Zaias N, Escovar S X, Zaiac M N
Dermatology Mt. Sinai Medical Center, Miami Beach, Florida.
J Eur Acad Dermatol Venereol. 2015 May;29(5):848-53. doi: 10.1111/jdv.12862. Epub 2014 Dec 16.
Onycholysis - the separation of the nail plate from the nail bed occurs in fingers and toenails. It is diagnosed by the whitish appearance of the separated nail plate from the nail bed. In fingers, the majority is caused by trauma, manicuring, occupational or self-induced behavior. The most common disease producing fingernail onycholysis is psoriasis and pustular psoriasis. Phototoxic dermatitis, due to drugs can also produce finger onycholysis. Once the separation occurs, the environmental flora sets up temporary colonization in the available space. Finger onycholysis is most common in women. Candida albicans is often recovered from the onycholytic space. Many reports, want to associate the yeast as cause and effect, but the data are lacking and the treatment of the candida does not improve finger onycholysis. A reasonable explanation for the frequent isolation of Candida and Pseudomonas in fingernail onycholysis in women, is the close proximity the fingers have to the vaginal and gastrointestinal tract. Fifty per cent of humans harbour C. albicans in the GI tract and it is frequently carried to the vagina during hygienic practices. Finger onycholysis is best treated by drying the nail 'lytic' area with a hair blower, since all colonizing biota are moisture loving and perish in a dry environment. Toenail onycholysis has a very different etiology. It is mechanical, the result of pressure on the toes from the closed shoes, while walking, because of the ubiquitous uneven flat feet producing an asymmetric gait with more pressure on the foot with the flatter sole.
甲剥离——指甲板与甲床分离，可发生于手指和脚趾的指甲。通过观察分离的指甲板与甲床呈现白色外观来诊断。在手指上，多数情况是由外伤、修甲、职业因素或自我诱发行为引起。导致手指甲甲剥离最常见的疾病是银屑病和脓疱型银屑病。药物引起的光毒性皮炎也可导致手指甲剥离。一旦发生分离，环境中的微生物会在这个空间暂时定植。手指甲剥离在女性中最为常见。白色念珠菌常从甲剥离的空间中检出。许多报告试图将这种酵母菌与病因联系起来，但缺乏相关数据，而且治疗念珠菌并不能改善手指甲剥离的情况。对于女性指甲甲剥离中频繁分离出念珠菌和铜绿假单胞菌的一个合理的解释是，手指与阴道和胃肠道距离很近。50%的人胃肠道中携带白色念珠菌，在卫生习惯过程中它经常会传播到阴道。手指甲剥离最好的治疗方法是用吹风机吹干指甲“剥离”区域，因为所有定植的生物群落都喜欢潮湿，在干燥环境中会死亡。脚趾甲剥离的病因则大不相同。它是机械性的，是由于行走时封闭的鞋子对脚趾施加压力所致，这是因为普遍存在的扁平足不平坦，导致不对称步态，使鞋底较平的那只脚承受更大压力。
