Comparative analysis of the distribution and antifungal susceptibility of yeast species in cat facial hair and human nails.

Zoonotic yeast species have been implicated in disease development in both humans and cats. This study analyzed the yeast mycobiota present in feline facial hair and human nails and explored potential interspecies associations. A total of 118 biological specimens were examined, including 59 feline facial hair and 59 human nail samples. DNA extraction and DNA sequencing were performed to identify the specific yeast species. The most predominant yeast species in humans and cats were selected for antifungal susceptibility testing (itraconazole, ketoconazole, miconazole, and terbinafine). The findings unveiled diverse yeast species in cats and humans. Malassezia pachydermatis (45.8%) and Malassezia furfur (30.5%) were the most common yeast species in cats and humans, respectively. However, no significant correlation was detected between the yeast species identified in cats and their owners residing in the same household (p > 0.05). Miconazole exhibited the highest minimum inhibitory concentrations (MICs) against Malassezia pachydermatis and Malassezia furfur in both cat and human isolates, whereas terbinafine showed the lowest MICs against most Malassezia pachydermatis and Malassezia furfur in both cat and human isolates. Diverse yeast species in cat facial hair and human nails suggest possible cross-contamination among humans, pets, and environments.

Malassezia restricta as an unexpected cause of infectious osteomyelitis diagnosed by metagenomic sequencing: a case report and literature review.

BACKGROUND: Malassezia restricta, a lipophilic and lipodependent yeast belonging to the basidiomycetes group, is an opportunistic fungal pathogen associated with various skin diseases, including seborrheic dermatitis and dandruff. Typically, Malassezia infection in neonates manifests as fungemia or hematogenous dissemination to the bone or lungs. However, vertebral osteomyelitis caused by these fungi is rarely reported owing to non-specific clinical presentations and laboratory/imaging findings. The Pathogen Metagenomics Sequencing (PMseq) technique enables direct high-throughput sequencing of infected specimens, facilitating the rapid and accurate detection of all microorganisms in clinical samples through comprehensive reports. CASE PRESENTATION: A 52-year-old male was admitted to our hospital on July 20, 2022 with a 3-month history of ambulatory difficulties and localized low back pain. Magnetic Resonance Imaging (MRI) examination of the spinal column revealed irregular bone destruction affecting the L2, L3, and L5 vertebral bodies. Additionally, low T1 and high T2 intensity lesions were observed at the intervertebral discs between L3 and L5. The presumptive diagnosis of tuberculous spondylitis was made based on the imaging findings, despite negative results in all mycobacterium tests. However, the patient exhibited no improvement after receiving regular anti-tuberculosis treatment for 3 months. Subsequent MRI revealed an expansive abnormal signal within the vertebral body, leading to progressive bone destruction. The absence of spinal tuberculosis or other infective microorganisms was confirmed through culture from blood and pathological tissue from the L4 vertebral body. Subsequently, PMseq was performed on the specimens, revealing M. restricta as the predominant pathogen with the highest relative abundance value. The pathological examination revealed the presence of fungal mycelium in the L4 vertebral body, with positive findings on periodic Schiff-methenamine and periodic acid-Schiff staining. The anti-tuberculosis treatment was discontinued, and an antifungal combination of fluconazole and voriconazole was administered. All symptoms were resolved after 7 consecutive months of treatment, and the patient was able to ambulate autonomously. Vertebral lesions were reduced on MRI during the 13-month follow-up. CONCLUSIONS: M. restricta is not a commonly recognized pathogen associated with infectious vertebral osteomyelitis. However, PMseq can aid in diagnosis, timely treatment, and decision making for some non-specific infectious diseases.

Prevalence and genetic diversity of azole-resistant Malassezia pachydermatis isolates from canine otitis and dermatitis: A 2-year study.

Despite previous reports on the emergence of Malassezia pachydermatis strains with decreased susceptibility to azoles, there is limited information on the actual prevalence and genetic diversity of azole-resistant isolates of this yeast species. We assessed the prevalence of azole resistance in M. pachydermatis isolates from cases of dog otitis or skin disease attended in a veterinary teaching hospital during a 2-year period and analyzed the ERG11 (encoding a lanosterol 14-α demethylase, the primary target of azoles) and whole genome sequence diversity of a group of isolates that displayed reduced azole susceptibility. Susceptibility testing of 89 M. pachydermatis isolates from 54 clinical episodes (1-6 isolates/episode) revealed low minimum inhibitory concentrations (MICs) to most azoles and other antifungals, but 11 isolates from six different episodes (i.e., 12.4% of isolates and 11.1% of episodes) had decreased susceptibility to multiple azoles (fluconazole, itraconazole, ketoconazole, posaconazole, ravuconazole, and/or voriconazole). ERG11 sequencing of these 11 azole-resistant isolates identified eight DNA sequence profiles, most of which contained amino acid substitutions also found in some azole-susceptible isolates. Analysis of whole genome sequencing (WGS) results revealed that the azole-resistant isolates from the same episode of otitis, or even different episodes affecting the same animal, were more genetically related to each other than to isolates from other dogs. In conclusion, our results confirmed the remarkable ERG11 sequence variability in M. pachydermatis isolates of animal origin observed in previous studies and demonstrated the value of WGS for disentangling the epidemiology of this yeast species.

We analyzed the prevalence and diversity of azole-resistant Malassezia pachydermatis isolates in a veterinary hospital. A low prevalence of multi-azole resistance (c.10% of isolates and cases) was found. Whole genome and ERG11 sequencing of resistant isolates revealed remarkable genetic diversity.

Mycobiome of the external ear canal of healthy cows.

Malassezia yeasts belong to the normal skin microbiota of a wide range of warm-blooded animals. However, their significance in cattle is still poorly understood. In the present study, the mycobiota of the external ear canal of 20 healthy dairy Holstein cows was assessed by cytology, culture, PCR, and next-generation sequencing. The presence of Malassezia was detected in 15 cows by cytology and PCR. The metagenomic analysis revealed that Ascomycota was the predominant phylum but M. pachydermatis the main species. The Malassezia phylotype 131 was detected in low abundance. Nor M. nana nor M. equina were detected in the samples.

The mycobiota of the external ear canal of healthy cows was assessed by cytology, culture, PCR, and NGS. The presence of Malassezia was detected by cytology and PCR. Ascomycota was the main phylum and M. pachydermatis the main species. The Malassezia phylotype 131 was also detected in the samples.

Prevalence and clinical findings of feline otitis externa in Midwest Brazil.

This study was conducted to evaluate the prevalence of otitis externa (OE) in cats using cytology, direct otoscopic examination, and parasitological examination through swabs and curettage, and to compare the accuracy between collection methods for parasitological examination. Direct otoscopic evaluation of the external auditory canal (right and left), swabs for cytological examination of the external auditory canal, and collection of cerumen for parasitological examination through swabs and curettage of 137 cats from a veterinary hospital care were conducted between March 2021 and March 2022. The influences of age, sex, habitat, street access, and the presence of fleas on OE were evaluated. Cytological evidence of OE was observed in 25.5 % of cats and was statistically associated with flea and mite parasitism. Otodectes cynotis was found in 13.9 % of the cats. Cocci and Bacilli were the secondary factors in 34.3 % and 22.9 % of cats with OE, respectively. The Malassezia genus was a secundary factor in 57.1 % of the cats with OE. The frequency of OE was high in cats receiving hospital care. O. cynotis was a frequent primary cause of OE in cats. The curette sampling method is a great option for diagnosing O. cynotis infestation due to its ease of use.

High α-diversity of skin microbiome and mycobiome in Japanese patients with vitiligo.

BACKGROUND: Vitiligo is an acquired pigmentary disorder characterized by depigmented patches on the skin that majorly impact patients' quality of life. Although its etiology involves genetic and environmental factors, the role of microorganisms as environmental factors in vitiligo pathology remains under-researched. OBJECTIVES: Our study explored the presence of characteristic bacterial and fungal flora in vitiligo-affected skin and investigated their potential roles in vitiligo pathogenesis. METHODS: We sequenced bacterial 16S rRNA and the fungal ITS1 region from skin swabs collected at frequently affected sites, namely the forehead and back, of patients with vitiligo. We analyzed bacterial and fungal flora in lesional and non-lesional areas of patients with vitiligo compared with corresponding sites in age- and sex-matched healthy subjects. RESULTS: Our findings revealed elevated α-diversity in both bacterial and fungal flora within vitiligo lesions compared with healthy controls. Notably, bacterial flora exhibited a distinctive composition in patients with vitiligo, and the proportional representation of Enterococcus was inversely correlated with the degree of vitiligo progression. Gammaproteobacteria, Staphylococcus spp., and Corynebacterium spp. were more abundant in vitiligo patients, with notable Staphylococcus spp. prevalence during the stable phase on the forehead. Conversely, the proportion of Malassezia sympodialis was lower and that of Malassezia globosa was higher in the progressive phase on the back of vitiligo patients. CONCLUSION: Our study identified some characteristic bacterial and fungal groups associated with vitiligo activity and prognosis, highlighting the potential roles of microorganisms in pathogenesis and offering insights into personalized disease-management approaches.

Presence of Malassezia Hyphae Is Correlated with Pathogenesis of Seborrheic Dermatitis.

Seborrheic dermatitis (SD) is a common, chronic, and relapsing skin disease. The roles of Malassezia spp. in the pathogenesis of SD are still not clear due to the lack of direct evidence for the existence of hyphae within affected skin tissues. We set out to elucidate if Malassezia mycelium contributes to the onset and development of SD and if Malassezia mycelium is correlated with the clinical severity of SD patients. We detected Malassezia hyphae in patients with SD using potassium hydroxide (KOH) and calcofluor white (CFW) staining. Fluorescent microscopy was performed for the analysis of fungal cell wall and morphological characteristics of Malassezia under CFW staining. Culture growth in modified Dixon agar was used for DNA extraction and sequencing, and Malassezia species were confirmed by a sequencing data BLAST search against the NCBI database. We demonstrated that Malassezia hyphae were positively correlated with the clinical severity of SD patients (P = 3.1738 × 10-11). All the patients responded well to antifungal treatment. There is no significant difference for species dominance across the variant groups. However, the exact molecular mechanisms of how Malassezia spp. affect SD need to be further explored. The results show that Malassezia spp. in the hyphal stage are restricted to SD patients compared with healthy controls, suggesting that the presence of Malassezia hyphae contributes to the pathogenesis of SD. The results highlight the importance of the antifungal therapy for the future treatment of SD patients. IMPORTANCE Our results support the proposal that the hyphal form of Malassezia could be one of the pathogenic factors that contribute to SD, which has been previously less well studied. This clinical observation paves the way for further investigations of the molecular mechanisms of Malassezia hyphal pathogenicity in SD.

Comparison of virulence factors and susceptibility profiles of Malassezia furfur from pityriasis versicolor patients and bloodstream infections of preterm infants.

In spite of the increasing medical interest in Malassezia yeasts, the virulence factors of Malassezia furfur causing bloodstream infections (BSI) were never investigated. Therefore, phospholipase (Pz), lipase (Lz), hemolysin (Hz), biofilm production, and in vitro antifungal susceptibility profiles were evaluated in M. furfur strains, isolated from both pityriasis versicolor (PV) patients (n = 18; Group 1) or from preterm infants BSI (n = 21; Group 2). All the test stains exhibited Pz activity, whereas 92.3% and 97.4% of strains exhibited Lz and Hz activities, respectively. Pz, Lz, and Hz activities were higher (i.e., lower values) within Group 1 strains (i.e., 0.48, 0.40, and 0.77) than those within Group 2 (i.e., 0.54, 0.54, and 0.81). The biofilm production was higher within Malassezia isolates from Group 2 (0.95 ± 0.3) than from Group 1 (0.72 ± 0.4). Itraconazole and posaconazole were the most active drugs against M. furfur, followed by amphotericin B and fluconazole. The minimum inhibitory concentrations (MIC) values varied according to the origin of M. furfur strains being statistically lower in M. furfur from Group 1 than from Group 2. This study suggests that M. furfur strains produce hydrolytic enzymes and biofilm when causing PV and BSI. Data show that the phospholipase activity, biofilm production, and a reduced antifungal susceptibility profile might favor M. furfur BSI, whereas lipase and hemolytic activities might display a synergic role in skin infection.

There is no information on the virulence factors of M. furfur involved in invasive infections. Our data suggest that the phospholipase activity, biofilm production, and a reduced antifungal susceptibility profile might favor M. furfur blood-stream infections.

Pilot study of dogs with suppurative and non-suppurative Malassezia otitis: A case series.

BACKGROUND: Rarely, Malassezia otitis presents as a painful, erosive otitis with an otic discharge containing Malassezia and neutrophils on cytology. There are no published reports of this type of suppurative Malassezia otitis (SMO). The role of Malassezia hypersensitivity in otitis is still unknown, and no association has been demonstrated with SMO. We compared Malassezia IgE levels, intradermal test and histology changes in SMO dogs with the more conventional Malassezia otitis (MO) presentation. RESULTS: Three dogs (case 1, case 2 and case 3) were diagnosed with SMO, one dog (case 4) was diagnosed with unilateral MO and unilateral SMO, and one dog (case 5) was diagnosed with MO. Only one case (case 4) with SMO/MO had a positive Intradermal Allergy Test (IDAT) and elevated IgE levels for Malassezia. Histopathology findings from SMO revealed: interface dermatitis (case 1 and 3), lymphocytic dermatitis (case 2) and chronic hyperplastic eosinophilic and lymphoplasmacytic dermatitis (case 4). Histopathology findings from MO showed perivascular dermatitis (case 4 and 5). All the cases were treated successfully. CONCLUSIONS: SMO presents with a distinct clinical phenotype in comparison with conventional MO. No consistent aetiology could be isolated. In these clinical cases it is possible that previous treatments could have influenced the results. More research is needed to understand the possible aetiologies and the pathogenesis of SMO.

Prevalence and in vitro antifungal susceptibility of commensal yeasts in the external ear canal of cats.

BACKGROUND: Lifestyle factors such as hair length, the frequency of ear cleaning and bathing, age, cat rearing, and sex may contribute to opportunistic yeast infections in the external ear canal of cats. This study aimed to determine the prevalence of commensal yeast organisms in cats' external ear canals, evaluate their predisposing lifestyle factors, and test the susceptibility of Malassezia pachydermatis to antifungal agents. RESULTS: A total of 53 cats (33 male and 20 female) seronegative for feline leukemia virus and feline immunodeficiency virus were enrolled in this study. Their mean age (± standard deviation) was 6.04 (± 3.49) years. Fungal cultures and polymerase chain reaction tests were performed to identify the yeast species derived from the external ear canal. The association between lifestyle factors and the presence of M. pachydermatis was evaluated using Fisher's exact test. The susceptibility of M. pachydermatis to antifungal agents was also analyzed. M. pachydermatis was the most frequently recovered yeast species, with a prevalence of 50.94 % (95 % confidence interval [CI]: 36.84-64.94 %). There was an association between hair length and a positive culture for M. pachydermatis (p = 0.0001). The odds of a negative culture for M. pachydermatis among short-haired cats was 11.67 (95 % CI, 3.22-42.24) times higher than that among long-haired cats (p = 0.0002). There was also an association between the frequency of ear cleaning and the presence of M. pachydermatis (p = 0.007). The odds of a negative culture for M. pachydermatis in cats that were receiving ear cleaning at intervals of ≤ 2 weeks was 5.78 (95 % CI, 1.67-19.94) times greater than that of cats receiving ear cleaning at intervals greater than 2 weeks or never (p = 0.0055). Ranges of minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations for itraconazole, ketoconazole, miconazole, and terbinafine against M. pachydermatis were ≤ 0.063-4 and ≤ 0.063-≥32, ≤ 0.063-8 and 0.125-≥32, ≤ 0.063-≥32 and 0.5-≥32, and ≤ 0.016-1 and 0.125-8 µg/ml, respectively. CONCLUSIONS: M. pachydermatis was the most commonly identified yeast organism in the external ear canal of healthy cats. Hair length and the frequency of ear cleaning played a role in the colonization of M. pachydermatis. The M. pachydermatis isolates had various MIC levels for common fungicides.

Composition of cutaneous bacterial microbiome in seborrheic dermatitis patients: A cross-sectional study.

BACKGROUND: Seborrheic dermatitis (SD) is a chronic inflammatory skin disease with a multifactorial aetiology. Malassezia yeasts have been associated with the disease but the role of bacterial composition in SD has not been thoroughly investigated. OBJECTIVES: To profile the bacterial microbiome of SD patients and compare this with the microbiome of individuals with no inflammatory skin disease (controls). METHODS: This was a cross sectional study embedded in a population-based study. Skin swabs were taken from naso-labial fold from patients with seborrheic dermatitis (lesional skin: n = 22; non-lesional skin SD: n = 75) and controls (n = 465). Sample collection began in 2016 at the research facility and is still ongoing. Shannon and Chao1 α- diversity metrics were calculated per group. Associations between the microbiome composition of cases and controls was calculated using multivariate statistics (permANOVA) and univariate statistics. RESULTS: We found an increased α-diversity between SD lesional cases versus controls (Shannon diversity: Kruskal-Wallis rank sum: Chi-squared: 19.06; global p-value = 7.7x10-5). Multivariate statistical analysis showed significant associations in microbiome composition when comparing lesional SD skin to controls (p-value = 0.03;R2 = 0.1%). Seven out of 13 amplicon sequence variants (ASVs) that were significantly different between controls and lesional cases were members of the genus Staphylococcus, most of which showed increased composition in lesional cases, and were closely related to S. capitis S. caprae and S. epidermidis. CONCLUSION: Microbiome composition differs in patients with seborrheic dermatitis and individuals without diseases. Differences were mainly found in the genus Staphylococcus.

Reproducing the scalp microbiota community: co-colonization of a 3D reconstructed human epidermis with C. acnes and M. restricta.

OBJECTIVE: A 3D reconstructed human epidermis (RHE) model colonized with specific microbial strains was developed to model the complex interactions between strains of the human scalp hair. METHODS: Reconstructed human epidermis was colonized with Cutibacterium acnes and Malassezia restricta for 72 h. The epidermal model was characterized in terms of morphology, using immune-labelling targeting biomarkers for barrier structure, proliferation, differentiation and anti-microbial defence. The barrier function was assessed by transepithelial electrical eesistance (TEER) measurements. In order to study the microorganisms on the epidermal model, viable counts and phenotype ultrastructure analysis were performed by scanning electron microscopy (SEM). RESULTS: The RHE colonized with C. acnes did not lead to severe modifications of the physiological barrier integrity and viability, though it shows aggregates. M. restricta formed large aggregates by a close interaction with the RHE, thus causing both a strong decrease in barrier function and structure degradation and an increased human beta defensin 2 (HBD2) expression. The co-colonized model resulted in barrier depletion, but the overall damage was less severe, respecting the single colonization with M. restricta. The developed 'scalp model' allowed to identify morphological modifications leading to uncontrolled epidermal renewal. CONCLUSION: This study shows a pre-clinical model that recapitulates the interactions that can occur between site-specific microbial strains and keratinocytes in dandruff condition. The model can be applied to assess ingredients and products' mechanism of action.

OBJECTIF: Un modèle d'épiderme humain reconstruit a été colonisé par des souches microbiennes spécifiques du cuir chevelu pour étudier les interactions complexes entre les microorganismes et l'épiderme. MÉTHODES: Les épidermes humains reconstruits ont été colonisés par Cutibacterium acnes et Malassezia restricta pendant 72 h, puis caractérisés morphologiquement et par immunomarquages pour suivre les marqueurs de la différenciation kératinocytaire pour la fonction barrière, de prolifération et de défense antimicrobienne. La fonction barrière a également été évaluée par des mesures de résistance électrique transépithéliale (TEER). Afin d'étudier les microorganismes sur le modèle épidermique, des numérations des microorganismes viables et une analyse de l'ultrastructure phénotypique par microscopie électronique à balayage ont été effectuées. RÉSULTATS: Les modèles colonisés par C. acnes n'ont pas conduit à des modifications conséquentes de l'intégrité et de la viabilité de la barrière physiologique, bien que cette souche forme des agrégats. M. restricta a formé de gros agrégats par une interaction étroite avec l'épiderme, provoquant ainsi à la fois une forte diminution de la fonction barrière, une dégradation de la structure et une augmentation de l'expression de la bêta-défensine 2 humaine. Les modèles co-colonisés ont montré une altération de la fonction barrière, mais les dommages globaux étaient moins drastiques que lors de la simple colonisation par M. restricta. Ce « modèle de cuir chevelu ¼ développé a permis d'identifier des modifications morphologiques conduisant à un renouvellement épidermique incontrôle. CONCLUSION: Cette étude propose un modèle préclinique qui mime les interactions qui peuvent se produire entre les souches microbiennes spécifiques de ce site anatomique et les kératinocytes du scalp en condition pelliculaire. De plus, ce modèle peut être utiliser pour screener ingrédients et produits formulés et ainsi accéder à leurs mécanismes d'action.

Sociodemographic characteristics and spectrum of Malassezia species in individuals with and without seborrhoeic dermatitis/dandruff: A comparison of residents of the urban and rural populations.

Seborrhoeic dermatitis/dandruff (SD/D) is a common, persistent, relapsing inflammatory condition affecting the areas rich in sebaceous glands. SD/D is widely prevalent in India but Malassezia species implicated are not well studied. To estimate the prevalence and spectrum of Malassezia species causing SD/D and understand the sociodemographic characteristics of SD/D in rural and urban populations, a total of 200 SD/D patients and 100 healthy controls (HC) from both rural and urban backgrounds were enrolled in this study. SD/D severity was clinically graded as mild, moderate, severe, and very severe. The isolates were identified by phenotypic characters and confirmed by ITS2 PCR-RFLP and sequencing of the ITS region of rDNA. Severe (59%) and very severe (71%) form of SD/D was higher in the rural population compared to the urban population (P = .004). The isolation rate of Malassezia was significantly higher in overall SD/D patients scalp (82%) compared to HC (67%) (P = .005). From the scalp of SD/D patients, M. globosa (36.2%) was predominantly isolated followed by M. restricta (31.3%), M. furfur (15.7%), a mixture of M. globosa and M. restricta (12%) or M. arunalokei (4.8%). Similarly, M. globosa (49.3%) was predominately isolated from the scalp of HC followed by M. restricta (22.4%). M. restricta was significantly higher in the scalp of SD/D patients compared to HC and/or nasolabial fold of both SD/D patients and HC (P = .0001). Our findings indicate that M. restricta has a high association with SD/D. More severe disease frequency was observed in the rural population. PRECIS: Dandruff is associated with Malassezia restricta and very severe cases are higher in rural population, probably due the poor hygiene. Moderate to severe hair loss and itching were strongly associated with dandruff. Use of soaps to cleanse scalp appears to be better than shampoo in preventing dandruff.

Malassezia and Staphylococcus dominate scalp microbiome for seborrheic dermatitis.

Seborrheic dermatitis (SD) is a common disease of the human scalp that causes physical damage and psychological problems for patients. Studies have indicated that dysbiosis of the scalp microbiome results in SD. However, the specific fungal and bacterial microbiome changes related to SD remain elusive. To further investigate the fungal and bacterial microbiome changes associated with SD, we recruited 57 SD patients and 53 healthy individuals and explored their scalp microbiomes using next generation sequencing and the QIIME and LEfSe bioinformatics tools. Skin pH, sebum secretion, hydration, and trans-epidermal water loss (TWEL) were also measured at the scalp. We found no statistically significant differences between the normal and lesion sites in SD patients with different subtypes of dandruff and erythema. However, the fungal and bacterial microbiome could differentiate SD patients from healthy controls. The presence of Malassezia and Aspergillus was both found to be potential fungal biomarkers for SD, while Staphylococcus and Pseudomonas were found to be potential bacterial biomarkers. The fungal and bacterial microbiome were divided into three clusters through co-abundance analysis and their correlations with host factors indicated the interactions and potential cooperation and resistance between microbe communities and host. Our research showed the skin microbe dysbiosis of SD and highlighted specific microorganisms that may serve as potential biomarkers of SD. The etiology of SD is multi-pathogenetic-dependent on the linkage of several microbes with host. Scalp microbiome homeostasis could be a promising new target in the risk assessment, prevention, and treatment of SD disease.

The skin mycobiome of an astronaut during a 1-year stay on the International Space Station.

Analysis of the skin mycobiome of an astronaut during a 1-year stay on the International Space Station (ISS) revealed an increased relative abundance of Malassezia restricta and level of Malassezia colonization, and the presence of Cyberlindnera jadinii and Candida boidinii, uncommon skin mycobiome taxa. Similar observations were made in astronauts during a 6-month stay on the ISS (Med Mycol. 2016; 54: 232-239). Future plans for extended space travel should consider the effect of high levels of Malassezia colonization over long periods on astronauts' skin, and the abnormal proliferation of uncommon microorganisms that may occur in closed environments such as the ISS.

A case of anti- pityriasis versicolor therapy that preserves healthy mycobiome.

BACKGROUND: The impact of Malassezia yeasts on skin mycobiome and health has received considerable attention recently. Pityriasis versicolor (PV), a common dermatosis caused by Malassezia genus worldwide, is a manifestation of dysbiosis. PV can be associated with hyper- and/or hypopigmented skin lesions. This disease entity is characterized by high percentage of relapses, which demands a proper antifungal therapy that is based on unambiguous species identification and drug susceptibility testing. CASE PRESENTATION: Comprehensive analysis of PV case in man presenting simultaneously hyper- and hypopigmented skin lesions was performed. Conventional and molecular diagnostic procedures revealed Malassezia furfur and Malassezia sympodialis, respectively as etiological agents of skin lesions observed. Susceptibility tests showed significantly lowered sensitivity of M. furfur cells to fluconazole. Based on susceptibility profiles local antifungal therapy with drugs characterized by entirely different mechanism of action was included. CONCLUSIONS: Our study indicates that cases of PV represented by two types of skin lesions in one patient may be associated with distinct Malassezia species. Moreover, as observed in this case, each of the isolated etiological agents of PV may differ significantly in susceptibility to antifungals. This can significantly complicate the treatment of dermatosis, which by definition is associated with a significant percentage of relapses. In the presented case localized topical treatment was sufficient and successful while allowing maintaining the physiological mycobiome.

Malassezia Hepatic Abscess in a Neonate.

Malassezia sp. require exogenous lipid for growth and can cause disseminated infection in neonates requiring intravenous lipid infusions. Usually, Malassezia infection in neonates presents as fungemia or hematogenous dissemination into bone or lungs. We present a presumed case of Malassezia liver abscess associated with lipid infusion via a mispositioned umbilical venous catheter.

Use of whole-genome sequencing to detect an outbreak of Malassezia pachydermatis infection and colonization in a neonatal intensive care unit-California, 2015-2016.

Whole-genome sequencing confirmed the presence of a Malassezia pachydermatis outbreak among neonates in a neonatal intensive care unit. This technology supports the importance of adhering to infection prevention measures.