Josiara Furtado Mendes

Prevalence of Candida spp. in cervical-vaginal samples and the in vitro susceptibility of isolates.

Vulvovaginal candidiasis (VVC) is an infection of the genital mucosa caused by different species of the genus Candida. Considering the lack of data on this topic in the south of Brazil, this study aimed to assess the prevalence of Candida spp. in the cervical-vaginal mucosa of patients treated at a university hospital in southern Rio Grande do Sul, as well as the etiology and the susceptibility of the isolates against fluconazole, itraconazole, miconazole and nystatin. Samples were collected at the gynecology clinic of the Federal Hospital of the University of Rio Grande, and the isolates were identified using phenotypic and biochemical tests. The susceptibility analysis was performed according to the CLSI M27-A2 protocol. Of the 263 patients included, Candida spp. was isolated in 27%, corresponding to a prevalence of approximately 15% for both VVC and colonization. More than 60% of the isolates were identified as Candida albicans; C. non-albicans was isolated at a rate of 8.6% in symptomatic patients and 14.3% in asymptomatic patients. The prevalence of resistance against fluconazole and itraconazole was 42% and 48%, respectively; the minimal inhibitory concentration of miconazole ranged from 0.031 to 8 μg/mL, and that of nystatin ranged from 2 to >16 μg/mL. The high rate of resistance to triazoles observed in our study suggests the necessity of the association of laboratory exams to clinical diagnosis to minimize the practice of empirical treatments that can contribute to the development of resistance in the isolates.

FUNGI ISOLATED FROM THE EXCRETA OF WILD BIRDS IN SCREENING CENTERS IN PELOTAS, RS, BRAZIL

The identification of the fungal species belonging to the healthy microflora in animals is a precondition for the recognition of pathological processes causing them. The aim of this study was to investigate the presence of potentially pathogenic fungi in the feces of wild birds collected in Screening Centers. Samples were collected from the feces of 50 cages with different species of birds. The samples were processed according to the modified method STAIB and the plates incubated at 32 °C for up to ten days with daily observation for detection of fungal growth. The isolation of the following species was observed: Malassezia pachydermatis, Candida albicans, C. famata, C. guilliermondii, C. sphaerica, C. globosa, C. catenulata, C. ciferri, C. intermedia, Cryptococcus laurentii, Trichosporon asahii, Geotrichum klebahnii, Aspergillus spp., A. niger and Penicillium spp. Knowing the character of some opportunistic fungi is important in identifying them, facilitating the adoption of preventive measures, such as proper cleaning of cages, since the accumulation of excreta may indicate a risk for both health professionals and centers for screening public health.

Paracoccidioidomycosis infection in domestic and wild mammals by Paracoccidioides lutzii

Paracoccidioidomycosis (PCM) is a systemic mycosis that occurs in several Latin American countries, especially in Brazil. It is caused by the thermo‐dimorphic fungus Paracoccidioides spp. Serological studies to detect animal infection represent an excellent strategy for data on the agents ecology. Although the state of Rio Grande do Sul (RS) is an endemic area for PCM in humans, there is scarce information available on the ecology of the agent in the region. This study aimed to investigate the infection by Paracoccidioides lutzii in animals living in RS, Brazil. A total of 85 wild mammals, 200 horses and 196 domestic dogs, previously tested for infection by P. brasiliensis, were included in this study. Serum samples from the animals were tested by ELISA to detect anti‐ P. lutzii antibodies. From the 481 animals tested, 105 (21.8%) were seropositive for IgG anti‐P. lutzii. Of these, 54 were also positive for P. brasiliensis. A total of 11 horses (10.5%), 30 dogs (28.8%) and 10 wild mammals (9.5%) were positive only for P. lutzii (n=51). The detection of anti‐P. lutzii antibodies in animals of RS suggests that the fungus can be found in southern Brazil, despite being described mainly in the midwest and southeast of the country.

Antiparasitic drugs: in vitro tests against nematophagous fungi

The use of biological agents has been intensified in recent years against eggs and larvae of gastrointestinal nematodes as an alternative control method in pasture plant health management, with the concomitant use with antiparasitic drugs still occurring. The aim of this study was to test the in vitro activity of the following antiparasitic drugs: Ivermectin and albendazole against the following nematophagous fungi: Paecilomyces fumosoroseus, Paecilomyces lilacinus and Paecilomyces variotii. The agar diffusion test was performed using an initial concentration of 0.0016g/mL of each drug, after solidification of the culture medium containing the drug concentration each nematophagous fungi was inoculated. The results showed that in a concentration of 80μg/mL, the fungal growth decreased, however, with the concentration of 160μg/mL, there was no fungal growth in both drugs, compared to the control, which indicates an inhibition in the development of the nematophagous fungi studied when they come in contact with ivermectin and albendazole.

In vitro susceptibility of nematophagous fungi to antiparasitic drugs: interactions and implications for biological control

The fast anthelmintic resistance development has shown a limited efficiency in the control of animals endoparasitosis and has promoted research using alternative control methods. The use of chemicals in animal anthelmintic treatment, in association with nematophagous fungi used for biological control, is a strategy that has proven to be effective in reducing the nematode population density in farm animals. This study aims to verify the in vitro susceptibility of the nematophagous fungi Arthrobotrys oligospora, Duddingtonia flagrans and Paecilomyces lilacinus against the antiparasitic drugs albendazole, thiabendazole, ivermectin, levamisole and closantel by using the Minimum Inhibitory Concentration (MIC). MICs ranged between 4.0 and 0.031 µg/mL for albendazole, thiabendazole and ivermectin, between 0.937 and 0.117 µg/mL for levamisole, and between 0.625 and 0.034 µg/mL for closantel. The results showed that all antiparasitic drugs had an in vitro inhibitory effect on nematophagous fungi, which could compromise their action as agents of biological control. D. flagrans was the most susceptible species to all drugs.

Can Aspergillus fumigatus conidia cause false-positive results in the galactomannan enzyme immunoassay test?

INTRODUCTION Several factors can cause false-positive results in the galactomannan (GM) test; however, others remain unknown. Presently, the impact of airborne contamination by Aspergillus conidia during enzyme-linked immunosorbent assay (ELISA) remains uninvestigated. METHODS We studied 12 A. fumigatus isolates. Fungal conidia were serially diluted and tested for GM detection using the Platelia® Aspergillus enzyme immunoassay (EIA). RESULTS The conidia concentration required for an EIA-positive result was 4.8 × 103 (median). CONCLUSIONS This is the first study to evaluate the impact of environmental contamination on the Platelia® Aspergillus EIA assay. Only massive contamination can interfere with GM optical readings, suggesting that environmental contamination does not cause false-positive test results.

Evaluation of the frequency of Candida spp. in hospitalized and non-hospitalized subjects

The aim of this study was to evaluate the frequency of Candida species between a non-hospitalized and a hospitalized population. For this purpose, samples of saliva were sampled through sterile swabs, moistened in peptone water and rubbed in the oral cavity of 140 individuals, from which, 70 were hospitalized patients from the Medical Clinic of a Teaching Hospital and the other 70 were non-hospitalized subjects. All saliva samples were plated in Sabouraud Dextrose agar added with Chloramphenicol and incubated at 36 °C for 48 hours. The morphology identification was performed through macroscopic and microscopic characterization, the CHROMagar Candida medium and the VITEK® system Yeast Biochemical Card (bio Mérieux SA, France). The results showed a colonization of Candida spp. in 85.7% the hospitalized individuals, where the species found were C. albicans (60%), C. tropicalis (23.4%), C. krusei (3.3%) and Candida spp. (13.3%). In the non-hospitalized individuals the colonization by Candida spp was 47.1%, and the species found were: C. albicans (45.5%), C.krusei (9.1%), C. guilliermondii (9.1% %), C. tropicalis (3.0%), C. famata (3.0%) and Candida spp. (30.3%). In spite of their presence in oral cavity in both groups, Candida spp. was more frequently isolated in hospitalized individuals, who were 6.73 times more likely to have this fungus in the oral cavity and were 3.88 times more likely to have Candida albicans.

Applicability of the Platelia EIA® Aspergillus test for the diagnosis of aspergilosis in penguins

Even today, an effective diagnostic test for aspergillosis in penguins is unknown, being the gold standard post-mortem examinations. The fungal antigen galactomannan (GM) has been used as a biomarker of disease in humans and is detected by the Platelia Aspergillus EIA (BioRad)®, a commercial kit based on the sandwich ELISA technique. It is standardized for use in neutropenic patients, however studies have demonstrated its usefulness also possible for birds. The aim of our study was to evaluate the effectiveness of Platelia Aspergillus EIA® test (BioRad-US) in the diagnosis of aspergillosis in Magellanic penguins, determining sensitivity, specificity, and positive and negative predictive values for different cut-off points. Were included in the study, blood serum samples (n = 29) Magellanic penguins in captivity that died by aspergillosis. Detection of GM was performed following manufacturers instructions and the GM index was obtained by dividing the average value of OD of the duplicate of the clinical sample by duplicate OD of the average value of the cut-off sample provided by the kit. Through information database results were obtained for the presence of anti-Aspergillus fumigatus antibodies detected by agar gel immunodiffusion (AGID) for all serum samples. Results were analyzed using chi-square test and Kruskal-Wallis from SPSS 20.0, IBM®. ROC curve was obtained and from this, rates of sensitivity, specificity, positive and negative predictive values were also calculated based on four different cutoff points (0.5, 1.0, 1.5 and 2.0). The serum GM index did not differ between animals of the case and control group (pkw =0.097). In determining the ROC curve for serum GM detection the value of area under the curve was 0.635. From the values ​​determined by the coordinate of the curve, four different cut points (0.5, 1.0, 1.5 and 2.0) were analyzed, resulting in sensitivity rates ranging from 86.2 to 34.5% % and specificity between 87% and 26.1%. By comparing the serum GM index in group case as the presence or absence of antibodies detected by AGID was found p=0.503. The detection of GM the Platelia Aspergillus EIA® test seems is not be useful for the diagnosis of aspergillosis in naturally infected penguins.

Antifungal susceptibility profile of diferent yeasts isolates from wild animals, cow’s milk with subclinical mastitis and hospital environment

Yeast infections have acquired great importance due to increasing frequency in immunocompromised patients or patients undergoing invasive diagnostic and therapeutic techniques, and also because of its high morbidity and mortality. At the same time, it has been seen an increase in the emergence of new pathogenic species difficult to diagnose and treat. The aim of this study was to determine the in vitro susceptibility of 89 yeasts from different sources against the antifungals amphotericin B, voriconazole, fluconazole and flucytosine, using the VITEK® 2 Compact system. The antifungal susceptibility was performed automatically by the Vitek® 2 Compact system. The origin of the yeasts was: Group 1 - microbiota of wild animals (W) (26/89), 2 - cows milk with subclinical mastitis (M) (27/89) and 3 - hospital enviorment (H) (36/89). Of the 89 yeasts submitted to the Vitek® 2 test, 25 (20.9%) were resistant to fluconazole, 11 (12.36%) to amphotericin B, 3 (3.37%) to voriconazole, and no sample was resistant to flucytosine. Regarding the minimum inhibitory concentration (MIC), fluconazole showed an MIC between 1 and 64 mg/mL for the three groups, voriconazole had an MIC between 0.12 and 8 mg/mL, amphotericin B had an MIC between 0.25 and 4 mg/mL for group H and group W respectively, between 0.25 and 16 mg/mL for group M and flucytosine had an MIC equal to 1μg/mL for all groups. The yeasts isolated from the H group showed the highest resistance to fluconazole 12/89 (13.49%), followed by group W (7.87%) and group M (5.62%). The more resistant group to voriconazole was followed by the M and H groups, the W group showed no resistance to this antifungal. Group H was the least resistant (2.25%) to amphotericin.

Airborne fungi in an intensive care unit

The presence of airborne fungi in Intensive Care Unit (ICUs) is associated with increased nosocomial infections. The aim of this study was the isolation and identification of airborne fungi presented in an ICU from the University Hospital of Pelotas - RS, with the attempt to know the places environmental microbiota. 40 Petri plates with Sabouraud Dextrose Agar were exposed to an environment of an ICU, where samples were collected in strategic places during morning and afternoon periods for ten days. Seven fungi genera were identified: Penicillium spp. (15.18%), genus with the higher frequency, followed by Aspergillus spp., Cladosporium spp., Fusarium spp., Paecelomyces spp., Curvularia spp., Alternaria spp., Zygomycetes and sterile mycelium. The most predominant fungi genus were Aspergillus spp. (13.92%) in the morning and Cladosporium spp. (13.92%) in the afternoon. Due to their involvement in different diseases, the identified fungi genera can be classified as potential pathogens of inpatients. These results reinforce the need of monitoring the environmental microorganisms with high frequency and efficiently in health institutions.