Molecular detection of Paracoccidioides in soil from an urban area of southern Brazil

Abstract INTRODUCTION: Previous studies that detected Paracoccidioides spp. DNA in soil taken from rural areas have shown this to be a valuable tool for ecological and epidemiological studies. This study reports the detection of Paracoccidioides spp. DNA in soil samples from an urban area of southern Brazil. METHODS: Sixteen soil samples were submitted to nested-PCR and the amplicons of a representative number of positive samples were sequenced. RESULTS: Paracoccidioides spp. DNA was found in 44% of samples. Four DNA amplicons were sequenced, showing 100% homology with P. brasiliensis. CONCLUSIONS: The southern Brazilian urban population is commonly exposed to the Paracoccidioides fungus.

Paracoccidioides spp. in Soil from the Pampa Biome in Southern Brazil.

High rates of paracoccidioidomycosis disease and infection have been recently reported in southern Brazil. However, the knowledgment about the ecoepidemiology of Paracoccidioides spp. in the region is limited, therefore, this study aimed to evaluate the presence of Paracoccidioides spp. DNA in soil samples from a rural area in Southern Rio Grande do Sul, Brazil. Thirty pools of soil samples from Bagé, RS (31º19'53"S 54º06'25"W) were submitted to physicochemical analysis, and to fungal DNA extraction by Norgen Biotek® Kit (Thorold, Canada), followed by Nested PCR technique with ITS4 and ITS5 as external primers, and PBITS-E and PBITS-T as internal primers. DNA amplification products of about 424 bp compatible with Paracoccidioides spp. were detected in eight (26.7%) of the 30 pools of samples, being three were sequenced and identified as P. brasiliensis. Positive soils were characterized by high levels of humidity, organic matter, basic saturation, and pH. This study shows for the first time the presence of Paracoccidioides spp. DNA at soils from the Brazilian Pampa Biome, proving that people living in those areas are exposed to the main agent of paracoccidioidomycosis.

Antifungal activity of diphenyl diselenide alone and in combination with itraconazole against Sporothrix brasiliensis.

Sporothrix brasiliensis is the main agent of feline and zoonotic sporotrichosis. Given the scarcity of options for sporotrichosis treatment and the promising activity of diphenyl diselenide (PhSe)2 against a diversity of fungal pathogens, this study aimed to evaluate the in vitro susceptibility of Sporothrix brasiliensis to (PhSe)2 alone and in combination with itraconazole (ITC). Forty clinical isolates of S. brasiliensis were subjected to broth microdilution method to evaluate their susceptibility to (PhSe)2 in concentrations ranging between 0.25 and 128 µg/ml, and to ITC (0.0313-16 µg/ml) following the protocol of the Clinical and Laboratory Standards Institute (CLSI, 2008). All of these isolates were also used to evaluate the interaction between these drugs by checkerboard technique. Geometric mean of (PhSe)2 MIC values was 12.12 µg/ml, ranging from 4 to 32 µg/ml, and for ITC was 0.37 µg/ml (0.125 to 1 µg/ml). Benefic effect (additive or synergistic) in the interaction test between (PhSe)2 and ITC occurs in 73% (29/40) of the isolates. The promising (PhSe)2in vitro activity against S. brasiliensis suggests that it may not only be a potential alternative therapy but also be used as a combination with ITC, which is the first choice of therapy to sporotrichosis.

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.

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

Abstract 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.

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

Abstract 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.

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 8µg/mL, and that of nystatin ranged from 2 to >16µg/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 rrom the excreta of wild birds in screening centers in pelotas, rs, Brazil / Fungos isolados de excretas de aves silvestres em centro de reabilitação em Pelotas, RS, Brasil

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.

A identificação das espécies de fungos pertencentes à microbiota saudável em animais é pré-condição para o reconhecimento dos processos patológicos causados por esses. O objetivo deste estudo foi investigar a presença de fungos potencialmente patogênicos nas fezes de aves selvagens coletadas em Centros de Triagem. Foram coletadas amostras de fezes de 50 gaiolas com diferentes espécies de aves. As amostras foram processadas de acordo com o método modificado STAIB e as placas foram incubadas a 32 °C por até dez dias, com observações diárias para detecção do crescimento dos fungos. Observamos o isolamento de espécies: 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 e Penicillium spp. Conhecendo o caráter de alguns fungos oportunistas resalta-se a importância para identificá-los, facilitando a adoção de medidas preventivas, como a limpeza adequada das gaiolas, uma vez que a acumulação de excrementos pode indicar um risco tanto para os profissionais de saúde e centros de triagem de saúde pública.

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.