Youn S H, Kwon O S, Park K C, Youn J I, Chung J H
Department of Dermatology, Seoul National University College of Medicine, Korea.
Clin Exp Dermatol. 1996 Nov;21(6):457-8. doi: 10.1111/j.1365-2230.1996.tb00157.x.
We report a case of congenital onychodysplasia of the index fingers (Iso-Kikuchi syndrome) in a 2-year-old boy who had nail deformities on both index fingers and the left second toe. He had a micronychia of the left index fingernail, malalignment and abnormal lunula of the right index fingernail and micronychia and malalignment of the left second toenail. Congenital onychodysplasia of the index fingers (COIF) is a rare condition characterized by various forms of nail dysplasia commonly involving the index fingers, but not infrequently also the neighbouring fingers such as the middle fingers and thumbs. The five criteria characterizing COIF include the following: (i) congenital occurrence; (ii) unilateral or bilateral index finger involvement; (iii) variability in nail appearance; (iv)possible hereditary involvement; and (v) frequently associated bone abnormalities. The nails of COIF include the full spectrum of nail dysplasia, from an irregular lunula, malalignment, micronychia (hypoplastic and rudimental), polyonychia (split rudimental), and anonychia, specifically affecting the index fingers. Our patient represents various forms of nail dysplasia of the both index fingers and left second toe such as micronychia, malalignment and abnormal lunula. To our knowledge, the association with second toenail dysplasia in COIF has not previously been reported.
我们报告了一例2岁男孩的先天性食指甲发育异常（矶崎症候群），该男孩双侧食指及左足第二趾均有指甲畸形。他的左食指指甲过小，右食指指甲排列不齐且甲半月异常，左足第二趾指甲过小且排列不齐。先天性食指甲发育异常（COIF）是一种罕见病症，其特征为多种形式的指甲发育异常，通常累及食指，但也常累及相邻手指，如中指和拇指。COIF的五个特征标准如下：（i）先天性发病；（ii）单侧或双侧食指受累；（iii）指甲外观多变；（iv）可能存在遗传因素；（v）常伴有骨骼异常。COIF的指甲包括指甲发育异常的全谱，从不规则甲半月、排列不齐、指甲过小（发育不全和残留）、多指（分裂残留）和无甲，特别影响食指。我们的患者双侧食指及左足第二趾呈现出多种形式的指甲发育异常，如指甲过小、排列不齐和甲半月异常。据我们所知，此前尚未报道过COIF与第二趾甲发育异常的关联。
