Iso-Kikuchi Syndrome: Report of 3 Pediatric Cases.

Iso-Kikuchi syndrome, or congenital onychodysplasia of the index finger, is an uncommon condition characterized by total anonychia or dysplasia of the nail of the index finger. It is occasionally accompanied by underlying bone abnormalities and is rarely associated with other conditions. Although various hypotheses have been put forward to explain the pathophysiology of the syndrome, its etiology remains unknown. We report the cases of 3 pediatric patients (2 boys and 1 girl) with nail changes and bone abnormalities consistent with Iso-Kikuchi syndrome. We highlight the importance of recognizing this entity early to avoid the need for additional tests and unnecessary treatment.