Dermatophytosis in Small Animals Antonella S
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www.symbiosisonline.org Symbiosis www.symbiosisonlinepublishing.com Review Article SOJ Microbiology & Infectious Diseases Open Access Dermatophytosis in Small Animals Antonella S. Mattei1*, Márcia A. Beber2 and Isabel M. Madrid3 1University Federal of Rio Grande (FURG), Medical School, RS, Brazil 2Undergraduate Student in Dentistry, Federal University of Pelotas (UFPel), Pelotas, RS, Brazil 3Facuty of Veterinary, Zoonosis Center Control, Federal University of Pelotas (UFPel), Pelotas, RS, Brazil Received: March 06, 2014; Accepted: September 19, 2014; Published: November 04, 2014 *Corresponding author: Antonella Souza Mattei, University Federal of Rio Grande (FURG), Medical School, RS, Brazil, Tel: +55(53)-91447884; E-mail: an- [email protected] Originally soil inhabitants, dermatophytes have evolved to Abstract geophilic, zoophilic, and anthropophilic species based on their dermatophytosis in small animals. In the last years, the pet population maininfect habitatanimals or and host. humans Three dermatophytes and are accordingly genera classified Trichophyton into, has increasedThe purpose as well of the this interest article in havingwas animalsto briefly as pets.review Because about of Microsporum, and Epidermophyton-comprise more than 40 this, these small animals are more and more inserted in our daily life. different species [4,5]. The understanding of ringworm epidemiology, diagnosis, treatment and control in pets is very important for the reason that pets are often Animals can be infected by a great variety of dermatophytes, asymptomatic carriers of dermatophytes being important sources of mostly zoophilic but also geophilic species, and exceptionally infection and/or carriers of infection. So, it is very important to know about this disease to reduce the spread of zoophilic fungal infections anthropophilic dermatophytes (Table 1) [6]. in humans, considering the close contact between pets and their Clinical importance is usually mild except in heavily infected owners, especially between children and their pets. young animals such as calves with an impact on general health Keywords: Cat; Dog; Exotic pet mammals; Microsporum spp.; condition and growth. On the contrary, serious economic Trichophyton spp.; Zoonosis; Dermatophytosis; Mycosis consequences result from the long duration of the disease [1,6]. The understanding of ringworm epidemiology, diagnosis, Abbreviations treatment and control in pets is very important for reducing the spread of fungal infections in animals and humans. The purpose FeLV: Feline Leukemia Virus; Virus; KOH: Potassium Hydroxide; Min: Minutes FIV: Feline Immunodeficiency small animals. Introduction of this article was to briefly review about dermatophytosis in In recent years, both the number of domestic pets fed Table 1: Zoophilic and Geophilic dermatophytes species in animals. inside their owners’ homes and the interest in having animals Dermatophytes species Main source Others as pets at one’s home have increased markedly. Considering Microsporum canis Cat, dog, horse All mammals the close contact between pets and their owners, especially Microsporum gallinae poultry Dog, cat between children and cats and dogs, these animals that are Microsporum gypseum Soil All mammals often asymptomatic carriers of dermatophytes can be important sources of infection and/or carriers of infection [1]. Microsporumn nanum Soil Pig Microsporum persicolor Microtid rodents Dog, cat However, nowadays not only cats and dogs are popular pets, the exotic companion mammals (e.g. rabbits, rodents, ferrets, Trichophyton equinum Horse Cat, dog (rare) hedge hogs) are also common and they can be a potential source Trichophyton erinacei Hedgehog Dog of zoonotic infections transmissible to their owners [2]. Trichophyton Rodents All mammals mentagrophytes Trichophyton simii Primate Fowl, dog, cat Dermatophytosis is characterized by a superficial skin Cattle, other fungal disease in clinical veterinary medicine in small animals. Trichophyton verrucosum All mammals Theseinfection fungi confined produce to keratinisedkeratinases epithelium,and others isenzymes the most capable common to ruminants digest the keratin protein complex, allowing the dermatophyte Note: Other geophilic species are frequently isolated from hair coat of M. to burrow deeper into the stratum corneum in the host and cookei, M. praecox (frequent in the equine environment and sometimes pathogenicmammals, but,for man),usually, T. withoutajelloi, T.pathogenic terrestre. Somesignificance rare cases in animals: of animal ringworm due to anthropophilic dermatophytes (E. floccosum, T. rubrum therefore to elicit an inflammatory reaction. The,4]. degree of and T. tonsurans in dog; T. violaceum in pig) have been reported. inflammation, dependent of host-fungus interaction, determines the degree and significance of the clinical signs [3 Symbiosis Group *Corresponding author email: [email protected] Dermatophytosis in Small Animals Copyright: © 2014 Mattei et al. Etiology three genera, Epidermophyton, Microsporum, and Trichophyton [4,7].The The etiologic descriptions agents of thethe dermatophytoses genera are essentially are classified followed in by the colony macroscopic aspects (diameter, texture, surface color and reverse color) and themicroscopic aspects (conidial morphology and formation of conidia). They both are updated following the discovery of new species. The genera and their descriptions are as follows: 1A) 1B) Epidermophyton spp: The type species is Epidermophyton Figure 1: Microsporum canis culture, macroscopic colony (A) and mi- floccosum croscopic observation in lactophenol (B) (Veterinary Mycology Labora- turning into powder surface, central poor radial grooves and tory, MICVET, Federal University of Pelotas, Rio Grande do Sul, Brazil). white color(Figure turning 1A intoand B).yellow-green The colony oraspects mustard-yellow are filamentous and brown-yellow reverse in Sabouraud dextrose agar at 25°C. The macroconidia are broadly clavate with typically smooth, thin to moderately thick walls and one to nine septa, 20 to 60 by 4 to clusters. Microconidia are absent. This genus has only two known species13 mm into size.date, They and only are usuallyE. floccosum abundant is pathogenic and borne [7-11]. singly or in Microsporum spp: The type species is Microsporum canis (Figure 2A and B). The colony aspects are plane, velvety or cottony surface, white or yellowish color and brown or golden- 2A) 2B) yellow reverse in Sabouraud dextrose agar at 25°C. Macroconidia are characterized by the presence of rough walls which may be Figure 2: Microsporum gypseum culture, macroscopic colony (A) and asperulate, echinulate, or verrucose. They are fusiform, obovate microscopic observation in lactophenol (B) (Veterinary Mycology Labo- (egg shaped) or cylindrofusiform. They may also have thin, ratory, MICVET, Federal University of Pelotas, Rio Grande do Sul, Bra- zil). moderately thick to thick walls and 1 to 15 septa and range in size from 6 to 160 by 6 to 25 mm. Microconidia are sessile or stalked and clavate and usually arranged singly along the hyphae or in racemes [7-11]. Trichophyton spp: The type species is Trichophyton mentagrophytes var. Mentagrophytes . The colony aspects are plane, white to cream color, powdery to granular surface and reverse yellowish(Figure brown to3A reddish-brown and B) in Sabouraud dextrose agar at 25°C. Macroconidia, when present, have smooth, usually thin walls and one to 12 septa, are borne singly or in clusters, and may be elongate and pencil shaped, 3A) 3B) clavate, fusiform, or cylindrical. They range in size from 8 to Figure 3: Trichophyton mentagrophytes var. mentagrophytes culture, 86 by 4 to 14 mm. Microconidia, usually more abundant than macroscopic colony (A) and microscopic observation in lactophenol (B) macroconidia, may be globose, pyriform or clavate, or sessile or (Veterinary Mycology Laboratory, MICVET, Federal University of Pelo- stalked, and are borne singly along the sides of the hyphae or in tas, Rio Grande do Sul, Brazil). grape-like clusters [7-11]. In 1999, the Trichophyton tonsurans, T. mentagrophytes There are genotypic and phenotypic variations between isolates of the same species of dermatophyte. The clinical taxa, T. tonsurans, T. interdigitale (anamorph of Arthoderma application of these variations has to be discovered yet. These vanbreuseghemiiand related species), T. mentagrophytes,and varieties wereT. simii reclassified (anamorph into of A.5 simii) and T. erinacei (anamorph of A. benhamiae). In 2007, this was epidemiological data [14]. variations do not reflect differences in symptomatology or chaged by treating T. mentagrophytes as the anamorph of A. simii The fungal pathogenicity factors, such as enzyme production, in place of T. simii and adding another anamorph of A. benhamiae, were associated with different clinical dermatophytosis pictures. Trichophyton spp. Furthermore, in 2010 T. mentagrophytes was Apparently, studies examining the enzyme production through replaced by T. simii and treated again as an individual species, i.e. molecular characterization and expression during infection are T. mentagrophytes var. quinckeanum [12]. an importante means to understand the details of pathogenicity Nowadays, the three genera, Epidermophyton, Microsporum, and may also answer questions related to the different degrees of and Trichophyton, virulence observed in different hosts [14-17]. On the basis of dermatophyte primary habitat associations, can be identified based on molecular taxonomic