosis complexes and episodes of polyfungal fungemia. The overall percentage of fluconazole-resistant isolates was 5%, although it was higher in C. glabrata (8.6%) and non-Candida yeast isolates (47.4%). The rate of resistance to echinocandins was 4.4% and was mainly due to the presence of intrinsically resistant non-Candida species. Resistance mainly affected non-Candida yeasts. The rate of resistance to fluconazole and echinocandins did not change considerably during the study period.

Epidemiology, species distribution and outcome of nosocomial Candida spp. bloodstream infection in Shanghai

Background

Yeasts, mostly Candida, are important causes of bloodstream infections (BSI), responsible for significant mortality and morbidity among hospitalized patients. The epidemiology and species distribution vary from different regions. The goals of this study were to report the current epidemiology of Candida BSI in a Shanghai Teaching Hospital and estimate the impact of appropriate antifungal therapy on the outcome.

Methods

From January 2008 to December 2012, all consecutive patients who developed Candida BSI at Ruijin University Hospital were enrolled. Underlying diseases, clinical severity, species distribution, antifungal therapy and its impact on the outcome were analyzed.

Results

A total of 121 episodes of Candida BSI were identified, with an incidence of 0.32 episodes/1,000 admissions (0.21 in 2008 and 0.42 in 2012) The proportion of candidemia caused by non-albicans species (62.8%), including C. parapsilosis (19.8%), C. tropicalis (14.9%), C. glabrata (7.4%), C. guilliermondii (5.8%), C. sake (5.0%) was higher than that of candidemia caused by C. albicans (37.2%). The overall crude 28-day mortality was 28.1% and significantly reduced with appropriate empiric antifungal therapy administered within 5 days (P = 0.006). Advanced age (OR 1.04; P = 0.014), neutropenia < 500/mm³ (OR 17.44; P < 0.001) were independent risk factors for 28-day mortality, while appropriate empiric antifungal therapy (OR 0.369; P = 0.035) was protective against 28-day mortality.

Conclusion

The epidemiology of candidemia in Shanghai differed from that observed in Western countries. Appropriate empiric antifungal therapy influenced the short-term survival.

Historical trends in the epidemiology of candidaemia: analysis of an 11-year period in a tertiary care hospital in Brazil

Candida species are an important cause of bloodstream infections (BSI). To evaluate the epidemiological, clinical and microbiological aspects of two cohorts {1994-1999 [period 1 (P1) ]; 2000-2004 [period 2 (P2) ]} of candidaemic patients, we performed a retrospective analysis from a laboratory-based survey. A total of 388 candidaemias were identified, with an incidence of 0.20/1,000 patient-days and a significant increase in P2 vs. P1 (0.25 vs. 0.15, p = 0.04). Cancer and prior antibiotic use were frequent and Candida albicans was the most prevalent species found (42.4%). Resistance to fluconazole was found in 2.47% of the strains. No differences were observed in the species distribution of Candida during the study periods. In the P2 cohort, there were higher prevalence of elderly individuals, cardiac, pulmonary and liver diseases, renal failure, central venous catheters and antibiotic therapy. In P1, there were higher prevalence of neurological diseases and chemotherapy. The crude mortality was 55.4%. In conclusion, our incidence rates remained high. Furthermore, the distribution pattern of Candida species and the fluconazole resistance profile remained unchanged. Moreover, we found a clear trend of higher prevalence of candidaemia among the elderly and among patients with comorbidities. Finally, it is necessary to discuss strategies for the prevention and control of Candida BSI in Brazil.

Global trends in the distribution of Candida species causing candidemia

Only five species account for 92% of cases of candidemia (Candida albicans, C. glabrata, C. tropicalis, C. parapsilosis, and C. krusei); however, their distribution varies in population-based studies conducted in different geographical areas. C. albicans is the most frequent species, but considerable differences are found between the number of cases caused by C. glabrata and C. parapsilosis. Studies from Northern Europe and the USA reported a high number of cases caused by C. glabrata, whereas studies from Spain and Brazil demonstrated a lower number of cases caused by C. glabrata and a higher number of cases attributed to C. parapsilosis. Globally, the frequency of C. albicans is decreasing, while that of C. glabrata and C. krusei is stable, and C. parapsilosis and C. tropicalis are increasing. Patient characteristics and prior antifungal therapy also have a considerable influence on the distribution and frequency of Candida spp., regardless of the geographical area. C. albicans is more frequent in patients aged up to 18 years, the frequency of C. parapsilosis decreases with age, and C. glabrata is more common in the elderly. Finally, the presence of horizontal transmission of Candida spp. isolates (reported mainly in patients from the adult medical and post-surgical ICU, patients from oncology-haematology units, and neonates) can affect species distribution.

Association of clinical and demographic factors in invasive candidiasis caused by fluconazole-resistant Candida species: a study in 15 hospitals, Medellín, Colombia 2010-2011

Candida is the most important agent of fungal infections. Several risk factors have been described associated with invasive infection by fluconazole-resistant Candida spp. A prospective cross-sectional study with case-control analysis was conducted. Case group patients with fluconazole-resistant Candida isolate were included; control group were patients with fluconazole-susceptible Candida spp. A multivariate logistic regression model was performed. Three hundred isolates of Candida spp. were analyzed. Most frequent species were Candida albicans/Candida dubliniensis (48.3%) and Candida tropicalis (22.3%). Posaconazole susceptibility was 93.7%; voriconazole, 84%; and fluconazole, 78.7%. Susceptibility to anidulafungin and caspofungin was 92.7% and 92.3%, respectively. Neutropenia (adjusted odds ratio [aOR] 6.5, 95% confidence interval [CI] 1.0-43.1), antifungal exposure (aOR 5.1, 95% CI 2.3-11.2), and antituberculosis therapy (aOR 7.7, 95% CI 1.4-43.2) were associated to fluconazole resistance. Susceptibility results are useful to guide the selection of empiric antifungal treatment and the design of local therapeutic guidelines. Previous antifungal exposure suggests possible resistance to fluconazole, pointing towards the selection of a different class of antifungal agents.

Procalcitonin as a marker of Candida species detection by blood culture and polymerase chain reaction in septic patients

Background

The aim of our study is to test procalcitonin (PCT) as surrogate marker of identification of Candida spp. by blood culture (BC) and real-time-polymerase chain reaction (PCR), whether alone or in association with bacteria, in septic patients.

Methods

We performed a single-centre retrospective study. We reviewed the clinical charts of patients with a diagnosis of severe sepsis or septic shock treated at our general intensive care unit from March 2009 to March 2013. We analysed all diagnostic episodes consisting of BC, real-time PCR assay and dosage of PCT. We registered age, sex, white blood count, sequential organ failure assessment score and type of admission between medical or surgical. When inclusion criteria were met more than once, we registered the new diagnostic episode as subsequent diagnostic episode. The diagnostic performance of PCT to predict Candida spp. identification alone or in mixed infections by either BC or PCR was tested using the receiver-operative characteristic curve. Logistic regression was constructed using presence of Candida spp. as the dependent variable.

Results

A total of 260 diagnostic episodes met the inclusion criteria. According to BC results classification, a significantly lower value of PCT was observed in Candida spp. BSI (0.99 ng/ml, 0.86 - 1.34) than in BSI caused by bacteria (16.7 ng/ml, 7.65 - 50.2) or in mixed infections (4.76 ng/ml, 2.98 - 6.08). Similar findings were observed considering PCR results. A cut-off of ≤ 6.08 ng/ml for PCT yielded a sensitivity of 86.8%, a specificity of 87.4%, a positive predictive value of 63.9%, a negative predictive value (NPV) of 96.3% and an area under the curve of 0.93 for Candida spp. identification by BC. A similar high NPV for a cut-off ≤ 6.78 ng/ml was observed considering the classification of diagnostic episodes according to PCR results, with an AUC of 0.85. A subsequent diagnostic episode was independently associated with Candida spp. detection either by BC or PCR.

Conclusion

PCT could represent a useful diagnostic tool to exclude the detection of Candida spp. by BC and PCR in septic patients.

Epidemiology and risk factors for invasive candidiasis

The number of immunosuppressive patients has increased significantly in recent years. These patients are at risk for opportunistic infections, especially fungal infections. Candidiasis is one of the most frequent fungal infections determined in these immunosuppressive patients and its epidemiology has changed over the last two decades. Recently, new antifungal agents and new therapy strategies such as antifungal prophylaxis, secondary prophylaxis, and preemptive therapy have come into use. These changes resulted in the alteration of Candida species causing invasive infections. The incidence of Candida albicans was decreased in many countries, especially among patients with immunosuppressive disorders, while the incidence of species other than C. albicans was increased. In this review, incidence, risk factors, and species distribution of invasive candidiasis are discussed.

Update on antifungal resistance in Aspergillus and Candida

Antifungal resistance in Candida and Aspergillus may be either intrinsic or acquired and may be encountered in the antifungal drug exposed but also the antifungal drug-naïve patient. Prior antifungal treatment confers a selection pressure and notoriously raises the awareness of possible resistance in patients failing therapy, thus calling for susceptibility testing. On the contrary, antifungal resistance in the drug-naïve patient is less expected and therefore more challenging. This is particularly true when it concerns pathogens with acquired resistance which cannot be predicted from the species identification itself. This scenario is particularly relevant for A. fumigatus infections due to the increasing prevalence of azole-resistant isolates in the environment. For Candida, infections resistance is most common in the context of increasing prevalence of species with intrinsic resistance. Candida glabrata which has intrinsically reduced susceptibility to fluconazole is increasingly common particularly among the adult and elderly population on the Northern Hemisphere where it may be responsible for as many as 30% of the blood stream infections in population-based surveillance programmes. Candida parapsilosis is prevalent in the paediatric setting, at centres with increasing echinocandin use and at the southern or pacific parts of the world. In the following, the prevalence and drivers of intrinsic and acquired resistance in Aspergillus and Candida will be reviewed.

Calcineurin controls hyphal growth, virulence, and drug tolerance of Candida tropicalis

Candida tropicalis, a species closely related to Candida albicans, is an emerging fungal pathogen associated with high mortality rates of 40 to 70%. Like C. albicans and Candida dubliniensis, C. tropicalis is able to form germ tubes, pseudohyphae, and hyphae, but the genes involved in hyphal growth machinery and virulence remain unclear in C. tropicalis. Recently, echinocandin- and azole-resistant C. tropicalis isolates have frequently been isolated from various patients around the world, making treatment difficult. However, studies of the C. tropicalis genes involved in drug tolerance are limited. Here, we investigated the roles of calcineurin and its potential target, Crz1, for core stress responses and pathogenesis in C. tropicalis. We demonstrate that calcineurin and Crz1 are required for hyphal growth, micafungin tolerance, and virulence in a murine systemic infection model, while calcineurin but not Crz1 is essential for tolerance of azoles, caspofungin, anidulafungin, and cell wall-perturbing agents, suggesting that calcineurin has both Crz1-dependent and -independent functions in C. tropicalis. In addition, we found that calcineurin and Crz1 have opposite roles in controlling calcium tolerance. Calcineurin serves as a negative regulator, while Crz1 plays a positive role for calcium tolerance in C. tropicalis.

Molecular identification and antifungal susceptibility of yeast isolates causing fungemia collected in a population-based study in Spain in 2010 and 2011

We report the molecular identifications and antifungal susceptibilities of the isolates causing fungemia collected in the CANDIPOP population-based study conducted in 29 Spanish hospitals. A total of 781 isolates (from 767 patients, 14 of them having mixed fungemia) were collected. The species found most frequently were Candida albicans (44.6%), Candida parapsilosis (24.5%), Candida glabrata (13.2%), Candida tropicalis (7.6%), Candida krusei (1.9%), Candida guilliermondii (1.7%), and Candida lusitaniae (1.3%). Other Candida and non-Candida species accounted for approximately 5% of the isolates. The presence of cryptic species was low. Compared to findings of previous studies conducted in Spain, the frequency of C. glabrata has increased. Antifungal susceptibility testing was performed by using EUCAST and CLSI M27-A3 reference procedures; the two methods were comparable. The rate of fluconazole-susceptible isolates was 80%, which appears to be a decrease compared to findings of previous studies, explained mainly by the higher frequency of C. glabrata. Using the species-specific breakpoints and epidemiological cutoff values, the rate of voriconazole and posaconazole in vitro resistance was low (<2%). In the case of C. tropicalis, using the EUCAST procedure, the rate of azole resistance was around 20%. There was a correlation between the previous use of azoles and the presence of fluconazole-resistant isolates. Resistance to echinocandins was very rare (2%), and resistance to amphotericin B also was very uncommon. The sequencing of the hot spot (HS) regions from FKS1 or FKS2 genes in echinocandin-resistant isolates revealed previously described point mutations. The decrease in the susceptibility to fluconazole in Spanish isolates should be closely monitored in future studies.

Candida species distribution and antifungal susceptibility testing according to European Committee on Antimicrobial Susceptibility Testing and new vs. old Clinical and Laboratory Standards Institute clinical breakpoints: a 6-year prospective candidaemia survey from the fungal infection network of Switzerland

We analyzed the species distribution of Candida blood isolates (CBIs), prospectively collected between 2004 and 2009 within FUNGINOS, and compared their antifungal susceptibility according to clinical breakpoints defined by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) in 2013, and the Clinical and Laboratory Standards Institute (CLSI) in 2008 (old CLSI breakpoints) and 2012 (new CLSI breakpoints). CBIs were tested for susceptiblity to fluconazole, voriconazole and caspofungin by microtitre broth dilution (Sensititre® YeastOne™ test panel). Of 1090 CBIs, 675 (61.9%) were C. albicans, 191 (17.5%) C. glabrata, 64 (5.9%) C. tropicalis, 59 (5.4%) C. parapsilosis, 33 (3%) C. dubliniensis, 22 (2%) C. krusei and 46 (4.2%) rare Candida species. Independently of the breakpoints applied, C. albicans was almost uniformly (>98%) susceptible to all three antifungal agents. In contrast, the proportions of fluconazole- and voriconazole-susceptible C. tropicalis and F-susceptible C. parapsilosis were lower according to EUCAST/new CLSI breakpoints than to the old CLSI breakpoints. For caspofungin, non-susceptibility occurred mainly in C. krusei (63.3%) and C. glabrata (9.4%). Nine isolates (five C. tropicalis, three C. albicans and one C. parapsilosis) were cross-resistant to azoles according to EUCAST breakpoints, compared with three isolates (two C. albicans and one C. tropicalis) according to new and two (2 C. albicans) according to old CLSI breakpoints. Four species (C. albicans, C. glabrata, C. tropicalis and C. parapsilosis) represented >90% of all CBIs. In vitro resistance to fluconazole, voriconazole and caspofungin was rare among C. albicans, but an increase of non-susceptibile isolates was observed among C. tropicalis/C. parapsilosis for the azoles and C. glabrata/C. krusei for caspofungin according to EUCAST and new CLSI breakpoints compared with old CLSI breakpoints.

Epidemiology of candidaemia and invasive candidiasis. A changing face

Invasive candidiasis is a leading cause of mortality. Candidaemia is the most common clinical presentation of invasive candidiasis but more that 30% of these infections do not yield positive blood cultures. Candida albicans remains the predominant aetiology, accounting for 50% of all cases. However, there has been an epidemiological shift in the last decades. Some species of Candida different to C. albicans have emerged as an important cause of severe candidaemia as they can exhibit resistance to fluconazole and other antifungal agents. Moreover, there is a different distribution of non C. albicans Candida species in relationship to patients' and hospital characteristics. Thus, Candida parapsilosis has been associated to candidaemia in neonates and young adults. This species usually has an exogenously origin and contaminates medical devices, causing central venous catheter-associated candidaemias. Candida glabrata, Candida tropicalis and Candida krusei are isolated in blood cultures from older patients (>65 years) with important risk factors, such as major abdominal surgery, solid tumours and haematologic malignancies, transplants, and/or prolonged treatment with corticoids. Moreover, important geographical differences in the distribution of the Candida species different to C. albicans causing invasive candidiasis have been reported: C. parapsilosis predominates in Australia, Latin America and Mediterranean countries of Africa, Asia and Europe. In contrast, C. glabrata has an important aetiological role in USA and Central and Northern Europe. Finally, an important and worrying issue is that mortality due to invasive candidiasis remains unacceptably high. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

Epidemiology and predictive factors for early and late mortality in Candida bloodstream infections: a population-based surveillance in Spain

A prospective, multicentre, population-based surveillance programme for Candida bloodstream infections was implemented in five metropolitan areas of Spain to determine its incidence and the prevalence of antifungal resistance, and to identify predictors of death. Between May 2010 and April 2011, Candida isolates were centralized to a reference laboratory for species identification by DNA sequencing and for susceptibility testing by EUCAST reference procedure. Prognostic factors associated with early (0-7 days) and late (8-30 days) death were analysed using logistic regression modelling. We detected 773 episodes: annual incidence of 8.1 cases/100 000 inhabitants, 0.89/1000 admissions and 1.36/10 000 patient-days. Highest incidence was found in infants younger than 1 year (96.4/100 000 inhabitants). Candida albicans was the predominant species (45.4%), followed by Candida parapsilosis (24.9%), Candida glabrata (13.4%) and Candida tropicalis (7.7%). Overall, 79% of Candida isolates were susceptible to fluconazole. Cumulative mortality at 7 and 30 days after the first episode of candidaemia was 12.8% and 30.6%, respectively. Multivariate analysis showed that therapeutic measures within the first 48 h may improve early mortality: antifungal treatment (OR 0.51, 95% CI 0.27-0.95) and central venous catheter removal (OR 0.43, 95% CI 0.21-0.87). Predictors of late death included host factors (e.g. patients' comorbid status and signs of organ dysfunction), primary source (OR 1.63, 95% CI 1.03-2.61), and severe sepsis or septic shock (OR 1.77, 95% CI 1.05-3.00). In Spain, the proportion of Candida isolates non-susceptible to fluconazole is higher than in previous reports. Early mortality may be improved with strict adherence to guidelines.

Candida dubliniensis encrustation of an obstructing upper renal tract calculus

We present the case of a 53-year-old man, with a history of alcohol abuse, requiring intensive care unit admission, with an obstructing right upper renal calculus and Klebsiella pneumoniae urosepsis. Ureteroscopic treatment of this obstruction displayed a small calculus within the renal pelvis completely encapsulated within a fungal bezoar. Laboratory analysis of the fungal mass found it to be Candida dubliniensis.

In vitro activities of isavuconazole and comparator antifungal agents tested against a global collection of opportunistic yeasts and molds

Isavuconazole is a new broad-spectrum triazole with a favorable pharmacokinetic and safety profile. We report the MIC distributions for isavuconazole and 111 isolates of Candida (42 Candida albicans, 25 Candida glabrata, 22 Candida parapsilosis, 14 Candida tropicalis, and 8 Candida krusei isolates), as determined by Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution (BMD) methods. Also, the relative activities of isavuconazole, itraconazole, fluconazole, posaconazole, voriconazole, and the three echinocandins were assessed against a recent (2011) global collection of 1,358 isolates of Candida spp., 101 of Aspergillus spp., 54 of non-Candida yeasts, and 21 of non-Aspergillus molds using CLSI BMD methods. The overall essential agreement (EA) (±2 log2 dilutions) between the CLSI and EUCAST methods was 99.1% (EA at ±1 log2 dilution, 90.1% [range, 80.0 to 100.0%]). The activities of isavuconazole against the larger collection of Candida spp. and Aspergillus spp. were comparable to those of posaconazole and voriconazole; the MIC90 values for isavuconazole, posaconazole, and voriconazole against Candida spp. were 0.5, 1, and 0.25 μg/ml and against Aspergillus spp. were 2, 1, and 1 μg/ml, respectively. Isavuconazole showed good activities against Cryptococcus neoformans (MIC90, 0.12 μg/ml) and other non-Candida yeasts (MIC90, 1 μg/ml) but was less potent against non-Aspergillus molds (MIC90, >8 μg/ml). Isavuconazole MIC values for three mucormycete isolates were 4, 1, and 2 μg/ml, whereas all three were inhibited by 1 μg/ml posaconazole. Isavuconazole demonstrates broad-spectrum activity against this global collection of opportunistic fungi, and the CLSI and EUCAST methods can be used to test this agent against Candida, with highly comparable results.

Surveillance study of species distribution, antifungal susceptibility and mortality of nosocomial candidemia in a tertiary care hospital in China

Background

Bloodstream infections due to Candida species cause significant morbidity and mortality, and the epidemiology of Candida infection is changing. Surveillance for candidemia is necessary to detect trends in species distribution and antifungal resistance.

Methods

The medical and electronic records of all patients who had candidemia at the authors’ hospital from 2009 to 2011 were reviewed for demographic data and clinical information, including the infecting Candida species, resistance to antifungals and survival, and the presence of risk factors associated with candidemia.

Results

A total of 133 distinct episodes of candidemia were identified over the study period. The annual incidence of candidemia ranged between 0.71 and 0.85 cases/1000 hospital discharges. The most frequent Candida species were C. tropicalis (28.6%), followed by C. albicans (23.3%) and C. parapsilosis (19.5%). The rates of susceptibility to antifungal agents were as followed: voriconazole (97.8%), itraconazole (69.5%), fluconazole (46.1%), ketoconazole (38.9%). Out of 131 evaluable patients, 34 (26.0%) died within 30 days from the onset of candidemia. C. tropicalis candidemia was associated with the highest mortality rate (44.7%). Regarding the crude mortality in the different units, patients in Hemato-Oncology ward had the highest mortality rate (66.7%), followed by patients in cardiovascular wards and ICU (57.1% and 25.6%, respectively). Predictors of 30-day mortality were identified by uni- and multivariate analyses. Complicated abdominal surgery, presence of central venous catheter (CVC), neutropenia, candidemia due to C. tropicalis and poor treatment with fluconazole were significantly associated with the 30-day mortality. Presence of CVC (odds ratio[OR] = 4.177; 95% confidence interval [CI] = 1.698 to 10.278; P = 0.002) was the only independent predictor for mortality in the multivariate analysis.

Conclusion

This report provides baseline data for future epidemiological and susceptibility studies and for the mortality rates associated with candidemia in our hospital. The knowledge of the local epidemiological trends in Candida species isolated in blood cultures is important to guide therapeutic choices.

The synthetic amphipathic peptidomimetic LTX109 is a potent fungicide that disturbs plasma membrane integrity in a sphingolipid dependent manner

The peptidomimetic LTX109 (arginine-tertbutyl tryptophan-arginine-phenylethan) was previously shown to have antibacterial properties. Here, we investigated the activity of this novel antimicrobial peptidomimetic on the yeast Saccharomyces cerevisiae. We found that LTX109 was an efficient fungicide that killed all viable cells in an exponentially growing population as well as a large proportion of cells in biofilm formed on an abiotic surface. LTX109 had similar killing kinetics to the membrane-permeabilizing fungicide amphotericin B, which led us to investigate the ability of LTX109 to disrupt plasma membrane integrity. S. cerevisiae cells exposed to a high concentration of LTX109 showed rapid release of potassium and amino acids, suggesting that LTX109 acted by destabilizing the plasma membrane. This was supported by the finding that cells were permeable to the fluorescent nucleic acid stain SYTOX Green after a few minutes of LTX109 treatment. We screened a haploid S. cerevisiae gene deletion library for mutants resistant to LTX109 to uncover potential molecular targets. Eight genes conferred LTX109 resistance when deleted and six were involved in the sphingolipid biosynthetic pathway (SUR1, SUR2, SKN1, IPT1, FEN1 and ORM2). The involvement of all of these genes in the biosynthetic pathway for the fungal-specific lipids mannosylinositol phosphorylceramide (MIPC) and mannosyl di-(inositol phosphoryl) ceramide (M(IP)2C) suggested that these lipids were essential for LTX109 sensitivity. Our observations are consistent with a model in which LTX109 kills S. cerevisiae by nonspecific destabilization of the plasma membrane through direct or indirect interaction with the sphingolipids.

Management of candidaemia and invasive candidiasis in critically ill patients

Critically ill patients in the intensive care unit (ICU) are at increased risk of encountering bloodstream infections (BSIs) with Candida spp., associated with an elevated crude mortality rate. This supports the significance of early detection of infection and identification of the most effective management approach. A review of the various antifungal treatments and an evaluation of the diverse management approaches for invasive candidiasis in critically ill patients is necessary for guiding evidence-based decision-making. Different early detection schemes for invasive candidiasis are well documented in the literature. Other than the common use of blood cultures, new methods entail the use of risk prediction scores and biomarker tests. Regarding management strategies, different options are currently supported. These include prophylaxis, empirical therapy, pre-emptive therapy, and treatment of culture-documented infections. The choice of treatment is greatly dependent on several factors related to the patient and/or to the surrounding environment. Attention needs to be given to previous exposure to azoles, epidemiological data on dominant Candida spp. in local ICUs, severity of illness and associated morbidities. This paper summarises the most recent literature as well as the guidelines issued by the Infectious Diseases Society of America. The objective is to identify the best diagnosis and management approaches for serious Candida infections in critically ill patients. In addition, this article addresses an important aspect associated with managing candidaemia in critically ill patients pertaining to the decision for intravenous catheter removal.

Endemic genotypes of Candida albicans causing fungemia are frequent in the hospital

Genotyping of Candida albicans strains causing candidemia can uncover the presence of endemic genotypes in the hospital. Using a highly reproducible and discriminatory microsatellite marker panel, we studied the genetic diversity of 217 C. albicans isolates from the blood cultures of 202 patients with candidemia (from January 2007 to December 2011). Each isolate represented 1 candidemia episode. Multiple episodes were defined as the isolation of C. albicans in further blood cultures taken ≥7 days after the last isolation in blood culture. Of the 202 patients, 188 had 1 episode, 13 had 2 episodes, and 1 had 3 episodes. Identical genotypes showed the same alleles for all 6 markers. The genotypes causing both episodes were identical in most patients with 2 episodes (11/13; 84.6%). In contrast, 2 different genotypes were found in the patient with 3 episodes, one causing the first and second episodes and the other causing the third episode (isolated 6 months later). We found marked genetic diversity in 174 different genotypes: 155 were unique, and 19 were endemic and formed 19 clusters (2 to 6 patients per cluster). Up to 25% of the patients were infected by endemic genotypes that infected 2 or more different patients. Some of these endemic genotypes were found in the same unit of the hospital, mainly neonatology, whereas others infected patients in different wards.

ESCMID* guideline for the diagnosis and management of Candida diseases 2012: diagnostic procedures

As the mortality associated with invasive Candida infections remains high, it is important to make optimal use of available diagnostic tools to initiate antifungal therapy as early as possible and to select the most appropriate antifungal drug. A panel of experts of the European Fungal Infection Study Group (EFISG) of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) undertook a data review and compiled guidelines for the clinical utility and accuracy of different diagnostic tests and procedures for detection of Candida infections. Recommendations about the microbiological investigation and detection of candidaemia, invasive candidiasis, chronic disseminated candidiasis, and oropharyngeal, oesophageal, and vaginal candidiasis were included. In addition, remarks about antifungal susceptibility testing and therapeutic drug monitoring were made.

Increasing echinocandin resistance in Candida glabrata: clinical failure correlates with presence of FKS mutations and elevated minimum inhibitory concentrations

BACKGROUND

Fluconazole (FLC) resistance is common in C. glabrata and echinocandins are often used as first-line therapy. Resistance to echinocandin therapy has been associated with FKS1 and FKS2 gene alterations.

METHODS

We reviewed records of all patients with C. glabrata bloodstream infection at Duke Hospital over the past decade (2001-2010) and correlated treatment outcome with minimum inhibitory concentration (MIC) results and the presence of FKS gene mutations. For each isolate, MICs to FLC and echinocandins (anidulafungin, caspofungin, and micafungin) and FKS1 and FKS2 gene sequences were determined.

RESULTS

Two hundred ninety-three episodes (313 isolates) of C. glabrata bloodstream infection were analyzed. Resistance to echinocandins increased from 4.9% to 12.3% and to FLC from 18% to 30% between 2001 and 2010, respectively. Among the 78 FLC resistant isolates, 14.1% were resistant to 1 or more echinocandin. Twenty-five (7.9%) isolates harbored a FKS mutation. The predictor of a FKS mutant strain was prior echinocandin therapy (stepwise multivariable analysis, odds ratio, 19.647 [95% confidence interval, 7.19-58.1]). Eighty percent (8/10) of patients infected with FKS mutants demonstrating intermediate or resistant MICs to an echinocandin and treated with an echinocandin failed to respond or responded initially but experienced a recurrence.

CONCLUSIONS

Echinocandin resistance is increasing, including among FLC-resistant isolates. The new Clinical and Laboratory Standards Institute clinical breakpoints differentiate wild-type from C. glabrata strains bearing clinically significant FKS1/FKS2 mutations. These observations underscore the importance of knowing the local epidemiology and resistance patterns for Candida within institutions and susceptibility testing of echinocandins for C. glabrata to guide therapeutic decision making.

A risk factor analysis of healthcare-associated fungal infections in an intensive care unit: a retrospective cohort study

Background

The incidence of fungal healthcare-associated infection (HAI) has increased in a major teaching hospital in the northern part of Taiwan over the past decade, especially in the intensive care units (ICUs). The purpose of this study was to determine the factors that were responsible for the outbreak and trend in the ICU.

Methods

Surveillance fungal cultures were obtained from “sterile” objects, antiseptic solutions, environment of infected patients and hands of medical personnel. Risk factors for comparison included age, gender, admission service, and total length of stay in the ICU, Acute Physiology and Chronic Health Evaluation (APACHE) II scores at admission to the ICU, main diagnosis on ICU admission, use of invasive devices, receipt of hemodialysis, total parenteral nutrition (TPN) use, history of antibiotic therapy before HAI or during ICU stay in no HAI group, and ICU discharge status (ie, dead or alive). Univariable analysis followed by multiple logistic regression analysis was performed to identify the independent risk factors for ICU fungal HAIs and ICU mortality.

Results

There was a significant trend in ICU fungal HAIs from 1998 to 2009 (P < 0.001). A total of 516 episodes of ICU fungal HAIs were identified; the rates of various infections were urinary tract infection (UTI) (54.8%), blood stream infection (BSI) (30.6%), surgical site infection (SSI) (6.6%), pneumonia (4.5%), other sites (3.5%). The fungi identified were: yeasts (54.8%), Candida albicans (27.3%), Candida tropicalis (6.6%), Candida glabrata (6.6%), Candida parapsilosis (1.9%), Candida species (0.8%), and other fungi (1.9%). Candida albicans accounted for 63% of all Candida species. Yeasts were found in the environment of more heavily infected patients. The independent risk factors (P < 0.05) of developing ICU fungal HAIs from all sites were TPN use, sepsis, surgical patients, mechanical ventilation and an indwelling urinary catheter. The independent risk factors for ICU fungal UTI included TPN use, mechanical ventilation and an indwelling urinary catheter. The independent risk factors for ICU fungal BSI included TPN use, sepsis, and higher APACHE II score. The independent risk factors for ICU fungal pneumonia included TPN use, surgical patients. The independent risk factors for ICU fungal SSI included surgical patients, and TPN use. The odds ratios of TPN use in various infection types ranged from 3.51 to 8.82. The risk of mortality in patients with ICU fungal HAIs was over 2 times that of patients without ICU HAIs in the multiple logistic regression analysis (P < 0.001).

Conclusions

There was a secular trend of an increasing number of fungal HAIs in our ICU over the past decade. Patients with ICU fungal HAIs had a significantly higher mortality rate than did patients without ICU HAIs. Total parenteral nutrition was a significant risk factor for all types of ICU fungal HAIs, and its use should be monitored closely.