Maghfour Jalal, Kane Jennifer, Robinson-Bostom Leslie, Kawaoka John, Jellinek Nathaniel
Tulane Medical School, Tulane University, New Orleans, Louisiana, USA.
Dermatology, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA.
Skin Appendage Disord. 2021 Jan;7(1):41-45. doi: 10.1159/000510674. Epub 2020 Oct 5.
Nail pathology may reflect a wide array of localized and systemic dermatological conditions. Certain nail findings such as melanonychia can create diagnostic challenges even to nail experts. We report a case of a 78-year-old man who presented with melanonychia of the great toe. Nail clipping showed focal melanin deposition, and dermoscopy demonstrated a region of localized erythema in the lunula concerning for possible melanocytic neoplasm. Subsequent nail biopsy showed numerous vertically oriented filamentous bacteria and coccobacilli within the nail plate consistent with a diagnosis of subungual nail erythrasma. Nail erythrasma is a rare entity. Additionally, this case highlights a new clinical presentation of nail erythrasma as melanonychia.
甲病可能反映多种局部和全身性皮肤病状况。某些甲部表现，如甲下黑素沉着，即便对于甲病专家而言也可能带来诊断挑战。我们报告一例78岁男性，其大脚趾出现甲下黑素沉着。指甲剪取物显示局灶性黑色素沉积，皮肤镜检查显示甲半月有局部红斑区域，怀疑可能为黑素细胞肿瘤。随后的指甲活检显示甲板内有大量垂直排列的丝状细菌和球杆菌，符合甲下红癣的诊断。甲下红癣是一种罕见病症。此外，该病例突出了甲下红癣一种新的临床表现，即甲下黑素沉着。
