No abstract

This study demonstrates the ability of Candida albicans, a medically significant human fungal pathogen, to minimize contact with an antifungal surface coating that on a flat surface is lethal on contact by growing on and between micron-sized surface topographical features, thus minimizing the contact area. Scanning electron microscopy showed that cells contacting the “floor” between microcones were killed, whereas cells attached to microcones survived and formed hyphal filaments. These spanned space between cones and avoided contact with the flat surface in-between cones. Thus, fungal cells managed to attach and grow despite the antifungal coating. This ability of Candida albicans to exploit topography features to minimize surface contact yet utilize the solid surface for anchoring reduces the effectiveness of the grafted antifungal surface coating. This suggests that biomedical devices with rough surfaces might be more challenging to protect against fungal biofilm formation via application of an antifungal coating.

Objective: The aim of our study was to identify the distribution of Candida species among clinical isolates and their sensitivity pattern for common antifungal drugs.Methods: This descriptive study was carried out in a tertiary care hospital in Allahabad. A total of One hundred and four Candida isolates were included in the study. Identification and speciation of the isolates were carried out by Germ-tube test, Chlamydoconidia production test, colony characterization in chromogenic agar medium, carbohydrate assimilation test and growth at 45°C. Four antifungal drugs such as Fluconazole (25 mcg), Clotrimazole (10 mcg), Nystatin (100 U) and Amphotericin-B (100 U) were tested by disk diffusion method. Descriptive statistics was used which involves the use of simple percentage and bar chart to analyze the data. In addition, Chi-square test was performed and P value was calculated.Results: Out of 104 Candida isolates, 60 (58%) were from Urine, 36 (34.5%) were from Sputum and 8(7.5%) were from blood isolates. Of the total of 104 isolates 64 (61.5%) were Candida albicans, 20(19%) Candida dubliniensis, 10 (9%) Candida tropicalis, 7(6.5%) Candida parapsilosis and 4(4%) Candida glabrata respectively. Resistance rates for commonly use antifungal drugs among the isolates are as followed Fluconazole 76 (73%), Amphotericin B 40 (38.5%), Nystatin 4(4%) and Clotrimazole 60 (58%) respectively. For Candida albicans and Candida dubliniensis most active antifungal drug was Nystatin (93%; 100% respectively).Discussion: Species level identification of Candida and their antifungal sensitivity testing should be performed routinely in all microbiology laboratories to prevent the spread of antifungal resistance.