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Objectives: This study was performed to provide epidemiological information on microbial colonization in central venous catheters (CVCs)., Methods: CVCs submitted to Medical Microbiology Laboratory from January 1, 2013, through October 1, 2017, which met our criteria would be included for analysis. Quantitative culture was used for CVCs. The results of culture and related information on CVCs were collected and recorded in detail. The prevalence was calculated, and related factors were analyzed statistically., Results: A total of 2020 CVCs were submitted for culture and eligible for analysis. Positive microbial culture occurred in 379 catheters with 18.7% (379 of 2020) prevalence of colonization. There were 23 microbial genera and 45 organisms detected. Among the isolated organisms, there were 39 kinds of isolated bacteria and 6 kinds of isolated fungi. Acinetobacter (19.8%) predominated in total isolated microorganisms, followed by Staphylococcus epidermidis (11.3%) and Candida albicans (10.3%). There were no significant differences in isolated organisms and fungal species between different sexes ( X 2  = 2.365, P = 0.50). Conversely, there were significant differences in isolated bacterial and fungal species between different wards and years ( X 2  = 124.046, P = 0.000; X 2  = 77.064, P = 0.000). A total of 107 (5.3%, 107/2020) CVCs were associated with a diagnosis of central line-associated bloodstream infection (CLABSI). The most common organisms in causing CLABSI were Acinetobacter (23.4%), S. aureus (13.1%), and Candida albicans (12.1%)., Conclusion: The prevalence of microbial colonization in CVCs is still significant and even has gradually changed over time. The study provides a new view of microbial colonization pattern in CVCs and a prevalence of CLABSI, which will facilitate catheter-related infection prevention and control in clinic., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2019 Yu He et al.)

This study aimed to establish the influence of biofilm from clinical isolates of Candida albicans on fluconazole resistance, focusing on efflux pumps and azole-targeted enzymes. Twenty-three C. albicans clinical isolates were collected from two hospitals in Shanghai, China. Antifungal susceptibility tests were performed on biofilm and planktonic cells. A crystal violet assay was used to monitor biofilm growth. Real-time RT-PCR was performed to quantify the expression of the transporter-related genes MDR1, CDR1, and CDR2 as well as ERG11, a gene encoding an enzyme targeted by antifungal drugs. Fluconazole resistance was shown to increase in biofilm in a time-dependent manner. No significant differences were observed between different strains of C. albicans. Genes encoding efflux pumps were overexpressed in early stages of biofilm formation and could also be induced by fluconazole. While ERG11 was not upregulated in biofilm, it was overexpressed upon the addition of fluconazole to biofilm and planktonic cells. Gene expression also appeared to be related to the original genotype of the strain. The upregulation of genes encoding efflux pumps demonstrates their role in the development of fluconazole resistance during the early stages of C. albicans biofilm formation.

Candida albicans, as an opportunistic pathogen, can cause superficial and life-threatening candidiasis in immunocompromised individuals. The formation of surface-associated biofilms and the appearance of drug resistance pose a significant challenge for clinical intervention. In this study, a total of 104 hospital-acquired C. alibcans clinical isolates were collected from sterile sites and mucosal lesions of 92 infectious disease patients in the Shanghai Public Health Clinical Center and analysed. The resistance rates to fluconazole, itraconazole and voriconazole were 12.5 %, 15.4 % and 11.5 % respectively. Multilocus sequence typing (MLST) analysis identified 63 diploid sequence types (DSTs) with a decentralized phylogeny, of which 37 DSTs (58.7 %) had not been reported in the online MLST database. Loss of heterozygosity was observed in ACC1 and ADP1 sequences obtained from six sequential isolates from a patient receiving antifungal treatment, which exemplified the effect of microevolution on C. albicans genetic alterations. Biofilm formation capability, an important virulence trait of C. albicans, was variable among strains isolated from different anatomical sites (P = 0.0302) and affected by genotypes (P = 0.0185). The mRNA levels of the azole antifungal target ERG11 gene and efflux pump genes (CDR1, CDR2 and MDR1) were detected in 9-18.1 % of azole-resistant and susceptible-dose dependent (S-DD) isolates. Twelve mutations encoding distinct amino acid substitutions in ERG11 were found in azole-resistant and S-DD isolates. Among them, A114S, Y132H and Y257H substitution in the ERG11 gene may be primarily related to azole resistance. Taken together, we observed a high level of diversity within C. albicans isolates. Multiple inter-related underlying mechanisms, including genetic and environmental factors, may account for high surface adhesion or azole resistance in clinical C. albicans infections., (© 2015 The Authors.)

Objectives: To investigate the incidence rates of candidemia in hospitalized patients and to identify differences in risk factors of patients with Candida albicans and non-C. albicans and with Candida guilliermondii and non-C. guilliermondii candidemia., Methods: Non-immunosuppressed, non-neutropenic inpatients with candidemia diagnosed after admission were included in this retrospective observational study at a tertiary academic hospital in China., Results: During the study period (January 2009 to December 2011), 238 eligible patients had candidemia episodes with an incidence rate 5.4%. Of these patients, 29.8% had candidemia due to C. albicans, 27.7% due to C. parapsilosis, and 16.4% due to C. guilliermondii. Diabetes was a significant risk factor for patients with candidemia due to C. albicans (35.2%, 25/71) compared to candidemia due to non-C. albicans spp (13.2%, 22/167) (odds ratio (OR) 0.2792, 95% confidence interval (CI) 0.144-0.5412; p < 0.001). Compared to patients with candidemia due to non-C. guilliermondii spp, preterm birth with low birth weight (OR 0.0887, 95% CI 0.0398-0.1977; p < 0.001), intravenous nutrition (OR 0.0662, 95% CI 0.0226-0.1938), and surgery (OR 0.0662, 95% CI 0.0226-0.1938; p < 0.001) were significant risk factors for candidemia due to C. guilliermondii. Furthermore, compared to patients with candidemia due to C. albicans, patients with candidemia due to C. guilliermondii had markedly higher rates of central venous catheterization (85.9%, 61/71 vs. C. guilliermondii: 100%, 39/39; p = 0.013) and intravenous nutrition (89.7%, 35/39 vs. C. albicans: 42.2%, 30/71; p < 0.001)., Conclusions: Candidemia due to C. albicans ranks first in incidence, and candidemia due to C. guilliermondii occurs in a significant proportion of our hospitalized patients., (Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The objectives of this study are to investigate the carriage rate of Candida albicans from the patients with oral lichen planus (OLP, erosive and non-erosive subtypes) and the healthy control individuals in a Chinese cohort and then to compare the virulence attributes of these isolates. Oral C. albicans isolates from 300 patients with OLP as well as 128 healthy controls were isolated and a total of 112 isolates from patients with erosive OLP (62), non-erosive OLP (24) and healthy control (26) were screened for phospholipase activity by using an in vitro plate assay method. Adhesion ability of the above isolates was also studied by using buccal epithelial cells assay. Statistically, the carriage rate of C. albicans from the patients with erosive OLP (44.29%) was higher than that of patients with non-erosive OLP (15.00%) or the healthy control group (20.31%) (P < 0.001). The adhesion to buccal epithelial cells of the isolates from the erosive OLP group (3.950 +/- 1.436) was more marked (P < 0.001) than that from healthy control (2.2112 +/- 0.4833). The phospholipase activity of these isolates either from erosive (0.4170 +/- 0.029) or non-erosive OLP groups (0.4327 +/- 0.028) was higher (P < 0.001) than that from healthy controls (0.5259 +/- 0.074). Some C. albicans isolates with special virulence attributes might be co-factors, which contribute to the development of OLP, especially erosive OLP.