Chabasse D, Pihet M
Institut de biologie en santé, laboratoire de parasitologie-mycologie, centre hospitalier universitaire, 4, rue Larrey, 49933 Angers cedex 9, France.
Institut de biologie en santé, laboratoire de parasitologie-mycologie, centre hospitalier universitaire, 4, rue Larrey, 49933 Angers cedex 9, France.
J Mycol Med. 2014 Dec;24(4):261-8. doi: 10.1016/j.mycmed.2014.10.005. Epub 2014 Nov 20.
Onychomycoses represent about 30% of superficial mycosis that are encountered in Dermatology consults. Fungi such as dermatophytes, which are mainly found on the feet nails, cause nearly 50% of these onychopathies. Yeasts are predominantly present on hands, whereas non-dermatophytic moulds are very seldom involved in both foot and hand nails infections. According to literature, these moulds are responsible for 2 to 17% of onychomycoses. Nevertheless, we have to differentiate between onychomycoses due to pseudodermatophytes such as Neoscytalidium (ex-Scytalidium) and Onychocola canadensis, which present a high affinity for keratin, and onychomycoses due to filamentous fungi such as Aspergillus, Fusarium, Scopulariopsis, Acremonium... These saprophytic moulds are indeed most of the time considered as colonizers rather than real pathogens agents. Mycology and histopathology laboratories play an important role. They allow to identify the species that is involved in nail infection, but also to confirm parasitism by the fungus in the infected nails. Indeed, before attributing any pathogenic role to non-dermatophytic moulds, it is essential to precisely evaluate their pathogenicity through samples and accurate mycological and/or histological analysis. The treatment of onychomycoses due to non-dermatophytic moulds is difficult, as there is today no consensus. The choice of an antifungal agent will first depend on the species that is involved in the infection, but also on the severity of nail lesions and on the patient himself. In most cases, the onychomycosis will be cured with chemical or mechanical removing of the infected tissues, followed by a local antifungal treatment. In some cases, a systemic therapy will be discussed.
甲真菌病约占皮肤科门诊中浅表真菌病的30%。皮肤癣菌等真菌主要见于趾甲，导致近50%的这些甲病。酵母菌主要见于手部，而非皮肤癣菌性霉菌很少累及趾甲和指甲感染。根据文献，这些霉菌导致2%至17%的甲真菌病。然而，我们必须区分由对角蛋白具有高度亲和力的假皮肤癣菌如新型隐球酵母（原称赛多孢酵母）和加拿大甲癣菌引起的甲真菌病，以及由丝状真菌如曲霉菌、镰刀菌、帚霉、枝顶孢霉……引起的甲真菌病。实际上，这些腐生霉菌大多数时候被视为定植菌而非真正的病原体。真菌学和组织病理学实验室发挥着重要作用。它们不仅能识别涉及指甲感染的菌种，还能通过对感染指甲的真菌进行检查以确认是否存在寄生现象。的确，在将任何致病作用归因于非皮肤癣菌性霉菌之前，通过样本以及准确的真菌学和/或组织学分析精确评估其致病性至关重要。由于目前尚无共识，治疗由非皮肤癣菌性霉菌引起的甲真菌病很困难。抗真菌药物的选择首先取决于感染涉及的菌种，还取决于指甲病变的严重程度以及患者自身情况。在大多数情况下，通过化学或机械方法去除感染组织，随后进行局部抗真菌治疗，甲真菌病可治愈。在某些情况下，则会考虑全身治疗。
