Involvement of dermatophytes in animal and human pathology V. Cozma, V. Mircean, C. Magdaş, T. Băguţ University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Faculty© of Veterinary by author Medicine Department of Parasitology and Parasitic Diseases ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Dermatophytoses are cosmopolitan contagious mycoses confined to cutaneous layers, caused by keratinophilic and keratinolitic fungi known as dermatophytes. • Ringworm • Tinea plus latin suffix • Tinea corporis • Tinea manuum • Tinea capitis © by author • Tinea pedis (athletes foot) • Tinea cruris (jock itch) • Tinea unguium (onychomycosis) ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Importance Worldwide spread diseases Medical: usually mild except in heavily infected young animals Economic: long duration of the disease/ cost of control measures, consequent impairments on hide and skin industry Aesthetic: © by author PublicESCMID health: contagious Online & zoonotic Lecture diseases Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Etiology Kingdom Fungi phylum Ascomycota class Euascomycetes order Onygenales family Arthrodermataceae genus Arthroderma phylum Deuteromycota class Hyphomycetes © by order author Moniliales family Moniliaceae genus Trichophyton Microsporum ESCMID Online Lecture Epidermophyton Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Etiology Dermatophyte species Main source Others Zoonosis Anamorphs Teleomorphs M. canis A. otae Cat, dog, horse All mammals + M. equinum - Horse Cat, dog + M. persicolor A. persicolor Microtid rodents Dog, cat + M. gypseum A. incurvata Soil All mammals + Microspoum M. nanum A. obtusa Soil Pig + T. mentagrophytes A. benhamiae Rodents All mammals + T. verrucosum - © by authorCattle All mammals + T. equinum - Horse Cat, dog +/- T. erinacei - Hedgehog Dog + Trichophyton T. simii A. simii Primates Fowl, dog, cat + T. ESCMIDgallinae Online- LectureBirds Library- + Involvement of dermatophytes in animal and human pathology________________________________________________________ Morphology Filamentous micetes Dimorphic micettes – in vivo – hyphaes, arthrospores - in vitro - microconidia, macroconidia, hyphaes with ornamentations, clamidospores © by author ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology 1. Descriptive epidemiology Wordwide spread diseases: one of the most frequent skin diseases of pets and livestock. Zoophilic species: M. canis, T. verrucosum, T. mentagrophytes, T. equinum, M. persicolor Anthropophilic species: E. floccosum, M. audouinii, T. tonsurans, T. violaceum, T. rubrum Geophilic species: multiply in soil as saprobes and can become parasites © by author • M. gypseum, M. nanum • M. cookei, M. praecox, T. ajelloi, T. terrestre - not usually considered as pathogens are isolated in culture from coats or skin lesions ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology 1. Descriptive epidemiology Evolution- sporadically - enzootic: catteries, herds, stables - epizootic: calves Sezonality: calves © by author ESCMID Online Lecture Library Epidemiology 2. Analytic epidemiology Sources of infection - infected animals, asymptomatic carriers - contaminated crusts, scales and hairs - high resistance of arthrospores (1-4 years) Contamination – directly - indirectly © by author ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology 2. Analytic epidemiology Host specificity • variable composition and structure of the keratins • specific requirements and enzymatic equipment of dermatophyte species • occurrence of particular genes responsible for pathogenicity • the various defence mechanisms© by developed author by the hosts ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology 2. Analytic epidemiology Receptivity – species, age, diet, health • bovines, cats, dogs, horses • contamination may be easier in longhaired animals. • birds, sheep and goat → not often infected by dermatophytes • young animals are more frequently infected by dermatophytes than adults • stronger immunity in older animals due to the multiple contacts with the fungus • hyperadrenocorticism, ©immunosuppressive by author chemotherapy (corticotherapy), feline immunodeficiency virus (FIV) , the feline leukaemia virus (FeLV), nutritional disorders, tumoral disease, stress ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology 2. Analytic epidemiology Contributing factors communities: catteries, kennels, stables, cowshed or intensive breeding units overpopulation season hunting, contact with cats,© by rodents author high resistance of the dermatophyte conidia geophilic dermatophytes → animals with outdoor contacts ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology Prevalence – Italy – cats – 24.7% – 97% M. canis – 2.6% M. gypseum – 0.2% T. mentagrophytes – dogs – 18.7% – 83% M. canis – 13% M. gypseum – 5.5% T. mentagrophytes (Mancianti et al., 2002) – France – cats – 29% – dogs – 22% (Pinard© et by al, 1987)author - Switzerland – cats –29.3% - dogs – 7.1% - guinea pigs - 38.1% (Drouot et al, 2008) – CroatiaESCMID – cats – 40.7% Online – 98.7% M. Lecture canis (Pinter Libraryet al.,1999) Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology Prevalence – Romania – cats – 46% – 98.3% M. canis – dogs – 4.7% – 80% M. canis – 13.3 % T. mentagrophytes – 6.6% M. gypseum (Mircean, 2006) USA – cats – 14.9% (61/408) – 91. 8% M. canis (Lewis et al., 1991) © by author Brazil - 9.8% in dogs - M. canis, M. gypseum (Copetti et al, 2006) ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Epidemiology Prevalence T. verrucosum – Italy – 87.7% (Papini et al., 2008) – 48.7% (Galuppi et al., 2002) – 4.5- 19% (Moretti et al., 1998) – Spain – 25% (Cabanes et al., 1997) - Romania – 10-50% (Suteu and Dulceanu, 2001) – Japan – 17.1 – 58.6% (Takatori et al., 1993) © by author ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Pathogenesis The kinetics of infectious process - keratinophilic and keratinolytic properties - limited to keratinised layers of the epidermis and cutaneous adnexae - depends on fungus/host reactions towards the dermatophyte © by author ESCMID Online Lecture Library adherence of arthrospores to corneocytes: 3 - 12 h germination: 6-24 hours (humidity, warm, maceration, excoriation) invasion and penetration of the stratum corneum penetration of keratinised external+internal root sheath © by author ESCMID Online Lecture Library infection of adiacent hair folicles Involvement of dermatophytes in animal and human pathology________________________________________________________ Pathogenesis Factors that mediate adherence of dermatophytes - carbohydrate-specific adhesins expressed on the surface of microconidia in T. rubrum (Esquenazi et al., 2004) - fibrillar projections connect fungal arthrospores to keratinocytes in T. mentagrophytes (Kaufman et al., 2007) - dermatophytic-secreted proteases are necessary for efficient adhrence (Vermout et al., 2008)© by author - subtilisin, fungalysins , and dipeptidyl-peptidases ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Pathogenesis Inflammatory response • there is an inverse relationship between the degree of inflammation and duration of disease • a dermatophyte provokes a more intense inflamatory reaction on a host to which it is not adapted than it does on its natural host • T. mentagrophytes and T. rubrum – substances that diminish cell- mediated imune response and© inhibit by stratumauthor corneum turnover (Dahl, 1993) ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Pathogenesis Adaptative immunity Humoral immunity • humoral immunity to dermatophytes is not protective • however antibodies (IgM, IgG, IgA, IgE) are detected in infected animals and humans Cell-mediated immune response • the most important immunological© bydefence author mechanism • the more characteristic cell-mediated immune response to dermatophytes is DTH • the resolution of dermatophytosis is mediated by DTH (Almeida, 2008) ESCMID Online Lecture Library Involvement of dermatophytes in animal and human pathology________________________________________________________ Clinical features General presentation of animal ringworm regular and circular alopecia