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Mycopathologia Apr 2023Malassezia pachydermatis is part of the normal skin microbiota of various animal species but under certain circumstances becomes an opportunistic pathogen producing...
Malassezia pachydermatis is part of the normal skin microbiota of various animal species but under certain circumstances becomes an opportunistic pathogen producing otitis and dermatitis. Commonly these Malassezia diseases are effectively treated using azoles. However, some cases of treatment failure have been reported. Alterations in the ERG11 gene have been associated with in vitro azole resistance in M. pachydermatis. In the present study, in vitro antifungal susceptibility of 89 different strains of M. pachydermatis isolated from different animal species and health status was studied. The susceptibility to fluconazole (FLZ), itraconazole (ITZ), ketoconazole and amphotericin B was tested by a disk diffusion method and 17 strains were also subjected to an ITZ E-test. Mueller-Hinton supplemented with 2% glucose and methylene blue was used as culture medium in both susceptibility assays. Multilocus sequence typing was performed in 30 selected strains using D1D2, ITS, CHS2 and β-tubulin genes. Also, ERG11 gene was sequenced. The four antifungals tested were highly effective against most of the strains. Only two strains showed no inhibition zone to antifungals and a strain showed an increased MIC to ITZ. The study of the ERG11 sequences revealed a high diversity of DNA sequences and a total of 23 amino acid substitutions, from which only two have been previously described. Also, three deleterious substitutions (A302T, G459D and G461D) previously associated with azole resistance in this yeast were recovered. A correlation between certain genotypes and ERG11 mutations was observed. Some of the ERG11 mutations recovered were correlated with a reduced susceptibility to azoles.
Topics: Animals; Antifungal Agents; Azoles; Malassezia; Ketoconazole; Itraconazole; Microbial Sensitivity Tests; Drug Resistance, Fungal
PubMed: 36495417
DOI: 10.1007/s11046-022-00696-9 -
Case Reports in Infectious Diseases 2022Invasive disease due to infection is uncommon but increasingly recognized in children, especially neonates on parenteral nutrition or immunocompromised children. We...
Invasive disease due to infection is uncommon but increasingly recognized in children, especially neonates on parenteral nutrition or immunocompromised children. We describe a case of fungemia in a demographically distinct patient and discuss the workup and current strategies for managing this infection in the setting of a central venous catheter.
PubMed: 35096432
DOI: 10.1155/2022/8636582 -
The New England Journal of Medicine Jul 1998
Topics: Animals; Dog Diseases; Dogs; Humans; Malassezia; Mycoses; Zoonoses
PubMed: 9687255
DOI: No ID Found -
Open Veterinary Journal 2022External otitis is common in dogs, and one of the main agents involved is , a yeast belonging to the otic microbiota. Empirical treatment can fail; therefore, it is...
BACKGROUND
External otitis is common in dogs, and one of the main agents involved is , a yeast belonging to the otic microbiota. Empirical treatment can fail; therefore, it is essential to know the antifungal susceptibility profile to prescribe appropriate treatment, a fact scarcely reported in Chile.
AIM
This study aimed to determine the antifungal sensitivity of isolated from the external auditory canal of dogs in central Chile.
METHODS
Ear swabs from 30 dogs (15 healthy and 15 with external otitis) were used. Samples were subjected to cytology and fungal culture. The antifungal susceptibility was determined according to clinical and laboratory standards institute (CLSI) document M44A-2 using the disk diffusion test from amphotericin B, Caspofungin, fluconazole, nystatin, clotrimazole, and voriconazole were used.
RESULTS
The prevalence of was 66.7% from 8 healthy dogs and 12 with otitis. While fungal culture was not associated with the patient's clinical condition ( = 0.24), the yeast count by cytology was significantly higher in dogs with otitis ( = 0.003). The strains were sensitive to all antifungals except for Caspofungin, where 55% of the strains were resistant.
CONCLUSION
is isolated more frequently in dogs with otitis, and the ear cytological examination is useful to differentiate colonized dogs versus dogs with otitis. In addition, most antifungals are active against this yeast, except Caspofungin, an antifungal used in human medicine. This situation should be further monitored in epidemiological programs to evaluate the possible impact on Chilean public health.
Topics: Animals; Antifungal Agents; Caspofungin; Chile; Dermatomycoses; Dog Diseases; Dogs; Malassezia; Otitis Externa; Saccharomyces cerevisiae
PubMed: 35342729
DOI: 10.5455/OVJ.2022.v12.i1.12 -
Mycoses 1991Five strains of Malassezia pachydermatis isolated from small animals in Bratislava were subcultured, maintained under sterile paraffin oil and preserved in liquid...
Five strains of Malassezia pachydermatis isolated from small animals in Bratislava were subcultured, maintained under sterile paraffin oil and preserved in liquid nitrogen. Morphological and physiological characteristics as well as the analysis of long chain fatty acids of the cell mass were determined. The results showed that the maintenance in liquid nitrogen is the most satisfactory method of preservation of pure cultures of Malassezia pachydermatis.
Topics: Animals; Cat Diseases; Cats; Dog Diseases; Dogs; Malassezia; Pityriasis; Preservation, Biological
PubMed: 1803241
DOI: 10.1111/j.1439-0507.1991.tb00675.x -
Veterinary Immunology and... Aug 2020In this study, dogs with atopic dermatitis were separated into non-food-induced atopic dermatitis (NFIAD) group (n = 15) and food-induced atopic dermatitis (FIAD)...
In this study, dogs with atopic dermatitis were separated into non-food-induced atopic dermatitis (NFIAD) group (n = 15) and food-induced atopic dermatitis (FIAD) group (n = 37) based on an elimination diet test. IgE reactivity for crude Malassezia pachydermatis (M. pachydermatis) and house dust mites (HDM) allergen extracts was investigated in the two groups using fluorometric enzyme-linked immunosorbent assay (ELISA) and intradermal skin test (IDST). Nine (60%) of the 15 dogs in NFIAD group and 6 (16%) of the 37 dogs in FIAD group showed specific IgE for M. pachydermatis (Mann-Whitney U-test, P < 0.01). By immunoblotting analysis, the pooled serum samples from dogs with IgE for M. pachydermatis showed IgE reactivity for 50 kDa protein of M. pachydermatis. Twelve (80%) of the 15 dogs in NFIAD group and 8 (22%) of the 37 dogs in FIAD group showed specific IgE for HDM (Mann-Whitney U-test, P < 0.01). In addition, the dogs in NFIAD group significantly show a positive IDST to M. pachydermatis and HDM extracts compared with the dogs in FIAD group. The results suggest that dogs with NFIAD are at increased risk of becoming sensitized to the normal commensal organism M. pachydermatis compared with dogs with FIAD, perhaps co-sensitization occurred due to an HDM protease antigen's, Der f 1 and/or Der p 1, proteolytic activity related epidermal skin barrier defects. Treatment to limit skin colonization may thus be especially important in NFIAD.
Topics: Allergens; Animals; Cell Extracts; Dermatitis, Atopic; Dog Diseases; Dogs; Food Hypersensitivity; Fungal Proteins; Immunoglobulin E; Intradermal Tests; Malassezia; Mites
PubMed: 32492589
DOI: 10.1016/j.vetimm.2020.110070 -
Mycoses Mar 2017This study aims to evaluate the effect of efflux pump modulators (EPMs) on the minimal inhibitory concentration (MIC) of fluconazole (FLZ) and voriconazole (VOR) in...
This study aims to evaluate the effect of efflux pump modulators (EPMs) on the minimal inhibitory concentration (MIC) of fluconazole (FLZ) and voriconazole (VOR) in Malassezia furfur and Malassezia pachydermatis. The in vitro efficacy of azoles, in combination with EPMs (ie haloperidol-HAL, promethazine-PTZ and cyclosporine A-CYS), against 21 M. furfur from bloodstream infection patients and 14 M. pachydermatis from the skin of dogs with dermatitis, was assessed using a broth microdilution chequerboard analysis. Data were analysed using the model-fractional inhibitory concentration index (FICI) method. The MIC of FLZ and VOR of Malassezia spp. decreased in the presence of sub-inhibitory concentrations of HAL and/or PTZ. The synergic effect was observed only in strains with FLZ MIC≥128 μg/mL for M. furfur, FLZ MIC≥64 μg/mL for M. pachydermatis and VOR MIC≥4 μg/mL in both Malassezia spp. These results suggest that the drug efflux pumps are involved as defence mechanisms to azole drugs in Malassezia yeast. The synergism might be related to an increased expression of efflux pump genes, eventually resulting in azole resistance phenomena. Finally, the above FLZ and VOR MIC values might be considered the cut-off to discriminate susceptible and resistant strains.
Topics: Animals; Antifungal Agents; Cyclosporine; Dermatitis; Dermatomycoses; Dogs; Drug Resistance, Fungal; Drug Synergism; Fluconazole; Genes, MDR; Haloperidol; Humans; Malassezia; Microbial Sensitivity Tests; Promethazine; Skin; Voriconazole
PubMed: 27774659
DOI: 10.1111/myc.12577 -
Medical Mycology Case Reports Jul 2014A case of Malassezia pachydermatis fungemia in a preterm neonate is described. The isolate was identified by rDNA sequencing and was resistant to fluconazole and...
A case of Malassezia pachydermatis fungemia in a preterm neonate is described. The isolate was identified by rDNA sequencing and was resistant to fluconazole and flucytosine. Since M. pachydermatis does not require lipid supplementation for growth, it can be misidentified as a Candida species. The report highlights M. pachydermatis as a cause of late onset sepsis in preterm neonates and emphasizes the need for prior antifungal susceptibility testing.
PubMed: 24936403
DOI: 10.1016/j.mmcr.2014.04.004 -
Veterinary Microbiology Jul 2018The yeast Malassezia pachydermatis is a component of the microbiota of dogs and cats, however it can cause otitis and seborrheic dermatitis in these animals. The...
The yeast Malassezia pachydermatis is a component of the microbiota of dogs and cats, however it can cause otitis and seborrheic dermatitis in these animals. The objective of this study was to determine the antifungal susceptibility, and evaluate virulence and pathogenicity of 25 M. pachydermatis strains from animals. Susceptibility to ketoconazole, fluconazole, itraconazole, voriconazole, terbinafine, and amphotericin B was evaluated by broth microdilution assay. In addition, biofilm-forming ability, protease, phospholipase, hemolysin and melanin production and adhesion to epithelial cells by this yeast species were assessed. Finally, strain pathogenicity was investigated using the nematode Caenorhabditis elegans. Concerning the planktonic susceptibility, minimum inhibitory concentrations varied from <0.03 to>64 μg/mL for azole derivatives, 1 to >16 μg/mL for amphotericin B and 0.03 to 0.25 μg/mL for terbinafine. All strains were classified as strong biofilm producers, and ketoconazole, fluconazole and amphotericin B presented the best inhibitory effect against mature biofilms. All fungal isolates produced proteases, whereas 14/25 strains were positive for phospholipase production. Hemolytic activity was not observed and 18/25 strains showed dark pigmentation in the presence of L-DOPA. Regarding adhesion to epithelial cells, a low adhesion rate was observed in 10/12 evaluated strains. C. elegans mortality rate reached 95.9% after 96 h of exposure of the worms to M. pachydermatis. This yeast species produces important virulence factors and presents high pathogenicity, corroborating its clinical importance.
Topics: Animals; Antifungal Agents; Bacterial Adhesion; Biofilms; Caenorhabditis elegans; Cat Diseases; Cats; Dermatomycoses; Dog Diseases; Dogs; Epithelial Cells; Fluconazole; Foxes; Itraconazole; Ketoconazole; Malassezia; Microbial Sensitivity Tests; Peptide Hydrolases; Phospholipases; Virulence
PubMed: 29885800
DOI: 10.1016/j.vetmic.2018.05.003 -
Emerging Infectious Diseases Jan 2005Yeasts of the genus Malassezia serve as both commensal microorganisms and pathogens on the skin of humans and domestic animals. Although rare, cases of life-threatening...
Yeasts of the genus Malassezia serve as both commensal microorganisms and pathogens on the skin of humans and domestic animals. Although rare, cases of life-threatening fungemia in people have been attributed to Malassezia pachydermatis, for which dogs are a natural host. Zoonotic transfer has been documented from dogs to immunocompromised patients by healthcare workers who own dogs. We investigated the role of pet dogs as risk factors for mechanical carriage of M. pachydermatis on human hands. Dogs and their owners were sampled as pairs, by fungal culture and nested polymerase chain reaction (PCR). Although fungal culture was not a reliable means by which to detect carriage of the yeast on human hands, PCR identified M. pachydermatis on most (approximately equal to 93%) human participants. Human carriage of ubiquitous opportunistic pathogens such as M. pachydermatis underscores the importance of good hand hygiene by healthcare professionals.
Topics: Animals; Animals, Domestic; Carrier State; Dermatomycoses; Dog Diseases; Dogs; Hand; Humans; Malassezia; Skin; Zoonoses
PubMed: 15705327
DOI: 10.3201/eid1101.040882