CHROMagar Candida Research Articles

Prevalence and susceptibility profiles of oral yeast species isolated from a healthy adult Thai cohort

ObjectiveAs the emerging resistance of Candida species to common antifungals is a major global concern, we assessed the antifungal susceptibility of oral yeast isolates from a healthy, Thai adult cohort, and correlated the yeast prevalence with oral disease indices. MethodsOral rinse samples collected from 100 Thai adults were concentrated and cultured on CHROMagar Candida. The yeasts were then isolated, identified and finally speciated using Matrix Assisted Laser Desorption ionization-time of flight mass spectrometry. Their antifungal sensitivity against fluconazole, itraconazole, voriconazole, and amphotericin B were investigated using standard Etest strips. The decayed, missing, filled teeth (DMFT) and the periodontal health were recorded and correlated with mycological data. ResultsThe overall oral yeast prevalence was 25%. C. albicans was the commonest species isolated, followed by C. tropicalis and C. dubliniensis. Non-albicans-Candida was noted in approximately one-third, and included C. lusitaniae and C. nivariensis; Trichosporon asahii, was also detected in one subject. A majority of C. albicans isolates, (> 54%), exhibited resistance to fluconazole and voriconazole, while approximately a quarter (27%) were resistant to itraconazole. The vast majority (92%) however, were susceptible to amphotericin B. Those with oral yeasts had a significantly higher DMFT score (p < 0.05). ConclusionThe resistance of a majority of Candida spp. to common azoles, described here for the first time in a Thai cohort, is disconcerting, and appear to confirm the creeping emergence of antifungal resistance globally. An incidental finding was the positive correlation between oral yeast carriage and DMFT score in Thai subjects.

Ketoconazole: A Re-emerging choice for Oral candidiasis in patients with human immunodeficiency virus infection/acquired Immunodeficiency Syndrome

Background: The long term use of antifungals for oral candidiasis (OC) in patients with Human Immunodeficiency Virus (HIV) and Acquired Immune Deficiency Syndrome (AIDS) causes some strains to be resistant to certain antifungals. HIV/AIDS are currently most common in men. Aim: To evaluate ketoconazole sensitivity on Candida species in male HIV/AIDS patients with OC. Method: This is an observational descriptive study at the Outpatient Unit and Inpatient Installation of the Infectious Disease Intermediate Care Unit (UPIPI) Dr. Soetomo, Surabaya. Samples were taken from HIV/AIDS male patients with OC using sterile swabs. The smear was cultured in CHROMagar Candida incubated at 37°C for 48-72 hours, and Sabouraud Dextrose Agar media for 48 hours at 28°C. Species identification were done using carbohydrate and Cornmeal test. Resistance test was done by disk diffusion method. Results: There were 23 research subjects with 40 isolates of Candida species growing in culture. The most common species was C. albicans in 23(57.5%) isolates, while Candida non-albicans were found in 17(42.5%) isolates. The sensitivity test results showed that 34 (85%) isolates were sensitive, while 2(5%) isolates were resistant to ketoconazole. All C. albicans (23 [100%]) and most Candida non-albicans species (11 [64%]) were sensitive to ketoconazole. Conclusion: Ketoconazole can be recommended as a treatment option for OC patients with HIV/AIDS due to the high sensitivity of both C. albicans and non-albicans to this drug.

In Vitro evaluation of antimycotic activity of oregano essential oil on candida species from isolation of patient with chronic periodontitis

Background: Candida albicans is an opportunistic fungi mainly causing mucosal and opportunistic infections in immunocompromised people. Origanum vulgare is an herbal plant that has been used as a food flavouring agent in many countries . It has strong antiseptic and antimicrobial activity due to the presence of carvacrol and thymol, which directly inhibit germination and hyphal formation in candida. Periodontitis is one of the first diseases to be related to mixed-species biofilms in humans. C. albicans produces virulence factors that may play a role in the incidence of periodontal disease, such as penetrating ability, colonisation and growth of candida species in the oral mucosa and periodontal pocket. AIM: Is to evaluate the antimycotic activity of oregano essential oil on candida species isolated from patient with chronic periodontitis Materials And Methods: The study was conducted at Saveetha dental college .Ethical clearance for the study was obtained from the Institutional Ethical Committee. Swabs were obtained from the subgingival plaque tooth surface of patients who had clinical symptoms of chronic periodontitis. For the isolation of Candida from the clinical samples, the obtained samples were plated onto candida chromagar. The isolated species of candida is then investigated for antimycotic activity. The antimycotic activity of oregano essential oil on Candida species isolates was examined using an agar well diffusion assay. Result And Discussion : Antimycotic activity of the Oregano essential oil against clinical isolates of Candida albicans are shown in the table. The findings reveal that oregano essential oils showed a zone of inhibition of 21 mm against Candida albicans at concentration of 100μL compared to the standard ketoconazole which shows a zone of inhibition of 25 mm. As the concentration of the extract increases the zone of inhibition increases . Conclusion: Based on the results presented , it is possible to conclude that the essential oil extracted from Oregano may represent a good alternative for the treatment of candidiasis due to its appreciable antifungal action against Candida spp in vitro.

Medically important Candida spp. identification: an era beyond traditional methods.

Candida infections are gaining more attention for the last few decades so diagnostic tools are very important for early diagnosis. Conventional identification of yeasts is time-consuming, molecular methods are more complicated and relatively expensive gold-standard methods. Matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) was put into the market due to its speed and high accuracy. The aim of this study was to evaluate the performance of corn meal tween-80 agar (CMTA), CHROMagar Candida medium, and MALDI-TOF MS and to compare the obtained results with DNA sequencing. The CHROMagar Candida medium, CMTA, and MALDI-TOF MS Biotyper System were used to test 416 isolates. The isolates with discrepant results by at least one of the three methods were subjected to sequence analysis. The identification results of the 351 (%84.4) were compatible with all three methods. When compared to the sequencing results, the most accurate results were obtained by the MALDI-TOF MS, especially for rare Candida species. MALDI-TOF MS is found to be the most accurate identification tool for clinically important Candida strains. CMTA alone should not be used for the final identification of Candida species and the chromogenic medium should always be considered presumptive.

DNA SEQUENCING OF NOVEL YEAST ISOLATED FROM BLOODSTREAM INFECTIONS IN AL-NAJAF PROVINCE.

The aim: To identify of fungal isolates using PCR techniques with universal primer (ITS1-ITS4 and ITS3-ITS4). A total of 533 blood samples from cancer patients, renal failure patients and patients who underwent cardiac catheterization have been included in this study. Materials and methods: Devices and tools were used to preceding the study as shown in table (I), while biological and chemical materials are given in table (II). Results: Three groups, 44 isolates of Candida spp were isolated: 35(79.6%) isolates from cancer patients, 6(13.6%) isolates from patients with renal failure, and 3 (6.8%) isolates from patients with cardiac catheterization. These yeasts were diagnosed by conventional methods and by CHROMagar Candida medium, as well as by molecular methods to detect the regions of ITS2, ITS1, and the isolates were diagnosed as belonging to the yeast Candida spp. These isolates were also diagnosed using DNA sequencing detection technology and 12 new strains were recorded for the first time In the name of the researcher by the Japan Gene Bank. Conclusions: It was concluded that there was high susceptibility of the polymerase chain reaction technique based on ITS 1, ITS2 primers in diagnosing the types of yeasts isolated from the bloodstream with high accuracy and speed compared to other traditional methods. Therefore, the DNA sequencing method is considered one of the best rapid standard methods for the diagnosis of fungi.

Recovery of Candida spp. from a denture rat model

Denture stomatitis is a common infection in denture wearers. This study evaluated the recovery of Candida spp. from the palate of Wistar rats after using an acrylic device with single and mixed-species of Candida spp. After approval of the Ethics Committee, 84 male and female Wistar rats were used. Custom-made acrylic devices were fabricated for each animal and sterilized by microwave irradiation. Single and mixed species biofilms of C. albicans (Ca), C. glabrata (Cg), and C. tropicalis (Ct) were grown on the devices for 48 h at 37°C. Rats were anesthetized and the devices were cemented on the molar teeth (n=5 for each sex and Candida spp.). Rats received a carbohydrate-rich diet. Single and mixed species were inoculated in the oral cavity thrice after three-day intervals. Controls received only dentures without Candida spp. After 4 weeks, the devices were removed, the palates were swabbed, and diluted samples were plated on Agar Sabouraud Dextrose and CHROMAgar Candida for colony counting and presumptive identification, respectively, after 48 h. Data were analyzed by 3way ANOVA (α=5%). There was a significant interaction (p=0.003) between sex and species. For females, all groups recovered significant values (p≤0.027) compared with controls. For males, groups with Ct as single and dual-species showed the lowest values without difference (p≥0.183) with the control. The groups with triple-species showed the highest values but without difference (p≥0.071) with the groups with single and dual-species, except males with Ct. Ct alone showed reduced recovery from palate of male rats.

715. Evaluation of Four Chromogenic Selective Media for the Isolation of Candida auris

Abstract Background Candida auris is an emerging healthcare-associated multi-drug resistant pathogen able to cause severe invasive infections. Public health agencies have emphasized the need for active surveillance of C. auris to enable prompt infection control measures in healthcare institutions. Four commercially available chromogenic selective media were evaluated for the isolation of C. auris in this study. Methods Four chromogenic selective media (Brilliance Candida (BC), CHROMagar Candida (CC), CHROMagar Candida Plus (CCP) and chromID Candida (CAN2)) were evaluated with 52 fungal and 20 bacterial strains. Isolates were identified with Vitek matrix-assisted laser desorption/ionization mass spectrometry (MS). 1 µL spots of broth subcultures of each organism were inoculated onto chromogenic media and incubated as per manufacturer’s instructions. Plates were read at 24, 36 and 48 hours. Sabouraud Dextrose agar (fungi) or blood agar (bacteria) were inoculated to obtain viable counts. All reads were categorized into color groups. Sensitivity and specificity were determined based on phenotypic characteristics after 48h of incubation. Additionally, spots of serially diluted C. auris type strain CDC B11903 were assessed for expression of the expected C. auris phenotype at 36, 48 and 72 h. Probit regression model (R version 3.6.3) was used to estimate limit of detection (LOD) for each medium at each time-point. Results A minimum of 36h incubation (optimally &amp;gt; 48 h) was required for observation of distinct color and colony morphology. CCP performed best overall, with 100% sensitivity and 96% specificity. Sensitivity was 100% across all 4 media, but specificity was reduced (BC – 66%, CAN2 – 83%, CC – 81%). The lowest LOD was observed with CCP at 4 colony-forming units (CFU). See figure 1 for details. Figure 1. Comparison of limit of detection for C. auris by type of chromogenic selective media across various time-points. Conclusion Rapid isolation and accurate identification of C. auris from samples, including those from non-sterile sites, are crucial for the management of C. auris infections and in curtailing nosocomial transmission. Chromogenic media are simple to use, inexpensive and scalable; ideal for routine diagnostics and high volume screening samples. Of the 4 media evaluated, CCP is best suited to screen for C. auris, with subsequent confirmation of identification using MS or genotypic methods. Disclosures Lynette Phee, MD PhD, Creative Life Science Co. Ltd (Creative Media Plate) (Other Financial or Material Support, Provided some of the CHROMagar Candida and CHROMagar Candida Plus plates free-of-charge for evaluation purposes.)Fort Richard Laboratories (Other Financial or Material Support, Provided some of the CHROMagar Candida Plus plates free-of-charge for evaluation purposes.)

ASSESSMENT OF AIRBORNE FUNGAL SPORES IN INDOOR ENVIRONMENT OF LIBRARIES IN NNAMDI AZIKIWE UNIVERSITY

Background: Polluted indoor environments pose health challenges such as allergy, infections, and toxicity. Most indoor air pollution comes from hazardous non-biological and biological agents. Due to the nature of the indoor environment of libraries, it is prone to colonization by fungal species. Method: Three sampling sites were used for the study and they include Festus Aghagbo Nwako Library, Main campus Awka, Medical Library, Nnewi Campus and Library Complex, Agulu campus. A total of 100 air samples were analyzed Using the Zefon A6 Single-stage microbial air sampler and Malt Extract Agar supplemented with 0.05mg/ml of chloramphenicol while 16 nasal swabs were collected from the staff present using sterile swab sticks. The mould isolates were identified using the slide culture technique while the yeast isolates were subjected to candida chrom agar and integral yeast plus identification. Antifungal susceptibility was performed using the integral yeast plus system and the agar well diffusion technique. Results: Out of the 100 air samples, a total of 625 fungal isolates were identified of which C.lunata 201 (32.16%) was the most predominant, while P. marneffi, P. expansum, A. restrictus, A. infectoria and R. rubra 1(0.16%) occurred the least. All significant at (p≤0.01). A total of 7 fungal spores were isolated from the 16 nasal swabs and appeared thus in descending order of frequency: P. notatum, 3 (42.85%), A. niger, C. lunata, C. albicans and F. aqueductum, 1(14.3%). Antifungal Susceptibility of the 28 yeast isolates indicated that C. famata, C. laurentii and C. luteolus, were all susceptible to commonly used antifungals in the integral yeast plus system with a 100% susceptibility value, while the mould isolates showed relatively moderate susceptibility to selected antifungals. Conclusion: The organisms isolated are well known to be pathogenic especially to immunocompromised individuals. Their presence in the indoor environment of libraries serves as a risk factor to both the library staff and visitors. Adequate precautionary measures and occasional environmental surveillance need to be inculcated in order to reduce the number of fungi in the indoor environment of these libraries.

Speciation of candida species isolated in clinical samples in a tertiary health care centre in Northern India

The purpose of this study is to isolate, identify and specification of various the Candida species from various clinical samples in a tertiary care hospital, and to characterize various the isolated Candida species. A study was conducted on people of different age groups from January 2019 to December 2019. Candida species isolated from different patients by using Potassium Hydroxide mount and processed by BacTalert 3D (Biomerieux) automated blood culture system. Further culture identification of Candida species were done on Sabouraud dextrose agar (SDA). Speciation of Candida was done using Germ tube test, CHROM agar Candida Medium, Cornmeal agar, Sugar Fermentation test and Sugar Assimilation test.In our study was the most common species isolated, among non albicans Candida i.e. 21 (38.9%); 19(35.2%) of was the most common followed by 9(16.7%) ofand 5(9.3%) of . Maximum number of Candida isolates were obtained from NICU i.e. 27(50.0%) followed by 11 from Med (20.3%), 7 from E/W (13.0%), 2 from BICU (3.7%), 2 from Skin (3.7%), 1 from PICU (1.9%), and 1 from R/R (1.9%).Our study showed that is the most common isolates species. Among , was found to be the most common isolate followed by . Children less than 1 year are most affected with maximum number of Candida species were obtained from NICU department. HiChrom Candida is proven to be more useful as differential agar.

Detection of Salmonella, Shigella and Candida spp. in stool from diarrheal children and evaluation the heating effect on Salmonella phage in Kirkuk city

Background: Salmonella spp. and Shigella are two pathogenic members within the Enterobacteriaceae family, and they are causing food poisoning and diarrhea that transmits via oral route by contaminated food and water especially in children from ages 1 day to 14 years.&#x0D; Objective: focus on the study of Salmonella spp., Shigella and Candida spp. isolated from diarrheal children in Kirkuk city and diagnose via in vitro bacterial diagnosis with traditional fermentation chemical tests, API 20E, RapIDTM ONE technology and Vitek 2 compact system, as well as study the thermal stability of isolated Salmonella phage,&#x0D; Method: Collecting (200) cases of diarrhea from children in Kirkuk hospitals, through an epidemiological statistical study and conventional methods for diagnosis enteric bacteria with API 20E and RapIDTM ONE, and non-typhi Salmonella isolates (S.typhimurium) were identified with Vitek 2 compact System. Bacterial sensitivity tests to antibiotics were verified by Kerby - Bauer disk diffusion method and Candida spp. with CHROM agar Candida and API 20C AUX ; The Salmonella phage was isolated by spot assay, then exposed to different temperatures before the observation of degradation range of the exposed phage to the salmonella non-typhi, on Tryptic Soy Agar medium (TSA).&#x0D; Results: Salmonella spp., Shigella and E. coli isolated in rate of 6%, 0.5% and 51.5% respectively while intestinal candida detected in rate of 89.5% in total of 200 children were diagnosed, in which 113 samples of males (56.5%) and 87 samples of females (43.5%) (p&gt; 0.05), the degradation range was observed to the exposed phage to degrees (35, 40) C. for (15, 30) minutes, and stopped at the exposed Salmonella phages to temperatures (45) at 30 minutes.&#x0D; Conclusion: The prevalence of salmonella and shigella was relatively low and the highest incidence of Salmonella was within the age groups ranging between (11-14) and (1-6) year compared to other age groups. Isolated strains showed multidrug resistance (MDR), As well the genus Candida albicans was the most common type compared to other intestinal Candida species in children with diarrhea. and it has been found that salmonella phage can be isolated from sewage water and chicken's droppings by simple methods.

Violet colonies of Talaromyces marneffei produce on CHROMagar candida medium

In the present report, we describe an unusual case of mixed infection of Candida albicans and Talaromyces marneffei in the oral cavity and oropharynx with cutaneous involvement. On the CHROMagar Candida plate, green colonies (identified as C. albicans) and tiny violet colonies (identified as T. marneffei) grew from the throat swab after incubation for 96 hours. 10 clinical isolates of T. marneffei were used to verify their color production on CHROMagar Candida. All colonies were violet on the fourth, seventh and ninth day incubated at 37 °C. T. marneffei appears violet on the CHROMagar Candida plate, but it may be easily ignored because of its slow growth and small colony size, especially after incubation for 48 hours. Therefore, when using CHROMagar Candida plate to detect specimens in AIDS patients, special attention must be paid to detect non–yeasts such as T. marneffei for up to 96 hours.

CORRELATE BETWEEN BIOFILM FORMATION AND AZOLE ANTIFUNGAL SUSCEPTIBILITY AGAINST PLANKTONIC AND SESSILE CANDIDA ALBICANS CLINICAL ISOLATES

Objective: To assess the correlation between biofilm formation and azole antifungal susceptibility against plank tonic and sessile clinical isolates of C.albicans.&#x0D; Study Design: Prospective observational study.&#x0D; Place and Duration of Study: Combined Military Hospital Peshawar, from Jun 2016 to Sep 2017.&#x0D; Methodology: All standard microbiological procedures were carried out according to latest Clinical &amp; laboratory standard institute (CLSI) guidelines. After gram staining and presumptive identification on CHRO Magar Candida, the isolates were biochemically identified by API AUX Candida as C.albicans. Planktonic antifungal susceptibility was carried out by Kirby Bauer disk diffusion method on 300 C.albicans isolates. Broth microdilution method was used to determine Minimum inhibitory concentration (MICs) of plank tonic cells and micro titer assay was used for assessment of biofilm formation by C.albicans.&#x0D; Results: In planktonic antifungal susceptibility, fluconazole was susceptible against 195 (65%) and voriconazole against 241 (80%) C. albicans isolates. C. albicans was found susceptible dose dependent (SDD) to fluconazole in 28 (9%) and to voriconazole in 21 (7%) isolates. Seventy-seven (26%) and 38 (13%) C.albicans isolates were found fluconazole and voriconazole resistant, respectively. Sessile antifungal susceptibility was carried out through broth micro dilution method in which 160 (53%) were susceptible, 42 (14%) were susceptible dose dependent SDD and 98 (33%) were resistance to voriconazole, and 161 (54%) were susceptible, 36 (12%) were SDD and 103 (34%) were found resistant to fluconazole. Biofilm forming isolates of C.albicans were observed to be 285 (95%).The p-value is highly significance i.e. &lt;0.01 between......

Factors influencing the presence of Candida dubliniensis and other non-albicans species in patients with oral lichen planus: a retrospective observational study

ObjectivesThe epidemiologic distribution of non-albicans species in the oral cavity of oral lichen planus (OLP) patients remains uncertain. Therefore, the aim of this study was to identify factors associated with the presence of C. dubliniensis and other non-albicans species. Furthermore, independent risk factors for Candida superinfection in OLP should be identified.Material and methodsEpidemiologic data and microbiological findings from 268 symptomatic OLP patients who underwent continuous oral swab culture over a 5-year period (2015–2019) were retrospectively reviewed. Candida species identification and semi-quantification were obtained by culture on CHROMagar Candida, followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).ResultsC. albicans was the most frequently isolated species (72.3%), followed by C. glabrata (7.3%), C. dubliniensis (5.8%), C. krusei and C. parapsilosis (both 2.6%). The presence of C. dubliniensis was significantly associated with tobacco smoking. Other non-albicans spp. were significantly more often detected in patients using removable dentures. Increasing age and the intake of psychotropic drugs were identified as independent risk factors of Candida superinfection in OLP.ConclusionIn OLP patients, certain local and systemic factors increase the risk of carrying potentially drug-resistant Candida species and the development of Candida superinfection of OLP lesions.Clinical relevanceDue to the frequent detection of non-albicans species in OLP, resistance or at least reduced sensitivity to azole antifungals should be expected, especially in smokers and patients using removable dentures. In the case of oral complaints, a superinfection with Candida should be considered, whereby older patients and patients taking psychotropic drugs have an increased risk for oral infection with Candida.

MICROEVOLUTION OF CANDIDA ALBICANS STRAINS IN OLDER PEOPLE WITH LOW SALIVARY FLOW

Background Populations are aging worldwide, and older people are more likely to take medications and undergo treatment leading to side effects such as salivary gland hypofunction. It is not known how reduced salivary flow in older people affects the Candida albicans strains colonizing the oral cavity. The presence of resistant Candida strains could be debilitating for immunocompromised older people. Objective The aim of this study was to compare C. albicans strains colonizing the mouths of older people with low and normal salivary flow. Methods Participants aged 65 and above (n = 50) were examined, and their salivary flow rates (SFRs) were determined. Swabs and smears of the palate and tongue and saliva samples were collected. Smear products were stained with periodic acid-Schiff (PAS). Yeasts were cultured, quantified, and presumptively identified using CHROMagar Candida agar. Multilocus sequence typing was used to compare C. albicans strains. Results Twenty-four participants had a low SFR ( 400 CFU/mL saliva) (68% vs 38%), presented with more PAS-positive smears (47% vs 19%), and had more C. albicans strains with evidence of microevolution (8 of 12 participants vs 1 of 5 participants) than those with normal salivary flow. Conclusions Increased yeast presence in older people with low salivary flow was confirmed. There was a link between SFR and microevolution of C. albicans. The genetic changes may be because C. albicans is under pressure to adapt to a low-saliva environment.

Virulence Factors and Antifungal Susceptibility Profile of C. tropicalis Isolated from Various Clinical Specimens in Alexandria, Egypt

Background: The incidence of candidiasis caused by non-albicans Candida (NAC) species is increasing. Candida tropicalis has emerged as one of the most important NAC species. This study aims to examine the antifungal susceptibility profile and some virulence factors of C. tropicalis isolated from various clinical specimens. Methods: A total of 71 C. tropicalis isolates from various clinical specimens (69.01%, 18.31%, 9.86%, and 2.82% of isolates were collected from urine, respiratory samples, blood, and skin and soft tissue infections, respectively) from ICU patients in Alexandria, Egypt. The isolates were identified at species level by CHROMagar Candida and VITEK 2 compact system. Furthermore, the antifungal susceptibility was determined using the VITEK 2 system AST-YS07 card containing different antifungals. Hemolysin, phospholipase, and proteinase activity and biofilm formation were also tested as virulence factors. Results: Only 30 isolates (42.25%) were non-susceptible (MIC ≥ 4 µg/mL) to fluconazole, of which 28 isolates showed non-susceptibility (MIC ≥ 0.25 µg/mL) to voriconazole. All isolates showed both hemolysin and proteinase activities, while only 9 isolates (12.68%) showed phospholipase production and 70 isolates (98.59%) demonstrated biofilm formation. Strong biofilm production was observed among the blood culture isolates (85.71%), followed by the respiratory and urinary isolates (61.54% and 46.94%, respectively). Conclusions: This study sought to provide useful data on the antifungal susceptibility of C. tropicalis isolates from ICU patients suffering from invasive infections with an increased trend towards elevated MICs levels of both fluconazole and voriconazole. Due to the high incidence of systemic candidiasis and antifungal resistance, C. tropicalis is emerging as a serious root of infections. Therefore, early and accurate identification of Candida species along with susceptibility testing is of utmost importance.

Association between Antimicrobial Peptide Histatin 5 Levels and Prevalence of Candida in Saliva of Patients with Down Syndrome.

There are no studies on Candida colonization and micropeptides of saliva in any patient. Therefore, we studied the effects of the salivary antimicrobial peptide histatin 5 on oral fungal colonization; subjects were subdivided into Down syndrome (D) and normal (N) groups by age: N-1 and D-1, age <20 years; N-2 and D-2, age >40 years. Histatin 5 concentration in saliva was measured by enzyme-linked immunosorbent assay. Oral Candida species were identified using CHROMagar Candida. Candida colonization was significantly enhanced in the D-1 and D-2 groups compared to the N-1 and N-2 groups. There was no predominant difference in salivary histatin 5 concentration between the D-1 and N-1 groups, but it was significantly lower in the D-2 group than in the N-2 group. Only in the N-2 group was there a correlation between the concentration of histatin 5 and total protein, while no correlation was found in the other groups. In elderly patients with Down syndrome, the decrease in histatin 5 shown in this study may lead to oral Candida colony formation. Therefore, the results of this study suggest that a deficiency of the antimicrobial peptide histatin 5 could possibly induce oral Candida infection in DS.

Antimicrobial resistance among fungi from patients with urinary tract infections in Ojo, Lagos, Nigeria

The incidence of fungal urinary tract infections has risen gradually and has thus constituted a public health challenge. The aim of this study was to determine the prevalence of urinary tract infections by fungi in two health centres in Ojo, Lagos. A total of 200 patients attending the health centers constituting 160 males’ urines and 40 females’ vaginal swabs were recruited for this study. Midstream urine samples and vaginal swabs were aseptically collected and processed using standard mycological techniques. Fungal isolates were identified based on cultural characteristics, lactophenol blue stain, chlamydospore formation, colony colour on CHROM agar Candida medium and API yeast identification. Antifungal susceptibility testing of the isolates was performed by using the Broth dilution and Kirby-Bauer disk diffusion methods using two of the most commonly used antifungal agents. A total of 122 fungal isolates, of which 68 (55.7%) were Candida spp. and 54(44.3%) Aspergillus spp. were recovered. The Candida spp. included 64 (52.5%) C. albicans and 4(3.3%) C. glabrata while Aspergillus spp. included A. flavus, 20(16.4%), A. fumigatus, 24 (19.8%) and A niger, 10(8.2%). The most common fungal pathogens in the urinary tracts of the subjects were Candida albicans and Aspergillus fumigatus. Both C. albicans and A. fumigatus were highly susceptible to both fluconazole and amphotericin B in dimethyl sulphoxide and water (90-100%). Similarly, all Aspergillus spp. were susceptible to both antifungals except A. flavus which showed a slight resistance (10-15%), which appears to be emerging. Both fluconazole and amphotericin B still show high chances of therapeutic efficacy against fungal infections of the urinary tracts.

Candida tropicalis distribution and drug resistance is correlated with ERG11 and UPC2 expression

BackgroundCandida tropicalis (C. tropicalis) is an important opportunistic pathogenic Candida species that can cause nosocomial infection. In this study, we analyzed the distribution and drug susceptibility of C. tropicalis and the relationship between ERG11 and UPC2 expression and resistance to azole antifungal agents.MethodsC. tropicalis was cultured and identified by Sabouraud Agar Medium, CHROM Agar Candida and ATB tests (Bio-Mérieux, France). Total RNA was extracted from the collected strains, and the ERG11 and UPC2 mRNA expression levels were analyzed by quantitative real-time PCR.ResultsIn total, 2872 clinical isolates of Candida, including 319 strains of C. tropicalis, were analyzed herein; they were mainly obtained from the Departments of Respiratory Medicine and ICU. The strains were predominantly isolated from airway secretion samples, and the detection trend in four years was mainly related to the type of department and specimens. The resistance rates of C. tropicalis to fluconazole, itraconazole and voriconazole had been increasing year by year. The mRNA expression levels of ERG11 and UPC2 in the fluconazole-resistant group were significantly higher than they were in the susceptible group. In addition, there was a significant positive linear correlation between these two genes in the fluconazole-resistant group.ConclusionsOverexpression of the ERG11 and UPC2 genes in C. tropicalis could increase resistance to azole antifungal drugs. The routine testing for ERG11 and UPC2 in high-risk patients in key departments would provide a theoretical basis for the rational application of azole antifungal drugs.

The Use of MALDI-TOF Mass Spectrometry to Analyze Commensal Oral Yeasts in Nursing Home Residents

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate method to identify microorganisms in clinical laboratories. This study isolates yeast-like microorganisms in the oral washes that are collected from non-bedridden nursing home residents, using CHROMagar Candida plates, and identifies them using Bruker MALDI-TOF MS. The ribosomal DNA sequences of the isolates are then examined. Three hundred and twenty yeast isolates are isolated from the oral washes. Candida species form the majority (78.1%), followed by Trichosporon/Cutaneotrichosporon species (8.8%). Bruker MALDI-TOF MS gives a high-level confidence, with a log(score) value of ≥1.8, and identifies 96.9% of the isolates. There are six inconclusive results (1.9%), and those sequences are verified as rare clinical species, including Candida ethanolica, Cutaneotrichosporon jirovecii, Exophiala dermatitidis, and Fereydounia khargensis. Almost all of the isolates have a regular color on the CHROMagar Candida plates. If the colonies are grouped by color on the plates, a specific dominant yeast species is present in each color group, except for purple or orange isolates. In conclusion, MALDI-TOF MS is verified as a fast, accurate and practical method to analyze oral yeasts in elderly subjects.

High prevalence of asymptomatic nosocomial candiduria due to Candida glabrata among hospitalized patients with heart failure: a matter of some concern?

Background and Purpose: Heart failure is a leading cause of hospitalization, and asymptomatic candiduria is common in hospitalized patients with low morbidity. However, in most patients, it is resolved spontaneously on the removal of the catheter. Despite the publication of guidelines, there are still controversies over the diagnosis and management of candiduria. However, in hospitalized patients with heart failure, the decision to treat candiduria is especially important since the nosocomial infections are associated with an increase in morbidity, mortality, length of hospital stay, and healthcare costs. Some species of Candida, such as Candida glabrata, are increasingly resistant to the first-line and second-line antifungal medications. The present study aimed to investigate the incidence of asymptomatic Candida urinary tract infection due to C. glabrata and antifungal susceptibility of Candida isolates in hospitalized patients with heart failure.Materials and Methods: In total, 305 hospitalized patients with heart failure were studied to identify asymptomatic nosocomial candiduria during 2016-17 in one private hospital in the north of Iran. The Sabouraud’s dextrose agar culture plates with a colony count of >104 colony-forming unit/ml of urine sample were considered as Candida urinary tract infection. Candida species were identified based on the morphology of CHROMagar Candida (manufactured by CHROMagar, France) and PCR-RFLP method with MspI restriction enzyme. Antifungal susceptibility testing of the isolates was performed using five mediations, including itraconazole, voriconazole, fluconazole, amphotericin B, and caspofungin by broth microdilution method according to CLSI M27-S4.Results: In this study, the rate of asymptomatic Candida urinary tract infection was 18.8%, which was more common in people above 51 years old and females (70%). In addition to the urinary and intravascular catheter, the occurrence of candiduria in hospitalized patients had significant relationships with a history of surgical intervention, diastolic heart failure, and use of systemic antibiotics (P>0.05). Among Candida spp., non-albicans Candida species was the most common infectious agent (59.7%). Moreover, C. glabrata (n=27, 40.3%) (alone or with other species) and Candida albicans (n=27, 40.3%) were the most common agents isolated in Candida urinary tract infection. Based on the results of the in vitro susceptibility test, the C. glabrata isolates were 15%, 59%, 70%, 74%, and 85% susceptible to caspofungin, amphotericin B, itraconazole, voriconazole, and fluconazole, respectively.Conclusion: According to the findings, there was a high prevalence of asymptomatic Candida urinary tract infection in hospitalized patients with heart failure. Besides, it was suggested that there was a shift towards non-albicans Candida, especially C. glabrata, in these patients. Therefore, asymptomatic candiduria in hospitalized patients with heart failure should be considered significant. Furthermore, the identification of Candida species along with antifungal susceptibility is essential and helps the clinicians to select the appropriate antifungal agent for better management of such cases.