Distribution and susceptibility of Candida species isolated in the Medical University of Debrecen

Epidemiology, clinical characteristics, outcome and biofilm forming properties in candidaemia: A single-centre retrospective 4-year analysis from Hungary

BACKGROUND

Candidaemia is a life-threatening disease that is associated with high mortality, especially in intensive care units (ICUs). The number of comprehensive studies dealing with the epidemiologic characteristics of biofilm-related properties is limited.

OBJECTIVE

This study evaluated the clinical characteristics of candidaemia, to assess the biofilm-forming properties of isolates, and to identify the risk factors of mortality.

PATIENTS AND METHODS

A total of 149 candidaemia episodes from the University of Debrecen, Clinical Centre, between January 2020 and December 2023 were investigated retrospectively. The susceptibility of Candida isolates to fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin was evaluated and compared to the susceptibility of 1-day-old biofilms. Multivariate logistic regression analysis was applied to identify the independent predictors of 30-day mortality rate.

RESULTS

The most common Candida species was Candida albicans (41%), followed by C. parapsilosis (20%), C. glabrata (14%), C. tropicalis (13%), rare Candida species (7%), and C. krusei (5%). Sixty-six percent of Candida isolates were biofilm formers and 44% had high metabolic activity. The 30-day mortality rate was 52%, which was higher in ICUs (65%). The logistic regression analysis revealed several factors significantly influencing mortality including ICU admission (odds ratio [OR] 2.99, 95% confidence interval [CI] 1.17-8.04, p = 0.025), fluconazole treatment (OR 4.12, 95% CI 1.62-11.42, p = .004), and pneumonia (OR 0.261, 95% CI 0.1-0.67, p = .006).

CONCLUSIONS

This comprehensive analysis supports the better characterisation of candidaemia in healthcare settings, which ultimately may reduce mortality among patients.

Molecular epidemiology, virulence factors, and antifungal susceptibility of Candida inconspicua strains isolated from clinical samples in Turkey

In this study, it was aimed to evaluate the molecular epidemiology, virulence factors, and antifungal susceptibility of clinical Candida inconspicua isolates. All isolates were identified by phenotypic methods and sequence analysis of ITS 1-2, D1/D2, EF-1 alpha. Proteinase, phospholipase, and esterase activities, biofilm formation, and antifungal susceptibilities were determined. All thirty isolates identified as Candida norvegensis by phenotypic methods were reidentified as C. inconspicua by sequence analysis, demonstrating the inadequacy of phenotypic methods to differentiate these 2 species. The gene regions examined in terms of determining evolutionary relatedness did not show intraspecies nucleotide variations. Therefore, different molecular approaches are needed to evaluate molecular epidemiology. Esterase, phospholipase, and biofilm formation were found to be positive in 100%, 100%, and 36.6% of the strains, respectively. The MIC₅₀/MIC₉₀ values for fluconazole and flucytosine were found to be higher than the other tested antifungals, which should be taken into account in the treatment.

Unveiling the Hungarian landscape of laboratory and clinical management capacities for invasive fungal infections: navigating the frontlines against fungal menaces

Background

Antifungal diagnostic capacity has been documented in various countries, there is a lack of comprehensive research on clinical mycology diagnostics and treatment in Hungary.

Methods

We conducted an online survey encompassing questions that explored various aspects of the mycology diagnostic and antifungal therapy-related information. The survey aimed to gather details about institutional profiles, perceptions of invasive fungal infections (IFIs), and access to microscopy, culture, serology, antigen detection, molecular testing, and therapeutic drug monitoring.

Results

As of May 2023, a total of 17 institutions responded to the questionnaire. Seven participants categorized the institutional incidence of IFI as 'very low', four as 'low', and six as 'mild'. The majority of centers identified Candida spp. (94%) and Aspergillus spp. (82%) as the most prevalent fungal pathogens. Nearly half of the laboratories (47%) reported using matrix-assisted laser desorption/ionization-time of flight mass spectrometry for identification. All institutions had access to microscopy and culture-based diagnostic approaches. A significant number of centers had access to antigen detection (71%) and various molecular assays (59%). Regarding antifungal agents, all reporting sites used at least one triazole, with voriconazole (77%) being the most common mold-active azole. Furthermore, 71% of the centers applied at least one formulation of amphotericin B, and 65% to one echinocandin. However, only 18% of the centers used 5-flucytosine.

Conclusion

Resource availability for diagnosing and treating IFI in Hungary varies across hospitals based on location. Surveys help identify gaps and limitations in this area. To address these challenges, interregional cooperation within Hungary could be a facilitating strategy.

Burden of serious fungal diseases in Hungary

Valid data on the prevalence of serious fungal diseases are difficult to derive as in most countries these conditions are not reportable infections. To assess the burden of these infections in Hungary prevalence estimates from international peer-reviewed papers and population statistics were utilised. In the intensive care unit (ICU) population at least 370 cases of serious yeast and 52 mould infections can be expected yearly. The total number of candidaemia cases may be as high as 1110 annually. In patients with acute leukaemia and recipients of haematopoietic stem cell and solid organ transplants the predicted incidence is more than 55 every year. Recurrent vulvovaginal candidiasis--though not a life-threatening condition--can adversely affect the quality of life of more than 177,000 Hungarian women. According to organisation for economic co-operation and development (OECD), 4.7% of total population older than 15 will suffer from chronic obstructive pulmonary disease (COPD) and 4.4% from asthma, adding another very broad risk group to the aforementioned categories susceptible for mycotic complications. Here more than 17,000 can have severe asthma with fungal sensitisation (SAFS) and more than 13,000 are at risk for developing allergic bronchopulmonary aspergillosis (ABPA). The incidence of dermatomycoses and other superficial fungal infections is even more difficult to assess but--according to international estimations--can affect around 14.3% of the total population. More than 1.6 million Hungarians may suffer from fungal diseases annually, with 33,000 cases being life threatening or very serious. This is an under-recognised problem of special importance for public health.

Serum interleukin-6 levels in murine models of Candida albicans infection

Two Balb/C mouse models of Candida infection were used to detect serum interleukin-6 (IL-6) responses. The first model used systemic infection by Candida albicans ATCC 10231 strain infected through the lateral tail vein of mice without any specific pretreatment. The median Candida burdens of the kidneys were 1.5 × 106 CFU/ml 24 h postinoculation (p.i.) and 1.2 × 107 CFU/ml 72 h p.i., while median serum IL-6 levels were 479.3 pg/ml and 934.5 pg/ml, respectively. The Candida burden showed significant correlation with serum IL-6 24 h p.i. (R2 = 0.6358; P = 0.0082) but not 72 h p.i.The second model was a mouse vaginitis model applying intravaginal inoculation of mice pretreated with subcutaneous estradiol-valerate (10 mg/ml) 3 days before infection. Candida cell count in vaginal lavage fluid was 2.8 × 106 CFU/ml 24 h p.i. and 1.4 × 108 CFU/ml 72 h p.i. Serum IL-6 response was detected in 4 of 15 mice 24 h p.i. and 9 of 15 mice 72 h p.i. Even the responders had low IL-6 serum levels (mean values 29.9 pg/ml and 60.1 pg/ml, respectively) not correlating with Candida cell count in vaginal lavage fluid.In conclusion, serum IL-6 had strong relationship with systemic C. albicans infection while the local C. albicans infection of the vagina led to partial, prolonged and limited serum IL-6 response.

[Urinary tract infection by Candida species]

OBJECTIVES

To determine the frequency and characteristics of urinary tract infection (UTI) by Candida in diabetic patients (with and without symptoms) and to compare them with non-diabetic patients (with and without symptoms).

DESIGN

Longitudinal, descriptive, and observational study.

SETTING

Study conducted at the "Dr Ignacio Chavez" Clinic of family medicine, ISSSTE: Mexico.

PARTICIPANTS

There were 2 kinds of patients; 1 with diabetes mellitus diagnosis (DM) with and without clinical picture of probable urinary tract infection (UTI), and 1 without DM and with and without clinical picture of probable UTI.

MAIN MEASUREMENTS

A urine culture and a confidential questionnaire were administered to find the presence of urinary symptoms and likely risk factors associated with the infection. To associate these risks, the chi2 statistical method was used, with significance at 95% and Fisher's Exact Test for small frequencies, using the EpiInfo V.6.0 program.

RESULTS

Two hundred thirty seven patients between 28 and 82 years old were included. The prevalence of urinary infection by Candida was 5.1%, but only 33% of these had C albicans. There was no association between candidiasis and factors like age, sex, or presence of DM, but it was related to previous treatments, previous UTI and the evolution time of DM.

CONCLUSIONS

The conscious search by both doctor and laboratory for Candida micro-organisms as factors causing UTI is important. This is especially so in those patients with factors of risk that may condition Candida's presence.

Restriction enzyme analysis of ribosomal DNA shows that Candida inconspicua clinical isolates can be misidentified as Candida norvegensis with traditional diagnostic procedures

We identified 29 yeast isolates from 22 patients using the API ID32C panel. Twenty-eight of these isolates were Candida norvegensis and one was C. inconspicua. Although C. norvegensis is considered a pseudohypha-producing species, only one isolate produced pseudohyphae. Restriction enzyme analysis of PCR-amplified ribosomal DNA with four different enzymes proved that all isolates were C. inconspicua.