Vortexing or manual or mechanical shaking of the samples yielded comparable counts. Method for the determination of broth dilution minimum inhibitory concentrations of antifungal agents for yeasts, Assessment of the antifungal susceptibility of Malassezia pachydermatis in various media using a CLSI protocol, Genotyping and antifungal susceptibility testing of multiple, Methodological issues in antifungal susceptibility testing of, Diffusion Procedures for Susceptibility Testing of, European harmonization of MIC breakpoints for antimicrobial susceptibility testing of bacteria, Evaluation of the antifungal susceptibility of, Posaconazole (Noxafil): a new triazole antifungal agent, Antifungal activity of the allylamine derivative terbinafine in vitro, Comparison of in vitro antifungal activities of topical antimycotics launched in 1990s in Japan, Determining canine skin concentrations of terbinafine to guide the treatment of, Principles and practice of clinical mycology, Incidence and treatment of budding yeasts in canine otitis externa, Sterol composition in polyene antibiotic‐sensitive and resistant strains of, Activity of chlorhexidine shampoos in vitro against, In vitro antimicrobial activity of a commercial ear antiseptic containing chlorhexidine and Tris‐EDTA, Comparative in vitro efficacy of antimicrobial shampoos: a pilot study, In vitro growth versus inhibition of growth of, Blad‐containing oligomer: a novel fungicide used in crop protection as an alternative treatment for tinea pedis and tinea versicolor, Blad‐Containing Oligomer Fungicidal Activity on Human Pathogenic Yeasts. Recent genomic studies have elucidated previously problematical aspects of taxonomy and indicated that genotypes and species of Malassezia are evolving as an adaptation to particular host ecological niches. Pour toutes informations supplémentaires ou pour contacter un vétérinaire spécialiste, « Une recherche d'excellence depuis 1836 ». There have been significant advances in the understanding of the mechanisms of interaction between Malassezia yeasts and their hosts. ─ not reported, AD atopic dermatitis, HS healthy skin, LS lesional skin, PV pityriasis versicolor, SD seborrhoeic dermatitis, OT otitis. Cutaneous responses to the application of viable and killed Malassezia have been assessed both clinically and histologically in laboratory animals (guinea pigs, mice, rabbits) and humans, primarily with “lipid‐dependent” Malassezia species isolated from humans (whose nomenclature pre‐dates current revised taxonomy) applied under occlusion.321-324 Lesions generally comprised focal areas of scaling that most often resolved without treatment upon discontinuation of inoculation and were characterised histologically by yeast cells or hyphae in the stratum corneum, variable epidermal hyperplasia and superficial dermal inflammation with granulocytes and lymphocytes. However, it is also important to remember that in some cases, especially in predisposed breeds, there is no identifiable underlying cause and the dog's skin disease may respond completely to antifungal therapy. In one review,87 it was proposed that Malassezia yeasts are potential pathogens that operate in a pliable, physiological “transitional mantel zone” that is influenced by both host skin and the animal's external environment. Based on the above studies, the likely sequence of events leading to immune responses to, By continuing to browse this site, you agree to its use of cookies as described in our, I have read and accept the Wiley Online Library Terms and Conditions of Use, Diagnosis and treatment of dermatophytosis in dogs and cats: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology, Strength of recommendation taxonomy (SORT): a patient‐centered approach to grading evidence in the medical literature, A phylogenetic hypothesis of Ustilaginomycotina based on multiple gene analyses and morphological data, Moniliellomycetes and Malasseziomycetes, two new classes in Ustilaginomycotina, Genomic insights into the atopic eczema‐associated skin commensal yeast, Draft genome sequence of the animal and human pathogen, A deviation from the bipolar‐tetrapolar mating paradigm in an early diverged basidiomycete, Ultrastructural features of the dimorphic yeast, Microtubular and actin cytoskeletons and ultrastructural characteristics of the potentially pathogenic basidiomycetous yeast, Traité de Botanique Médicale Cryptogaminique, Biodiversity, phylogeny and ultrastructure, Malassezia and the skin. In a similar study of eight healthy cats, itraconazole compounded in both capsules and suspension was absorbed poorly and inconsistently.441 In a field study of 95 dogs and 20 cats receiving either compounded, generic or innovator‐formulated itraconazole for systemic mycoses, sub‐therapeutic concentrations were detected in 95.2% of animals receiving the compounded formulation but in only 12.5% or less of the animals treated with generic or reference formulations.442 The poor bioavailability of itraconazole in compounded formulations and in some cases treatment failures, has been attributed to the absence of cyclodextrin, a carrier compound shown to improve gastro‐intestinal absorption.443, 444 A study of compounded fluconazole suspensions showed poor pharmaceutical accuracy (median 74% of target concentration).445 These data indicate that use of compounded azole formulations must not be used; innovator‐formulated or proven generic formulations are preferred. Malassezia species are lipid dependent due to an inability to synthesize long‐chained (C14 or C16) fatty acids de novo.30 There are some differences in lipid dependence among the species and this variability has been used for the development of specific tests for the identification.31 Historically M. pachydermatis was regarded as being “lipophilic but not lipid‐dependent” because it was the only member of the genus to grow on Sabouraud's dextrose agar. Co‐proliferation of staphylococci in the same lesions145 may exacerbate clinical signs and necessitates concurrent antibacterial therapy in some cases.146 The term ‘dysbiosis’ has been applied to similar microbial imbalances within the cutaneous microbiome, albeit primarily in the context human and canine atopic dermatitis (cAD).118, 147-149, The Malassezia genus’ evolution to lipid‐dependency is associated with a wide expansion of lipase and phospholipase genes, and loss of carbohydrate metabolism genes, although numbers of secreted proteins overall appear lower than those of related plant pathogens (Section 2).150 Lipases, highly expressed in the skin of human patients with dandruff and seborrhoeic dermatitis, likely damage the epidermal barrier directly and by hydrolysis of triglycerides.151-153 Phospholipase activity in M. pachydermatis is stimulated by the endogenous opioid peptide ß endorphin present in the skin of dogs with dermatoses;154 activity was significantly higher amongst M. pachydermatis isolates derived from the dogs with otitis externa155 or skin lesions156, 157 when compared with those obtained from the dogs with healthy external ears, or non‐lesional skin, respectively. Activation of keratinocytes by Malassezia is suggested by studies in humans which demonstrated that M. furfur could invade keratinocytes and resist phagolysosome fusion.178, 179 Furthermore, M. sympodialis produces extracellular vesicles, enriched with the allergens Mala s 1 and s 7, that bind actively to and are internalised by human keratinocytes, potentially promoting sensitisation and maintenance of inflammation.180, Keratinocytes recognise Malassezia antigens via Toll‐like receptors,174 although they, along with other cells, can also be activated via the aryl hydrocarbon receptor following stimulation with Malassezia furfur‐derived indole alkaloids such as malassezin, indirubin and indolo carbazole.175 These tryptophan‐derived metabolites can trigger a variety of effects such as apoptosis of human melanocytes, but their precise role in cutaneous pathology remains to be determined. Frequency of isolation (%) of Malassezia pachydermatis from skin and mucosal sites in selected studies of healthy dogs of varying breeds. pronounced irregular epidermal and infundibular hyperplasia; prominent epidermal and infundibular parakeratotic hyperkeratosis; diffuse epidermal and infundibular intercellular oedema (spongiosis); diffuse epidermal and infundibular lymphocytic exocytosis; superficial perivascular to interstitial dermatitis wherein lymphocytes are a prominent inflammatory cell type. Malassezia est considérée comme un organisme normal présent sur la peau. Learn about our remote access options, Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, AL9 7TA UK, Correspondence: Ross Bond, Department of Clinical Sciences and Services, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, AL9 7TA, UK. Unlike the dermatophytes, which visit and potentially infect the non‐immune host, Malassezia yeasts are commensal organisms, forming a reservoir of potential pathogens in the stratum corneum or mucosae, that may induce disease whenever the homeostatic balance of yeast virulence, on the one hand, and host immunity, on the other, is disrupted in favour of the yeast. Few phenotypic tests are available to differentiate Malassezia species and some of them may overlap. The histopathological features of skin diseases where Malassezia spp. Contact plate counts from the trunk were significantly higher in healthy Devon rex cats when compared to healthy domestic short‐haired cats and Cornish rex cats; seborrhoeic Devon rex and sphynx cats had high yeast counts that exceeded those of the other groups.80, 116 Contact plates were also used in two studies that assessed the beneficial therapeutic effects of oral itraconazole in cats with Malassezia dermatitis.86, 284. Table S4. Studies utilising traditional cytological and cultural methods have clearly demonstrated that Malassezia yeasts are normal inhabitants of healthy canine and feline skin and mucosae (Section 4).58, 65, 73, 81, 94, 104, 255-257 It is also clear that Malassezia overgrowth is a feature of a variety of clinical presentations in dogs98, 102, 107, 145, 245, 258 and cats.81, 82, 85, 115, 259 More recently developed molecular techniques have the advantage of being able to detect minority populations or organisms that cannot be cultivated using routine methods148, an issue that hindered progress with the lipid‐dependent Malassezia spp. Only one retrospective study of 12 cases of generalised Malassezia dermatitis reported treatment with a 0.2% enilconazole lotion (frequency of application not detailed) in association with oral ketoconazole.437 Although a complete mycological recovery was described, no specific report of clinical improvement was available (LoE 3; SoR not applicable). Studies were either randomized and controlled,146, 379, 424, 427 or controlled without blinding428 (Table 3) involving relatively small group sizes (7‐12 dogs). Microbiome studies utilising next‐generation sequencing have the potential to re‐define the microbial ecology of mammalian skin. La dermatite à levures est une infection de la peau causée par Malassezia pachydermatis. Terbinafine is a synthetic allylamine derivative that inhibits fungal ergosterol biosynthesis at the point of squalene epoxidation. Et notamment les otites chez le chien.. Je vous propose de voir comment l’aromathérapie, qui est l’utilisation des huiles essentielles à des fins thérapeutiques, peut aider à traiter les chiens.. L’otite à Malassezia : traitement … Concurrent use of cefalexin in both treatment groups limits full clinical interpretation (LoE 2; SoR B‐moderate). These studies provide convincing evidence that proteins from Malassezia yeasts can act as allergens in dogs predisposed to the development of atopic dermatitis. Imidazoles such as clotrimazole, climbazole and miconazole are used topically (most commonly in otic products, creams or shampoos) although ketoconazole and its triazole derivative itraconazole are widely available for oral use in dogs and cats. Molecular biological techniques have transformed the taxonomy of the genus from two species in 1989 to 18 species at the time of publication, in the process explaining, at a stroke, many of the painstaking observations of phenotypic variation made by generations of mycologists. Secondary excoriations may be present in severe cases. that will effectively eliminate carriage of Malassezia yeasts from human hands. Two were comparative versus ketoconazole. Adverse reactions are regularly reported with the use of ketoconazole in dogs; a retrospective study of 632 dogs that received a median daily dose of 10 mg/kg reported adverse effects in 14.6%, including primarily vomiting (7.1%), anorexia (4.9%), lethargy (1.9%) and diarrhoea (1.1%).429 Adverse effects were significantly more frequent in dogs receiving concurrent ivermectin or ciclosporin. As Malassezia yeasts are part of the normal cutaneous microflora, complete elimination of the organism is unrealistic even with effective treatment.447 Relapsing infections are common where there is persistence of the underlying cause for the yeast overgrowth. Terbinafine was first shown to have activity in vitro against Malassezia spp. The authors approached the development of consensus guidelines on therapy on two levels. Of the 15 cats with Malassezia, 11 presented with an acute onset of multifocal to generalized skin lesions and were euthanised or died within two months. A basic description of molecular methods is incorporated to aid the non‐specialist reader in understanding how these techniques are currently applied to yeast identification and epidemiology, and how in future they may change our diagnostic approach to the case. el género Malassezia está compuesto por un grupo de levaduras lipofílicas que han evolucionado como comensales cutáneos y patógenos cutáneos oportunistas de una variedad de mamíferos y aves. 1976: Baxter was the first to report on M. pachydermatis in cat ears and as previously mentioned, found that Malassezia were also present in the ears of healthy animals.61 In 1990 Hajsig and Hajsig confirmed that M. pachydermatis is a normal part of cat skin microflora.73. En poursuivant votre navigation sur ce site, vous acceptez l’utilisation de cookies ou autres traceurs pour vous proposer des informations et offres promotionnelles adaptées à vos centres d'intérêt et réaliser des statistiques de visites. Although M. pachydermatis predominates on both healthy cats and cats with dermatitis, lipid‐dependent species such as M. sympodialis,56, 76 M. globosa,76 M. furfur,77 M. nana,79, 116 and M. slooffiae80, 82, 116 are occasionally encountered. In contrast to humans and dog, Malassezia overgrowth in the cat, in the absence of hypersensitivity disorder or a breed predilection (Devon rex, sphynx) may indicate a poorer prognosis due to an association with life‐threatening systemic diseases. Seborrhoeic dermatoses in dogs have been statistically associated with significantly higher M. pachydermatis skin surface counts as compared to healthy dogs.98, 245 Similar associations have been described in cats with seborrhoeic disorders.80, 115 Endocrinopathies such as hypothyroidism and hyperadrenocorticism may cause secondary seborrhoea in dogs; while no studies have demonstrated either disease to be an independent risk factor for Malassezia overgrowth, cases where an endocrinopathy and Malassezia dermatitis have occurred concurrently have been reported.240, 241, 246 In cats, no differences in Malassezia carriage were noted between healthy controls and cases with either hyperthyroidism or diabetes mellitus, using a contact plate technique for quantitative culture at several body sites; however, it should be noted that the cats with endocrinopathies in this study had no skin lesions at the time of sampling.82, Malassezia overgrowth appears to be favoured by skin diseases with (assumedly) altered stratum corneum barrier function through aberrant cornification. Working off-campus? Case‐control studies in Devon rex cats and the sphynx breed, have demonstrated increased Malassezia counts as compared to domestic shorthaired cats.78, 81, 115, 116 In these cases, Malassezia overgrowth is associated with the clinical finding of seborrhoeic skin; especially in the claw folds.78, Pruritic inflammatory diseases such as atopic dermatitis may create microclimate changes due to scratching (disruption of barrier function), licking (added moisture) or increased production of sebum.107 Despite the clinical observation that Malassezia overgrowth and atopic dermatitis commonly co‐occur,107, 244 studies have sometimes failed to demonstrate a clear statistical association between the two conditions.240, 241 Nevertheless it is generally accepted that M. pachydermatis may increase the inflammation associated with cAD directly by induction of inflammatory cytokines from epidermal cells and indirectly by acting as an allergen234, 239 (Section 6). David Robinson has received funding from or otherwise collaborated with MSD Animal Health, Virbac Animal Health and Elanco. The influence of sampling methods and culture media on yeast counts are reviewed in Section 8. The length of treatment varied between three and four weeks in most cases. The cell wall of Malassezia spp. The presence of Malassezia organisms on the skin, both in normal and excessive numbers, is known to activate the skin immune system.173 There is now compelling evidence that Malassezia antigens can stimulate innate, antibody and cell mediated immune responses, as well as triggering hypersensitivity reactions.174 Although this immune response may offer a degree of protection in certain circumstances, it may also be harmful. Le diagnostic se fait au cours d’une consultation spécialisée de dermatologie. 2002: Mauldin et al.83 evaluated the presence of Malassezia yeasts in feline skin specimens submitted for histopathological examination from 1999 to 2000. The histopathological features in skin biopsy specimens from lesions of Malassezia infection in dogs and cats commonly represent an amalgamation of features reflecting both the host response to the yeast as well as the concurrent, underlying disease. Important breed predispositions are discussed in Section 7.1.67, 240, 241 There is no sex predisposition. Further studies are therefore required to determine the precise role played by these antibodies in Malassezia‐induced skin disease. According to a standard textbook,326 Malassezia may feature in cases of bacterial intertrigo, feline hypersensitivity reactions, acrodermatitis of bull terrier dogs, atopic dermatitis, congenital follicular parakeratosis, facial dermatitis of Persian and Himalayan cats, familial paw pad hyperkeratosis, feline acne, feline paraneoplastic alopecia, feline thymoma‐associated exfoliative dermatitis, female hyperoestrogenism, food allergy, hypothyroidism, ichthyosis, interdigital furunculosis, mucinosis, nasodigital hyperkeratosis, sarcoptic mange, seborrhoeic dermatitis, Sertoli cell tumour‐associated skin disease, superficial necrolytic dermatitis and zinc‐responsive dermatosis (Table S4). L’objectif de ce document est de fournir à la communauté vétérinaire et aux parties intéressées toute l’information actuelle sur l’écologie, la pathophysiologie, le diagnostic, le traitement et la prévention des maladies cutanées associées aux levures Malassezia chez le chien et le chat. isolation from the hair coat as compared to non‐infected cats.254, Antibacterial therapy has not been reported to be an independent risk factor for development of Malassezia dermatitis in any published studies. Less commonly affected regions include the tail and the pinnae, and in contrast with Devon Rex and sphynx cats, the interdigital regions and claw folds.85, 259, 284, Although uncommon, Malassezia overgrowth should be considered in every case of localised or generalised erythema associated with seborrhoea in cats.284, Feline idiopathic facial dermatitis is an uncommon skin disorder of presumed hereditary origin.395 Persian, and anecdotally Himalayan, cats are predisposed.395-397 Affected cats show progressive skin lesions on the face characterised by symmetrical erythema and exudate with black waxy material matting the distal hair particularly in facial folds, perioral, periocular and preauricular regions. Routine cytological sampling of skin sites in the veterinary clinic is best achieved by light microscopical examination (50× or 100x oil objectives) of tape‐strips or dry scrapes stained with modified Wright Giemsa stain (“Diff‐Quik” or generic equivalents). The interaction between Curdlan, a ß‐glucan component of the cell wall of M. sympodialis, and C‐type lectin pattern recognition receptors (such as Dectin‐1) expressed on the surface of human cutaneous mast cells, induced degranulation and augmented IgE‐mediated granule exocytosis.231 In other circumstances, fungal ligands may induce Dectin‐1 mediated mast cell activation and production of chemokines and cytokines without degranulation.231, In order to demonstrate full IgE‐mediated hypersensitivity, it is necessary to document mast cell degranulation following allergen exposure. Traitement de l' otite externe du chien et du chat Dès lors, on comprend que plutôt que de changer maintes et maintes fois d'antibiotiques, et d’incriminer une éventuelle résistance bactérienne, il est préférable et nécessaire d'identifier à la fois un éventuel facteur prédisposant et surtout le ou les facteurs déclenchant à l'origine de l'otite. The GP prepared a detailed literature review and made recommendations on selected topics. Malassezia dermatitis in dogs and cats has evolved from a disease of obscurity and controversy on its existence, to now being a routine diagnosis in general veterinary practice. and you may need to create a new Wiley Online Library account. Utility. Summary of reports on susceptibility testing of Malassezia pachydermatis using the broth microdilution method. Clinical signs are well recognised and diagnostic approaches are well developed. The relative lack of sensitivity of histopathology for detecting Malassezia spp. Topical treatments are preferred to systemic treatments for long‐term therapy because of a lower risk of toxicity. This section comprises a comparative review of human and dog studies; publications on immune reactivity to Malassezia species in cats appear to be lacking. IgM, IgG and IgA antibodies against Malassezia species are present in both young and elderly people, but the amount of IgG and IgM tends to tail off with age corresponding with declining numbers of commensal yeasts.200-202 The Malassezia‐specific IgA concentration was found to be relatively low in all age groups. Il sagit malheureusement du parcours habituel quemprunte la majorité des personnes ayant été mal orientée et ayant un chien souffrant de dermatite atopique. Any queries (other than missing content) should be directed to the corresponding author for the article. Figure S1. A dermatite por Malassezia em cães e gatos evoluiu de uma doença em que a sua existência permanecia na obscuridade e controvérsia, passando a ser um diagnóstico de rotina na prática veterinária em geral. The genus Malassezia (Baillon) was created in 1889 for a single species, M. furfur, observed in lesions of pityriasis versicolor, a common dermatological condition in humans.17 It took a long time to understand the lipid dependence of this kind of fungus and, as a consequence, to obtain and maintain Malassezia yeasts in culture.18 Conventional laboratory techniques could not be used and despite the description of numerous species, their accurate identification was not possible. With respect to prevention of recurrent Malassezia otitis, while studies in vitro have demonstrated antimicrobial efficacy of ear cleaners,451, 452 there are only two studies examining topical therapy for prevention of Malassezia otitis. The only additional treatment for the M. pachydermatis initially isolated in this time was two baths in a selenium sulphide shampoo, indicating a likely strong association between yeast overgrowth and the thymoma.251, Superficial necrolytic dermatitis (syn. Malassezia yeasts (chiefly M. pachydermatis) have been associated with a greasy seborrhoeic dermatitis in cats with or without concurrent paronychia.391 Predisposing diseases include poorly defined genetic factors (in Devon Rex and sphynx cats),80, 86, 115, 116 feline atopic dermatitis (which may present with concurrent bacterial pyoderma),85, 259, 284, 392 adverse food reaction,259, 284 flea bite hypersensitivity,284 although some recurrent cases are idiopathic despite diagnostic investigation.74, 284 There is conflicting evidence for diabetes mellitus as a predisposing cause.82, 284, 393 Feline immunodeficiency virus‐positive cats have been shown to carry more Malassezia organisms compared with normal cats but this was not associated with any clinical signs.394, Affected Devon Rex and sphynx cats typically show mild to marked greasy seborrhoea with alopecia (in Devon Rex) and hyperpigmentation or reddish‐brown surface discolouration and variable erythema affecting the axillae, groin, ventral neck and predominantly ventral interdigital regions. When predisposing factors cannot be identified or controlled in an animal suffering from recurrent Malassezia infections, regular topical or pulsed oral antifungal therapy have been recommended to minimise the frequency of infection relapses that cannot be managed by other means.391, 447, 450, Multiple topical therapies have been shown to be effective for treatment of Malassezia dermatitis in dogs and cats (See Section 15). By contrast, this regimen was not fully effective at reducing otic counts of Malassezia and therefore pulsed dosing cannot currently be recommended for prevention of otitis externa. el objetivo de este documento es proporcionar a la comunidad veterinaria y otras personas interesadas información actualizada sobre la ecología, la fisiopatología, el diagnóstico, el tratamiento y la prevención de enfermedades de la piel asociadas con las levaduras Malassezia en perros y gatos.