Pre-auricular tags and pits in the newborn: the role of renal ultrasonography.

Abstract

To determine the role of renal ultrasonography in the evaluation of healthy newborn infants with isolated pre-auricular tags and pits. During the 4 years of prospective study, 108 of 17,286 infants were born with isolated pre-auricular tags or pits (6.2 per 1000 live births): 92 were assessed for urinary tract abnormalities by performing renal ultrasonography at 1 to 3 months of age. The study group was compared with a control group of 95 consecutive healthy infants without pre-auricular tags or pits born during the same period who underwent renal ultrasonography on the second day of life. The study and control groups were comparable in birth weight, gestational age, and sex ratio. Renal ultrasonography was abnormal only in 2 infants with pre-auricular tags (2.2%); both had mild left pyelectasis. The prevalence did not differ significantly from that in the control group, in which 3 infants had mild pyelectasis (3.1%, P = 1.0) and 1 infant had a renal calculus. The prevalence of renal abnormalities in infants with isolated pre-auricular tags or pits in our study (2.2%) was also comparable to the prevalence in the general population (all abnormalities 0.2%-8.1%; significant abnormalities 0.2%-1.4%). We conclude that renal ultrasonography is not indicated in the routine evaluation of the newborn infant with isolated pre-auricular tags or pits.