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Microbiology (Reading, England) Oct 2009Lipophilic yeasts of the genus Malassezia are associated with several skin diseases, such as pityriasis versicolor, Malassezia folliculitis, seborrhoeic dermatitis and...
The cell wall galactomannan antigen from Malassezia furfur and Malassezia pachydermatis contains beta-1,6-linked linear galactofuranosyl residues and its detection has diagnostic potential.
Lipophilic yeasts of the genus Malassezia are associated with several skin diseases, such as pityriasis versicolor, Malassezia folliculitis, seborrhoeic dermatitis and atopic dermatitis, and are also increasingly associated with catheter-related fungaemia. The cell wall components of pathogenic micro-organisms behave as an antigen and/or ligand of the innate immune response. Live cells of Malassezia furfur and Malassezia pachydermatis did not react with an anti-alpha-1,2-mannoside antibody. However, they showed a strong hydrophobicity and reactivity with an anti-beta-1,3-glucan antibody compared to those of C. albicans. The cell wall polysaccharides of M. furfur and M. pachydermatis were isolated and their structures analysed by (1)H and (13)C NMR experiments. Both polysaccharides were shown to be beta-1,6-linked linear galactofuranosyl polymers with a small amount of mannan. The presence of galactomannan on cells of Malassezia species has not been described previously. The galactomannan did not react with an anti-Aspergillus fumigatus monoclonal antibody which has specificity for beta-1,5-linked galactofuranosyl residues. An anti-M. furfur antibody strongly reacted with the galactomannans of M. furfur and M. pachydermatis, but did not react with the galactomannans of Trichophyton rubrum, A. fumigatus or Fonsecaea pedrosoi. The characteristics of the anti-M. furfur antibody suggest that there is potential for diagnosis of Malassezia infections by antigen detection.
Topics: Animals; Antibodies, Fungal; Antibodies, Monoclonal; Antigens, Fungal; Cell Wall; Dermatomycoses; Galactose; Magnetic Resonance Spectroscopy; Malassezia; Mannans; Protein Binding; Rabbits
PubMed: 19389777
DOI: 10.1099/mic.0.029967-0 -
Brazilian Journal of Microbiology :... Apr 2009Thiabendazole, classified as antiparasitic and also used as an antifungal drug, can be found as otological solution indicated for treatment of parasitic and fungal...
Thiabendazole, classified as antiparasitic and also used as an antifungal drug, can be found as otological solution indicated for treatment of parasitic and fungal external otitis in small animals. Malassezia pachydermatis is a yeast recognized as a normal inhabitant on the skin and mucous membranes of dogs and cats. However, it is considered an opportunistic agent that causes external otitis and dermatitis in these animals. The aim of this study was to evaluate the in vitro effect of thiabendazole against 51 isolates of M. pachydermatis using the CLSI Broth Microdilution method that has been adapted for this yeast species (NCCLS, 2002). Based on this test, the Minimum Inhibitory Concentrations (MIC) of thiabendazol was calculated. Subsequently, the susceptibility of each isolate against this antifungal was determined. It was observed that the MIC of thiabendazole against M. pachydermatis ranged from 0.03 to > 4 µg/mL. A total of 13.7% of the isolates were found to be resistant, 47.1% were intermediate and 39.2% were sensitive to the drug. The rate of resistance of the yeasts against thiabendazole was similar to the results previously obtained with other antifungals, while the adapted broth microdilution technique used in this study proved to be efficient.
PubMed: 24031347
DOI: 10.1590/S1517-83822009000200002 -
Parasites & Vectors Mar 2009This case reports the efficacy of metaflumizone plus amitraz spot-on formulation (ProMeris Duo(R); Fort Dodge) against generalized demodectic mange. A two year-old male...
This case reports the efficacy of metaflumizone plus amitraz spot-on formulation (ProMeris Duo(R); Fort Dodge) against generalized demodectic mange. A two year-old male dog presented at clinical examination with poor general condition, diffused alopecia, crusted lesions, pruritus, skin scales and pustules. Demodex mites, Malassezia pachydermatis yeasts and bacteria were diagnosed. The dog was treated with cephalexin and topically with metaflumizone plus amitraz spot on formulation at two weeks intervals until two consecutive skin scrapings resulted negative for mites. The number of adult mites statistically decreased at follow-up with a reduction of approximately 42 and 94% at +14 and +28 days post treatment (p.t.) respectively. Nymphs and larvae could not be detected from +28 day p.t. while eggs were no longer present +42 day p.t. The dog was negative for both bacteria and M. pachydermatis at 14 days p.t., coinciding with improved general clinical conditions, recovering skin lesions and no further signs of pruritus. These results show that metaflumizone plus amitraz associated with the antibiotic therapy is highly effective for treating generalized demodectic mange and could also be effective toward controlling M. pachydermatis opportunistic infections.
PubMed: 19265536
DOI: 10.1186/1756-3305-2-13 -
Veterinary Research Communications Aug 2009The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological profile of the drugs. To assess the value of an...
The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological profile of the drugs. To assess the value of an antibiotic combination of polymyxin B and miconazole this study examined the in vitro synergistic potential of the two drugs on Gram-negative and Gram-positive bacteria and yeast. Antifungal and antibacterial activity was tested by minimum inhibitory concentration (MIC) of broth macrodilution and urea broth microdilution, by fluorescence microscopy and flow cytometry. Synergism was calculated using the fractional inhibitory concentration index (FICi). With Staphylococcus intermedius as target we found up to an eightfold reduction of the individual MICs when both drugs were combined. However, the FICi was 0.63 suggesting no real interaction between the two drugs. With Escherichia coli, Pseudomonas aeruginosa, and Malassezia pachydermatis as targets the antimicrobial drug combination reduced the MICs of polymyxin B and miconazole from fourfold to hundredfold resulting in FICi between 0.06 and 0.5 which defines a synergistic action. Thus, if polymyxin B and miconazole are combined their effect is greater than the sum of the effects observed with polymyxin B and miconazole independently, revealing bactericidal and fungicidal synergism. Our results indicate a strong therapeutic value for the combination of these antimicrobial agents against Gram-negative bacteria and yeast and a weaker value against Gram positive bacteria for clinical situations where these pathogens are involved.
Topics: Anti-Bacterial Agents; Antifungal Agents; Bacteria; Culture Media; Drug Combinations; Drug Synergism; Escherichia coli; Flow Cytometry; Malassezia; Miconazole; Microbial Sensitivity Tests; Microscopy, Fluorescence; Polymyxin B; Pseudomonas aeruginosa; Staphylococcus intermedius; Urea
PubMed: 19085068
DOI: 10.1007/s11259-008-9194-z -
The Canadian Veterinary Journal = La... Aug 2008Fifty dogs with bilateral otitis externa were studied over a 10-month period. The exudates of both external ears were obtained, using sterile swabs, and microorganisms...
Fifty dogs with bilateral otitis externa were studied over a 10-month period. The exudates of both external ears were obtained, using sterile swabs, and microorganisms were isolated according to standard microbiological techniques. Antimicrobial susceptibility testing of Staphylococcus intermedius was done by the agar diffusion method. There was bacterial and/or fungal growth in all of the samples. These were all polymicrobial infections. Anaerobic bacteria were not isolated in any sample. The most common pathogens isolated were S. intermedius and Malassezia pachydermatis. A statistically significant difference (P < 0.05) was observed in the isolation pattern between the right and left ears in 34 of the 50 animals (68%). High resistance rates of S. intermedius strains to penicillin, ampicillin, erythromycin, tetracycline, and clindamycin were found. The results suggest that in bilateral canine otitis externa, each ear should be cultured separately and considered as separate units.
Topics: Animals; Anti-Bacterial Agents; Antifungal Agents; Colony Count, Microbial; Dermatomycoses; Dog Diseases; Dogs; Dose-Response Relationship, Drug; Drug Resistance, Bacterial; Drug Resistance, Fungal; Drug Resistance, Multiple, Bacterial; Drug Resistance, Multiple, Fungal; Female; Malassezia; Male; Microbial Sensitivity Tests; Otitis Externa; Staphylococcal Infections; Staphylococcus; Treatment Outcome
PubMed: 18978972
DOI: No ID Found -
Journal of the American Veterinary... Jan 2006To ascertain whether Malassezia organisms can be detected via cytologic examination and fungal culture of samples from the skin surface of psittacine birds and determine...
OBJECTIVE
To ascertain whether Malassezia organisms can be detected via cytologic examination and fungal culture of samples from the skin surface of psittacine birds and determine whether the number of those organisms differs between unaffected psittacines and those that have chronic feather-destructive behavior or differs by body region.
DESIGN
Prospective study.
ANIMALS
50 unaffected psittacines and 53 psittacines that had feather-destructive behavior.
PROCEDURE
Samples were collected by use of acetate tape strips from the skin of the head, neck, proventer, propatagium, inguinal region, and preen gland area of each bird; 0.5-cm(2) sample areas were examined microscopically for yeast, and samples were also incubated on Sabouraud dextrose agar. Polymerase chain reaction assays specific for Malassezia spp, saprophytic fungi, and Candida albicans were performed on DNA prepared from cultured colonies; nested PCR evaluation for Malassezia pachydermatis was then performed.
RESULTS
Microscopically, 63 of 618 (10%) tape-strip samples contained yeast. Thirty cultured colonies were assessed via PCR assays, and all yielded negative results for Malassezia spp; C albicans was identified in 2 colony samples. The numbers of yeast identified microscopically in psittacines with feather-destructive behavior and in unaffected birds did not differ significantly, and numbers did not differ by body region.
CONCLUSIONS AND CLINICAL RELEVANCE
Yeast were identified infrequently via cytologic examination of samples from the skin surface of unaffected psittacine birds or those that had chronic feather-destructive behavior. If yeast are identified on the skin of birds with feather-destructive behaviors, fungal culture of skin samples should be performed to identify the organism.
Topics: Animals; Behavior, Animal; Bird Diseases; Candida albicans; Colony Count, Microbial; DNA, Fungal; Dermatomycoses; Feathers; Malassezia; Polymerase Chain Reaction; Prospective Studies; Psittaciformes; Skin
PubMed: 16426189
DOI: 10.2460/javma.228.2.216 -
The Journal of Veterinary Medical... Dec 2005The antifungal activity of beta-thujaplicin was evaluated against 51 Malassezia pachydermatis strains isolated from canine ear canals with or without otitis externa. For... (Comparative Study)
Comparative Study
The antifungal activity of beta-thujaplicin was evaluated against 51 Malassezia pachydermatis strains isolated from canine ear canals with or without otitis externa. For comparison, sensitivity tests were performed on M. pachydermatis isolates for nystatin, ketoconazole, and terbinafine HCl, all clinically available antifungal agents. The minimal inhibition concentrations over 50% of the tested isolates (MIC50) were 3.13 microg/ml for beta-thujaplicin and nystatin, 0.016 microg/ml for ketoconazole, and 1.56 microg/ml for terbinafine HCl. The antifungal effect for M. pachydermatis of beta-thujaplicin compared favorably with commercial antifungal agents. None of the 51 M. pachydermatis isolates showed resistance against any of the tested antibiotics investigated in this study. Ten representative isolates of M. pachydermatis were subcultured for 30 generations at concentrations close to the MIC levels of beta-thujaplicin, nystatin, ketoconazole, and terbinafine HCl, and examined to determine whether they had acquired resistance to each drug. As a result, M. pachydermatis was found to achieve resistance more easily for ketoconazole and terbinafine HCl than for beta-thujaplicin or nystatin. The MIC50 of beta-thujaplicin did not change during the course of subculture, and it is thought that the potential development of a resistant strain is low, even with continuous infusion for otitis externa therapy. beta-Thujaplicin is an inexpensive and safe treatment with anti-inflammatory and deodorant effects that can be recommended as an effective remedy for canine otitis externa.
Topics: Animals; Antifungal Agents; Dermatomycoses; Dog Diseases; Dogs; Drug Resistance, Fungal; Ketoconazole; Malassezia; Microbial Sensitivity Tests; Monoterpenes; Naphthalenes; Nystatin; Otitis Externa; Species Specificity; Terbinafine; Tropolone
PubMed: 16397383
DOI: 10.1292/jvms.67.1243 -
Mycobiology Sep 2005To produce a novel antihypertensive angiotensin I-converting enzyme (ACE) inhibitor from yeast, a yeast isolate, designated G-14 showing the highest ACE inhibitory...
To produce a novel antihypertensive angiotensin I-converting enzyme (ACE) inhibitor from yeast, a yeast isolate, designated G-14 showing the highest ACE inhibitory activity was obtained and identified as Malassezia pachydermatis based on morphological, biochemical and cultural characteristics. The maximal extracellular ACE inhibitor production was obtained from M. pachydermatis G-14 when the strain was cultured in YEPD medium containing 0.5% yeast extract, 3.0% peptone and 2.0% glucose at 30℃ for 24 h and the final ACE inhibitory activity was 48.9% under the above condition.
PubMed: 24049490
DOI: 10.4489/MYCO.2005.33.3.142 -
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 -
Journal of Clinical Microbiology Oct 2004An evaluation was made of the phospholipase activities of Malassezia pachydermatis strains isolated from healthy dogs versus those from dogs with dermatitis and otitis....
An evaluation was made of the phospholipase activities of Malassezia pachydermatis strains isolated from healthy dogs versus those from dogs with dermatitis and otitis. A high percentage of strains of M. pachydermatis obtained from lesion sites (93.9%) produced phospholipase, compared to the strains obtained from healthy skin of the same dog with localized lesions (41.4%) and healthy dogs (10.6%).
Topics: Animals; Dermatitis; Dermatomycoses; Dog Diseases; Dogs; Malassezia; Otitis; Phospholipases; Skin
PubMed: 15472366
DOI: 10.1128/JCM.42.10.4868-4869.2004