Evaluation of candidemia and antifungal consumption in a large tertiary care Italian hospital over a 12-year period

Unveiling antifungal resistance and biocide tolerance in clinical isolates of Candida spp

AIMS

Candidiasis, caused by Candida spp. is an opportunistic infection with significant healthcare risks, worsened by trends in antifungal resistance. This study aimed to evaluate the antifungal susceptibility profile, investigate resistance mechanisms, assess efflux pump activity, and examine biocide tolerance in clinical Candida isolates.

METHODS

A total of 100 Candida isolates from hospitalized and outpatient individuals were analyzed for their antifungal susceptibility profile, molecular resistance mechanisms through PCR, efflux pump activity with the Cartwheel method, and biocide tolerance (sodium hypochlorite, hydrogen peroxide, and benzalkonium chloride), which was assessed by disk diffusion.

RESULTS

A high prevalence of resistance (87%) to at least one antifungal was observed, with 47.12% of isolates showing simultaneous multiple resistance to three azole derivatives. The highest antifungal agent resistance was observed for fluconazole (n = 70) and the highest susceptibility for amphotericin B (n = 1). The most common mutation was in the ERG11 gene (n = 38/43.7%). Efflux pump activity was detected in both C. albicans and non-albicans Candida species. Biocide testing revealed a higher tolerance for sodium hypochlorite, with an inhibition zone ranging from 18.25 (4.40) to 34.0 (4.00).

CONCLUSIONS

This study highlights significant antifungal resistance in Candida spp. particularly to azoles, stressing the need for improved infection control and novel therapeutic strategies.

Virulence and resistance factors of Nakaseomyces glabratus (formerly known as Candida glabrata) in Europe: A systematic review

BACKGROUND

Nakaseomyces glabratus (N. glabratus) formerly known as Candida glabrata (C. glabrata), is an endogenous opportunistic pathogen, which is generally located in the gastrointestinal tract but can spread in immunocompromised patients. N. glabratus is the second most common pathogen that causes candidemia in several countries. N. glabratus virulence factors may increase antifungal resistance and reduce the number of available treatment options. High resistance to azoles and increasing resistance to echinocandins have been previously reported in N. glabratus.

OBJECTIVE

To establish the distribution of N. glabratus isolates in Europe and its drug susceptibility/resistance in each country over the last 7 years.

METHODS

The search was performed across three databases: PubMed, Scopus and Scielo, using the MeSH terms: "Candida glabrata", "Nakaseomyces glabratus", "Europe", "resistance" and "Epidemiology" exclusively in English. All available information from January 2002 to December 2022 was included, excluding reviews, meta-analyses and book chapters.

RESULTS

Fifty-seven articles with information on antifungal susceptibility in Europe were retrieved and analysed with a total of 15,400 reported C. glabrata isolates. Remarkably, nations that presented the maximum number of cases during the study period included the United Kingdom (n = 7241, 47.02%), France (n = 3190, 20.71%), Spain (n = 900, 5.84%), Hungary (n = 745, 4.84%) and Italy (n = 486, 3.16%). C. glabrata isolates presented resistance to azoles [voriconazole (n = 2225, 14.45%), fluconazole (n = 1612, 10.47%), itraconazole (n = 337, 2.19%) and clotrimazole (n = 89, 0.58%)], increased resistance to echinocandins, especially to anidulafungin (n = 138, 0.89%), and high sensitivity to amphotericin B.

CONCLUSIONS

The number of candidemia cases associated with triazole-resistant N. glabratus isolates have been increasing in Europe. Therefore, echinocandins and amphotericin B can be considered optional empirical treatments; however, antifungal susceptibility testing is required to determine the best therapeutic options.

Comparative evaluation of antifungal susceptibility testing methods of invasive Candida species and detection of FKS genes mutations in caspofungin intermediate and resistant isolates

BACKGROUND

Fungal invasive infections caused by Candida species pose a substantial public health risk with limited therapeutic options. Antifungal susceptibility testing (AFST) is necessary to optimize the therapy. The study aimed to compare different AFST methods of Candida spp. and detect FKS gene mutations among caspofungin-intermediate and resistant isolates.

METHODS

A total of 60 non-replicative invasive Candida isolates recovered from various clinical samples were included. In-vitro AFST was carried out using the ATB FUNGUS 3, Vitek-2 AST-YS08, and E-test. Hotspot (HS) regions of FKS genes were sequenced for caspofungin-intermediate and resistant isolates.

RESULTS

Candida albicans (58.3%) was the most predominant spp., followed by C. glabrata (28.3%). Based on the clinical breakpoints (CBPs), fluconazole resistance was found in C. albicans (45.7%), C. tropicalis (25%), and the C. parapsilosis isolate, while 35.3% of C. glabrata were susceptible dose-dependent (SDD). None of C. albicans, C. tropicalis, or C. parapsilosis isolates were resistant to voriconazole. Using the epidemiological cut-off values (ECVs) for amphotericin B, 6.7% of isolates were non-wild type (non-WT), including C. guilliermondii (50%), C. tropicalis (25%), and C. glabrata (11.8%), while all C. albicans, C. parapsilosis, and C. kefyr isolates were classified as wild-type (WT). ATB FUNGUS 3 and Vitek-2 had the highest categorical agreement (CA) (83.1%) for amphotericin B, while a lower concordance was detected with voriconazole (23.2%) and fluconazole (52.2%). For caspofungin, Vitek-2 and E-test had a CA of 89.8%. Eleven isolates (10 C. glabrata and one C. parapsilosis) exhibited resistance or intermediate susceptibility to caspofungin (MICs: 0.25‒>32 µg/ml). Molecular characterization of the FKS gene demonstrated that FKS1 mutations V47I, V52K, V56T, D57S, L62F, I71Y, I71Q in the HS1 region, and G7S, P11H mutations in the HS2 region were associated with increased caspofungin MIC values (16 µg/ml). Mutations at the HS1 of the FKS2 gene; K33V, W35K, and W35V; were associated with the highest caspofungin MICs of > 32 µg/ml.

CONCLUSIONS

ATB FUNGUS 3 demonstrated acceptable performance for AFST, however, azole activity against Candida spp. should be interpreted carefully. Novel mutations within HS regions of FKS genes elucidated different levels of caspofungin resistance in C. glabrata and C. parapsilosis isolates.

Distribution and antifungal susceptibility profiles of Candida species isolated from candidemia patients admitted to Egyptian tertiary hospitals: a cross-sectional study

BACKGROUND

Candidemia is a widespread threat that can lead to significant complications in healthcare settings.

OBJECTIVES

Our study aimed to identify isolates of Candida isolated from blood culture bottles of patients with candidemia and assess their antifungal susceptibility profiles.

METHODS

We conducted a cross-sectional study at Cairo University tertiary care hospitals over 16 months including 90 patients. Candida isolates were collected from blood culture bottles, and identified using MALDI-TOF MS technology of VITEK MS PRIME (bioMérieux) with the corresponding database VITEK IVD Database 3.2. followed by antifungal susceptibility testing using VITEK 2 Compact system.

RESULTS

Candida albicans was the most common species isolated from both pediatric and adult patients with percentages of 47.3% and 36.4% respectively, followed by Candida parapsilosis with percentages of 32.6% and 25.0% respectively. Voriconazole showed the highest antifungal activity at 90.9% of isolates in adults and 95.7% in pediatrics, followed by caspofungin and micafungin. The mean hospital stays for adults ranged from 8 to 30 days and from 10 to 42 days in the pediatric group.

CONCLUSIONS

C. albicans remains the predominant species isolated from both pediatric and adult candidemia patients, despite a notable increase in other species. C. tropicalis and C. parapsilosis are considered the most common non-albicans Candida (NAC) species. The rise in Candida species other than albicans highlights the urgent need for effective antifungal stewardship programs. Voriconazole exhibited the higher antifungal activity followed by caspofungin and micafungin.

Antifungal susceptibility and virulence determinants profile of candida species isolated from patients with candidemia

Candida is the most prevalent fungal bloodstream infection (BSI) with a high mortality rate among hospitalized patients. Another concern facing physicians is rising global incidence of drug-resistant Candida. This study aimed to characterize the prevalence, antifungal susceptibility, biofilm formation, and virulence genes (HWP1, ALS1, SAP2) of different Candida spp. isolated from patients with candidemia. 52 isolates of Candida spp. were identified from blood cultures by chromogenic Candida agar and confirmed by the VITEK 2 system. Isolates were tested for antifungal susceptibility by disk diffusion and VITEK 2 system. Biofilm formation and investigated genes were detected by the Congo red method and conventional PCR, respectively. Candida spp. caused 2.3% of detected BSIs, of which 32.7% were caused by Candida albicans (C. albicans) and 67.3% by non-albicans Candida (NAC), with the predominance of C. tropicalis (25%), followed by C. parapsilosis (17.3%), and C. krusei (13.5%). The susceptibility rates to fluconazole, voriconazole, caspofungin, micafungin, amphotericin B, and flucytosine were 64.7%, 76.5%, 100.0%, 100%, 100.0%, and 100.0% in C. albicans, while 53.6%, 71.4%, 91.4%, 91.4%, 94.3%, and 94.3% in NAC, respectively. Biofilm production, HWP1, ALS1, and SAP2 were detected in 70.6%, 82.4%, 76.5%, and 52.9% of C. albicans and 74.3%, 85.7%, 80.0%, and 48.6% of NAC, respectively. There is remarkable shift to NAC BSIs and high azole resistance. Antifungal stewardship and analysis of risk factors associated with this shift are needed.

Outbreak of Candida parapsilosis fungemia in an intensive care unit during a COVID surge: an epidemic within a pandemic

We sought to investigate epidemiology, risk factors, clinical features, and outcome of the C. parapsilosis blood stream infection (BSI) outbreaks observed during the first surges of COVID-19 pandemic in our population. Retrospective, monocentric observational study in the 24 bed intensive care unit (ICU) of a tertiary care medical center in northern Italy, from 2019 to 2021 first 5 months. 2030 patients were enrolled, of whom 239 were COVID-19 positive. The total incidence of Candida-BSI was 41.9 per 1000 admissions, with two outbreaks during 2020 spring and winter's COVID surges. The total numbers of C. parapsilosis BSI cases are 94, of which 21 during the first outbreak and 20 during the second. In our population, COVID-19 was strongly associated with C. parapsilosis BSI (OR 4.71, p < 0.001), as well as continuous renal replacement therapy (CRRT) (OR 3.44, p = 0.001), prolonged antibiotic therapy (OR 3.19, p = 0.004), and delayed infusion sets replacements (OR 2.76, p = 0.015). No statistically significant association was found between Candida-BSI episodes and mortality, when adjusted for other known outcome risk factors. COVID surges undermined the infectious control measures in our ICU, leading to two outbreak of C. parapsilosis BSI. A stricter, thorough management of intravascular devices and infusion set is crucial in prevention of catheter related BSI, and awareness must be kept high, especially in emergencies circumstances, such as the ongoing COVID-19 pandemic.

Simultaneous Analysis of Bacterial and Fungal Communities in Oral Samples from Intubated Patients in Intensive Care Unit

Intubated patients in intensive care units (ICUs) too frequently contract ventilator-associated pneumonia or Candida infections. Oropharyngeal microbes are believed to play an important etiologic role. This study was undertaken to determine whether next-generation sequencing (NGS) can be used to simultaneously analyze bacterial and fungal communities. Buccal samples were collected from intubated ICU patients. Primers targeting the V1-V2 region of bacterial 16S rRNA and the internal transcribed spacer 2 (ITS2) region of fungal 18S rRNA were used. V1-V2, ITS2, or mixed V1-V2/ITS2 primers were used to prepare an NGS library. Bacterial and fungal relative abundances were comparable for V1-V2, ITS2, or mixed V1-V2/ITS2 primers, respectively. A standard microbial community was used to adjust the relative abundances to theoretical abundance, and NGS and RT-PCR-adjusted relative abundances showed a high correlation. Using mixed V1-V2/ITS2 primers, bacterial and fungal abundances were simultaneously determined. The constructed microbiome network revealed novel interkingdom and intrakingdom interactions, and the simultaneous detection of bacterial and fungal communities using mixed V1-V2/ITS2 primers enabled analysis across two kingdoms. This study provides a novel approach to simultaneously determining bacterial and fungal communities using mixed V1-V2/ITS2 primers.

Prevalence and species distribution of Candida bloodstream infection in children and adults in two teaching university hospitals in Egypt: first report of Candida kefyr

BACKGROUND

Candidemia is a pervasive problem associated with significant morbidity and mortality in health care settings. This study aimed to determine the changing distribution of Candida species and the emergence of uncommon species.

METHODS

This was a cross-sectional study performed in two Cairo University hospitals between 2019 and 2020. All Candida species isolates recovered from blood cultures of adults and pediatrics patients admitted to the hospitals were included. Candida isolates were identified by chromogenic Candida agar and Vitek2 YST identification card. Candida kefyr was confirmed by chip array.

RESULTS

Candida species were responsible for 1.6% of bloodstream infections in adults and 10.8% in pediatric patients. C. albicans was the most prevalent species representing 27.8% in adults and 48.3% in pediatrics. Non-albicans species (NAC) represented the most isolated Candida species among adults and pediatrics (72.2% and 51.6%, respectively) with the predominance of C. tropicalis (27.8% and 22.5%, respectively) followed by C. parapsilosis (16.7% and 10.8%, respectively). The uncommon Candida, which is Candida species other than C. albicans, C. parapsilosis, C. tropicalis, C. glabrata, and C. krusei, represents 16.6% and 14% of all candidemia in adults and pediatrics, respectively. Only one of each of C. lusitaniae, C. utilis, and C. kefyr were detected in adults. C. lusitaniae was the most frequently recovered uncommon Candida among pediatrics resulting in 6.4% of candidemia followed by C. famata (4.3%), C. utilis (2.2%), and C. kefyr (1.1%).

CONCLUSIONS

C. albicans is still the primary species isolated from pediatrics and adults with candidemia despite the considerable shift to the non-albicans species. C. tropicalis and C. parapsilosis are the most prevalent NAC. The increased prevalence of uncommon Candida species is alarming and necessitates a prompt stewardship program.

Utilization Trends of Antiviral and Antifungal Agents for Human Systemic Use in Tanzania From 2010 to 2017 Using the World Health Organization Collaborating Centre for Drug Statistics Methodology

Introduction

The increase in antimicrobial consumption contributes to the emergence of antimicrobial resistance (AMR). Many studies have investigated the patterns of antibacterial consumption and antibacterial resistance. However, there is a paucity of data on the utilization of antivirals and antifungals in low and middle-income countries to serve as a baseline for monitoring and surveillance of AMR. Therefore, this study determined Tanzania’s systemic antifungal and antiviral utilization trends from 2010 to 2017, based on the Tanzania Medicines and Medical Devices Authority (TMDA) medicine importation archives.

Methodology

An analytical, longitudinal retrospective survey covering 2010 to 2017 was conducted. The study utilized the Anatomical Therapeutic and Chemical (ATC) classification and Defined Daily Dose (DDD) developed by the World Health Organization (WHO) Collaborating Centre for Drug Statistics and the WHO Collaboration Centre for International Drug Consumption Monitoring. Human medicine importation data were collected from TMDA headquarters and used to assess the systemic antiviral and antifungal consumption trends. The importation data included the date, generic name, strength, brand name, currency, quantity, ATC classification, supplier country, port of entry and product supplier. The data were cleaned, reorganized and analyzed. Reference was made to the latest revised DDD list to assign antifungals and antivirals to their respective ATC/DDDs and then adjusted to the population estimates from the National Bureau of Statistics of Tanzania.

Results

There was a high proportion of systemic antivirals and antifungals utilization with 367.1 and 10.8 DDD per 1000 inhabitants per day (DID) respectively over eight years. In regression model, there was a significant increase in both antiviral (p-value = 0.043) and antifungal (p-value = 0.015) agents’ utilization trends in Tanzania in the study period. Fluconazole had the highest proportion of utilization for antifungals, followed by ketoconazole, itraconazole, miconazole and amphotericin B. For systemic antivirals, a high proportion was attributed to antiretrovirals used for HIV infections.

Conclusion

Findings from this study suggest an increase in the utilization of systemic antiviral and antifungal agents. These findings may be used to further benchmark utilization and AMR studies in Tanzania.

Emerging issue of fluconazole-resistant candidemia in a tertiary care hospital of southern italy: time for antifungal stewardship program

An increased number of patients is at risk of Candida spp. bloodstream infection (CBSI) in modern medicine. Moreover, the rising of antifungal resistance (AR) was recently reported. All consecutive CBSI occurred in our Hospital (consisting of 1,370 beds) between 2015 and 2018, were reviewed. For each case, Candida species, AR pattern, ward involved and demographic data of patients were recorded. Overall, 304 episodes of CBSI occurred, with a median (q1:first-,q3:third quartile) of 77 (71-82) CBSI/year. Over the years, a significant increase of CBSI due to C. albicans compared to non-albicans strains was recorded in medical wards (from 65% to 71%, p=0.030), while this ratio remained stable in others. An increase of resistant strains to multiple antifungals such as C. guillermondii was noticed in recent years (from 0% to 9.8%, p=0.008). Additionally, from 2015 to 2018 an increase in fluconazole-resistance was recorded in our Hospital (from 7.4% to 17.4%, p=0.025) and a slight increase in voriconazole-resistance (from 0% to 7% in 2018, p=0.161) was observed, while resistance to echinocandin and amphotericin B remained firmly below 2%. This study suggests a rapid spread of antifungal resistance in our Hospital; therefore, an appropriate antifungal stewardship programs is urgently warranted.

Factors associated with the development of ocular candidiasis and ocular prognosis with echinocandin therapy for candidemia

Purpose

To evaluate the factors associated with the development of ocular candidiasis (OC) and ocular prognosis with echinocandin therapy for candidemia.

Methods

The medical records of 56 consecutive patients with a positive blood culture for Candida species between November 2016 and October 2019 were retrospectively reviewed. Information on patient characteristics, isolated Candida species, treatment details for candidemia, and ocular findings were extracted to identify factors associated with OC development.

Results

The leading pathogen of candidemia was Candida albicans (C.albicans) (41.1%). Of 56 patients, 18 (32.1%) were diagnosed with chorioretinitis, categorized as either probable (8 patients) or possible OC (10 patients). There was no case of endophthalmitis with vitritis. The incidence of probable OC was not significantly different between the groups treated with echinocandins and other antifungal drugs (15.2% vs. 11.1%, p = 1.00). In all probable OC cases, systemic antifungal therapy was switched from echinocandins to azoles, and no case progressed to endophthalmitis. A multivariate logistic analysis revealed that female sex (adjusted odds ratio [aOR], 8.93; 95% confidence interval [CI], 1.09–72.9) and C. albicans (aOR, 23.6; 95% CI, 1.8–281) were independent factors associated with the development of probable OC.

Conclusion

One-seventh of patients with candidemia developed probable OC. Given the evidence of female and C. albicans as the factors associated with OC development, careful ophthalmologic management is required with these factors, especially in candidemia. Although echinocandins had no correlation with OC development and did not lead to the deterioration of ocular prognosis, further investigation is required.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12348-021-00248-0.

Trends in the Epidemiology of Candidemia in Intensive Care Units From 2006 to 2017: Results From the Korean National Healthcare-Associated Infections Surveillance System

Candidemia is an important healthcare-associated infection (HAI) in intensive care units (ICUs). However, limited research has been conducted on candidemia in the Republic of Korea. We aimed to analyze the secular trends in the incidence and distribution of candidemia in ICUs over 12-years using data from the Korean National Healthcare-Associated Infections Surveillance System (KONIS). KONIS was established in 2006 and has performed prospective surveillance of HAIs including bloodstream infections (BSIs) in ICUs. We evaluated the trends in the distribution of causative pathogens and the incidence of candidemia. From 2006 to 2017, 2,248 candidemia cases occurred in 9,184,264 patient-days (PDs). The pooled mean incidence rates of candidemia significantly decreased from 3.05 cases/10,000 PDs in 2006 to 2.5 cases/10,000 PDs in 2017 (P = 0.001). Nevertheless, the proportion of candidemia gradually increased from 15.2% in 2006 to 16.6% in 2017 (P = 0.001). The most frequent causative pathogen of BSIs from 2006 to 2012 was Staphylococcus aureus; however, Candida spp. emerged as the most frequent causative pathogen since 2013. C. albicans (39.9%) was the most common among Candida spp. causing BSIs, followed by Candida tropicalis (20.2%) and Candida parapsilosis (18.2%). The proportion of candidemia caused by C. glabrata significantly increased from 8.9% in 2006 to 17.9% in 2017 (P < 0.001). There was no significant change in the distribution of Candida spp. by year (P = 0.285). The most common source of BSIs was central lines associated BSI (92.5%). There was a significant increase in the proportion of candidemia by year in hospitals with organ transplant wards (from 18.9% in 2006 to 21.1% in 2017, P = 0.003), hospitals with <500 beds (from 2.7% in 2006 to 13.6% in 2017, P < 0.001), and surgical ICUs (from 16.2% in 2006 to 21.7% in 2017, P = 0.003). The proportion of candidemia has increased in Korea, especially in hospitals with <500 beds and surgical ICUs. Thus, appropriate infection control programs are needed.

Resistance to echinocandin antifungal agents in the United Kingdom in clinical isolates of Candida glabrata: Fifteen years of interpretation and assessment

Candidemia is widely reported as the fourth most common form of bloodstream infection worldwide. Reports of breakthrough cases of candidemia are increasing, especially in the context of a move away from azole antifungals as prophylactic or first line treatment toward the use of echinocandin agents. The global evaluation of echinocandin antifungal susceptibility since 2003 has included switches in testing methodologies and the move to a sentinel echinocandin approach for classification reporting. This study compiles previously unpublished data from echinocandin susceptibility testing of UK clinical isolates of C. glabrata received at the Public Health England Mycology Reference Laboratory from 2003 to 2016 and reevaluates the prevalence of resistance in light of currently accepted testing protocols. From 2015 onward, FKS gene mutation detection using a novel Pyrosequencing® assay was assessed as a predictor of echinocandin resistance alongside conventional susceptibility testing. Overall, our data show that echinocandin resistance in UK isolates of C. glabrata is a rare phenomenon and prevalence has not appreciably increased in the last 14 years. The pyrosequencing assay was able to successfully detect hot spot mutations in FKS1 and FKS2, although not all isolates that exhibited phenotypic resistance demonstrated detectable hot spot mutations. We propose that a rapid genomic based detection method for FKS mutations, as part of a multifactorial approach to susceptibility testing, could help provide accurate and timely management decisions especially in regions where echinocandin resistance has been reported to be emerging in this important pathogen.

Anidulafungin Versus Micafungin in the Treatment of Candidemia in Adult Patients

Background

Echinocandins are recommended for the treatment of invasive candidiasis and candidemia. However, there are few studies comparing anidulafungin and micafungin in terms of efficacy and safety. The objective of this study was to evaluate the clinical efficacy and safety between anidulafungin and micafungin treatment for adult patients with candidemia.

Methods

This retrospective cohort study performed on adult candidemia patients diagnosed from January 2006 through December 2018 at a tertiary medical center. The study subjects included adult patients ≥ 19 years with candidemia who were only treated with anidulafungin or micafungin for ≥ 3 days. Clinical characteristics were collected and analyzed. Hepatotoxicity was assessed according to the Common Terminology Criteria for Adverse Events Version 5.0.

Results

A total of 98 patients with candidemia were treated with anidulafungin (n = 52, 53.1%) or micafungin (n = 46, 46.9%). There were no significant differences in age, sex, source of candidemia, and comorbidities between the anidulafungin and micafungin groups. Although there were more patients with abnormal baseline liver function test (LFT) in the anidulafungin group, the rate of clinical response (51.9% vs. 46.7%), mycological response (76.9% vs. 67.4%), and mortality (30-day mortality 26.9% vs. 21.7% and 90-day mortality 78.8% vs. 73.9%) was similar between the anidulafungin and micafungin groups. Also, there was no significant difference in terms of hepatotoxicity, even among the patients with abnormal baseline LFT between the two groups.

Conclusions

Our results suggest that clinical efficacy and safety may be similar between anidulafungin and micafungin treatment for adult patients with candidemia.

Electronic supplementary material

The online version of this article (10.1007/s11046-020-00471-8) contains supplementary material, which is available to authorized users.

Candida blood stream infections observed between 2011 and 2016 in a large Italian University Hospital: A time-based retrospective analysis on epidemiology, biofilm production, antifungal agents consumption and drug-susceptibility

Candida bloodstream infection (BSI) represents a growing infective problem frequently associated to biofilm production due to the utilization of intravascular devices. Candida species distribution (n = 612 strains), their biofilm production and hospital antifungal drug consumption were evaluated in different wards of a tertiary care academic hospital in Italy during the years 2011–2016. In the considered time window, an increasing number of Candida BSI (p = 0.005) and of biofilm producing strains were observed (p<0.0001). Although C. albicans was the species more frequently isolated in BSI with a major biofilm production, an increased involvement of non-albicans species was reported, particularly of C. parapsilosis that displayed a high frequency in catheter infections, and lower biofilm production compared to C. albicans. Although trends of biofilm production were substantially stable in time, a decreasing biofilm production by C. parapsilosis in the Intensive Care Unit (ICU) was observed (p = 0.0041). Principal component analysis displayed a change in antifungal drugs consumption driven by two mutually independent temporal trends, i.e. voriconazole use in the general medicine wards initially, and fluconazole use mainly in the ICU; these factors explain 68.9% and 25.7% of total variance respectively. Moreover, a significant trend (p = 0.003) in fluconazole use during the whole time period considered emerged, particularly in the ICU (p = 0.017), but also in the general medicine wards (p = 0.03). These trends paralleled with significant increase MIC90 of fluconazole (p = 0.05), particularly for C. parapsilosis in the ICU (p = 0.04), with a general and significant decreased trend of the MIC90 values of caspofungin (p = 0.04), and with significant increased MIC50 values for amphotericin B (p = 0.01) over the study period. In conclusion, drug utilization in our hospital turned out to be a putative influencing factor on the ecology of the species, on the increase in time of the biofilm producing strains and on the Candida antifungal susceptibility profile, thus influencing clinical management.

Surveillance study of the prevalence, species distribution, antifungal susceptibility, risk factors and mortality of invasive candidiasis in a tertiary teaching hospital in Southwest China

BACKGROUND

Invasive candidiasis (IC) is the most common invasive fungal infection. The epidemiology of IC in hospitalized patients has been widely investigated in many metropolitan cities; however, little information from medium and small cities is known.

METHODS

A 5-year retrospective study was carried out to analyze the prevalence, species distribution, antifungal susceptibility, risk factors and mortality of inpatients with invasive Candida infection in a regional tertiary teaching hospital in Southwest China.

RESULTS

A total of 243 inpatients with invasive Candida infection during the five-year study period were identified, with a mean annual incidence of 0.41 cases per 1000 admissions and a 30-day mortality rate of 12.3%. The species distributions of Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, Candida parapsilosis and other Candida species was 45.3, 30.0, 15.2, 4.9, 2.1 and 2.5%, respectively. The total resistance rates of fluconazole (FCA), itraconazole (ITR) and voriconazole (VRC) were 18.6, 23.1 and 18.5%, respectively. Respiratory dysfunction, pulmonary infection, cardiovascular disease, chronic/acute renal failure, mechanical ventilation, abdominal surgery, intensive care in adults, septic shock and IC due to C. albicans were associated with 30-day mortality (P < 0.05) according to the univariate analyses. Respiratory dysfunction [odds ratio (OR), 9.80; 95% confidence interval (CI), 3.24-29.63; P < 0.001] and IC due to C. albicans (OR, 3.35; 95% CI, 1.13-9.92; P = 0.029) were the independent predictors of 30-day mortality.

CONCLUSIONS

This report shows that the incidence and mortality rates are lower and that the resistance rates to azoles are higher in medium and small cities than in large cities and that the species distributions and risk factors in medium and small cities are different from those in large cities in China. It is necessary to conduct epidemiological surveillance in medium and small cities to provide reference data for the surveillance of inpatients with IC infections.

Retrospective evaluation of candidemic patients among general surgery department in a tertiary care university hospital

OBJECTIVES

Candida species are among the most important causes of hospital acquired blood borne infections, and with high rates of mortality and morbidity, these infections are still a major problem today. History of gastrointestinal surgery, administration of total parenteral nutrition and/or wide spectrum antibiotics and immune suppression following organ transplantations are considered serious risk factors for these infections. This study aimed to evaluate the patients from our general surgery department with diagnosed candidemia; by means of strain, treatment and prognosis.

MATERIAL AND METHODS

Patients with positive blood cultures for Candida species who were treated in the wards and Ege University Faculty of Medicine general surgery department of surgical intensive care units of our between 2012 and 2017 were retrospectively analyzed by means of strain, treatment and prognosis.

RESULTS

A total of 50 patients were enrolled in the study. Mean age was 58.96 years and 54% of the patients were female. There were nine patients with organ transplantation (four liver and five kidney transplantations), six with intestinal perforation and three with anastomotic leakage. Isolated strains were Candida albicans (36%; 18/50), Candida tropicalis (14%; 7/50), Candida glabrata (12%; 6/50), Candida parapsilosis (8%; 4/50), Candida kefyr (6%; 3/50), Candida krusei (4%; 2/50), Candida pulcherrima (2%; 1/50), Cryptococcus neoformans (2%, 1/50), Geotrichum capitatum (2%, 1/50), Candida spp. (unidentified, 14%; 7/50) with decreasing frequency. The highest antifungal sensitivity rates (> 90%) were measured for amphotericin B, voriconazole and echinocandins among all isolates. One-month mortality rate was 43.4% (20/46). Documented eradication was achieved among 24 of the 33 patients who had control blood culture samples (72.7%), and mean eradication time was 7.6 days. Echocardiography was performed in 14% (7/50) and ophthalmic examination in 8% (4/50).

CONCLUSION

Although C. albicans appears to be the dominant strain in patients with candidemia, frequencies of other strains are increasing. Early diagnosis and treatment of patients with candidemia is of vital importance due to high mortality and morbidity rates.

Mating genotypes and susceptibility profiles of clinical isolates of Candida glabrata from Turkey

The sexual cycle of Candida glabrata is not known; however, genomic evidence is indicative of recombination among subpopulations and the genome harbours genes necessary for undergoing mating and meiosis, which may increase fitness. The relationship between specific mating type-like (MTL) loci and antifungal susceptibility is not well understood in C. glabrata. We investigated different combinations of clinical C. glabrata isolate mating types and their antifungal susceptibility profiles. Allele profiles of the mating genes of 103 clinical C. glabrata isolates were identified, and their antifungal susceptibility to azoles, echinocandins and amphotericin B were compared. The majority (88.3%) of screened isolates harboured the a allele in the locus. The MTL1, MTL2 and MTL3 loci harboured a (88.3%), a (95.1%), and α (71.8%) alleles, respectively. The C. glabrata isolates were susceptible to echinocandins but displayed high minimal inhibitory concentrations (MICs) for azoles. The MIC ranges and MIC90 values of all isolates were 1.0 to ≥64 and 8.0 μg mL^-1 for fluconazole, 0.06 to ≥16.0 and 0.5 μg mL^-1 for voriconazole, 0.06 to ≥16.0 and 1.0 μg mL^-1 for posaconazole, ≤0.015 to 0.06, and 0.03 μg mL^-1 for caspofungin, ≤0.015 to 0.06 and 0.015 μg mL^-1 for anidulafungin and 0.5-2 and 2.0 μg mL^-1 for amphotericin B, respectively. The mating gene alleles of the clinical C. glabrata isolates were not associated with differences in the MICs of the tested antifungals, except for the MTL3 α-allele and echinocandins. The mating genotypes of the clinical C. glabrata isolates had no recognisable common effect on antifungal susceptibility.