Strategies to Reduce Mortality in Adult and Neonatal Candidemia in Developing Countries

Prevalence and Species Distribution of Neonatal Candidiasis: A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

Candida infection is a significant cause of morbidity and mortality in neonatal intensive care units (NICU) globally. We aimed to conduct a systematic review to investigate the prevalence of candida among causative organisms of neonatal sepsis and identify the distribution of candida species infecting Saudi neonates.

METHODS

We comprehensively searched Web of Science, Scopus, PubMed, and Cochrane Library from their inception till November 2023. After screening titles, abstracts, and full texts, we ultimately included 21 eligible studies. The designs of the included studies were randomized clinical trials, cohorts, case-control, and case reports; the methodological quality was appraised using the Cochrane risk of bias assessment tool, NIH tool for observational studies, and Murad tool for assessing case reports.

RESULTS

Our systematic review and meta-analysis pooled data reported in 21 studies in the Saudi populations, which provided data on different types of candidal infections in 2346 neonates. The pooled data of ten retrospective studies enrolling 1823 neonates revealed that candida species resembled 4.2% of the causative organisms of neonatal sepsis among Saudi neonates (95%CI [2.5%; 5.9%], p = 0.000). Additionally, out of a total of 402 candida species that were identified among the included studies, C. albicans prevailed mostly among Saudi neonates, followed by C. parapsilosis, NS candida, and C. tropicalis (50.25%, 21.40%, 12.44%, and 9.45%, respectively).

CONCLUSIONS

We found that candida species prevailed in 4.2% of 1823 cases of neonatal sepsis; the most common candida species was C. albicans. We could not pool data regarding risk factors or susceptibility of candida species to different treatment modalities due to insufficient data, requiring future large-scale, high-quality studies to be conducted.

Pichia kudriavzevii (Candida krusei): A systematic review to inform the World Health Organisation priority list of fungal pathogens

In response to the growing global threat of fungal infections, in 2020 the World Health Organisation (WHO) established an Expert Group to identify priority fungi and develop the first WHO fungal priority pathogen list (FPPL). The aim of this systematic review was to evaluate the features and global impact of invasive infections caused by Pichia kudriavzevii (formerly known as Candida krusei). PubMed and Web of Science were used to identify studies published between 1 January 2011 and 18 February 2021 reporting on the criteria of mortality, morbidity (defined as hospitalisation and length of stay), drug resistance, preventability, yearly incidence, and distribution/emergence. Overall, 33 studies were evaluated. Mortality rates of up to 67% in adults were reported. Despite the intrinsic resistance of P. kudriavzevii to fluconazole with decreased susceptibility to amphotericin B, resistance (or non-wild-type rate) to other azoles and echinocandins was low, ranging between 0 and 5%. Risk factors for developing P. kudriavzevii infections included low birth weight, prior use of antibiotics/antifungals, and an underlying diagnosis of gastrointestinal disease or cancer. The incidence of infections caused by P. kudriavzevii is generally low (∼5% of all Candida-like blood isolates) and stable over the 10-year timeframe, although additional surveillance data are needed. Strategies targeting the identified risk factors for developing P. kudriavzevii infections should be developed and tested for effectiveness and feasibility of implementation. Studies presenting data on epidemiology and susceptibility of P. kudriavzevii were scarce, especially in low- and middle-income countries (LMICs). Thus, global surveillance systems are required to monitor the incidence, susceptibility, and morbidity of P. kudriavzevii invasive infections to inform diagnosis and treatment. Timely species-level identification and susceptibility testing should be conducted to reduce the high mortality and limit the spread of P. kudriavzevii in healthcare facilities.

Candida auris-a systematic review to inform the world health organization fungal priority pathogens list

The World Health Organization (WHO) in 2022 developed a fungal priority pathogen list. Candida auris was ultimately ranked as a critical priority pathogen. PubMed and Web of Science were used to find studies published from 1 January 2011 to 18 February 2021, reporting on predefined criteria including: mortality, morbidity (i.e., hospitalization and disability), drug resistance, preventability, yearly incidence, and distribution/emergence. Thirty-seven studies were included in the final analysis. The overall and 30-day mortality rates associated with C. auris candidaemia ranged from 29% to 62% and 23% to 67%, respectively. The median length of hospital stay was 46-68 days, ranging up to 140 days. Late-onset complications of C. auris candidaemia included metastatic septic complications. Resistance rates to fluconazole were as high as 87%-100%. Susceptibility to isavuconazole, itraconazole, and posaconazole varied with MIC90 values of 0.06-1.0 mg/l. Resistance rates to voriconazole ranged widely from 28% to 98%. Resistance rates ranged between 8% and 35% for amphotericin B and 0%-8% for echinocandins. Over the last ten years, outbreaks due to C. auris have been reported in in all WHO regions. Given the outbreak potential of C. auris, the emergence and spread of MDR strains, and the challenges associated with its identification, and eradication of its environmental sources in healthcare settings, prevention and control measures based on the identified risk factors should be evaluated for their effectiveness and feasibility. Global surveillance studies could better inform the incidence rates and distribution patterns to evaluate the global burden of C. auris infections.

Guideline Adherence and Outcomes of Patients with Candidemia in Brazil

Candidemia is a significant cause of mortality among hospitalized patients, both worldwide and in Brazil. Prompt and appropriate treatment are essential to mitigate mortality, and clinical practice guidelines aim to optimize patient care based on the best scientific evidence. This study aims to examine the management of candidemia, assessing adherence to the guidelines of the Brazilian Society of Infectious Diseases in a single center located at São Paulo, Brazil. All adult patients hospitalized from 2016 to 2018 who presented one positive blood culture for Candida spp. were included. Electronic medical records were retrospectively reviewed to collect information relevant to the treatment for candidemia, in order to assess the adherence to the Brazilian guideline for the management of candidemia in relation to nine defined outcomes, and we correlated those findings with 30-day mortality by using uni- and multivariate analyses. A total of 115 patients were included; 68 patients (59.1%) were male, with a mean age of 55 years. C. albicans, C. tropicalis and C. glabrata were the most prevalent species. In total, 80 patients (69.5%) received antifungal treatment. The adherence to Brazilian guideline recommendations was determined as described in the following: initial treatment with echinocandin in 48 (60%); step-down to fluconazole in 21 (26.2%); collection of first control blood culture in 43 (58.9%); collection of second control blood culture, if the first one had been positive, in 14 (73.6%); treatment for 14 days after the first negative blood culture in 53 (65.4%); central venous catheter (CVC) removal in 66 (82.5%); CVC removal if the first control blood culture had been positive in 17 (89.4%); performance of a transthoracic echocardiogram in 51 (63.7%) and performance of a fundoscopy in 59 (73.7%). Univariate analysis showed that CVC removal and initial echinocandin therapy were more prevalent in the surviving group, but with no statistically significant difference. On the other hand, step-down to fluconazole demonstrated higher survival rate in the multivariate analysis OR 0.15 (95% CI 0.03-0.8); p = 0.02. The analysis of these nine recommendations demonstrates that it is necessary to improve adherence to specific recommendations and also disseminate strategies of the initial use of echinocandin as the drug of choice and addressing length of treatment and follow-up and complementary exams. Our study provides reassurance that the step-down to fluconazole is safe and may be recommended, if the preexisting conditions are present.

Epidemiological Assessment and Risk Factors for Mortality of Bloodstream Infections by Candida sp. and the Impact of the COVID-19 Pandemic Era

Candidemia is one of the healthcare-associated infections that has high mortality. The risk factors that predispose a patient to develop this infection are mostly found in patients of greater severity and COVID-19 contributes to the risk of death. The aim of this study is to evaluate epidemiological characteristics and risk factors for mortality in patients with candidemia before and during the COVID-19 pandemic era. This is a retrospective study conducted at Instituto Central from 2016 to 2020 of patients with candidemia that were evaluated for demographic data, medical history, risk factors, microbiological data, therapeutic measures, complementary exams, device management, and outcome defined by 30-day mortality. A total of 170 episodes were included (58.2% males; mean age of 56 years). The overall incidence density of candidemia per 1000 admissions and per 1000 patient-days was 1.17 and 0.17, respectively, with an increase of 38% in the year 2020. The use of a central venous catheter was the most prevalent (93.5%) condition, followed by the previous use of antibiotics (91.1%). Corticosteroid use ranked seventh (56.4%). C. albicans was responsible for 71 (41.7%) of the isolates, followed by C. tropicalis and C. glabrata, with 34 (20%) isolates each. Echinocandin was prescribed in 60.1% of cases and fluconazole in 37%. Echocardiography resulted in six (5.08%) cases of endocarditis and fundoscopy resulting in two (2.4%) endophthalmitis. The 30-day mortality was 93/170 (54.7%). The risk factors associated with mortality were age (OR 1.03, CI 95% 1.01-1.06), heart disease (OR 7.51, CI 95% 1.48-37.9), hemodialysis (OR 3.68, CI 95% 1.28-10.57), and use of corticosteroids (OR 2.83, CI 95% 1.01-7.92). The COVID-19 pandemic had an impact on the increase incidence of candidemia. The persistently high mortality highlights the need for better management strategies, control of risk factors, and guarantee of adequate treatment.

Natural history and prognostic factors of candidemia in kidney transplant recipients: A retrospective, multinational study

BACKGROUND

The natural history of candidemia in kidney transplant recipients (KTR) remains poorly understood. This study aimed to evaluate mortality, prognostic factors and overall graft loss after candidemia in KTRs.

METHODS

This is a retrospective multicentre study enrolling all KTRs ≥15 years old with candidemia diagnosed at hospitals in Brazil, Spain and Italy from 2010 to 2020. Primary endpoints were mortality rates at 14 and 30 days. Secondary endpoints were prognostic factors of 14-day mortality and overall graft loss.

RESULTS

We enrolled 93 KTRs of which 75 were from Brazil. The mean time interval from transplantation to the onset of candidemia was 45.2 ± 61.5 months. 42% of all patients were on haemodialysis, 31.3% had an episode of sepsis and 39% underwent surgery within 30 days before fungemia. European patients were more likely to receive echinocandin (32 vs. 72%, p < .001). 22.7% of Brazilian patients did not receive any antifungal before death. All-cause mortality at 14 days was higher in Brazil (41.3 vs. 11.1%, p = .016). Candida colonisation (OR 6.91 [95% CI: 1.08-44.3], p = .042) and hypotension (OR 4.87 [95% CI: 1.62-14.66], p = .005) were associated with 14-day mortality. Echinocandin treatment had a protective effect (OR 0.19 [95% CI: 0.05-0.73], p = .015). Graft loss at 90 days occurred in 48% of patients (70.7 in Brazil vs. 22.2% in Europe, p < .01).

CONCLUSIONS

Candidemia in KTR is usually documented late after engraftment in patients requiring HD, surgical procedures and dysbiosis secondary to antibiotic use. Mortality was higher in Brazil. Echinocandin therapy was associated with improved survival.

Acquired Triazole Resistance Alters Pathogenicity-Associated Features in Candida auris in an Isolate-Dependent Manner

Fluconazole resistance is commonly encountered in Candida auris, and the yeast frequently displays resistance to other standard drugs, which severely limits the number of effective therapeutic agents against this emerging pathogen. In this study, we aimed to investigate the effect of acquired azole resistance on the viability, stress response, and virulence of this species. Fluconazole-, posaconazole-, and voriconazole- resistant strains were generated from two susceptible C. auris clinical isolates (0381, 0387) and compared under various conditions. Several evolved strains became pan-azole-resistant, as well as echinocandin-cross-resistant. While being pan-azole-resistant, the 0381-derived posaconazole-evolved strain colonized brain tissue more efficiently than any other strain, suggesting that fitness cost is not necessarily a consequence of resistance development in C. auris. All 0387-derived evolved strains carried a loss of function mutation (R160S) in BCY1, an inhibitor of the PKA pathway. Sequencing data also revealed that posaconazole treatment can result in ERG3 mutation in C. auris. Despite using the same mechanisms to generate the evolved strains, both genotype and phenotype analysis highlighted that the development of resistance was unique for each strain. Our data suggest that C. auris triazole resistance development is a highly complex process, initiated by several pleiotropic factors.

Advancing Vaccine Strategies against Candida Infections: Exploring New Frontiers

Candida albicans, along with several non-albicans Candida species, comprise a prominent fungal pathogen in humans, leading to candidiasis in various organs. The global impact of candidiasis in terms of disease burden, suffering, and fatalities is alarmingly high, making it a pressing global healthcare concern. Current treatment options rely on antifungal drugs such as azoles, polyenes, and echinocandins but are delimited due to the emergence of drug-resistant strains and associated adverse effects. The current review highlights the striking absence of a licensed antifungal vaccine for human use and the urgent need to shift our focus toward developing an anti-Candida vaccine. A number of factors affect the development of vaccines against fungal infections, including the host, intraspecies and interspecies antigenic variations, and hence, a lack of commercial interest. In addition, individuals with a high risk of fungal infection tend to be immunocompromised, so they are less likely to respond to inactivated or subunit whole organisms. Therefore, it is pertinent to discover newer and novel alternative strategies to develop safe and effective vaccines against fungal infections. This review article provides an overview of current vaccination strategies (live attenuated, whole-cell killed, subunit, conjugate, and oral vaccine), including their preclinical and clinical data on efficacy and safety. We also discuss the mechanisms of immune protection against candidiasis, including the role of innate and adaptive immunity and potential biomarkers of protection. Challenges, solutions, and future directions in vaccine development, namely, exploring novel adjuvants, harnessing the trained immunity, and utilizing immunoinformatics approaches for vaccine design and development, are also discussed. This review concludes with a summary of key findings, their implications for clinical practice and public health, and a call to action for continued investment in candidiasis vaccine research.

Overcoming clinical challenges in the management of invasive fungal infections in low- and middle-income countries (LMIC)

INTRODUCTION

The management of invasive fungal infections (IFIs) in low- and middle-income countries (LMIC) is a serious challenge due to limited epidemiology studies, sub-optimal laboratory facilities, gap in antifungal management training and resources. Limited studies highlighted distinctive epidemiology of IFIs in those countries, and difficulty in distinguishing from closely related infections. To overcome the gaps for appropriate management of IFIs, innovative approaches are required.

AREAS COVERED

Extensive literature search and discussion with experts have helped us to summarize the epidemiology, diagnostic and management difficulties in managing IFIs in LMIC, and recommend certain solutions to overcome the challenges.

EXPERT OPINION

The strategies to overcome the challenges in diagnosis may include local epidemiology study, training of healthcare workers, association of fungal infections with already existing budgeted national programs, development and incorporation of point-of-care test (POCT) for prompt diagnosis, simplifying clinical diagnostic criteria suitable for LMIC, judicious use of available expertise, and diagnostic stewardship. For management strategies judicious use of antifungal, partnering with industry for inexpensive antifungal agents, development of LMIC specific guidelines for cost-effective management of IFIs and fungal outbreaks, improvement of infection control practices, advocacy for implementation of WHO recommended antifungal use, and integration of IFIs with public health.

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

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

Neonatal invasive candidiasis in low- and middle-income countries: Data from the NeoOBS study

Neonatal invasive candidiasis (NIC) has significant morbidity and mortality. Reports have shown a different profile of those neonates affected with NIC and of fluconazole-resistant Candida spp. isolates in low- and middle-income countries (LMICs) compared to high-income countries (HICs). We describe the epidemiology, Candida spp. distribution, treatment, and outcomes of neonates with NIC from LMICs enrolled in a global, prospective, longitudinal, observational cohort study (NeoOBS) of hospitalized infants <60 days postnatal age with sepsis (August 2018-February 2021). A total of 127 neonates from 14 hospitals in 8 countries with Candida spp. isolated from blood culture were included. Median gestational age of affected neonates was 30 weeks (IQR: 28-34), and median birth weight was 1270 gr (interquartile range [IQR]: 990-1692). Only a minority had high-risk criteria, such as being born <28 weeks, 19% (24/127), or birth weight <1000 gr, 27% (34/127). The most common Candida species were C. albicans (n = 45, 35%), C. parapsilosis (n = 38, 30%), and Candida auris (n = 18, 14%). The majority of C. albicans isolates were fluconazole susceptible, whereas 59% of C. parapsilosis isolates were fluconazole-resistant. Amphotericin B was the most common antifungal used [74% (78/105)], followed by fluconazole [22% (23/105)]. Death by day 28 post-enrollment was 22% (28/127). To our knowledge, this is the largest multi-country cohort of NIC in LMICs. Most of the neonates would not have been considered at high risk for NIC in HICs. A substantial proportion of isolates was resistant to first choice fluconazole. Understanding the burden of NIC in LMIC is essential to guide future research and treatment guidelines.

Candida bloodstream infection among children hospitalised in three public-sector hospitals in the Metro West region of Cape Town, South Africa

BACKGROUND

Candida bloodstream infection (BSI) causes appreciable mortality in neonates and children. There are few studies describing the epidemiology of Candida BSI in children living in sub-Saharan Africa.

METHODS

A retrospective descriptive study was conducted at three public sector hospitals in Cape Town, South Africa. Demographic and clinical details, antifungal management and patient outcome data were obtained by medical record review. Candida species distribution and antifungal susceptibility testing results were obtained from the National Health Laboratory Service database.

RESULTS

Of the 97 Candida BSI episodes identified during a five-year period, 48/97 (49%) were Candida albicans (C. albicans), and 49/97 (51%) were non-C. albicans species. The overall incidence risk was 0.8 Candida BSI episodes per 1000 admissions at Red Cross War Memorial Children's Hospital. Of the 77/97 (79%) Candida BSI episodes with available clinical information, the median age (interquartile range) at the time of BSI was 7 (1-25) months, 36/77 (47%) were associated with moderate or severe underweight-for-age and vasopressor therapy was administered to 22/77 (29%) study participants. Most of the Candida BSI episodes were healthcare-associated infections, 63/77 (82%). Fluconazole resistance was documented among 17%, 0% and 0% of C. parapsilosis, C. tropicalis and C. albicans isolates, respectively. All Candida isolates tested were susceptible to amphotericin B and the echinocandins. The mortality rate within 30 days of Candida BSI diagnosis was 13/75 (17%). On multivariable analysis, factors associated with mortality within 30 days of Candida BSI diagnosis included vasopressor therapy requirement during Candida BSI, adjusted Odds ratio (aOR) 53 (95% confidence interval 2-1029); hepatic dysfunction, aOR 13 (95% CI 1-146); and concomitant bacterial BSI, aOR 10 (95% CI 2-60).

CONCLUSION

The study adds to the limited number of studies describing paediatric Candida BSI in sub-Saharan Africa. Non-C. Albicans BSI episodes occurred more frequently than C. albicans episodes, and vasopressor therapy requirement, hepatic dysfunction and concomitant bacterial BSI were associated with an increase in 30-day mortality.

Cost-utility analysis of caspofungin and fluconazole for primary treatment of invasive candidiasis and candidemia in Ethiopia

Background

Invasive candidiasis and/or candidemia (IC/C) is a common fungal infection leading to significant health and economic losses worldwide. Caspofungin was shown to be more effective than fluconazole in treating inpatients with IC/C. However, cost-effectiveness of caspofungin for treating IC/C in Ethiopia remains unknown. We aimed to assess the cost-utility of caspofungin compared to fluconazole-initiated therapies as primary treatment of IC/C in Ethiopia.

Methods

A Markov cohort model was developed to compare the cost-utility of caspofungin versus fluconazole antifungal agents as first-line treatment for adult inpatients with IC/C from the Ethiopian health system perspective. Treatment outcome was categorized as either a clinical success or failure, with clinical failure being switched to a different antifungal medication. Liposomal amphotericin B (L-AmB) was used as a rescue agent for patients who had failed caspofungin treatment, while caspofungin or L-AmB were used for patients who had failed fluconazole treatment. Primary outcomes were expected quality-adjusted life years (QALYs), costs (US$2021), and the incremental cost-utility ratio (ICUR). These QALYs and costs were discounted at 3% annually. Cost data was obtained from Addis Ababa hospitals while locally unavailable data were derived from the literature. Cost-effectiveness was assessed against the recommended threshold of 50% of Ethiopia’s gross domestic product/capita (i.e.,US$476). Deterministic and probabilistic sensitivity analyses were conducted to assess the robustness of the findings.

Results

In the base-case analysis, treatment of IC/C with caspofungin as first-line treatment resulted in better health outcomes (12.86 QALYs) but higher costs (US$7,714) compared to fluconazole-initiated treatment followed by caspofungin (12.30 QALYs; US$3,217) or L-AmB (10.92 QALYs; US$2,781) as second-line treatment. Caspofungin as primary treatment for IC/C was not cost-effective when compared to fluconazole-initiated therapies. Fluconazole-initiated treatment followed by caspofungin was cost-effective for the treatment of IC/C compared to fluconazole with L-AmB as second-line treatment, at US$316/QALY gained. Our findings were sensitive to medication costs, drug effectiveness, infection recurrence, and infection-related mortality rates. At a cost-effectiveness threshold of US$476/QALY, treating IC/C patient with fluconazole-initiated treatment followed by caspofungin was more likely to be cost-effective in 67.2% of simulations.

Conclusion

Our study showed that the use of caspofungin as primary treatment for IC/C in Ethiopia was not cost-effective when compared with fluconazole-initiated treatment alternatives. The findings supported the use of fluconazole-initiated therapy with caspofungin as a second-line treatment for patients with IC/C in Ethiopia.

Deciphering Colonies of Phenotypic Switching-Derived Morphotypes of the Pathogenic Yeast Candida tropicalis

BACKGROUND

Phenotypic switching generates fungal colonies with altered morphology and allows pathogens to adapt to changing environments.

OBJECTIVE

This study investigated the structure and genetic factors of switched morphotypes colonies in Candida tropicalis.

METHODS

Morphotypes of C. tropicalis comprised the clinical strain 49.07 that exhibited smooth colony phenotype and switched (crepe and rough) morphotypes that showed colonies with marked structural variations, including wrinkled surface, depressions areas, and irregular edges (structured morphology). The morphotypes were analyzed for the presence and distribution of the extracellular matrix (ECM) at the ultrastructural level-SEM. The composition of the ECM and the percentage of hyphae in colonies were evaluated. The expression of EFG1 (Enhanced filamentous growth protein 1), WOR1 (White-opaque regulator 1), and BCR1 (Biofilm and cell wall regulator 1) in the morphotypes was measured by RT-qPCR.

RESULTS

Colonies of the switched variants exhibited distinct arrangements of ECM compared to the smooth phenotype (clinical strain). In addition, rough variant colonies showed higher amounts of total carbohydrates and proteins in ECM (p < 0.05). Switched (crepe and rough) colonies exhibited a higher percentage of hyphae throughout their development (p < 0.05). The mRNA expression levels of EFG1, WOR1, and BCR1 in the rough morphotype were significantly higher than they were in the smooth morphotype. In addition, there was a positive correlation between the expression of these genes and filamentation (hyphae formation) of the rough morphotype (r² > 0.9472, p < 0.05).

CONCLUSION

Structural variations in switched morphotypes colonies of C. tropicalis seem to be associated with increased hyphae growth and the amount and distribution of ECM. Switched colonies have distinct expressions of the EFG1, WOR1, and BCR1 master regulators genes.

A quality improvement initiative to improve the appropriateness of candidemia management by the implementation of a comprehensive candidemia care bundle at a tertiary care hospital in South India: Results of a quasi-experimental study

Management of candidemia in developing countries like India encounters laxity in appropriate clinical management and challenges in terms of healthcare capacity, despite its association with high morbidity and mortality. Our study aims to evaluate the impact of a comprehensive candidemia care bundle implementation on appropriateness of therapy and major clinical outcomes.The single-center, quasi-experimental study conducted at a south Indian tertiary care center included adult patients diagnosed with candidemia. Following a retrospective review of candidemia patients of the pre-implementation period (January 2013-December 2015), the hospital antifungal stewardship team instituted a clinical pharmacist driven comprehensive candidemia care bundle for candidemia patients during the post-implementation period (October 2017-2019) and its impact on appropriateness of antifungal prescriptions and inpatient mortality was evaluated.The study included 175 patients with candidemia, comprising of 103 patients in the pre-implementation period and 72 patients in the post-implementation period. Appropriateness of antifungal prescriptions rose to 65% during post-implementation period from 30% observed in pre-implementation phase (P = .0005). The inhospital mortality rate reduced from 40% in the pre-implementation phase to 36% in the post-implementation phase, recording a 10% reduction over 2 years post-implementation (P = .26). No significant difference was observed in terms length of stay (P = .17).Our study demonstrates the successful implementation of an antifungal stewardship led comprehensive care bundle in a low middle income countries setting. The results of our study will have profound implications in improving the appropriateness of management of candidemia and feasibility of scaling up to wider settings could be explored.

A Brazilian Inter-Hospital Candidemia Outbreak Caused by Fluconazole-Resistant Candida parapsilosis in the COVID-19 Era

Horizontal transmission of fluconazole-resistant Candida parapsilosis (FRCP) through healthcare workers’ hands has contributed to the occurrence of candidemia outbreaks worldwide. Since the first COVID-19 case in Brazil was detected in early 2020, hospitals have reinforced hand hygiene and disinfection practices to minimize SARS-CoV-2 contamination. However, a Brazilian cardiology center, which shares ICU patients with a cancer center under a FRCP outbreak since 2019, reported an increased FRCP candidemia incidence in May 2020. Therefore, the purpose of this study was to investigate an inter-hospital candidemia outbreak caused by FRCP isolates during the first year of the COVID-19 pandemic in Brazil. C. parapsilosis bloodstream isolates obtained from the cancer (n = 35) and cardiology (n = 30) centers in 2020 were submitted to microsatellite genotyping and fluconazole susceptibility testing. The ERG11 gene of all isolates from the cardiology center was sequenced and compared to the corresponding sequences of the FRCP genotype responsible for the cancer center outbreak in 2019. Unprecedentedly, most of the FRCP isolates from the cardiology center presented the same genetic profile and Erg11-Y132F mutation detected in the strain that has been causing the persistent outbreak in the cancer center, highlighting the uninterrupted horizontal transmission of clonal isolates in our hospitals during the COVID-19 pandemic.

Neonatal invasive candidiasis: updates on clinical management and prevention

Neonatal invasive candidiasis is an important cause of morbidity and mortality in preterm infants. The incidence of invasive candidiasis in this population has been declining in high-income settings, largely due to preventive measures, although there are still considerable variations in incidence between health-care centres. Surveillance data and large, multicentre studies in lower-income settings are not available, although preventive measures in these settings have been shown to decrease the incidence of neonatal invasive candidiasis. Understanding risk factors and pathogenesis are key to the prevention of invasive candidiasis. The difficulty of a definitive diagnosis of invasive candidiasis and the high risk for death or substantial neurodevelopmental impairment, even with appropriate treatment, further increase the need for effective preventive measures. In this Review, we examine the pathogenesis, clinical presentation, and diagnosis of invasive candidiasis. We highlight commonly used and emerging preventive and prophylactic measures, including standardised central line care, antibiotic stewardship, antifungal prophylaxis, and probiotics. Finally, we provide updates on empirical treatment, clinical management in confirmed cases of invasive candidiasis, and antifungal pharmacotherapy.

Fungal Infections in COVID-19 Intensive Care Patients

Opportunistic fungal infections increase morbidity and mortality in COVID-19 patients monitored in intensive care units (ICU). As patients' hospitalization days in the ICU and intubation period increase, opportunistic infections also increase, which prolongs hospital stay days and elevates costs. The study aimed to describe the profile of fungal infections and identify the risk factors associated with mortality in COVID-19 intensive care patients. The records of 627 patients hospitalized in ICU with the diagnosis of COVID-19 were investigated from electronic health records and hospitalization files. The demographic characteristics (age, gender), the number of ICU hospitalization days and mortality rates, APACHE II scores, accompanying diseases, antibiotic-steroid treatments taken during hospitalization, and microbiological results (blood, urine, tracheal aspirate samples) of the patients were recorded. Opportunistic fungal infection was detected in 32 patients (5.10%) of 627 patients monitored in ICU with a COVID-19 diagnosis. The average APACHE II score of the patients was 28 ± 6. While 25 of the patients (78.12%) died, seven (21.87%) were discharged from the ICU. Candida parapsilosis (43.7%) was the opportunistic fungal agent isolated from most blood samples taken from COVID-19 positive patients. The mortality rate of COVID-19 positive patients with candidemia was 80%. While two out of the three patients (66.6%) for whom fungi were grown from their tracheal aspirate died, one patient (33.3%) was transferred to the ward. Opportunistic fungal infections increase the mortality rate of COVID-19-positive patients. In addition to the risk factors that we cannot change, invasive procedures should be avoided, constant blood sugar regulation should be applied, and unnecessary antibiotics use should be avoided.

Spectrum and Antifungal Resistance of Candidemia in Neonates With Early- and Late-Onset Sepsis in Pakistan

BACKGROUND

Neonatal candidemia leads to high morbidity and mortality in developing countries. We studied the trends, spectrum and antifungal resistance in neonatal candidemia isolates from the year 2014 to 2019.

METHODS

This was a cross-sectional study conducted at the Aga Khan University, Pakistan. Neonates with positive blood cultures with Candida species were retrospectively identified from the laboratory database (2014-2018) and prospectively in 2019 where clinical information was also collected as part of routine laboratory reporting.

RESULTS

We identified 669 neonates with Candida species in blood cultures. Three hundred forty-six neonates had early-onset disease (EOD age ≤7 days) and 323 had late-onset disease (LOD age >7 days). Non-albicans Candida species (86.7%) were predominant versus C. albicans (13.3%; P-value 0.024) with Candida tropicalis being most common in both EOD and LOD. Candida pelliculosa and Candida guilliermondii were associated with EOD and C. albicans with LOD. Isolation of fluconazole nonsusceptible non-albicans Candida species was significantly higher in early-onset (5.9%) versus late-onset (2%) neonatal candidemia (P-value 0.005; crude odds ratio [COR] 2.73, 95% CI: 1.34-5.53). LOD in neonates was more likely associated with the use of vancomycin (COR 3.89, 95% CI: 1.39-10.89). EOD was more likely seen in patients with vaginal delivery (COR 4.16, 95% CI: 1.42-12.23) and in neonates with respiratory distress leading to intensive care unit admission (COR 3.31, 95% CI: 1.05-10.42).

CONCLUSIONS

Non-albicans Candida species were increasingly isolated from neonates with candidemia during recent years from Pakistan. Amphotericin remains first-line option for neonatal candidemia in our setting as fluconazole nonsusceptible Candida species are commonly isolated.

Epidemiology of Culture-confirmed Candidemia Among Hospitalized Children in South Africa, 2012-2017

BACKGROUND

We aimed to describe the epidemiology of candidemia among children in South Africa.

METHODS

We conducted laboratory-based surveillance among neonates (≤28 days), infants (29 days to <1 year), children (1-11 years) and adolescents (12-17 years) with Candida species cultured from blood during 2012-2017. Identification and antifungal susceptibility of viable isolates were performed at a reference laboratory. We used multivariable logistic regression to determine the association between Candida parapsilosis candidemia and 30-day mortality among neonates.

RESULTS

Of 2996 cases, neonates accounted for 49% (n = 1478), infants for 27% (n = 806), children for 20% (n = 589) and adolescents for 4% (n = 123). The incidence risk at tertiary public sector hospitals was 5.3 cases per 1000 pediatric admissions (range 0.39-119.1). Among 2943 cases with single-species infections, C. parapsilosis (42%) and Candida albicans (36%) were most common. Candida auris was among the 5 common species with an overall prevalence of 3% (n = 47). Fluconazole resistance was more common among C. parapsilosis (55% [724/1324]) versus other species (19% [334/1737]) (P < 0.001). Of those with known treatment (n = 1666), 35% received amphotericin B deoxycholate alone, 32% fluconazole alone and 30% amphotericin B deoxycholate with fluconazole. The overall 30-day in-hospital mortality was 38% (n = 586) and was highest among neonates (43% [323/752]) and adolescents (43% [28/65]). Compared with infection with other species, C. parapsilosis infection was associated with a reduced mortality among neonates (adjusted odds ratio 0.41, 95% confidence interval: 0.22-0.75, P = 0.004).

CONCLUSIONS

Candidemia in this setting mainly affected neonates and infants and was characterized by fluconazole-resistant C. parapsilosis with no increased risk of death.

8-hydroxyquinoline-5-(N-4-chlorophenyl) sulfonamide and fluconazole combination as a preventive strategy for Candida biofilm in haemodialysis devices

Introduction. The presence of Candida biofilms in medical devices is a concerning and important clinical issue for haemodialysis patients who require constant use of prosthetic fistulae and catheters.Hypothesis/Gap Statement. This prolonged use increases the risk of candidaemia due to biofilm formation. PH151 and clioquinol are 8-hydroxyquinoline derivatives that have been studied by our group and showed interesting anti-Candida activity.Aim. This study evaluated the biofilm formation capacity of Candida species on polytetrafluoroethylene (PTFE) and polyurethane (PUR) and investigated the synergistic effects between the compounds PH151 and clioquinol and fluconazole, amphotericin B and caspofungin against biofilm cells removed from those materials. Further, the synergistic combination was evaluated in terms of preventing biofilm formation on PTFE and PUR discs.Methodology. Susceptibility testing was performed for planktonic and biofilm cells using the broth microdilution method. The checkerboard method and the time-kill assay were used to evaluate the interactions between antifungal agents. Antibiofilm activity on PTFE and PUR materials was assessed to quantify the prevention of biofilm formation.Results. Candida albicans, Candida glabrata and Candida tropicalis showed ability to form biofilms on both materials. By contrast, Candida parapsilosis did not demonstrate this ability. Synergistic interaction was observed when PH151 was combined with fluconazole in 77.8 % of isolates and this treatment was shown to be concentration- and time-dependent. On the other hand, indifferent interactions were predominantly observed with the other combinations. A reduction in biofilm formation on PUR material of more than 50 % was observed when using PH151 combined with fluconazole.Conclusion. PH151 demonstrated potential as a local treatment for use in a combination therapy approach against Candida biofilm formation on haemodialysis devices.

Risk Factors for Mortality in Colombian Patients with Candidemia

The aim of the study was to describe the microbiology and susceptibility profile of candidemia and to identify the risk factors associated with mortality in Colombia. A cohort of patients was followed for 30 days during 2008 to 2010. Microbiological identification and susceptibility assessments were performed in a reference centre. Demographic, clinical and treatment variables were evaluated for their associations with mortality. A parametric survival regression analysis was used to identify the risk factors associated with mortality. A total of 109 patients with candidemia in four hospitals in Colombia were identified, with a median age of 30 years old. C. parapsilosis was the most frequently identified microorganism (38.5%); the susceptibility of all isolates was high to fluconazole and anidulafungin, except for C. glabrata isolates. The overall mortality was 35.7%, and the risk factors associated with mortality included lack of antifungal treatment (HR 5.5, 95% CI 3.6–11.4), cancer (HR 3.9, 95% CI 2.3–8.0), diabetes (HR 2.5, 95% CI 1.03–6.4), and age (HR 1.13 per every 10 years, 95% CI 1.02–1.24). Catheter removal was associated with a low mortality rate (HR 0.06, 95% CI 0.00–0.49). Prompt antifungal treatment, better glycemic control and catheter removal should be prioritized in the management of candidemia.

Evaluating the measures taken to contain a Candida auris outbreak in a tertiary care hospital in South India: an outbreak investigational study

BACKGROUND

Candida auris infections are an emerging global threat with poor clinical outcome, high mortality rate, high transmission rate and outbreak potential. The objective of this work is to describe a multidisciplinary approach towards the investigation and containment of a Candida auris outbreak and the preventive measures adopted in a resource limited setting.

METHODS

This outbreak investigational study was conducted at a 1300-bedded tertiary care academic hospital in South India. The study included 15 adult inpatients with laboratory confirmed Candida auris isolates. The outbreak cluster was identified in adult patients admitted from September 2017 to 2019. The system response consisted of a critical alert system for laboratory confirmed Candida auris infection and multidisciplinary 'Candida auris care team' for patient management. The team implemented stringent Infection Prevention and Control (IPC) measures including patient cohorting, standardized therapy and decolonization, staff training, prospective surveillance and introduction of Candida auris specific care bundle.

RESULTS

Two outbreak clusters were identified; first cluster occurring between October and November 2017 and the second cluster in May 2018. The cohorts consisted of 7 and 8 Candida auris positive patients in the first and second waves of the outbreak respectively with a total survival rate of 93% (14/15). Deployment of containment measures led to gradual decline in the incidence of adult Candida auris positive cases and prevented further cluster formation.

CONCLUSIONS

The sustained implementation of guideline and evidence-based IPC measures and training of healthcare workers for improving awareness on systematically following standardized protocols of Candida auris related IPC practices successfully contained Candida auris outbreaks at our hospital. This demonstrates the feasibility of establishing a multidisciplinary model and bundling of practices for preventing Candida auris outbreaks in a Low- and Middle-income country.

Timing for Step-Down Therapy of Candidemia in Non-Neutropenic Patients: An International Multi-Center Study

Background

Candida bloodstream infection (BSI) remains one of the leading causes of BSI in critically ill and immunosuppressed cancer patients. In light of the changing epidemiology and rising resistant species, duration of treatment and appropriate timing of stepdown therapy from intravenous (IV) to oral antifungal agents are crucial for utmost disease control and overall survival.

Method

We performed a multicenter retrospective study, with 119 non-neutropenic patients enrolled from four different medical institutions in Brazil, Lebanon, Spain and the United States, to assess the duration of IV therapy and appropriate time to step-down to oral therapy in adult patients, 14 years of age and older, with documented candidemia. The analysis was done using the statistical program R and SAS v9.4. Descriptive statistics are presented as frequencies and tables and the Fisher exact test was used to test the association between the categorical variables: organism, cancer, country, antifungal drug and duration of therapy, and time of step-down.

Results

Candida albicans contributed to 45% of bloodstream infection versus 55% of infection caused by Candida non-albicans. The three most common Candida non-albicans are: Candida glabrata 24%, Candida parapsilosis 13% and Candida tropicalis 8%. Most (57%) of the patients were admitted to ICU, whereas 52% had underlying malignancy. Multivariate analysis showed that a stay at ICU or an underlying cancer requiring chemotherapy were independently associated with failure and death (p <0.001). The average total duration of therapy was 14 days in all patients and 16 days in those who responded and survived. Forty-five patients were stepped down to either fluconazole and/or voriconazole in association with clinical and microbiologic resolution of the candidemia. The average (and median) day of step-down was 5 days. Patients who had a stepdown had more favorable outcomes (78% survival) as compared to those with no stepdown (56% survival) (P = 0.022). However, the 20 patients who received 1–4 days of first IV treatment before a stepdown to oral azoles had a comparable outcome (20% mortality) to the 25 patients who received >5 days of treatment (24% mortality - p = 0.75).

Conclusion

Our data support the IDSA guidelines in that the total duration of treatment for candidemia should be at least 14 days after a negative blood culture. However, in non-neutropenic cancer patients with candidemia, a step-down to oral azole therapy can safely take place early (within 4 days of initiating IV therapy) as long as the patient had clinical and microbiologic resolution of the bloodstream infections.

Antifungal and Antibiofilm Activities of B-Type Oligomeric Procyanidins From Commiphora leptophloeos Used Alone or in Combination With Fluconazole Against Candida spp

Commiphora leptophloeos (Burseraceae) is a medicinal plant native to Brazil which is popularly used for treating oral and vaginal infections. There has been no scientific evidence pointing to its efficacy in the treatment of these infections. Thus, this study sought to investigate the cytotoxic, antifungal, and antibiofilm activity of C. leptophloeos against Candida spp. and to isolate, identify, and quantify the content of B-type oligomeric procyanidins (BDP) in the extract of C. leptophloeos stem bark. The extract and the n-butanol fraction were obtained by maceration and liquid-liquid partition, respectively. Phytochemical analysis performed by HPLC-PDA/ELSD and FIA-ESI-IT-MS/MS allowed the identification and quantification of BDP in the samples. The application of centrifugal partition chromatography helped isolate BDP, which was identified by ¹H NMR and MS analyses. Candida spp. reference strains and clinical isolates (including fluconazole-resistant strains) derived from the blood cultures of candidemic patients and the vaginal secretion of patients with vulvovaginal candidiasis were used for evaluating the antifungal and antibiofilm effects. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were determined by the microdilution technique, and biofilm inhibition was evaluated through crystal violet and XTT assays. The combined action of BDP with fluconazole was determined by the checkerboard method. The extract, the n-butanol fraction, and the BDP exhibited antifungal activity with MIC values ranging from 312.5 to 2500 μg/mL and were found to significantly reduce the biofilm formed in all the Candida strains investigated. BDP showed a fungicidal potential against strains of Candida spp. (especially against fluconazole-resistant strains), with MIC and MFC values ranging from 156.2 to 2500 μg/mL. In addition, the combined application of BDP and fluconazole produced synergistic antifungal effects against resistant Candida spp. (FICI = 0.31-1.5). The cytotoxic properties of the samples evaluated in human erythrocytes through hemolytic test did not show hemolytic activity under active concentrations. The findings of the study show that C. leptophloeos has antifungal and antibiofilm potential but does not cause toxicity in human erythrocytes. Finally, BDP, which was isolated for the first time in C. leptophloeos, was found to exhibit antifungal effect against Candida spp. either when applied alone or in combination with fluconazole.

Verapamil inhibits efflux pumps in Candida albicans, exhibits synergism with fluconazole, and increases survival of Galleria mellonella

The emergence of resistance requires alternative methods to treat Candida albicans infections. We evaluated efficacy of the efflux pump inhibitor (EPI) verapamil (VER) with fluconazole (FLC) against FLC-resistant (CaR) and -susceptible C. albicans (CaS). The susceptibility of both strains to VER and FLC was determined, as well as the synergism of VER with FLC. Experiments were performed in vitro for planktonic cultures and biofilms and in vivo using Galleria mellonella. Larval survival and fungal recovery were evaluated after treatment with VER and FLC. Data were analyzed by analysis of variance and Kaplan-Meier tests. The combination of VER with FLC at sub-lethal concentrations reduced fungal growth. VER inhibited the efflux of rhodamine 123 and showed synergism with FLC against CaR. For biofilms, FLC and VER alone reduced fungal viability. The combination of VER with FLC at sub-lethal concentrations also reduced biofilm viability. In the in vivo assays, VER and FLC used alone or in combination increased the survival of larvae infected with CaR. Reduction of fungal recovery was observed only for larvae infected with CaR and treated with VER with FLC. VER reverted the FLC-resistance of C. albicans. Based on the results obtained, VER reverted the FLC-resistance of C. albicans and showed synergism with FLC against CaR. VER also increased the survival of G. mellonella infected with CaR and reduced the fungal recovery.

European confederation of medical mycology quality of clinical candidaemia management score: A review of the points based best practice recommendations

Candidaemia is associated with high mortality. In the last few years, several guidelines have been published on the management of Candida bloodstream infection. However, adherence to the practice guidelines has been suboptimal. In order to facilitate and objectively measure the adherence to good practice recommendations, a scoring criterion was published by the European Confederation of Medical Mycology (ECMM). The ECMM Quality (EQUAL) of Clinical Candidaemia Management is an audit tool that comprises of 10 quality indicators. Each quality indicator is allotted between 1 and 3 points. The maximum achievable score is 22 or 19 in patients with or without a central venous catheter, respectively. This paper reviews each of the 10 quality indicators and provides the context for improving quality within the individual domains. The review also suggests areas that are in need of further clarity or areas which merit attention in the future updates of the EQUAL scoring system so that clinicians are able to derive maximum benefit from the audit tool. The EQUAL scoring tool is an important milestone in the quality improvement aspect of the management of candidaemia and contributes to the various components of clinical governance in the management of Candida infection of the bloodstream.

Quantification of Factor H Mediated Self vs. Non-self Discrimination by Mathematical Modeling

The complement system is part of the innate immune system and plays an important role in the host defense against infectious pathogens. One of the main effects is the opsonization of foreign invaders and subsequent uptake by phagocytosis. Due to the continuous default basal level of active complement molecules, a tight regulation is required to protect the body's own cells (self cells) from opsonization and from complement damage. A major complement regulator is Factor H, which is recruited from the fluid phase and attaches to cell surfaces where it effectively controls complement activation. Besides self cells, pathogens also have the ability to bind Factor H; they can thus escape opsonization and phagocytosis causing severe infections. In order to advance our understanding of the opsonization process at a quantitative level, we developed a mathematical model for the dynamics of the complement system-termed DynaCoSys model-that is based on ordinary differential equations for cell surface-bound molecules and on partial differential equations for concentration profiles of the fluid phase molecules in the environment of cells. This hybrid differential equation approach allows to model the complement cascade focusing on the role of active C3b in the fluid phase and on the cell surface as well as on its inactivation on the cell surface. The DynaCoSys model enables us to quantitatively predict the conditions under which Factor H mediated complement evasion occurs. Furthermore, investigating the quantitative impact of model parameters by a sensitivity analysis, we identify the driving processes of complement activation and regulation in both the self and non-self regime. The two regimes are defined by a critical Factor H concentration on the cell surface and we use the model to investigate the differential impact of complement model parameters on this threshold value. The dynamic modeling on the surface of pathogens are further relevant to understand pathophysiological situations where Factor H mutants and defective Factor H binding to target surfaces results in pathophysiology such as renal and retinal disease. In the future, this DynaCoSys model will be extended to also enable evaluating treatment strategies of complement-related diseases.

Preterm birth and sustained inflammation: consequences for the neonate

Almost half of all preterm births are caused or triggered by an inflammatory process at the feto-maternal interface resulting in preterm labor or rupture of membranes with or without chorioamnionitis (“first inflammatory hit”). Preterm babies have highly vulnerable body surfaces and immature organ systems. They are postnatally confronted with a drastically altered antigen exposure including hospital-specific microbes, artificial devices, drugs, nutritional antigens, and hypoxia or hyperoxia (“second inflammatory hit”). This is of particular importance to extremely preterm infants born before 28 weeks, as they have not experienced important “third-trimester” adaptation processes to tolerate maternal and self-antigens. Instead of a balanced adaptation to extrauterine life, the delicate co-regulation between immune defense mechanisms and immunosuppression (tolerance) to allow microbiome establishment is therefore often disturbed. Hence, preterm infants are predisposed to sepsis but also to several injurious conditions that can contribute to the onset or perpetuation of sustained inflammation (SI). This is a continuing challenge to clinicians involved in the care of preterm infants, as SI is regarded as a crucial mediator for mortality and the development of morbidities in preterm infants. This review will outline the (i) role of inflammation for short-term consequences of preterm birth and (ii) the effect of SI on organ development and long-term outcome.

Assessment of antifungal resistance and associated molecular mechanism in Candida albicans isolates from different cohorts of patients in North Indian state of Haryana

The present study examines the trend in distribution of Candida species and their antifungal resistance patterns in hospitals across Haryana, a North Indian state with poorly addressed epidemiology of fungal infections. In our collection of 228 Candida isolates, Candida albicans dominated in both high vaginal swab (HVS) and urine samples while Candida glabrata and Candida tropicalis were the second-highest non-albicans Candida species (NAC), respectively. Of note, in blood samples, C. tropicalis and C. albicans were present in equal numbers. All 228 isolates were subjected to antifungal susceptibility tests, whereby 51% of C. albicans recovered from HVS samples displayed fluconazole resistance. To understand its mechanistic basis, expression profiling of efflux pump genes CDR1, CDR2, MDR1 and azole drug target, ERG11 was performed in 20 randomly selected resistant isolates, wherein many isolates elicited higher expression. Further, ERG11 gene sequencing suggested that most of the isolates harbored mutations, which are not reported with azole resistance. However, one isolate, RPCA9 (MIC 64 μg/mL) harbored triple mutation (Y132C, F145L, A114V), wherein Y132 and F145 sites were previously implicated in azole resistance. Interestingly, one isolate, (RPCA61) having MIC > 128 μg/mL harbored a novel mutation, G129R. Of note, HVS isolates RPCA 21, RPCA 22, and RPCA 44 (MICs 64 to > 128 μg/mL) did not show any change in alteration in ERG11 or overexpression of efflux pump genes. Together, this study presents a first report of Candida infections in selected hospitals of Haryana State.

Mechanisms of Pathogenic Candida Species to Evade the Host Complement Attack

Candida species are common colonizers of the human skin, vagina, and the gut. As human commensals, Candida species do not cause any notable damage in healthy individuals; however, in certain conditions they can initiate a wide range of diseases such as chronic disseminated candidiasis, endocarditis, vaginitis, meningitis, and endophthalmitis. The incidence of Candida caused infections has increased worldwide, with mortality rates exceeding 70% in certain patient populations. C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, and C. krusei are responsible for more than 90% of Candida-related infections. Interestingly, the host immune response against these closely related fungi varies. As part of the innate immune system, complement proteins play a crucial role in host defense, protecting the host by lysing pathogens or by increasing their phagocytosis by phagocytes through opsonization. This review summarizes interactions of host complement proteins with pathogenic Candida species, including C. albicans and non-albicans Candida species such as C. parapsilosis. We will also highlight the various ways of complement activation, describe the antifungal effects of complement cascades and explore the mechanisms adopted by members of pathogenic Candida species for evading complement attack.

Candida bloodstream infection in patients with systemic autoimmune diseases

OBJECTIVES

To describe the epidemiological, clinical and microbiological characteristics and mortality of patients with Candida bloodstream infection and systemic autoimmune diseases.

METHODS

We performed a retrospective multicenter study of candidemia in adults with systemic autoimmune diseases between 2010 and 2016.

RESULTS

Among 1040 patients with candidemia, 36 (3.5%) had a systemic autoimmune disease. The most common systemic autoimmune disease was rheumatoid arthritis (27.8%). The most common species was Candida albicans (66.7%). Twenty-two (61.1%) patients received a corticosteroid therapy and nine (25%) received an immunosuppressive therapy at the time of candidemia. The mortality rate was 27.8%.

CONCLUSIONS

Systemic autoimmune diseases are not common in patients with candidemia. The unadjusted mortality rate was comparable to other candidemia studies in the general population.

Prolonged Outbreak of Candida krusei Candidemia in Paediatric Ward of Tertiary Care Hospital

Background

A sudden rise of Candida krusei candidemia cases was noticed in our hospital within 1 year with maximum cases from paediatric unit. The present study reports the results of epidemiological investigation of possible outbreak of candidemia by C. krusei in paediatric unit at our tertiary care centre.

Methods

Clinical characteristics and risk factors associated with C. krusei candidemia were evaluated. Yeast identification and antifungal susceptibility testing was performed according to standard protocol. To find the potential source of C. krusei in hospital environment and hand colonization, swabs were collected from different fomites (n = 40) and hand washings from 24 health care workers (HCW), respectively. Infection control and prevention practices were intensified following the recognition of outbreak. Genetic typing was done by fluorescent amplified fragment length polymorphism (FAFLP) technique. Case–control comparison was performed with C. tropicalis and C. pelliculosa cases.

Results

Candida krusei fungaemia significantly affected paediatric group (82/186, 44%) as compared to adults (14/130, 10.8%; p < 0.001). Among paediatric group, maximum isolation was reported from neonatal unit of paediatric emergency (NUPE). C. krusei was isolated from hands of one HCW and washbasin in NUPE. FAFLP revealed clonality between blood and environmental isolates indicating cross-transmission of C. krusei. Gastrointestinal disease (p = 0.018), previous antibiotics (p = 0.021) especially to carbapenems (p = 0.039), was significant among C. krusei candidemia cases compared to C. pelliculosa cases.

Conclusion

We report the largest outbreak of C. krusei candidemia in paediatric unit within 1 year with isolation of related strains from environment and hands of HCW. Routine screening of hand hygiene practices revealed non-compliance to standard practices leading to the increase in C. krusei candidemia cases.

Candidaemia in a tertiary care centre of developing country: Monitoring possible change in spectrum of agents and antifungal susceptibility

Purpose

Candidaemia is a major cause of morbidity and mortality of hospitalised patients, especially in developing countries. This study was conducted to monitor any change in species distribution and antifungal susceptibility pattern of Candida species causing candidaemia over the last 20 years.

Materials and Methods

The candidaemia cases reported during January 1999 and December 2018 at our centre were reviewed. The yeasts were identified by phenotypic characters (during 1999-2014) and matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF MS) (during 2014-2018). Antifungal susceptibility testing (AFST) was performed in accordance with the Clinical and Laboratory Standards Institute guidelines.

Results

A total of 602,963 blood samples from patients with suspected sepsis were processed. Candidaemia was diagnosed in 7927 (1.31%) cases. The frequency of cases rose significantly (P = 0.000) in the last quarter of the study. Candida tropicalis (40.1%) was the most common species, followed by Candida albicans (15.2%), Wickerhamomyces anomalus (13.1%), Candida krusei (6.6%), Candida parapsilosis (4.7%) and others. Rare species such as Candida auris, Candida lambica, Candida orthopsilosis, Candida vishwanathii were identified after the introduction of MALDI-TOF. The minimum inhibitory concentrations of amphotericin B rose significantly from the first to last quarter (0.5%-4.9%). Fluconazole resistance was fairly constant at 7.4%-8.8%.

Conclusion

Local epidemiology of candidaemia at our centre was distinct regarding prevalence and change of spectrum of species. The identification of rare species was possible after the introduction of MALDI-TOF. With the emergence of multidrug-resistant C. auris and resistance in other species, routine AFST has become imperative.

A Paradigm Shift in the Development of Anti-Candida Drugs

BACKGROUND

The considerable increase in the incidence of Candida infection in recent times has prompted the use of numerous antifungal agents, which has resulted in the development of resistance towards various antifungal agents. With rising Candida infections, the need for design and development of novel antifungal agents is in great demand. However, new therapeutic approaches are very essential in preventing the mortality rate and improving the patient outcome in those suffering from Candida infections.

OBJECTIVE

The present review objective is to describe the burden, types of Candidiasis, mechanism of action of antifungal agents and its resistance and the current novel approaches used to combat candidiasis.

METHODS

We have collected and analyzed 135 different peer-reviewed literature studies pertinent to candidiasis. In this review, we have compiled the major findings from these studies.

RESULTS AND CONCLUSION

The review describes the concerns related to candidiasis, its current treatment strategy, resistance mechanisms and imminent ways to tackle the problem. The review explored that natural plant extracts and essential oils could act as sources of newer therapeutic agents, however, the focus was on novel strategies, such as combinational therapy, new antibodies, utilization of photodynamic therapy and adaptive transfer primed immune cells with emphasis on the development of effective vaccination.

To study the profile of Candida isolates and antifungal susceptibility pattern of neonatal sepsis in a tertiary care hospital of North India

AIMS AND OBJECTIVE

To study the profile of Candida infection and antifungal susceptibility (AFS) pattern in neonatal sepsis.

MATERIALS AND METHODS

In this prospective observational study, 850 blood samples were collected and processed from neonates who were suspected clinically to have sepsis. The blood culture that showed growth of Candida was further processed for species identification. Antifungal susceptibility was done as per the National Committee for Clinical Laboratory Standards (NCCLS)/Clinical Laboratory Standards Institute (CLSI) M44-A-2 guidelines by disc diffusion method and automated vitek-2 compact system. Candidemia was diagnosed by isolation of Candida species from at least one positive blood culture containing pure growth of Candida species with supportive clinical features.

RESULTS

Candida species were isolated in 32 specimens of the total 322 culture-positive cases. The most common isolate was Candida tropicalis (14/32; 43.75%) followed by Candida albicans (7/32; 21.87%) and Candida glabrata (6/32; 18.75%). The three most common neonatal risk factors for candidemia were low birth weight, prolonged use of intravenous antibiotics and presence of central venous line. Non-albicans Candida (NAC) showed good sensitivity to fluconazole as compared to Candida albicans. The fluconazole sensitivity of Candida tropicalis, Candida glabrata, and Candida parapsilosis was 93, 67, and 100%, respectively, whereas it was 57% in Candida albicans. The sensitivity to amphotericin B was 95% among all Candida isolates. All NAC were sensitive to amphotericin B, while only 72% Candida albicans were sensitive to amphotericin B.

CONCLUSIONS

The incidence of neonatal sepsis secondary to NAC is increasing and has replaced Candida albicans as a major cause of neonatal fungal sepsis. Low birth weight is the most important risk factor for Candida sepsis. The resistance of Candida albicans is increasing for both fluconazole and amphotericin B when compared to NAC. Increasing antifungal resistance warrants its judicious use both for prophylaxis and treatment.

Study of Antifungal Susceptibility, Virulence Genes and Biofilm Formation in Candida albicans

Background:

Candida albicans has emerged as an important nosocomial pathogen. The morbidity and mortality associated with this pathogen are related to the presence of virulence genes and antifungal resistance. The objective of the present study was to investigate the prevalence of antifungal resistance, biofilm formation and some virulence genes such as ALS1, PLB1, INT1, SAP1 and HWP1, among clinical isolates of Candida albicans recovered from immunocompromised patients.

Methods:

The study included one hundred C. albicans isolates identified phenotypically and by a molecular technique using Polymerase Chain Reaction (PCR). The identified C. albicans was further subjected to antifungal study by the microdilution method, biofilm study and molecular study for virulence genes by PCR.

Results:

The resistance to antifungal drugs, fluconazole, caspofungin and itraconazole was 8% for each of them and for amphotericin B, it was 9%. The prevalence of the studied virulence genes was HWP1 77%, INT1 72%, ALS1 65%, SAP1 65% and PLB1 52%. The biofilm capacity was identified by the microplate method in 58% of C. albicans. The OD was intense in 20 isolates, moderate in 21 isolates and mild in 17 isolates. There was a statistically significant increase in the prevalence of the studied virulence genes INT1, ALS1, HWP1, SAP1 and PLB1 among biofilm forming C. albicans as compared to non-biofilm forming isolates (P=0.0001). Additionally, the resistance to fluconazole, itraconazole and caspofungin was statistically, significantly higher in C. albicans with the capacity to form biofilm as compared to non-biofilm forming C. albicans.

Conclusion:

The present study highlights the prevalence of resistance to antifungal drugs among C. albicans which are not uncommon. Moreover, there was a high prevalence of INT1, ALS1, HWP1, SAP1 and PLB1 genes in C. albicans. The resistance to antifungal drugs was common among isolates with the capacity to form the biofilm. There was an association between the biofilm formation and virulence genes.

Two New 1,3,4-Oxadiazoles With Effective Antifungal Activity Against Candida albicans

Candida infections have become a serious public health problem with high mortality rates, especially in immunocompromised patients, since Candida albicans is the major opportunistic pathogen responsible for systemic or invasive candidiasis. Commercially available antifungal agents are restricted and fungal resistance to such drugs has increased; therefore, the development of a more specific antifungal agent is necessary. Using assays for antifungal activity, here we report that two new compounds of 1,3,4-oxadiazoles class (LMM5 and LMM11), which were discovered by in silico methodologies as possible thioredoxin reductase inhibitors, were effective against C. albicans. Both compounds had in vitro antifungal activity with MIC 32 μg/ml. Cytotoxicity in vitro demonstrated that LMM5 and LMM11 were non-toxic in the cell lines evaluated. The kinetic of the time-kill curve suggested a fungistatic profile and showed an inhibitory effect of LMM5 and LMM11 in 12 h that remained for 24 and 36 h, which is better than fluconazole. In the murine systemic candidiasis model by C. albicans, the two compounds significantly reduced the renal and spleen fungal burden. According to the SEM and TEM images, we hypothesize that the mechanism of action of LMM5 and LMM11 is directly related to the inhibition of the enzyme thioredoxin reductase and internally affect the fungal cell. In view of all in vitro and in vivo results, LMM5 and LMM11 are effective therapeutic candidates for the development of new antifungal drugs addressing the treatment of human infections caused by C. albicans.

A Predominance of Clade 17 Candida albicans Isolated From Hemocultures in a Tertiary Care Hospital in Thailand

Candida albicans is one of the most common human fungal pathogens. Candidemia has significant mortality globally. No epidemiological study of C. albicans based on multilocus sequence typing (MLST) has been conducted in Thailand. Therefore, MLST was used to study the molecular epidemiology of C. albicans blood strains in a large Thai teaching hospital. In vitro virulence phenotypes and antifungal susceptibility testing by broth microdilution were also conducted. Forty-six C. albicans blood strains from 37 patients were collected from the Department of Microbiology, Siriraj Hospital, in 2016 and 2017. Most patients (71.8%) were more than 60 years old, and the case fatality rate was 54.8%. The male-to-female ratio was 5:3. Thirty-four diploid sequence types (DSTs), including six new DSTs, were identified, with DST2514 (8.7%) and DST2876 (8.7%) as the most common DSTs. Strains were clustered into nine clades. Unlike other studies of C. albicans blood strains in Asia, clade 17 was the most common (13 strains, 28.3%). Sequential allelic changes were evident in sequential strains from one patient. All strains produced phospholipase and hemolysin, while none produced proteinase. The ability to form biofilm was found in 82.6% of the strains. Clade 17 strains showed significantly stronger hemolytic activity than non–clade 17 strains (69.2% versus 27.3%; p = 0.022). However, no significant association existed between clades and patient mortalities. All were susceptible or wild type to anidulafungin (MIC range = 0.015–0.12 and GM = 0.030), micafungin (MIC range = ≤ 0.008–0.015 and GM = 0.008), caspofungin (MIC range = 0.008–0.12 and GM = 0.036), and amphotericin B (MIC range = 0.25–0.5 and GM = 0.381). Only one strain was resistant to voriconazole (MIC range = ≤ 0.008 to ≥ 8 and GM = 0.010) and fluconazole (MIC range = 0.12–16 and GM = 0.398). In conclusion, a high prevalence of clade 17 C. albicans blood strains was found in Thailand, in contrast to other Asian countries. This unique finding might be explained by the strong hemolytic activity that is required for bloodstream infection of C. albicans.

Five-year profile of candidaemia at an Indian trauma centre: High rates of Candida auris blood stream infections

Candidaemia is a potentially fatal infection with varied distribution of Candida species and their antifungal susceptibility profiles. The recent emergence of Candida auris in invasive candidiasis is a cause for concern. This study describes the profile of candidaemia at an Indian tertiary care hospital and reports the emergence of C. auris. All patients diagnosed with candidaemia between 2012 and 2017 were studied. The isolates were identified using conventional methods, VITEK 2 and MALDI-TOF MS. The isolates not identified by MALDI-TOF were sequenced. Antifungal susceptibility testing was done by the CLSI broth microdilution method and VITEK 2. A total of 114 isolates of Candida species were analysed. Candida tropicalis (39.4%) was the most common species, followed by C. auris (17.5%), C. albicans (14%) and C. parapsilosis (11.4%). Notably, Diutina mesorugosa isolates (n = 10) were not identified by MALDI-TOF and were confirmed by sequencing. Furthermore, 45% (n = 9) C. auris strains exhibited low MICs of FLU (0.05-4 μg/mL) and the remaining 55% (n = 11) isolates had high MICs ≥ 64 μg/mL. Also, D. mesorugosa exhibited high MICs of FLU (32 μg/mL) in 2 isolates. A high rate of errors in antifungal susceptibility was noted with the VITEK 2 as compared to the CLSI method. Candida auris was the second most prevalent species causing candidaemia warranting infection control practices to be strengthened to prevent its spread.

Effects of Acetone Fraction From Buchenavia tomentosa Aqueous Extract and Gallic Acid on Candida albicans Biofilms and Virulence Factors

A promising anti-Candida activity of Buchenavia tomentosa extracts was recently described. In the present work, experiments were carried out to determine the fraction with higher antifungal activity from a B. tomentosa extract. Acetone fraction (AF) was obtained from the aqueous extract from dried leaves (5 min/100°C) and it was the most effective one. Gallic acid (GA) was identified by electrospray ionization mass spectrometry (ESI–MS) and also chosen to perform antifungal tests due to its promising activity on Candida albicans. Minimal inhibitory and fungicidal concentrations (MIC and MFC) were determined by broth microdilution technique. The effect on virulence factors of C. albicans was evaluated, and the cytotoxicity was determined. MIC₅₀ and MIC₉₀ values were both equal to 0.625 mg ml^-1 for AF and 2.5 and 5 mg ml^-1, respectively, for GA. AF and GA showed ability to inhibit C. albicans adherence and to disrupt 48 h-biofilm. AF and GA were effective in reducing the formation of hyphae of C. albicans SC5314. AF and GA decreased adherence of C. albicans to oral epithelial cells. AF and GA showed slight to moderate toxicity to Vero cells. This result suggests further studies for topic use of these compounds. AF, which contains a combination of several molecules, presented greater potential of antimicrobial activity than GA, with lower values of MIC and lower cytoxicity.

Global and Multi-National Prevalence of Fungal Diseases-Estimate Precision

Fungal diseases kill more than 1.5 million and affect over a billion people. However, they are still a neglected topic by public health authorities even though most deaths from fungal diseases are avoidable. Serious fungal infections occur as a consequence of other health problems including asthma, AIDS, cancer, organ transplantation and corticosteroid therapies. Early accurate diagnosis allows prompt antifungal therapy; however this is often delayed or unavailable leading to death, serious chronic illness or blindness. Recent global estimates have found 3,000,000 cases of chronic pulmonary aspergillosis, ~223,100 cases of cryptococcal meningitis complicating HIV/AIDS, ~700,000 cases of invasive candidiasis, ~500,000 cases of Pneumocystis jirovecii pneumonia, ~250,000 cases of invasive aspergillosis, ~100,000 cases of disseminated histoplasmosis, over 10,000,000 cases of fungal asthma and ~1,000,000 cases of fungal keratitis occur annually. Since 2013, the Leading International Fungal Education (LIFE) portal has facilitated the estimation of the burden of serious fungal infections country by country for over 5.7 billion people (>80% of the world's population). These studies have shown differences in the global burden between countries, within regions of the same country and between at risk populations. Here we interrogate the accuracy of these fungal infection burden estimates in the 43 published papers within the LIFE initiative.