Evaluation of candidemia risk factors and Candida species distribution in intensive care units among patients with and without COVID-19.

OBJECTIVES: To assess the risk variables related to the types of candidemia for each patient, who was admitted into the intensive care unit regardless of the patient with or without complete diagnosis of COVID-19, during the period of March 2019 to December 2022. METHODS: The evaluation comparison of demographic and clinical data of COVID-19 positive and negative patients with candidemia confirmed in blood, 113 cases were assessed. Variables such as gender, age, age of hospitalization, history of hospitalization, concurrently infection, The acute physiology and chronic health evaluation-II scores, comorbidity checking, intubation, central venous catheter use, parenteral nutrition use, steroid use, antibiotic use, lymphopenia, and laboratory variables were evaluated. Candida species distribution, antifungal susceptibility in blood culture were determined. RESULTS: Coronavirus disease-19 was present in 62.8% of cases confirmed candidemia, and these cases were significantly different from COVID-19 negative cases. Significance was found in more intubation, central venous catheter use, parenteral nutrition, and steroid therapy in Group 2. There was no significance with species distribution and associated infection. In total, COVID-19 positive had higher hemoglobin, aspartate aminotransferase, alanine transaminase, and white blood cell levels, which may be associated with the possibility of revealing and controlling candidemia. CONCLUSION: Candida albicans and Candida Parapsilosis (C. parapsilosis) are the species seen in infected COVID-19 patients, while C. parapsilosis and Candida tropicalis are found in non-COVID-19 ones. Risk factors were intubation, parenteral nutrition, central venous catheter, and steroid in the COVID-19 group.

Cytological and microbiological investigations of professional hygiene efficiency in patients with generalized periodontitis.

OBJECTIVE: Aim: The purpose of this study is to assess the impact of occupational hygiene procedures for microbiological and cytological contents of periodontal pockets. PATIENTS AND METHODS: Material and Methods: Cytological and microbiological content of the periodontal pockets before treatment and after professional hygiene procedures including scaling with hand instruments and root cementum polishing have been investigated in patients with periodontitis. RESULTS: Results: According to obtained data it can be resumed that in periodontitis patients with the depth of pockets 3-5,5 mm before professional hygiene all the pockets contain great number of Cocci, Spirochetes, Candida Albicans, Flagellated rods and Protozoa species. It was proved by revealing of small amount of Polymorphonuclear leukocytes with active phagocytosis. After scaling and planing of the roots, a decrease in the number of Protozoa and Candida Albicans was observed in 97% and 72% of the investigated cells, respectively. CONCLUSION: Conclusions: Cytological and microbiological content of periodontal pockets before treatment and after professional hygiene procedures including scaling and root planning testify to the level of local protective mechanisms, especially process of phagocytosis and virulence of microbial species in periodontal pockets.

Case report: Chronic Candida albicans meningitis: a rare entity diagnosed by metagenomic next-generation sequencing.

The aetiology of chronic aseptic meningitis is difficult to establish. Candida meningitis in particular is often diagnosed late, as cerebrospinal fluid (CSF) work-up and imaging findings are nonspecific. A 35-year-old patient with chronic aseptic meningitis, for which repeated microbiological testing of CSF was unrevealing, was finally diagnosed with Candida albicans (C. albicans) meningitis with cauda equina involvement using metagenomic next-generation sequencing (mNGS). This report highlights the diagnostic challenges and the difficulties of treating shunt-associated fungal meningitis.

Evaluation of some immunological markers in co-infection of COVID-19 with thrush candidiasis.

OBJECTIVE: COVID-19 infection poses significant risks, including life-threatening consequences and fungus synchronization, making it a significant concern. This study seeks to assess the effect of concurrent infection of COVID-19 with Thrush Candida albicans on the patient's health state by measuring the proportion of immune cells and certain interleukins such as IL-8, -10, -17, and -33. METHODS: The study involved 70 patients (30 patients with COVID-19, 17 patients with thrush candidiasis, and 23 patients with Thrush Candida albicans) and 50 healthy individuals as a control group. COVID-19 was identified using RT-PCR, while C. albicans were identified through culture media, biochemical testing, and oral swabs. Ruby equipment and ELISA kits were used for blood counts and interleukin detection. RESULTS: COVID-19, thrush candidiasis, and Thrush Candida albicans infections occur in a wide range of age groups (4-80 years), with no significant differences between sexes (p>0.05). Immunologically, our study found that Thrush Candida albicans patients had the highest rate of neutrophils (89.6%) and basophils (2.01%), while corona patients had the highest percentage of lymphocytes (70.12%) and eosinophils (7.11%), and patients with thrush candidiasis had the highest percentage of monocytes. Thrush Candida albicans patients showed increased IL-8 (56.7 pg/mL) and IL-17 (101.1 pg/mL) concentrations, with the greatest concentration of IL-33 (200.5 pg/mL) in COVID-19, and a decrease in the level of IL-10 in patient groups compared with controls. CONCLUSION: Patient groups showed increased neutrophils, lymphocytes, monocytes, and IL-8 levels, with a significant linear association between proinflammatory interleukins and these cells.

Renal candidiasis associated with papillary necrosis in a captive tiger (Panthera tigris).

A 14-year-old male tiger developed anorexia with elevated blood urea nitrogen and creatinine levels. The patient had a palpable abdominal mass and demonstrated neutrophilic leukocytosis and anaemia. Leukocytes, yeast and bacteria were present in the urine. The animal was non-responsive to therapy and was subsequently euthanised. Extensive acute renal papillary necrosis (RPN) with pyelonephritis, chronic nephritis and polycystic renal disease were evident during gross and microscopic pathology examinations. The histologic occurrence of fungal spores and pseudohyphae morphologically consistent with Candida species were observed within the necrotic papillary regions of the kidney and within multiple foci of mild parakeratotic hyperkeratosis present in the gingiva and tongue. Candida albicans along with a slight growth of Escherichia coli were recovered from kidney cultures. Possible contributory factors for the renal candidiasis and associated RPN include predisposing oral candidiasis, polycystic renal disease, ischaemic nephrosclerosis, age-associated or other forms of immunodeficiency and therapy with meloxicam, a non-steroidal anti-inflammatory drug. The absence of apparent lower urinary tract involvement coupled with the presence of intravascular renal 'Candida emboli' suggest that chronic oral candidiasis was the probable source of the kidney infection.

Oral Candida albicans strain diversity and maintenance in HIV positive women in South Africa.

OBJECTIVE: This study investigated C. albicans strain diversity and maintenance in the oral cavity of HIV positive women over a 6 month period. STUDY DESIGN: C. albicans strains were isolated from 17 HIV positive women at Charlotte Maxeke Academic Hospital, Johannesburg at 3 intervals over a 6 month period. Strains were genotyped using ABC and Multilocus Sequence Typing (MLST) techniques. In the MLST technique, for each strain, a Diploid Sequence Type (DST) number was obtained. Using cluster analysis, an Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram and a matrix of strain similarities were generated. Strains were also compared to the previous South African isolates documented in the MLST database. RESULTS: Ninety four percent of women carried the same ABC genotype for 6 months. MLST technique, showed that ten women (58.8%) carried the same DST at 2 visits, while seven (41.2%) carried different DST at all visits. Further analysis showed that 64.7% of women were recolonised with different strains and 35.3% carried the same strains of C. albicans with heterozygosity. A total of 40 diploid sequence types were identified of which 27 DSTs were unique to this study group that were added to the MLST database. Most of the strains were closely related to previously isolated strains from South Africa. CONCLUSION: Recolonization of the oral cavity with different strains and microevolution of the original strains of C. albicans can occur, which can be a potential problem for HIV patients, in whom highly virulent and drug resistant strains can emerge.

Association between sleep pattern, salivary cariogenic bacteria and fungi populations, pH and buffering capacity in children: A comparative study.

BACKGROUND: Sleep quality has a significant impact on a child's health and is linked to oral and systemic diseases. It affects the circadian rhythm, which plays a crucial role in regulating the balance of the endocrine and hormonal systems. Current research has focused on exploring its role in the development of caries, which is influenced by inherent oral factors such as the composition of the oral microbiome and pH levels. OBJECTIVES: This study aimed to investigate the relationship between bacterial population, pH, and buffering properties of saliva and sleep patterns in 8- to 12-year-old children. MATERIAL AND METHODS: This cross-sectional study was conducted on 85 elementary school children aged 8-12 years. After obtaining written consent, non-stimulating saliva samples were collected using the spitting method. The participants' sleep pattern information was obtained with the use of the Persian version of the Children's Sleep Habits Questionnaire (CSHQ). Based on the results of the CSHQ, the participants were divided into 2 groups: those with appropriate sleep patterns; and those with inappropriate sleep patterns. The study compared the bacterial population of Streptococcus mutans, Lactobacillus spp. and Candida albicans, as well as the buffering capacity and pH of the saliva between the 2 groups. The statistical analysis employed the χ2 test, the independent samples t-test and Spearman's correlation. RESULTS: The group with inappropriate sleep patterns had significantly lower pH and buffering capacity (p < 0.001) and significantly higher colony counts of Lactobacillus and S. mutans (p < 0.001 and p = 0.012, respectively). There was no association between C. albicans and sleep patterns (p = 0.121). CONCLUSIONS: Inappropriate sleep patterns increase the population of caries-causing bacteria and reduce salivary pH and buffering capacity. This can be a significant factor in the development of dental caries in children aged 8-12 years.

Epidemiological patterns of candidaemia: A comprehensive analysis over a decade.

BACKGROUND: The prevalence of fungal bloodstream infections (BSI), especially candidaemia, has been increasing globally during the last decades. Fungal diagnosis is still challenging due to the slow growth of fungal microorganisms and need for special expertise. Fungal polymicrobial infections further complicate the diagnosis and extend the time required. Epidemiological data are vital to generate effective empirical treatment strategies. OBJECTIVES: The overall aim of this project is to describe the epidemiology of monomicrobial candidaemia and polymicrobial BSI, both with mixed fungaemia and with mixed Candida/bacterial BSIs. METHODS: We conducted a single-centre retrospective epidemiological study that encompasses 950,161 blood cultures during the years 2010 to 2020. The epidemiology of monomicrobial and polymicrobial candidaemia episodes were investigated from the electronic records. RESULTS: We found that 1334 candidaemia episodes were identified belonging to 1144 individual patients during 2010 to 2020. Candida albicans was the most prevalent species detected in candidaemia patients, representing 57.7% of these episodes. Nakaseomyces (Candida) glabrata and Candida parapsilosis complex showed an increasing trend compared to previous studies, whereas Candida albicans demonstrated a decrease. 19.8% of these episodes were polymicrobial and 17% presented with mixed Candida/bacterial BSIs while 2.8% were mixed fungaemia. C. albicans and N. glabrata were the most common combination (51.4%) in mixed fungaemia episodes. Enterococcus and Lactobacillus spp. were the most common bacteria isolated in mixed Candida/bacterial BSIs. CONCLUSIONS: Polymicrobial growth with candidaemia is common, mostly being mixed Candida/bacterial BSIs. C. albicans was detected in more than half of all the candidaemia patients however showed a decreasing trend in time, whereas an increase is noteworthy in C. parapsilosis complex and N. glabrata.

The characteristics of microbiome in the upper respiratory tract of COVID-19 patients.

BACKGROUND: Co-infection with other pathogens in coronavirus disease 2019 (COVID-19) patients exacerbates disease severity and impacts patient prognosis. Clarifying the exact pathogens co-infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is premise of the precise treatment for COVID-19 patients. METHODS: Sputum samples were collected from 17 patients in the COVID-19 positive group and 18 patients in the COVID-19 negative group. DNA extraction was performed to obtain the total DNA. Sequencing analysis using 16S and ITS rRNA gene was carried out to analyze the composition of bacterial and fungal communities. Meanwhile, all the samples were inoculated for culture. RESULTS: We did not observe significant differences in bacterial composition between the COVID-19 positive and negative groups. However, a significantly higher abundance of Candida albicans was observed in the upper respiratory tract samples from the COVID-19 positive group compared to the COVID-19 negative group. Moreover, the Candida albicans strains isolated from COVID-19 positive group exhibited impaired secretion of aspartyl proteinases. CONCLUSION: COVID-19 positive patients demonstrate a notable increase in the abundance of Candida albicans, along with a decrease in the levels of aspartyl proteinases, indicating the alteration of microbiota composition of upper respiratory tract.

Lower (1,3)-beta-d-glucan sensitivity and in vitro levels in Candida auris and Candida parapsilosis strains.

OBJECTIVES: The serum (1,3)-beta-d-glucan (BDG) assay gives quicker results and has higher sensitivity than blood cultures, therefore it is advised for early diagnosis of invasive candidemia and/or discontinuation of empirical therapy. Its sensitivity may depend on different factors. The aim of our study was to analyse the in vitro and in vivo BDG levels in clinical isolates of three species of Candida responsible for candidemia. METHODS: C. albicans, C. parapsilosis, and C. auris strains were collected from blood cultures of patients who had a concurrent (-1 to +3 days) serum BDG test (Fungitell assay). Supernatants of all strains were tested in quadruplicate for BDG levels. RESULTS: Twenty-two C. auris, 14 C. albicans, and ten C. parapsilosis strains were included. The median BDG levels in supernatants were 463 pg/mL (interquartile range [IQR] 379-648) for C. auris, 1080 pg/mL (IQR 830-1276) for C. albicans, and 755 pg/mL (IQR 511-930) for C. parapsilosis, with the significant difference among the species (p < 0.0001). Median serum BDG levels (IQR) were significantly lower in case C. auris and C. parapsilosis vs. C. albicans (p < 0.0001), respectively, 50 pg/mL (IQR 15-161) and 57 pg/mL (IQR 18-332), vs. 372 pg/mL (IQR 102-520). Sensitivity of serum BDG was 39% (95% confidence interval [CI], 18-64) in case of C. auris, 30% (95% CI, 8-65) C. parapsilosis and 78% (95% CI, 49-94) C. albicans candidemia. DISCUSSION: In our centre C. auris and C. parapsilosis strains have lower BDG content as compared with C. albicans, with a potential impact on serum BDG performance for the diagnosis of candidemia.

The effect of root canal preparation tapers on planktonic bacteria and biofilm reduction in the apical third: A correlative microtomography and microbiological laboratory study.

AIM: To evaluate the influence of different preparation tapers on the reduction in planktonic bacteria and biofilms of Enterococcus faecalis and Candida albicans in the apical third (4 mm) of the mesial roots of mandibular molars, correlating decontamination with canal shape. METHODOLOGY: After microtomography analysis for morphological standardization of the canals, 48 mandibular molar roots, each containing two canals (96 canals), were contaminated with E. faecalis and C. albicans and divided into four groups (n = 11) for canal instrumentation using ProDesign Logic 2 files with different tapers G (.03): # 25.03; G (.04): # 25.04; G (.05): # 25.05; and G (.06): # 25.06 and irrigation with 2.5% sodium hypochlorite. Four roots were examined under a scanning electron microscope (SEM) to qualitatively assess biofilm formation. Eight roots were used as the negative control group (samples were not contaminated). Bacteriological samples were taken exclusively from the apical third of the roots before and after chemical-mechanical preparation and bacterial counts were determined (CFU/mL). The final micro-CT scan was used to quantify the volume variation and unprepared canal area in the apical third. Statistical analysis was performed using the Kruskal-Wallis, Student-Newman-Keuls and Wilcoxon tests for analysis of microbiological data. anova and the Tukey or Games-Howell test were used for analysis of micro-CT data and Spearman's test for correlations (α = 5%). RESULTS: All groups showed a significant reduction in bacteria (p < .05), with no statistically significant difference between groups. There was no significant difference in per cent volume increase between groups. The unprepared area (Δ%) was affected by the file used (p = .026) and was significantly lower for G (.06) compared to G (.03). There was no statistically significant correlation among bacterial reduction, volume and unprepared area (p > .05). CONCLUSION: The different preparation tapers influenced root canal shaping in the apical third but did not improve decontamination in this region.

Magnetic Removal of Candida albicans Using Salivary Peptide-Functionalized SPIONs.

Purpose: Magnetic separation of microbes can be an effective tool for pathogen identification and diagnostic applications to reduce the time needed for sample preparation. After peptide functionalization of superparamagnetic iron oxide nanoparticles (SPIONs) with an appropriate interface, they can be used for the separation of sepsis-associated yeasts like Candida albicans. Due to their magnetic properties, the magnetic extraction of the particles in the presence of an external magnetic field ensures the accumulation of the targeted yeast. Materials and Methods: In this study, we used SPIONs coated with 3-aminopropyltriethoxysilane (APTES) and functionalized with a peptide originating from GP340 (SPION-APTES-Pep). For the first time, we investigate whether this system is suitable for the separation and enrichment of Candida albicans, we investigated its physicochemical properties and by thermogravimetric analysis we determined the amount of peptide on the SPIONs. Further, the toxicological profile was evaluated by recording cell cycle and DNA degradation. The separation efficiency was investigated using Candida albicans in different experimental settings, and regrowth experiments were carried out to show the use of SPION-APTES-Pep as a sample preparation method for the identification of fungal infections. Conclusion: SPION-APTES-Pep can magnetically remove more than 80% of the microorganism and with a high selective host-pathogen distinction Candida albicans from water-based media and about 55% in blood after 8 minutes processing without compromising effects on the cell cycle of human blood cells. Moreover, the separated fungal cells could be regrown without any restrictions.

A culture-free biphasic approach for sensitive and rapid detection of pathogens in dried whole-blood matrix.

Blood stream infections (BSIs) cause high mortality, and their rapid detection remains a significant diagnostic challenge. Timely and informed administration of antibiotics can significantly improve patient outcomes. However, blood culture, which takes up to 5 d for a negative result, followed by PCR remains the gold standard in diagnosing BSI. Here, we introduce a new approach to blood-based diagnostics where large blood volumes can be rapidly dried, resulting in inactivation of the inhibitory components in blood. Further thermal treatments then generate a physical microscale and nanoscale fluidic network inside the dried matrix to allow access to target nucleic acid. The amplification enzymes and primers initiate the reaction within the dried blood matrix through these networks, precluding any need for conventional nucleic acid purification. High heme background is confined to the solid phase, while amplicons are enriched in the clear supernatant (liquid phase), giving fluorescence change comparable to purified DNA reactions. We demonstrate single-molecule sensitivity using a loop-mediated isothermal amplification reaction in our platform and detect a broad spectrum of pathogens, including gram-positive methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteria, gram-negative Escherichia coli bacteria, and Candida albicans (fungus) from whole blood with a limit of detection (LOD) of 1.2 colony-forming units (CFU)/mL from 0.8 to 1 mL of starting blood volume. We validated our assay using 63 clinical samples (100% sensitivity and specificity) and significantly reduced sample-to-result time from over 20 h to <2.5 h. The reduction in instrumentation complexity and costs compared to blood culture and alternate molecular diagnostic platforms can have broad applications in healthcare systems in developed world and resource-limited settings.

Identificación de cepas del complejo Candida albicans aisladas de muestras clínicas en la región de Valparaíso, Chile / Identification of strains of the Candida albicans complex isolated clinical samples in the Valparaíso region, Chile

Introducción: C. albicans es reconocida como la especie más virulenta del género y representa la causa más frecuente de candidiasis en humanos. A nivel taxonómico, C.albicans se clasifica como un complejo de especies estrechamente relacionadas que incluye a C. albicans sensu stricto (s.s), C. dubliniensis y C. africana. Objetivo: identificar las especies del complejo C. albicans aisladas desde distintas muestras de pacientes de la quinta región de Valparaíso. Materiales y método: Se identificaron 103 cepas del complejo C. albicans, aisladas desde muestras superficiales y profundas durante el año 2020. La identificación se realizó en base a morfofisiología y la amplificación del gen HWP1. Resultados: Se identificaron 100 cepas como C. albicans s.s, 2 como C. dubliniensis y 1 como C. africana. Dentro de las cepas identificadas como C. albicans s.s se observaron cuatro patrones de tamaños de fragmentos genéticos. Conclusiones: C. albicans s.s fue la especie más frecuente y en base al genotipo de HPW1 se describen cuatro patrones ( H1 a H4). (AU)

Introduction: C. albicans is recognized as the most virulent species of the genus and represents the major cause of candidiasis in humans. At the taxonomic level, C. albicansis classified as a complex of closely related species that includes C. albicans sensu stricto (s.s), C. dubliniensis, and C. africana. Objective: to identify the species of the C. albicans complex isolated from different samples of patients from the fifth region of Valparaíso. Materials and method: 103 strains of the C. albicans complex were identified, isolated from superficial and deep samples during the year 2020. The identification was carried out based on morphophysiology and the amplification of the HWP1 gene. Results: 100 strains were identified as C. albicans s.s, 2 as C. dubliniensis and 1 as C. africana. Within the strains identified as C. albicans s.s, 4 patterns of fragment sizes were observed. Conclusions: C. albicans s.s was the most frequent species and based on the HPW1 genotype, four patterns are described (H1 to H4).(AU)

[The study of microbiota in patients with bullous lesions of the oral mucosa]. / Izuchenie mikrobioty slizistoi obolochki rta u patsientov s bulleznymi porazheniyami.

THE AIM OF THE STUDY: The study by the method of tissue polymerase chain reaction of the species composition of the microbiota of lesions of the oral mucosa in patients with bullous lesions. MATERIAL AND METHODS: Biopsy specimens of the oral mucosa of 51 patients were studied by the polymerase chain reaction method, of which 14 patients with pemphigus vulgaris, 17 patients with pemphigoid bullosa, and 20 patients with the bullous form of ruber lichen planus. 4 types of microorganisms have been identified - Fusobacterium, Streptococcus pneumoniae, Candida albicans, Ureaplasma spp. and viruses - Human Papillomavirus 16, Epstein-Barr virus and Citomegalovirus. RESULTS: In the study of the microbiota of bullous lesions, associations of microorganisms and viruses were established in a significant number of cases. Associations of Str.pneumoniae and C. albicans were quite common in patients with pemphigus vulgaris in 26.3%, pemphigoid bullosa in 20.0%, and in patients with the bullous form of ruber lichen planus in 14.3% of cases. In patients with pemphigus vulgaris, the association of Str.pneumoniae, C. albicans and EBV was noted in 31.6% of cases. In patients with the bullous form of ruber lichen planus in a high percentage of cases (28.6%), the associations of Str. pneumoniae, EBV and CMV. CONCLUSION: Identification at earlier stages of management of patients with bullous lesions Str. pneumoniae, Candida albicans, and Fusobacterium associated with herpes viruses should be regarded as one of the triggering mechanisms of an autoimmune conflict, which subsequently causes a specific clinical picture of these diseases.

The evaluation of the overexpression of the ERG-11, MDR-1, CDR-1, and CDR-2 genes in fluconazole-resistant Candida albicans isolated from Ahvazian cancer patients with oral candidiasis.

INTRODUCTION: Resistance to azole drugs has been observed in candidiasis due to their long-term use and poor response to treatment. Resistance to azole drugs in Candida albicans isolates is controlled by several genes including ERG11, CDR1, CDR2, and MDR1. In this study, the expression of the mentioned genes was evaluated in C. albicans isolates susceptible and resistant to fluconazole. METHODS: After identifying the Candida isolates using morphological and molecular methods, the minimum inhibitory concentration (MIC) and drug susceptibility were determined using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) method. RNA was then extracted and cDNA was synthesized from 24 C. albicans isolates from patients with cancer. Then, the mean expressions of these genes were compared in two groups using real-time polymerase chain reaction (RT-PCR). RESULTS: A total of 74 Candida isolates were obtained from the oral cavity of 61 cancer patients with oral candidiasis. After 24 h, 21.6% of the isolates were fluconazole-resistant, 10.8% were identified as dose-dependent, and the rest of the isolates (67.6%) were fluconazole-sensitive. The mean expressions of the CDR1 and MDR1 genes were significantly higher in the resistant isolates than in the sensitive ones. However, the ERG11 and CDR2 genes were not significantly increased in the resistant isolates. CONCLUSION: The increased mean expressions of the CDR1 and MDR1 genes had a greater effect on fluconazole resistance among the drug-resistant strains of C. albicans in chemotherapy patients. It seemed that the accumulation of chemotherapeutic drugs in this organism stimulated some regulatory factors and increased the expression of these two genes and ultimately helped to further increase their expression and resistance to fluconazole.

Rapid and sensitive recombinase polymerase amplification combined with lateral flow strips for detecting Candida albicans.

Owing to modern lifestyles and increasing amounts of medical intervention, clinical infections caused by conditionally pathogenic fungi are becoming increasingly serious. Among these, Candida albicans is the most common. Therefore, the rapid and accurate detection of this pathogenic fungus is important to guiding the selection of clinical therapeutic agents. Recombinase polymerase amplification (RPA) combined with lateral flow strips (LFS) is a promising molecular detection method with the advantages of rapidity, simplicity of operation and high sensitivity. However, this simplicity brings with it the inherent and non-negligible risk of false-positive signals from primer-dimers. In this study, primer-dependent artifacts were eliminated by using probes in the RPA reaction, introducing specific base substitutions to the primer and probe sequences and analyzing and screening the formation of primer-probe complexes. These measures were rigorously tested for efficacy, leading to the creation of an improved RPA-LFS system. The standardized method enabled the specific detection of C. albicans within 25 min at 37 °C without interference. The system had a detection limit of 1 CFU per reaction without DNA purification or 102 fg genomic DNA/50 µL. The detection sensitivity was not affected by the presence of other fungal DNA. The RPA-LFS method can therefore be used to detect clinical samples, and the results are accurate and consistent in comparison with those obtained using quantitative PCR. This study provides a paradigm for eliminating the risk of false-positive primer dimers in isothermal amplification assays and establishes a simple and easy method for the detection of C. albicans.

Efficacy of intravitreal povidone-iodine administration for the treatment of Candida albicans endophthalmitis in rabbits.

This study aimed to investigate the efficacy of intravitreal povidone-iodine (PI) administration for the treatment of Candida albicans endophthalmitis. Forty New Zealand white rabbits were divided into four groups (n = 10 per group). After the induction of endophthalmitis using Candida albicans, groups A, B, and C received single intravitreal injections of 0.035 mg voriconazole, 0.3 mg PI, and their combination, respectively. Rabbits that were administered sham injections were in group D as controls. Fundus photography, vitreous culture, electroretinography (ERG), and histologic examinations of the retina were conducted on day 7. The anterior chamber flare (grade 0 to 4), severity of iritis (grade 0 to 4), and vitreous opacity (grade 0 to 3) were scored. Candida albicans was cultured in the vitreous sample. On day 7, the vitreous opacities were found in all groups. Compared to that in group D, groups A, B, and C showed a lower score for flare (p < 0.001) and iritis (p < 0.001) and less fungal growth in the vitreous culture (n = 2, 1, 1, and 10 in groups A, B, C, and D, respectively; p < 0.001). Furthermore, ERG and histologic findings demonstrated less affected a- and b-waves and damaged retinal tissues in groups A, B, and C. However, these findings were not different among groups A, B, and C. PI significantly improved Candida albicans endophthalmitis, and the effect was comparable that of the voriconazole, although some vitreous opacities remained. No synergistic effect of the combination of PI and voriconazole was observed. Intravitreal PI may be useful to treat Candida albicans endophthalmitis.

Whole genome sequencing confirms Candida albicans and Candida parapsilosis microsatellite sporadic and persistent clones causing outbreaks of candidemia in neonates.

Whole genome sequencing has been extensively used to describe infection outbreaks, although with limited application on Candida albicans and Candida parapsilosis.We retrospectively studied all patients admitted to the neonatal care unit diagnosed with candidemia caused by C. albicans (n = 46) or C. parapsilosis (n = 31) between 2007 and 2010 (Period 1) and 2011 and 2014 (Period 2). All isolates were genotyped by microsatellite markers. A cluster was defined as a group of ≥ 2 patients infected by strains with identical genotypes. For the validation of microsatellite markers and outbreak investigation, phylogenetic analyses and whole genome pairwise strain comparisons were performed.The number of episodes was significantly higher in Period 1 than in Period 2 (51 vs 32; P = 0.003); the reduction in the number of cases coincided with the educational campaign for catheter care implementation in 2011. Overall, eight genotypes were clusters involving 29 patients. All C. albicans (n = 5) and C. parapsilosis (n = 3) clusters were found during Period 1 before the educational campaign. No statistically significant differences were found between the percentage of C. albicans and C. parapsilosis clusters, but the percentage of patients associated to the clusters was significantly higher for C. parapsilosis clusters in comparison to C. albicans clusters (52 vs 28.2%; P = 0.03). Whole genome sequencing confirmed microsatellite-defined clusters with high bootstrap values.Whole genome sequences confirmed microsatellite-defined clusters, corroborating the presence of outbreaks. Persistent or sporadic Candida clusters causing candidemia in neonates disappeared after the implementation of catheter care educational campaigns. LAY SUMMARY: We retrospectively studied all patients admitted to the neonatal care unit diagnosed with candidemia caused by C. albicans or C. parapsilosis. Reliable whole genome sequences confirmed microsatellite-defined clusters, corroborating the presence of outbreaks before educational campaigns for catheter care.

Pharmacokinetics of fluconazole and ganciclovir as combination antimicrobial chemotherapy on ECMO: a case report.

Extracorporeal membrane oxygenation (ECMO) can affect antimicrobial pharmacokinetics. This case report describes a 33-year-old male with newly diagnosed acquired immunodeficiency syndrome presenting in acute severe type 1 respiratory failure. On investigation, the patient had positive cultures for Candida albicans from respiratory specimens and high blood cytomegalovirus titres, and required venovenous ECMO therapy for refractory respiratory failure. Intravenous fluconazole (6 mg/kg, 24-h) and ganciclovir (5 mg/kg, 12-h) was commenced. Pre-oxygenator, post-oxygenator and arterial blood samples were collected after antibiotic administration, and were analysed for total fluconazole and ganciclovir concentrations. Although there was a 40% increase in the volume of distribution for fluconazole relative to healthy volunteers, the pharmacodynamic targets for prophylaxis were still met. The area under the curve exposure of ganciclovir (50.78 mg•h/L) achieved target thresholds. The ECMO circuit had no appreciable effect on achievement of therapeutic exposures of fluconazole and ganciclovir.