真菌是影响动物皮肤的最常见的传染因子之一。皮肤可以作为真菌感染的入口,最终会被传播。在世界的一些地区,卵菌,如Pythium和Lagenium,也是造成大量严重皮肤感染的原因。真菌形态学的组织学评估,包括尺寸,形状,隔膜,分支,和萌芽特征,结合不同皮肤层内炎症浸润的分布,可以潜在地确定病因,指导抗真菌药和其他诊断的选择。皮肤表面的真菌感染通常是由马拉色菌引起的,很少是念珠菌。机会性真菌也能够在皮肤表面定殖,尤其是当屏障被打破时。Folliculocentric感染,由皮肤癣菌引起的,导致轻度至重度炎症,偶尔会深入皮肤。种类繁多的真菌,包括口疮真菌病,phaeophyphysp真菌病,和双态真菌感染,以及卵菌,导致皮肤和皮下结节性病变。偶尔除了双态真菌,真菌物种形成通常需要在新鲜组织上进行培养。然而,分子技术,例如石蜡块上的泛真菌聚合酶链反应,正成为区分皮肤真菌病原体的越来越有用的工具。这篇综述着重于描述影响动物皮肤的最常见真菌和卵菌感染的临床和组织学特征,根据病变的分布模式和真菌或卵菌的形态进行划分。
Fungi are among the most common infectious agents affecting the skin of animals. The skin can serve as a port of entry for fungal infections, which can eventually become disseminated. In some regions of the world, oomycetes, such as Pythium and Lagenidium, are also responsible for a significant number of severe cutaneous infections. Histologic evaluation of fungal morphology, including size, shape, septation, branching, and budding characteristics, combined with the distribution of inflammatory infiltrates within different skin layers can potentially identify etiologic agents, guiding selection of antifungals and additional diagnostics. Fungal infections of the skin surface are typically caused by Malassezia and rarely Candida, with opportunistic fungi also capable of colonizing the skin surface, especially when the barrier is broken. Folliculocentric infections, caused by dermatophytes, result in mild to severe inflammation and can occasionally penetrate deep into the skin. A wide range of fungi, including agents of hyalohyphomycosis, phaeohyphomycosis, and dimorphic fungal infections, as well as oomycetes, result in nodular cutaneous and subcutaneous lesions. With the occasional exception of dimorphic fungi, fungal speciation often requires cultures performed on fresh tissues. However, molecular techniques such as pan-fungal polymerase chain reaction on paraffin blocks is becoming an increasingly useful tool to distinguish between cutaneous fungal pathogens. This
review focuses on describing the clinical and histologic features of the most common fungal and oomycete infections affecting the skin of animals, divided according to distribution patterns of lesions and fungal or oomycete morphology.