Risk Factors and Outcomes of Recurrent Candidemia in Children: Relapse or Re-Infection?

Hospital distribution, seasonality, time trends and antifungal susceptibility profiles of all Aspergillus species isolated from clinical samples from 2015 to 2022 in a tertiary care hospital

BACKGROUND

Aspergillus species cause a variety of serious clinical conditions with increasing trend in antifungal resistance. The present study aimed at evaluating hospital epidemiology and antifungal susceptibility of all isolates recorded in our clinical database since its implementation.

METHODS

Data on date of isolation, biological samples, patients' age and sex, clinical settings, and antifungal susceptibility tests for all Aspergillus spp. isolated from 2015 to 2022 were extracted from the clinical database. Score test for trend of odds, non-parametric Mann Kendall trend test and logistic regression analysis were used to analyze prevalence, incidence, and seasonality of Aspergillus spp. isolates.

RESULTS

A total of 1126 Aspergillus spp. isolates were evaluated. A. fumigatus was the most prevalent (44.1%) followed by A. niger (22.3%), A. flavus (17.7%) and A. terreus (10.6%). A. niger prevalence increased over time in intensive care units (p-trend = 0.0051). Overall, 16 (1.5%) were not susceptible to one azole compound, and 108 (10.9%) to amphotericin B, with A. niger showing the highest percentage (21.9%). The risk of detecting A. fumigatus was higher in June, (OR = 2.14, 95% CI [1.16; 3.98] p = 0.016) and reduced during September (OR = 0.48, 95% CI [0.27; 0.87] p = 0.015) and October as compared to January (OR = 0.39, 95% CI [0.21; 0.70] p = 0.002. A. niger showed a reduced risk of isolation from all clinical samples in the month of June as compared to January (OR = 0.34, 95% CI [0.14; 0.79] p = 0.012). Seasonal trend for A. flavus showed a higher risk of detection in September (OR = 2.7, 95% CI [1.18; 6.18] p = 0.019), October (OR = 2.32, 95% CI [1.01; 5.35] p = 0.048) and November (OR = 2.42, 95% CI [1.01; 5.79] p = 0.047) as compared to January.

CONCLUSIONS

This is the first study to analyze, at once, data regarding prevalence, time trends, seasonality, species distribution and antifungal susceptibility profiles of all Aspergillus spp. isolates over a 8-year period in a tertiary care center. Surprisingly no increase in azole resistance was observed over time.

Risk factors, antifungal susceptibility, complications, and outcome of Candida auris bloodstream infection in a tertiary care center in the western region of Saudi Arabia

BACKGROUND

Candida auris, an emerging multidrug-resistant fungus species that grows as yeast, causes bloodstream infection, and is associated with high mortality rates. In this study, we identified risk factors associated with C. auris bloodstream infection, antifungal susceptibility pattern, complications, and outcome of the infection.

METHODS

This single-center cross-sectional retrospective study was conducted at King Abdulaziz Medical City, a tertiary care facility in Jeddah, Saudi Arabia, which included all patients 18 years or above who have had one or more blood cultures for C. auris between January 2021 and December 2022. We aimed to identify the risk factors associated with C. auris bloodstream infection, antifungal susceptibility patterns, complications, and outcomes at our center.

RESULTS

Forty-six patients with C. auris-positive blood cultures were included. All the patients had healthcare-associated infections. The mean age was 64.67 years, and the majority of patients were male (73.9 %). The most common concomitant hospital-acquired infections were skin and soft tissue infections (37 %), followed by hospital-acquired pneumonia (34.8 %) and intra-abdominal infections (26.1 %). The mean total white blood cell count, procalcitonin, and C-reactive protein was 10.5 ± 5.99 × 109/L, 2.63 ± 4.82 μg/L, and 90.3 ± 64.1 mg/L, respectively. Hypertension (73.9 %) was the most common comorbidity, followed by diabetes mellitus (58.7 %) and renal dysfunction (54.3 %). Risk factors associated with C. auris candidemia included antibiotic use (91.3 %), especially for > 14 days (78.3 %), C. auris colonization (60.9 %), use of central venous catheters, especially when the catheter was in place for >30 days (80.4 %), ICU admission in the last 30 days before C. auris-positive blood culture (93.5 %), especially for more than two weeks (76.1 %), mechanical ventilation (89.1 %), total parenteral nutrition (13 %), previous intra-abdominal surgery (30.4 %), and immunosuppressive therapy (56.5 %). A total of 97.8 % of C. auris isolates were resistant to fluconazole and 17.4 % were resistant to amphotericin B. Endocarditis and endophthalmitis were reported in one (2.2 %) patient each. The all-cause mortality at 30 days was 47.8 %.

CONCLUSION

Our study is one of the few studies available globally on C. auris bloodstream infection that investigated risk factors, antifungal susceptibility, complications, and outcomes. A thorough screening and risk assessment strategy should aid infection control, preventing it from becoming a major concern in the future.

Paradigm Shift: Candida parapsilosis sensu stricto as the Most Prevalent Candida Species Isolated from Bloodstream Infections with Increasing Azole-Non-Susceptibility Rates: Trends from 2015-2022 Survey

Candidemia is the fourth most common healthcare-related bloodstream infection. In recent years, incidence rates of Candida parapsilosis have been on the rise, with differences in prevalence and antifungal susceptibility between countries. The aim of the present study was to evaluate temporal changes in prevalence and antifungal susceptibility of C. parapsilosis among other species causing candidemia. All candidemia episodes from January 2015 to August 2022 were evaluated in order to depict time trends in prevalence of C. parapsilosis sensu stricto among all Candida species recovered from blood cultures as well as fluconazole- and voriconazole-non-susceptibility rates. Secondary analyses evaluated time trends in prevalence and antifungal non-susceptibility according to clinical settings. The overall prevalence of C. parapsilosis was observed to increase compared to the prevalence of other Candida species over time (p-trend = 0.0124). From 2019, the number of C. parapsilosis sensu stricto isolates surpassed C. albicans, without an increase in incidence rates. Overall rates of fluconazole- and voriconazole-non-susceptible C. parapsilosis sensu stricto were both 3/44 (6.8%) in 2015 and were 32/51 (62.7%) and 27/51 (52.9%), respectively, in 2022 (85% cross-non-susceptibility). The risk of detecting fluconazole- or voriconazole-non-susceptibility was found to be higher in C. parapsilosis compared to other Candida species (odds ratio (OR) = 1.60, 95% CI [1.170, 2.188], p-value < 0.0001 and OR = 12.867, 95% CI [6.934, 23.878], p-value < 0.0001, respectively). This is the first study to report C. parapsilosis sensu stricto as the most prevalent among Candida spp. isolated from blood cultures, with worrisome fluconazole- and voriconazole-non-susceptibility rates, unparalleled among European and North American geographical regions.

Short Course of Antifungal Therapy in Patients With Uncomplicated Candida Bloodstream Infection: Another Case of Less Is More in the Clinical Setting?

Background

The objective of this study was to compare the clinical outcomes of patients receiving a short course (SC) vs a prolonged course (PC) of antifungal therapy for uncomplicated Candida bloodstream infections (BSIs).

Methods

All episodes of uncomplicated Candida BSI from September 1, 2018, to August 31, 2020, were reviewed. We compared the primary (all-cause 90-day mortality) and secondary study end points (1-year recurrent Candida BSI and all-cause 1-year mortality) among patients who underwent SC (5-11 days) or PC (12-24 days) therapy using propensity score analysis with the inverse probability of treatment weighting (IPTW) method.

Results

A total of 114 patients with uncomplicated Candida BSI were included: 35 (30.7%) were classified into the SC group (median [interquartile range {IQR}], 9 [7-11] days) and 79 (69.3%) into the PC group (median [IQR], 14 [14-16] days). Patients in the SC group compared with the PC group had a higher rate of hospitalization in the surgical ward (40.0% vs 19.0%; P = .02) or septic shock at the time of Candida BSI onset (11.4% vs 1.3%; P = .03). The risk of 90-day mortality was not different between the SC and PC groups (n = 8 [22.9%] vs 17 [21.5%], respectively; IPTW-adjusted subdistribution hazard ratio [sHR], 0.67; 95% CI, 0.31-1.47; P = .20). The risk for recurrent Candida BSI within 1 year of completing therapy (IPTW-adjusted sHR, 1.07; 95% CI, 0.20-5.80; P = .94) or for all-cause 1-year mortality (IPTW-adjusted HR, 0.72; 95% CI, 0.35-1.50; P = .38) did not differ between groups.

Conclusions

Receiving a short vs prolonged course of antifungal therapy did not affect mortality or BSI recurrence in patients with uncomplicated candidemia.

Pediatric Candida Bloodstream Infections Complicated with Mixed and Subsequent Bacteremia: The Clinical Characteristics and Impacts on Outcomes

Background: Pediatricians face a therapeutic challenge when patients with Candida bloodstream infections (BSIs) simultaneously have positive bacterial culture. We aim to characterize the clinical characteristics of pediatric Candida BSIs complicated with mixed bacteremia and subsequent bacterial infections, risk factors and impacts on outcomes. Methods: All episodes of pediatric Candida BSIs between 2005 and 2020 from a medical center in Taiwan were reviewed. Mixed Candida/bacterial BSIs were defined as isolation of a bacterial pathogen from blood cultures obtained within 48 h before or after the onset of Candida BSI. The clinical features and impacts of mixed Candida/bacterial BSIs were investigated. Results: During the study period, 320 patients with a total of 365 episodes of Candida BSIs were identified and analyzed. Mixed Candida/bacterial BSIs were 35 episodes (9.6%). No significant difference was found between mixed Candida/bacterial BSIs and monomicrobial Candida BSIs in terms of patient demographics, Candida species distributions, most chronic comorbidities or risk factors. Patients with mixed Candida/bacterial BSIs were associated with a significantly higher risk of subsequent bacteremia (51.4% vs. 21.2%, p < 0.001) and a relatively higher candidemia-attributable mortality rate (37.2% vs. 22.4%, p = 0.061) than those with monomicrobial Candida BSIs. Mixed Candida/bacterial BSIs were not an independent risk factor of treatment failure or final mortality according to multivariate logistic regression analyses. Conclusions: The clinical significance of mixed Candida/bacterial BSIs in children included a longer duration of septic symptoms, significantly higher likelihood to have subsequent bacteremia, and relatively higher risk of candidemia attributable mortality.

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

Background

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

Methods

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

Results

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

Conclusions

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

Growing importance of urogenital candidiasis in individuals with diabetes: A narrative review

Both diabetes and fungal infections contribute significantly to the global disease burden, with increasing trends seen in most developed and developing countries during recent decades. This is reflected in urogenital infections caused by Candida species that are becoming ever more pervasive in diabetic patients, particularly those that present with unsatisfactory glycemic control. In addition, a relatively new group of anti-hyperglycemic drugs, known as sodium glucose cotransporter 2 inhibitors, has been linked with an increased risk for colonization of the urogenital region with Candida spp., which can subsequently lead to an infectious process. In this review paper, we have highlighted notable virulence factors of Candida species (with an emphasis on Candida albicans) and shown how the interplay of many pathophysiological factors can give rise to vulvovaginal candidiasis, potentially complicated with recurrences and dire pregnancy outcomes. We have also addressed an increased risk of candiduria and urinary tract infections caused by species of Candida in females and males with diabetes, further highlighting possible complications such as emphysematous cystitis as well as the risk for the development of balanitis and balanoposthitis in (primarily uncircumcised) males. With a steadily increasing global burden of diabetes, urogenital mycotic infections will undoubtedly become more prevalent in the future; hence, there is a need for an evidence-based approach from both clinical and public health perspectives.

Clinical and Microbiological Characteristics of Neonates with Candidemia and Impacts of Therapeutic Strategies on the Outcomes

Neonatal candidemia is associated with significant morbidities and a high mortality rate. We aimed to investigate the clinical characteristics of Candida bloodstream infections in neonates and the impact of therapeutic strategies on the outcomes. We identified all the neonates with candidemia from a medical center in Taiwan over an 18-year period (2003−2021) and analyzed them. Clinical isolates were confirmed by DNA sequencing, and antifungal susceptibility testing was performed. The prognostic factors associated with clinical treatment failure (30-day, all-cause mortality and persistent candidemia > 72 h after antifungal agents) and in-hospital mortality were analyzed using logistic regression modeling. A total of 123 neonates with 139 episodes of candidemia were included in the study. The median (IQR) gestational age and birth weight of the neonates with candidemia were 29.0 (26.0−35.0) weeks and 1104.0 (762.0−2055) g, respectively. The most common Candida spp. was Candida albicans (n = 57, 41.0%), followed by C. parapsilosis (n = 44, 31.7%), Candida guilliermondii (n = 12, 8.6%), and C. glabrata (n = 11, 7.9%). The overall susceptibility to fluconazole was 81.3%, and the resistant rates against other antifungal agents were less than 3%. The cumulative mortality rate at 7 and 30 days after the first episode of candidemia was 11.3% and 32.3%, respectively. The overall in-hospital mortality rate was 42.3%. The treatment outcomes did not change over the study period and were not affected by delayed initiation of antifungal agents. Multivariate analysis showed that delayed catheter removal (odds ratio [OR], 5.54; 95% confidence interval [CI]: 1.93−15.86, p = 0.001), septic shock (OR, 7.88; 95% CI: 2.83−21.93, p < 0.001), and multiple chronic comorbidities (OR, 8.71; 95% CI: 1.82−41.81, p = 0.007) were independently associated with the final in-hospital mortality. We concluded that the overall mortality of neonatal candidemia has remained consistently high over the past decade. Prompt early catheter removal and an aggressive treatment strategy for neonatal candidemia with septic shock would be critical to improving patient outcomes.

Role of Candida glabrata as nosocomial pathogen and its susceptibility to Fluconazole, Voriconazole, Caspofungin, Micafungin and Amphotericin B

Candida has different types that could cause bloodstream infections. A total number of 150 samples were collected from candidemia patients and examined. The Candida spp. Species isolated from blood samples were analysed. These were identified by culturing the species using different media, namely the chromogenic agar test. Then, the virulence factors of all samples were tested. The Candida glabrata isolates were tested with six commercial antifungal drugs. C. glabrata 67 (44.6%), C. albicans 34 (22.6%), C. krusei 18 (12%), C. tropicalis 17 (11.3%), and C. parasilosis 14 (9.3%). the production of phospholipase ranged between 0.63-0.99 mm. It was found that 96% of the species showed phospholipase activity in aerobic conditions. The protease activities of Candida spp. Isolates were experimentally tested by area of inhibition around the colonies, where 59.3% had the double (++) protease activity, 31.4% with (+) grade, and 9.3% had (–) grade or clear zone around the colony. The hemolytic capacity ranged from 0.69-0.89 in the optimum aerobic environments. Finally, 38.33% of the isolated Candida spp. were positive and 61.67% negative for biofilm formation. Out of the total positive Candida spp. for biofilm formation, 21.73% were strong biofilm producers, and 78.27% were weak. Minimum fungicidal concentration (MFC) of Fluconazole for C. glabrata isolates was not appropriate (NA) due to the occurrence of low inhibition tested for species. Micafungin exhibited the lowest fungicidal activity against C. glabrata ranging from 0.03 - 0.125, while Fluconazole showed the highest.

Combination Therapy to Treat Fungal Biofilm-Based Infections

An increasing number of people is affected by fungal biofilm-based infections, which are resistant to the majority of currently-used antifungal drugs. Such infections are often caused by species from the genera Candida, Aspergillus or Cryptococcus. Only a few antifungal drugs, including echinocandins and liposomal formulations of amphotericin B, are available to treat such biofilm-based fungal infections. This review discusses combination therapy as a novel antibiofilm strategy. More specifically, in vitro methods to discover new antibiofilm combinations will be discussed. Furthermore, an overview of the main modes of action of promising antibiofilm combination treatments will be provided as this knowledge may facilitate the optimization of existing antibiofilm combinations or the development of new ones with a similar mode of action.

Successful in-vivo treatment of mice infected with Candida glabrata using silver nanoparticles

The current study describes the production of silver nanoparticles (AgNPs) to treat Candida glabrata infections. The method involved incubation of silver nitrate (AgNO3) with Aspergillus terreus using a green and straightforward route. The production of AgNPs was confirmed through a color change from transparent yellow to brown as well as by ultraviolet-visible (UV-VIS) spectroscopy. The surface morphology of AgNPs was assessed using a scanning electron microscope. The antifungal activity of AgNPs against C. glabrata was investigated in the serum of 20 infected mice. The mice were divided into four groups, and the level of cytokines: IL-4 and IFN-γ were examined after 21 days. The atomic force microscopy confirmed that the average diameter of AgNPs was 25.1 nm, which is appropriate for delivering silver nanoparticles to treat animals' infection. The concentration of cytokines IL-4 and IFN-γ were significantly (P < 0.05) higher in the C. glabrata-infected group than in the control group. While the cytokines level remained close to average concentration in mice administrated with AgNPs, such a result was comparable with the fourth group of mice (Candida-treated Aspergillus) after treatment with AgNPs.