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The classical dermatophytes diagnosis is based on mycological culture and microscopy observation both human and animal hair, skin, and nail samples. The aim of this work was to develop the new in-house real-time PCR with pan-dematophyte reaction for detection and identification of the main dermatophytes directly from hair samples, providing a simple and rapid diagnosis of dermatophytosis in dogs and cats. An in-house SYBR-Green real-time PCR was designed and used for detecting a DNA fragment encoding chitin synthase 1 (CHS1). A total of 287 samples were processed by culture, microscopic examination with KOH 10%, and real-time PCR (qPCR) analysis. Melting curve analysis of the CHS1 fragment revealed to be reproducible, showing a single distinct peak for each species of dermatophyte, namely Trichophyton mentagrophytes, T. verrucosum, Microsporum canis, and Nannizzia gypsea (formerly M. gypseum). Then, out of the 287 clinically suspected cases of dermatophytosis, 50% were positive for dermatophytes by qPCR, 44% by mycological culture, and 25% by microscopic examination. Microsporum canis was identified in 117 samples tested by culture and 134 samples tested by qPCR, followed by N. gypsea in 5 samples (either tested by culture or qPCR) and T. mentagrophytes detected in 4 and 5 samples when tested by culture or qPCR, respectively. Overall, qPCR allowed the diagnosis of dermatophytosis in clinical samples. The results suggest this newly proposed in-house real-time PCR assay can be used as alternative diagnosis and rapid identification of dermatophytes frequently associated to clinical hair samples of dogs and cats., (© The Author(s) 2023. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Sporotrichosis is a disease caused by thermally dimorphic fungi belonging to the Sporothrix schenckii complex. We report the occurrence of multiple cases of sporotrichosis in cats in Porto Alegre (RS), Brazil, from 2015 to 2019. A set of 21 fungal isolates were collected and the partial sequence of calmodulin (CAL) gene compared. All isolates were identified at phenotypic and molecular level as S. brasiliensis. Phylogenetic analysis showed the isolates clustered in two distinct groups, suggesting the presence of multiple genetic variants of S. brasiliensis in the region., (© The Author(s) 2020. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Sporotrichosis is caused by species of fungi within the Sporothrix schenckii complex that infect man and animals. In Rio de Janeiro, Brazil, an epidemic has been observed since 1998, with most of the cases being related to transmission from infected cats. Although the definitive diagnosis of feline sporotrichosis is made by fungal culture, cytopathological and histopathological examinations are used routinely, because the long culture period may delay treatment onset. However, alternative methods are desirable in cases of low fungal burden. Immunohistochemistry (IHC) has been described as a sensitive method for diagnosing human and canine sporotrichosis, but there are no reports of its application to cats. The aim of this study was to analyse the sensitivity of cytopathological examination (Quick Panoptic method), histopathology (Grocott silver stain) and anti-Sporothrix IHC by blinded comparisons, using fungal culture as the reference standard. Samples were collected from 184 cats with sporotrichosis that exhibited skin ulcers. The sensitivities of Grocott silver stain, cytopathological examination and IHC were 91.3%, 87.0% and 88.6%, respectively. Grocott silver stain showed the best performance. IHC showed high sensitivity, as did cytopathological examination and these may be considered as alternative methodologies. When the three methods were combined, the diagnosis was established in 180 (97.8%) out of 184 cases. Taken together, these findings indicate the need to implement these methods as routine tools for the early diagnosis of sporotrichosis in cats, notably when fungal culture is not available., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Pseudomycetomas are deep cutaneous to subcutaneous lesions caused by Microsporum canis mainly described in Persian cats, with few reports of intra-abdominal location. This report describes the clinical signs and lesions of intra-abdominal pseudomycetomas caused by M. canis in two Persian cats., Case Report: Two Persian cats with a history of previous laparotomy (ovariohysterectomy and nephrostomy) and fecal impaction were examined. Cat #1 was euthanized and subjected to necropsy, histopathology and mycological evaluation. Cat #2 presented with chronic dermatophytosis, and an intra-abdominal mass, that was subjected to histopathology evaluation. Cat #1 presented at necropsy a white-grayish, firm mass (6cm×3.5cm×2.8cm) in the uterine cervix. Cat #2 presented a firm whitish mass (6.5cm×1.5cm×0.5cm) located close to the left kidney. Histologically, both masses contained multifocal granules with hyphae and spores surrounded by Splendore-Hoeppli reaction, with a pyogranulomatous inflammatory infiltrate and fibrous connective tissue proliferation in the periphery. Hyphae and spores exhibited marked Grocott and periodic acid-Schiff staining. M. canis was identified by fungal isolation in cat #1., Conclusions: Pseudomycetoma should be considered as a differential diagnosis in cats, especially in Persian cats presenting with an intra-abdominal mass. Entrance of the agent into the cavity can occur during laparotomy., (Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Human patients with diabetes mellitus are at increased risk of fungal infections. Diabetes mellitus has also been implicated as a predisposing factor in the establishment of fungal lung infections in cats. Two diabetic cats of different origins presented with severe acute respiratory conditions that resulted in their death. At necropsy examination there was friable, black material in the main bronchi that obstructed the bronchial lumina. Microscopical examination of the lungs revealed the presence of pneumonia, calcium oxalate crystals and a large quantity of fungal hyphae and conidial heads. Fungal infection was confirmed with Grocott's methenamine silver stain. The results of the mycology analysis were compatible with Aspergillus section Nigri., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Dermatophytosis caused by Microsporum canis is a heterogeneous disease with variable clinical manifestations. M. canis is a zoophilic dermatophyte and the most frequent fungi isolated from dogs, cats and children in Brazil. The aim of this study was to investigate the genetic variability of M. canis isolates from different animal species using two microsatellite markers, namely, McGT(13) and McGT(17), and to correlate the results with the clinical and epidemiological patient data in Brazil. The study included a global set of 102 M. canis strains, including 37 symptomatic cats, 35 asymptomatic cats, 19 human patients with tinea, 9 asymptomatic dogs and 2 symptomatic dogs. A total of 14 genotypes were identified, and 6 large populations were distinguished. There was no correlation between these multilocus genotypes and the clinical and epidemiological data, including the source, symptomatology, clinical picture, breed, age, sex, living conditions and geographic location. These results demonstrate that the use of microsatellite polymorphisms is a reliable method for the differentiation of M. canis strains. However, we were unable to demonstrate a shared clinical and epidemiological pattern among the same genotype samples., (© 2013 Blackwell Verlag GmbH.)