Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as... more Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as opportunistic pathogens in animals. Malassezia pachydermatis is commonly isolated from the ear canal and skin of healthy dogs, or in association with seborrheic dermatitis and otitis externa conditions. The objective of the present study was to determine the occurrence of Malassezia spp. in the ears of healthy bovines and bovines with otitis. Specimens (secretion or cerumen) were collected with sterile swabs, inoculated onto Mycosel medium, supplemented with olive oil, and incubated at 35 °C for 1 week. Yeasts were identified according to morphological characteristics, growth in Dixon medium at 32 °C and Sabouraud glucose medium modified by the addition of Tween 20, 40 or 80. The results showed that 54·7% of the cultures were positive in bovines with otitis (75) and 34·6% were positive in healthy bovines (378). Analysis of the positive cultures (41) from animals with otitis allowed presumptive identification of 24 strains corresponding to M. globosa (12), M. slooffiae (5), M. furfur (5) and M. sympodialis (2). Further studies on a larger number of animals may confirm the trend verified thus far, i.e. a higher frequency of isolation of Malassezia spp. from animals with otitis than from healthy animals (P≪0·01) and a predominance of the species M. globosa.
Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, we... more Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, were used to evaluate the epidemiology of Malassezia species. High numbers of Malassezia isolates were significantly associated with maturity of the animals and with diagnosed otitis. In healthy animals, a particularly low prevalence of the genus was found in Holstein cows, especially in the summer months, a finding perhaps correlating with the open, air-exposed ears of this breed. Pendutlous-eared zebu breeds and hybrids had higher levels of colonization, although this effect was more pronounced in humid regions, and was least in the dry north and west of the state. The most common species seen was M. sympodialis, which accounted for 47.1% of isolates from healthy cattle and 39.1% from cattle with otitis. In cattle with otitis sampled in summer, we found that the relatively thermotolerant M. sympodialis made up 80.8% of isolates. By contrast, during the winter the less thermotolerant M. globosa was the most common species from otitis, making up 56% of the isolates. Humidity and temperature may be the main factors explaining the epidemiology of Malassezia diseases and colonizations in both animals and humans.
Revista Da Sociedade Brasileira De Medicina Tropical, 2009
Thirty-seven isolates from 10 HIV-negative and 26 HIV-positive patients in Mato Grosso were evalu... more Thirty-seven isolates from 10 HIV-negative and 26 HIV-positive patients in Mato Grosso were evaluated. Direct examination, culturing and chemotyping of species were performed. Ketoconazole, itraconazole, voriconazole, fluconazole and amphotericin B were evaluated. Thirty-seven yeasts of Cryptococcus spp were identified, of which 26 were from HIV-positive patients (25 Cryptococcus neoformans and one Cryptococcus gattii) and 10 from HIV-negative patients (five Cryptococcus neoformans and five Cryptococcus gattii). The Cryptococcus neoformans clinical isolates from HIV-positive patients showed resistance (8% and 8.7%) and dose-dependent susceptibility (20% and 17.4%) to fluconazole and itraconazole, respectively. Among the Cryptococcus neoformans isolates from HIV-negative patients, there was dose-dependent susceptibility (40%) to fluconazole. Cryptococcus gattii isolates from HIV-negative patients were shown to be susceptible to all antifungal agents, except for one isolate of Cryptococcus gattii that showed dose-dependent susceptibility to fluconazole (20%). The Cryptococcus gattii isolate from an HIV-positive patient showed resistance to fluconazole (MIC > 256 ¼g/ml) and itraconazole (MIC = 3 ¼g/ml).
Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as... more Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as opportunistic pathogens in animals. Malassezia pachydermatis is commonly isolated from the ear canal and skin of healthy dogs, or in association with seborrheic dermatitis and otitis externa conditions. The objective of the present study was to determine the occurrence of Malassezia spp. in the ears of healthy bovines and bovines with otitis. Specimens (secretion or cerumen) were collected with sterile swabs, inoculated onto Mycosel medium, supplemented with olive oil, and incubated at 35 degrees C for 1 week. Yeasts were identified according to morphological characteristics, growth in Dixon medium at 32 degrees C and Sabouraud glucose medium modified by the addition of Tween 20, 40 or 80. The results showed that 54.7% of the cultures were positive in bovines with otitis (75) and 34.6% were positive in healthy bovines (378). Analysis of the positive cultures (41) from animals with otitis allowed presumptive identification of 24 strains corresponding to M. globosa (12), M. slooffiae (5), M. furfur (5) and M. sympodialis (2). Further studies on a larger number of animals may confirm the trend verified thus far, i.e. a higher frequency of isolation of Malassezia spp. from animals with otitis than from healthy animals (P<0.01) and a predominance of the species M. globosa.
Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, we... more Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, were used to evaluate the epidemiology of Malassezia species. High numbers of Malassezia isolates were significantly associated with maturity of the animals and with diagnosed otitis. In healthy animals, a particularly low prevalence of the genus was found in Holstein cows, especially in the summer months, a finding perhaps correlating with the open, air-exposed ears of this breed. Pendutlous-eared zebu breeds and hybrids had higher levels of colonization, although this effect was more pronounced in humid regions, and was least in the dry north and west of the state. The most common species seen was M. sympodialis, which accounted for 47.1% of isolates from healthy cattle and 39.1% from cattle with otitis. In cattle with otitis sampled in summer, we found that the relatively thermotolerant M. sympodialis made up 80.8% of isolates. By contrast, during the winter the less thermotolerant M. globosa was the most common species from otitis, making up 56% of the isolates. Humidity and temperature may be the main factors explaining the epidemiology of Malassezia diseases and colonizations in both animals and humans.
Revista Da Sociedade Brasileira De Medicina Tropical, 2009
Between 2005 and 2008, the prevalence of systemic mycosis among 1,300 HIV/AIDS patients in Cuiabá... more Between 2005 and 2008, the prevalence of systemic mycosis among 1,300 HIV/AIDS patients in Cuiabá, Mato Grosso, was 4.6%. The fungus species isolated were Cryptococcus neoformans in 50%, Cryptococcus gattii in 1.6%, Cryptococcus spp in 6.6%, Histoplasma capsulatum in 38.3% and Paracoccidioides brasiliensis in 3.3%. Death was recorded in the cases of 32 patients (53.3%), and cryptococcosis was the main cause. The CD4+ T lymphocyte count was low and similar among patients who survived or died due to systemic mycosis. The factors independently associated with the deaths of these patients were alcoholism (OR: 8.2; 95% CI: 1.4-62.1; p = 0005) and the mean level of lactate dehydrogenase [758 (182) U/l vs. 416 (268) U/l; p < 0001]. The findings showed that systemic mycosis was highly lethal among the patients with HIV/AIDS in Cuiabá and suggested that clinical-laboratory characteristics such as alcoholism and early elevation of lactate dehydrogenase may be factors relating to worse prognosis under these conditions.
This study is the first report on genetic differences between isolates of Paracoccidioides brasil... more This study is the first report on genetic differences between isolates of Paracoccidioides brasiliensis from a single patient. We describe a simultaneous infection with genetically distinct isolates of P. brasiliensis in a patient with chronic paracoccidioidomycosis. The clinical isolates were obtained from lesions in different anatomical sites and were characterised by random amplified polymorphic DNA (RAPD) analysis. The RAPD technique can be helpful for distinguishing between clinical isolates. Different random primers were used to characterise these clinical isolates. The RAPD patterns allowed for differentiation between isolates and the construction of a phenetic tree, which showed more than 28% genetic variability in this fungal species, opening new possibilities for clinical studies of P. brasiliensis. Based on these results and preliminary clinical findings, we suggest that different genotypes of P. brasiliensis might infect the same patient, inducing the active form of the disease.
In this study, exoantigens produced from two Paracoccidioides brasiliensis strains isolated in tw... more In this study, exoantigens produced from two Paracoccidioides brasiliensis strains isolated in two different geographical areas were compared in terms of sensitivity and specificity in relation to paracoccidioidomycosis (PCM) diagnosis. Exoantigens from P. brasiliensis 550B (Ag 550B) isolated in the central-west region of Brazil (Mato Grosso State) and exoantigen produced from P. brasiliensis B-339 (Ag B-339) used in reference laboratories were compared by immunodiffusion (ID) tests. When Ag 550B was used in ID test against sera of patients from Mato Grosso and São Paulo, positivity was 92.3% and 41.3%, respectively. On the other hand, when Ag B-339 was tested with the same sera, positivity was 26.2% and 100%, respectively. These results suggest that differences in the antigenic composition probably related to phylogenetic peculiarities in P. brasiliensis isolates from the central-western region of Brazil should be considered in the diagnosis of PCM.
Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as... more Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as opportunistic pathogens in animals. Malassezia pachydermatis is commonly isolated from the ear canal and skin of healthy dogs, or in association with seborrheic dermatitis and otitis externa conditions. The objective of the present study was to determine the occurrence of Malassezia spp. in the ears of healthy bovines and bovines with otitis. Specimens (secretion or cerumen) were collected with sterile swabs, inoculated onto Mycosel medium, supplemented with olive oil, and incubated at 35 °C for 1 week. Yeasts were identified according to morphological characteristics, growth in Dixon medium at 32 °C and Sabouraud glucose medium modified by the addition of Tween 20, 40 or 80. The results showed that 54·7% of the cultures were positive in bovines with otitis (75) and 34·6% were positive in healthy bovines (378). Analysis of the positive cultures (41) from animals with otitis allowed presumptive identification of 24 strains corresponding to M. globosa (12), M. slooffiae (5), M. furfur (5) and M. sympodialis (2). Further studies on a larger number of animals may confirm the trend verified thus far, i.e. a higher frequency of isolation of Malassezia spp. from animals with otitis than from healthy animals (P≪0·01) and a predominance of the species M. globosa.
Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, we... more Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, were used to evaluate the epidemiology of Malassezia species. High numbers of Malassezia isolates were significantly associated with maturity of the animals and with diagnosed otitis. In healthy animals, a particularly low prevalence of the genus was found in Holstein cows, especially in the summer months, a finding perhaps correlating with the open, air-exposed ears of this breed. Pendutlous-eared zebu breeds and hybrids had higher levels of colonization, although this effect was more pronounced in humid regions, and was least in the dry north and west of the state. The most common species seen was M. sympodialis, which accounted for 47.1% of isolates from healthy cattle and 39.1% from cattle with otitis. In cattle with otitis sampled in summer, we found that the relatively thermotolerant M. sympodialis made up 80.8% of isolates. By contrast, during the winter the less thermotolerant M. globosa was the most common species from otitis, making up 56% of the isolates. Humidity and temperature may be the main factors explaining the epidemiology of Malassezia diseases and colonizations in both animals and humans.
Revista Da Sociedade Brasileira De Medicina Tropical, 2009
Thirty-seven isolates from 10 HIV-negative and 26 HIV-positive patients in Mato Grosso were evalu... more Thirty-seven isolates from 10 HIV-negative and 26 HIV-positive patients in Mato Grosso were evaluated. Direct examination, culturing and chemotyping of species were performed. Ketoconazole, itraconazole, voriconazole, fluconazole and amphotericin B were evaluated. Thirty-seven yeasts of Cryptococcus spp were identified, of which 26 were from HIV-positive patients (25 Cryptococcus neoformans and one Cryptococcus gattii) and 10 from HIV-negative patients (five Cryptococcus neoformans and five Cryptococcus gattii). The Cryptococcus neoformans clinical isolates from HIV-positive patients showed resistance (8% and 8.7%) and dose-dependent susceptibility (20% and 17.4%) to fluconazole and itraconazole, respectively. Among the Cryptococcus neoformans isolates from HIV-negative patients, there was dose-dependent susceptibility (40%) to fluconazole. Cryptococcus gattii isolates from HIV-negative patients were shown to be susceptible to all antifungal agents, except for one isolate of Cryptococcus gattii that showed dose-dependent susceptibility to fluconazole (20%). The Cryptococcus gattii isolate from an HIV-positive patient showed resistance to fluconazole (MIC > 256 ¼g/ml) and itraconazole (MIC = 3 ¼g/ml).
Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as... more Yeasts of the genus Malassezia are lipophilic microorganisms that are saprophytes that can act as opportunistic pathogens in animals. Malassezia pachydermatis is commonly isolated from the ear canal and skin of healthy dogs, or in association with seborrheic dermatitis and otitis externa conditions. The objective of the present study was to determine the occurrence of Malassezia spp. in the ears of healthy bovines and bovines with otitis. Specimens (secretion or cerumen) were collected with sterile swabs, inoculated onto Mycosel medium, supplemented with olive oil, and incubated at 35 degrees C for 1 week. Yeasts were identified according to morphological characteristics, growth in Dixon medium at 32 degrees C and Sabouraud glucose medium modified by the addition of Tween 20, 40 or 80. The results showed that 54.7% of the cultures were positive in bovines with otitis (75) and 34.6% were positive in healthy bovines (378). Analysis of the positive cultures (41) from animals with otitis allowed presumptive identification of 24 strains corresponding to M. globosa (12), M. slooffiae (5), M. furfur (5) and M. sympodialis (2). Further studies on a larger number of animals may confirm the trend verified thus far, i.e. a higher frequency of isolation of Malassezia spp. from animals with otitis than from healthy animals (P&amp;amp;lt;0.01) and a predominance of the species M. globosa.
Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, we... more Swabs collected from the external ears of 942 cattle, including both European and zebu breeds, were used to evaluate the epidemiology of Malassezia species. High numbers of Malassezia isolates were significantly associated with maturity of the animals and with diagnosed otitis. In healthy animals, a particularly low prevalence of the genus was found in Holstein cows, especially in the summer months, a finding perhaps correlating with the open, air-exposed ears of this breed. Pendutlous-eared zebu breeds and hybrids had higher levels of colonization, although this effect was more pronounced in humid regions, and was least in the dry north and west of the state. The most common species seen was M. sympodialis, which accounted for 47.1% of isolates from healthy cattle and 39.1% from cattle with otitis. In cattle with otitis sampled in summer, we found that the relatively thermotolerant M. sympodialis made up 80.8% of isolates. By contrast, during the winter the less thermotolerant M. globosa was the most common species from otitis, making up 56% of the isolates. Humidity and temperature may be the main factors explaining the epidemiology of Malassezia diseases and colonizations in both animals and humans.
Revista Da Sociedade Brasileira De Medicina Tropical, 2009
Between 2005 and 2008, the prevalence of systemic mycosis among 1,300 HIV/AIDS patients in Cuiabá... more Between 2005 and 2008, the prevalence of systemic mycosis among 1,300 HIV/AIDS patients in Cuiabá, Mato Grosso, was 4.6%. The fungus species isolated were Cryptococcus neoformans in 50%, Cryptococcus gattii in 1.6%, Cryptococcus spp in 6.6%, Histoplasma capsulatum in 38.3% and Paracoccidioides brasiliensis in 3.3%. Death was recorded in the cases of 32 patients (53.3%), and cryptococcosis was the main cause. The CD4+ T lymphocyte count was low and similar among patients who survived or died due to systemic mycosis. The factors independently associated with the deaths of these patients were alcoholism (OR: 8.2; 95% CI: 1.4-62.1; p = 0005) and the mean level of lactate dehydrogenase [758 (182) U/l vs. 416 (268) U/l; p < 0001]. The findings showed that systemic mycosis was highly lethal among the patients with HIV/AIDS in Cuiabá and suggested that clinical-laboratory characteristics such as alcoholism and early elevation of lactate dehydrogenase may be factors relating to worse prognosis under these conditions.
This study is the first report on genetic differences between isolates of Paracoccidioides brasil... more This study is the first report on genetic differences between isolates of Paracoccidioides brasiliensis from a single patient. We describe a simultaneous infection with genetically distinct isolates of P. brasiliensis in a patient with chronic paracoccidioidomycosis. The clinical isolates were obtained from lesions in different anatomical sites and were characterised by random amplified polymorphic DNA (RAPD) analysis. The RAPD technique can be helpful for distinguishing between clinical isolates. Different random primers were used to characterise these clinical isolates. The RAPD patterns allowed for differentiation between isolates and the construction of a phenetic tree, which showed more than 28% genetic variability in this fungal species, opening new possibilities for clinical studies of P. brasiliensis. Based on these results and preliminary clinical findings, we suggest that different genotypes of P. brasiliensis might infect the same patient, inducing the active form of the disease.
In this study, exoantigens produced from two Paracoccidioides brasiliensis strains isolated in tw... more In this study, exoantigens produced from two Paracoccidioides brasiliensis strains isolated in two different geographical areas were compared in terms of sensitivity and specificity in relation to paracoccidioidomycosis (PCM) diagnosis. Exoantigens from P. brasiliensis 550B (Ag 550B) isolated in the central-west region of Brazil (Mato Grosso State) and exoantigen produced from P. brasiliensis B-339 (Ag B-339) used in reference laboratories were compared by immunodiffusion (ID) tests. When Ag 550B was used in ID test against sera of patients from Mato Grosso and São Paulo, positivity was 92.3% and 41.3%, respectively. On the other hand, when Ag B-339 was tested with the same sera, positivity was 26.2% and 100%, respectively. These results suggest that differences in the antigenic composition probably related to phylogenetic peculiarities in P. brasiliensis isolates from the central-western region of Brazil should be considered in the diagnosis of PCM.
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