Association of isolated preauricular tags and nephrourological anomalies: case-control study.

Isolated preauricular tags (IPT) are considered minor malformations whereas nephrourological anomalies (NUA) are considered major malformations. Their incidences fluctuate between 5 and 10 per 1,000 and 1-3 per 100 live births, respectively. There is contradictory evidence regarding the incidence of NUA in infants with IPT.