Malassezia Dermatitis Research Articles

In-vitro Antifungal Susceptibility of Malassezia Dermatitis in Dogs

Malassezia dermatitis is a highly pruritic type of dermatitis which mainly produces itching, erythema as its primary skin lesion and secondary skin lesions includes scaling, seborrhoea, maldour, lichenification and hyperpigmentation. The present study was conducted to compare the antifungal efficacy of Ketoconazole, Itraconazole, and Terbinafine against Malassezia spp. and to evaluate the antifungal sensitivity of Malassezia species isolated from dermatitis cases in dogs in and around Jabalpur, Madhya Pradesh. A total of 100 skin swabs were collected from dogs with dermatological symptoms suggestive of Malassezia spp., out of which 87 swabs were successfully isolated and showed good growth on Sabouraud’s Dextrose Agar (SDA) during primary isolation from the skin swabs. For this, commercially available antifungal discs of Ketoconazole and Itraconazole were used whereas for Terbinafine antifungal disc was made due to lack of its availability. Based on in-vitro antifungal susceptibility studies, it can be concluded that Ketoconazole, Itraconazole, Fluconazole and Terbinafine were found to be effective against Malassezia dermatitis and can be advocated as the drug of choice for the treatment of Malassezia dermatitis in dogs.

Diagnosis and treatment of Malassezia dermatitis in a Persian cat

The presence of Malassezia fungus on the skin, in both normal and excessive amounts, can activate the skin's immune system in cats. This paper reports a case of a seven-year-old Persian cat named Imo, who presented with eye pain and symptoms of dermatitis during a physical examination. A supporting examination, including a combo test kit and cytology, led to a diagnosis of Malassezia dermatitis. The therapy provided involved cleaning and compressing the wound with a saline solution containing NaCl, administering itraconazole and an oxyfresh water additive, injecting marbofloxacin subcutaneously, and applying vaseline topically. The patient showed noticeable improvement in wound healing within 24 days of hospitalization

A single-blind randomised study comparing the efficacy of fluconazole and itraconazole for the treatment of Malassezia dermatitis in client-owned dogs.

No reports have compared the clinical therapeutic efficacy of fluconazole and itraconazole in canine Malassezia dermatitis. The study aimed to compare the clinical therapeutic efficacy of fluconazole and itraconazole and to evaluate the adverse effects of fluconazole in canine Malassezia dermatitis. Sixty-one client-owned dogs with Malassezia dermatitis. The enrolled animals were randomly divided into groups receiving 5 mg/kg fluconazole (5FZ), 10 mg/kg fluconazole (10FZ) or 5 mg/kg itraconazole (5IZ). The drugs were orally administered once daily for 28 days. Cytological examination, clinical index score (CIS), pruritus Visual Analog Scale (PVAS) evaluation and blood analysis (for 5FZ only) were performed on Day (D)0, D14 and D28. On D14, significant reductions in mean yeast count (MYC), CIS and PVAS were observed in the 5FZ (n = 20, p < 0.01), 10FZ (n = 17, p < 0.01) and 5IZ (n = 16, p < 0.05) groups. In all three groups, a significant reduction (p < 0.001) in MYC, CIS and PVAS expression was observed on D28. There was no significant difference in the percentage reduction of MYC, CIS and PVAS among the groups. Moreover, there was a significant difference (p < 0.05) in each group between D14 and D28, except for the percentage reduction in MYC in the 10FZ and 5IZ groups. No adverse effects of fluconazole were observed in the 5FZ or 10FZ groups. This study indicates that 5FZ and 10FZ are as effective as itraconazole in canine Malassezia dermatitis.

FUNGAL DERMATITIS INFECTION OF MALASSEZIA SPP. IN MIXED BREED DOG

Malassezia dermatitis is a skin disease caused by fungi of Malassezia spp. that can be superficial and systemic with local or generalised lesions. The purpose of this report is to diagnose and determine the therapeutic success of dermatitis caused by Malassezia spp. fungal infection systemically with generalised and chronic lesions. An 8-year-old mixed breed dog weighing 6.41 kg was examined at the Veterinary Internal Medicine Laboratory, Faculty of Veterinary Medicine, Udayana University with complaints of itching and hair baldness. Clinical examination found generalised alopecia with thickening of the skin, hyperpigmentation on the neck and dorsal region of the body, erythema and papules on the abdominal flank and caudal extremity of the lateral femoral, and scale on the head area. Cytological examination of the skin taken by impression smear found the fungal agent Malassezia spp. Routine haematological examination showed that the dog had lymphocytosis, and hypochromic normocytic anaemia. Based on anamnesis, physical examination, and supporting examination, the dog was diagnosed with dermatitis caused by a Malassezia spp. fungal infection with a fausta prognosis. The dog was treated with oral ketoconazole, chlorpheniramine maleate, fish oil, sebasol shampoo, and dryfood (Dograng classic®). The results of therapy on the 28th day showed that the dog's condition was getting better as indicated by significant hair growth. Therefore, to avoid recurrent infections owners need to avoid keeping their dogs in damp places and stop using human shampoos and dish soaps to bathe their dogs as they can affect the pH of the skin, triggering fungal growth.

Prevalence of dermatophytosis and Malassezia infection in dogs and cats in Thonglor Bangkok Pet Hospital in Ho Chi Minh City, Vietnam

Malassezia yeasts are occasional human and animal skin organisms that commensally act as pathogens, while dermatophytes are common fungi in many clinics and hospitals. The aim of this study was to evaluate the prevalence of dermatophytosis and Malassezia infections in dogs and cats, and the effect of treatments. The study was carried out from December 2022 to May 2023 in Thonglor Bangkok Pet Hospital, Ho Chi Minh City, Vietnam. Total 208 cases visited the hospital, in which 32 cases of otitis and 53 dermatitis were recorded. Sterile cotton swabs were used to collect the aural samples from 32 cases, then observed under the microscope to detect the presence and population of Malassezia yeasts. In 53 dermatitis cases, adhesive tape impressions (ATI) methods and fungal culture were used to identify the species of dermatophytes and Malassezia dermatitis. The results showed that Malassezia was isolated from 24 cases, including 23 Malassezia otitis and 1 Malassezia dermatitis. However, there was only one positive case with dermatophyte by two methods.Therefore, dermatophytosis could not be concluded due to the small number of positive cases. Meanwhile, Malassezia infection occurred mainly in dogs rather than cats at every age, and the infected rates were found more in exotic animals than in domestic animals and usually in males than females. The effect of treatments illustrated the significant improvement in Malassezia otitis by using Epiotic solution combined with Oridemyl ear drop. Moreover, great improvement was evident in dermatophytosis therapy with Itraconazole.

Dermatological Problems of Brachycephalic Dogs

Brachycephalic dogs are not only affected by brachycephalic obstructive airway syndrome (BOAS), but are also frequently referred to veterinary dermatologists for skin conditions, with English bulldogs and pugs particularly over-represented. Some skin diseases, such as skin fold dermatitis, are directly associated with the abnormal anatomic conformation of brachycephalic dogs, while for others, such as atopic dermatitis and viral pigmented plaques, there is an underlying genetic basis or a general predisposition. Anatomic alterations associated with brachycephaly, leading to fold formation of the skin and stenosis of the ear canal, together with primary immunodeficiencies described in some breeds, favor the development of pyoderma, Malassezia dermatitis, and otitis externa/media. In addition, the frequently neglected but often lifelong dermatological problems of brachycephalic dogs are an important consideration when discussing genetic and medical conditions affecting the welfare of those dogs. Here we review the current state of knowledge concerning dermatological problems in brachycephalic dogs and combine it with clinical experience in the management of these challenging disorders.

Azole and terbinafine susceptibility testing of Malassezia pachydermatis in Japan.

Canine Malassezia dermatitis and otitis externa are generally treated by antifungal drugs. However, multi-drug-resistant strains of Malassezia pachydermatis have been reported worldwide. Given the presence of these multi-drug-resistant strains, it is unclear which antifungal agent is the most effective for canine Malassezia dermatitis and canine otitis. In this study, we attempted to determine the most effective drug against azole-resistant M. pachydermatis. Susceptibility to azoles and terbinafine (TBF) was assessed using a modified broth microdilution method. In all tested isolates, the minimum inhibitory concentration at 90% of organisms (MIC90) were 16 to >32 μg/mL for the azoles, and 2 μg/mL for TBF. All of the strains that showed low susceptibility to both itraconazole and miconazole were also relatively susceptible to TBF.

Haemato-biochemical and trichographic studies on mucocutaneous lesions in dogs

The present study was carried out with the objective of assessment of haematobiochemical and trichographic features of mucocutaneous lesions in dogs. Dogs presented with mucocutaneous lesions associated with various dermatological conditions were included in the study. Mange, atopic dermatitis, dermatophytosis, juvenile cellulitis, pyoderma and hypothyroidism with secondary Malassezia dermatitis were presented with mucocutaneous lesions in the perioral, periorbital and in the nostrils with least involvement of anogenital region. Haemato-biochemical analysis revealed anaemia, non-significant increase in total leucocyte count, neutrophilia, eosinophilia, elevated platelet count, hyperproteinaemia and hypoalbuminaemia. Elevated serum C-reactive protein was evident in all cases. Trichographic features revealed that highest number of hairs were included in the telogen phase of hair cycle with greater number of primary hairs. Hair fractures were evident in 20.8 per cent of hairs and trichoptilosis of hair tip was observed in 50.8 per cent of hairs studied. Demodex mites could be detected by hair pluck examination in all cases of demodicosis.

Efficacy of a Silver-Based Shampoo for Treatment of Canine Malassezia: A Pilot Study.

Malassezia pachydermatis is a commensal of canines associated with Malassezia dermatitis. Consensus guidelines recommend topical and/or systemic treatment, but resistance to antifungals has been reported. The objective of this pilot study was to determine the efficacy of a 0.003% colloidal silver nanoparticle-based shampoo in the treatment of canine Malassezia dermatitis. Dogs were included based on compatible history, presentation, and at least one positive cytology. Fourteen privately owned dogs were bathed every 48 hr for up to 28 days, allowing 5-10 min of contact time. The mean Malassezia organisms for 10 oil immersion fields at each Malassezia dermatitis-affected body area was recorded at days 0 and 14. Dogs positive on day 14 had cytologies performed on day 28. Eleven dogs (78.6%) were cytologically negative by day 28. Nine (81.8%) of these were negative by day 14. One dog (7.14%) had partial resolution (negative in 3/4 Malassezia dermatitis areas) by day 28. These results suggest that silver nanoparticle-based shampoo may be effective in the treatment of canine Malassezia dermatitis. Larger, controlled studies are needed to further investigate efficacy, optimal concentration, and ideal application frequency.

Efficacy of Antimicrobial Treatment in Dogs with Atopic Dermatitis: An Observational Study.

Simple SummaryAtopic dermatitis (AD) is a very common allergic skin disease of dogs that is usually accompanied by skin infections, bacterial, fungal, or both. Although treatment of bacterial and fungal infections in dogs with AD has been recommended and is widely practiced, there are only a few studies evaluating its efficacy. The aim of this study was to evaluate the change in the severity of skin lesions and pruritus after the administration of systemic antimicrobials that resulted in the resolution of the infections. In total, 39 dogs were used, and treatment was prescribed according to the laboratory findings. For the evaluation of the skin lesions and pruritus, validated scales were used, and the scores before and after the treatment were compared. The severity of skin lesions and pruritus decreased significantly, by 30% and 35%, respectively. The efficacy of antimicrobial treatment was assessed as good to excellent by the clinician and the owner in 55% and 60% of the dogs, respectively. There was high variability in the response to treatment among dogs and further studies are needed to find factors that can predict the response to antimicrobial treatment in dogs with AD and skin infections.There is a shortage of studies reporting the efficacy of antimicrobial treatment of dogs with atopic dermatitis (AD) and skin infections (SIs). The aim of this study was to evaluate the change in the severity of skin lesions and pruritus, and the overall efficacy of antimicrobial treatment, in dogs with AD and bacterial overgrowth/infection and/or Malassezia dermatitis. A total of 20 dogs with AD and SIs were prospectively enrolled (group A) and they were examined before and after the administration of systemic antimicrobials that resulted in the resolution of SIs. In addition, 19 dogs fulfilling the same inclusion criteria and treated with systemic, with or without topical antimicrobials, were included retrospectively (group B). Since there were no major differences between the groups, their results were combined. The severity of skin lesions decreased significantly, by 30% based on Canine Atopic Dermatitis Extent and Severity Index-4 (CADESI-4), by 28.1% based on the erythema domain of CADESI-4 and based on owner’s global assessment of the severity of skin lesions. Pruritus decreased significantly, by 34.7% based on the Pruritus Visual Analogue Scale (PVAS). The efficacy of antimicrobial treatment was assessed as good to excellent by the investigator and the owner in 55% and 60% of the dogs, respectively. Despite the significant improvement, there was high variability in the response to treatment among dogs. Further studies are needed to find factors that determine the response to antimicrobial treatment in dogs with AD and SIs.

The efficacy of a novel topical spray composed of sodium benzoate, alcohol and botanical oils for the treatment of Malassezia dermatitis in dogs - a split body, randomised, blinded study.

Treatment of Malassezia pachydermatis dermatitis can be performed by systemic or topical route. As M.pachydermatis is located on the stratum corneum, topical therapy alone may be sufficient to resolve the infection. Owing to systemic antifungal resistance and adverse effects, topical treatment alone may improve treatment outcome. To evaluate the efficacy of a topical spray composed of sodium benzoate, alcohol and botanical oils, compared to a shampoo containing 2% chlorhexidine gluconate and 2% miconazole nitrate for the treatment of Malassezia pachydermaitis dermatitis in dogs. Sixteen client owned dogs diagnosed with symmetrical interdigital lesions as a result of secondary Malassezia dermatitis. The study design was prospective, randomised and single-blinded, using a split body protocol. Malassezia yeasts were determined by cytology at the inclusion day (day0) and after treatment (day14). All dogs were treated during 14 days with both shampoo at one paw and spray on the other paw. At day 14 a reduction of Malassezia dermatitis was shown at both paws. No statistical difference was demonstrated between treatment with shampoo or spray. We could not show a difference in efficacy between application of the test spray once daily and the topical use of 2%miconazole/2%chlorhexidine shampoo every other day. No adverse effects were reported.

In vitro antifungal activity of cold atmospheric microwave plasma and synergistic activity against Malassezia pachydermatis when combined with chlorhexidine gluconate

BackgroundThe antifungal efficacy of cold atmospheric microwave plasma (CAMP) against Malassezia pachydermatis has not been to be evaluated.ObjectiveTo examine the antifungal effects of CAMP against M. pachydermatis and its synergistic effects with chlorhexidine gluconate (CHX).MethodsA M. pachydermatis isolate was collected from a dog with otitis externa and Malassezia dermatitis at the Seoul National University Veterinary Medical Teaching Hospital. The antifungal effect was determined by applying CAMP to a M. pachydermatis isolate that was incubated for 3 days at 37°C. After 1, 2, 3 and 5 min of application, the efficacy of the plasma treatment was determined according to the number of colony forming units (CFUs). A mixture consisting of inoculum and CHX was applied to evaluate the synergistic effect of the plasma treatment in the same way.ResultsThe application of CAMP showed significant antifungal effects against M. pachydermatis. The antifungal effect of CAMP was enhanced by an increased exposure time and output power. The application of CAMP with 0.02% and 0.2% CHX resulted in lower survival rates against M. pachydermatis when compared with its sole application at 1 or 2 min.ConclusionsThe study findings demonstrate that CAMP has a potential as a new antifungal option for M. pachydermatis and has synergistic antifungal effects with CHX in vitro. Clinical applications for CAMP are necessary to assess the antifungal efficacy for patients.

Virulence determinants of Malassezia pachydermatis isolated from cases of canine dermatitis

Malassezia is a commensal organism known to cause disease under favourable conditions, and has been isolated from many animals as well as human beings. Malassezia pachydermatis is the most common cause of yeast dermatitis in dogs and there are many determinants involved in the production of disease in the host. This study aims to deterimine the presence of virulent determinants of the organisms isolated from fifteen dogs with dermatitis that may be involved in the pathogenic mechanism of Malassezia. The virulence determinants of M. pachydermatis viz; adherence, cellular surface hydrophobicity and biofilm formation were investigated. All the isolates studied were shown to produce all the virulent factors investigated in vitro which can be compared to the biological system. Adherence of organism on polystyrene plates was evident in all the isolates and the values ranged from 0.14 to 63 per cent with five isolates showing high adherence values. Hydrophobicity was variable and ranged from 1.78 to 69.46 per cent by two phase system with seven isolates showing moderate property. All the isolates were shown to produce biofilm by crystal violet staining technique and the optical density values ranged from 0.075 to 0.56 at 620 nm. No significant correlation was observed between the three virulent determinants examined. The presence of three virulent determinants investigated warrants their consideration in further studies for assessing the pathogenicity of Malassezia dermatitis in dogs.

Occurrence of canine malassezia dermatitis and otitis in Thrissur, Kerala

The aim of this study was to assess the occurrence of malassezia infection in dogs from Thrissur in relation to various predisposing factors such as age, breed, sex and season. One hundred and sixty-four cases of malassezia infection were identified between March 2021 and August 2021. The highest occurrence was noted in the age group of one to six years while least was seen in geriatric dogs above six years of age. Breed predisposition was found in Labrador and Pugs. Occurrence was higher in females than in males. August, July and June were the most favourable months for malassezia infection, while least cases were seen in May.

Reversible infertility in male dog following prolonged treatment of Malassezia dermatitis with ketoconazole

BackgroundKetoconazole, an antifungal agent, adversely affects spermatogenesis in rodents, but knowledge on adverse effects of prolonged administration of ketoconazole on the fertility of male dogs is lacking. A case of reversible infertility with azoospermia in a male American Staffordshire terrier treated with ketoconazole is reported here.Case presentationA seven-year old male American Staffordshire terrier treated for 3 months with ketoconazole for a persistent Malassezia dermatitis displayed reduced libido and mating of 3 bitches had been unsuccessful. The dog was presented at the clinic 40 days after the treatment had been stopped. At first presentation, low libido and complete absence of sperm in the ejaculate (azoospermia) associated with low testosterone level were found. Repeated examinations revealed that sperm quality and testosterone level had restored 100 days after ketoconazole had been withdrawn. Thereafter, the dog successfully mated 2 bitches.ConclusionThe treatment with ketoconazole for 3 months may have led to reversible infertility characterized by azoospermia. Therefore, owners of stud dogs should be informed of this risk prior to initiating such treatment and in case of infertility, previous treatment with ketoconazole should be considered as a possible cause.

A novel cytological technique for bacterial detection on canine skin.

Cytological examination of the skin is an important diagnostic technique in dermatology for disease diagnosis and monitoring of treatment. Impression smear and tape-strip preparation are gold standard cytological techniques. This study introduces a novel cytological method, slurry preparation, in which debris collected from the skin surface is macerated in warm sterile water and dried on the slide. To compare organism yield between a novel and two standard cytological collection techniques by evaluating bacteria and Malassezia yeast counts. Thirty client-owned dogs diagnosed with atopic dermatitis and lesions consistent with pyoderma and/or Malassezia dermatitis. In a prospective, blinded comparison study, dermatological lesions from each dog were sampled using impression smear, tape-strip and slurry preparation methodologies. Ten random reticle fields per lesion, accounting for a total area of 6.25 × 10-3 mm2 (equivalent to ˜5% of a typical ×40 field), were evaluated by light microscopy for each cytological method. Bacterial and Malassezia organisms were measured as counts/sample. The slurry preparation was compared to each of the standard methodologies separately using paired Student's t-tests. The slurry preparation was demonstrated to be more sensitive than gold standard techniques in detecting bacteria, with mean differences of 12.7 and 13.5 additional bacteria per cytological sample, compared to the impression and tape-strip preparations, respectively. The slurry preparation did not differ significantly in detecting Malassezia organisms compared with impression smear preparation. The tape-strip preparation was demonstrated to be more sensitive than the slurry preparation in the detection of Malassezia organisms, finding a mean difference of 0.22 more organisms per sample. Slurry preparation presents advantages over the gold standard techniques in the detection of bacteria which can help to manage canine pyoderma more appropriately. Performing a slurry preparation in cases of suspected canine pyoderma could be considered as an alternative to the gold standard techniques.

Preliminary evaluation of two bathing methods for the management of Malassezia overgrowth in dogs with atopic dermatitis.

Antifungal shampoos are widely used for canine Malassezia dermatitis. Few studies have evaluated effective bathing methods for atopic dogs with Malassezia overgrowth. To evaluate the efficacy of an emollient bathing product (AFLOAT VET) and 2% miconazole/2% chlorhexidine shampoo (2% MIC/CHX) in atopic dogs, and to evaluate the influence on skin barrier function of both products in healthy dogs. Sixteen atopic dogs with secondary Malassezia overgrowth and 11 healthy dogs. This study was a randomized, single-blinded trial. The dogs were randomly treated with either emollient bathing or 2% MIC/CHX, twice weekly for four weeks. Clinical assessment used the Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI-04), pruritus Visual Analog Scale (pVAS), and cytological evaluation of yeast numbers at Day (D)0, D14 and D28. Skin barrier function was determined by measuring transepidermal water loss (TEWL) after a single bathing procedure with each product in the healthy dogs. The pVAS scores and yeast counts were significantly reduced on D28 compared with D0 in both groups (P<0.05). CADESI-04 was significantly decreased on D28 in the emollient bathing group (P=0.003). There were no significant differences in each endpoint score between the groups. In healthy dogs, TEWL was significantly increased after bathing in both groups (P<0.01). An emollient bathing product can be effective for Malassezia overgrowth in dogs with atopic dermatitis. Bathing with shampoo products might affect skin barrier function even when using an emollient product.

Diagnosis of Malassezia dermatitis and otitis in dogs and cats, is it just a matter of counting?

Diagnosis of Malassezia dermatitis and otitis in dogs and cats, is it just a matter of counting?

Biology, diagnosis and treatment of Malassezia dermatitis in dogs and cats Clinical Consensus Guidelines of the World Association for Veterinary Dermatology.

The genus Malassezia is comprised of a group of lipophilic yeasts that have evolved as skin commensals and opportunistic cutaneous pathogens of a variety of mammals and birds. The objective of this document is to provide the veterinary community and other interested parties with current information on the ecology, pathophysiology, diagnosis, treatment and prevention of skin diseases associated with Malassezia yeasts in dogs and cats. The authors served as a Guideline Panel (GP) and reviewed the literature available prior to October 2018. The GP prepared a detailed literature review and made recommendations on selected topics. The World Association of Veterinary Dermatology (WAVD) Clinical Consensus Guideline committee provided guidance and oversight for this process. The document was presented at two international meetings of veterinary dermatology societies and one international mycology workshop; it was made available for comment on the WAVD website for a period of six months. Comments were shared with the GP electronically and responses incorporated into the final document. There has been a remarkable expansion of knowledge on Malassezia yeasts and their role in animal disease, particularly since the early 1990's. 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. Clinical signs are well recognised and diagnostic approaches are well developed. A range of topical and systemic therapies is known to be effective, especially when predisposing factors are identified and corrected.

Biology, diagnosis and treatment of Malassezia dermatitis in dogs and cats: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology.

Background The genus Malassezia is comprised of a group of lipophilic yeasts that have evolved as skin commensals and opportunistic cutaneous pathogens of a variety of mammals and birds. Objectives The objective of this document is to provide the veterinary community and other interested parties with current information on the ecology, pathophysiology, diagnosis, treatment and prevention of skin diseases associated with Malassezia yeasts in dogs and cats. Methods and material The authors served as a Guideline Panel (GP) and reviewed the literature available prior to October 2018. The GP prepared a detailed literature review and made recommendations on selected topics. The World Association of Veterinary Dermatology (WAVD) Clinical Consensus Guideline committee provided guidance and oversight for this process. The document was presented at two international meetings of veterinary dermatology societies and one international mycology workshop; it was made available for comment on the WAVD website for a period of six months. Comments were shared with the GP electronically and responses incorporated into the final document. Conclusions and clinical importance There has been a remarkable expansion of knowledge on Malassezia yeasts and their role in animal disease, particularly since the early 1990's. 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. Clinical signs are well recognised and diagnostic approaches are well developed. A range of topical and systemic therapies is known to be effective, especially when predisposing factors are identified and corrected.