Daniel Ralph, Meir Babaev, Avner Shemer
Private Practice Dermatology Clinic, Jackson, MS, USA.
Skin Appendage Disord. 2017 Mar;3(1):15-17. doi: 10.1159/000455013. Epub 2017 Jan 6.
The nail bed may epithelialize and develop dermatoglyphics after long-standing onycholysis. We have called this phenomenon the disappearing nail bed (DNB). DNB may present as a shortened or narrow nail bed.
Examination of all 20 nails was performed in each patient enrolled to the study. DNB was defined as the presence of a nail which is at least 20% shorter and/or narrower than the identical nail on the opposite hand or foot. Age, sex, and nail history were recorded. Fungal studies were done on all patients with DNB if that nail exhibited clinical signs of onychomycosis.
Of 540 patients, 71 (13.15%) showed DNB. Sixty patients had only the toenails involved, and 10 patients had only the fingernails involved. One patient had both toenails and fingernails involved. The average age for fingernail DNB was 67.2 years and 69.6 years for toenails DNB. Nail history was remarkable for biting in 8 patients, nail trauma in 11 patients, and surgery in 12 patients. With respect to the toenails, onychomycosis was found in 22 patients of the DNB group.
Our study suggests that DNB is a common phenomenon, which is more likely to appear in advancing age and is associated with onychomycosis.
长期甲剥离后，甲床可上皮化并形成皮纹。我们将此现象称为甲床消失（DNB）。DNB可表现为甲床缩短或变窄。
对纳入本研究的每位患者的20个指甲均进行检查。DNB定义为某一指甲比另一只手或脚上相同的指甲至少短20%和/或窄20%。记录年龄、性别和指甲病史。如果DNB的指甲有甲真菌病的临床体征，则对所有患者进行真菌学检查。
540例患者中，71例（13.15%）出现DNB。60例患者仅累及趾甲，10例患者仅累及指甲。1例患者的趾甲和指甲均受累。指甲DNB患者的平均年龄，指甲为67.2岁，趾甲为69.6岁。8例患者有咬甲史，11例患者有甲外伤史，12例患者有手术史。在趾甲方面，DNB组22例患者发现甲真菌病。
我们的研究表明，DNB是一种常见现象，更易出现在老年人中，且与甲真菌病有关。
