Renal Ultrasound in Patients With Preauricular Skin Tags: Is It Necessary and Who Needs It?

<b>Introduction:</b> Congenital preauricular lesions, including skin tags, accessory tragi, and pits, have long been associated with renal anomalies due to their shared embryologic origin. Despite the common practice of recommending routine renal ultrasound screening for these patients, the necessity of this protocol has not been conclusively validated. <b>Methods:</b> A retrospective review was conducted at a single institution from 1996 to 2025. A total of 109 patients presenting with congenital preauricular lesions were identified. Data extracted included demographics, comorbidities, syndromic status, hearing assessments, external ear abnormalities, and renal imaging findings. Statistical analyses (chi-square, Fisher's exact test, and one-sample proportion z-tests) were employed to evaluate the prevalence of renal anomalies compared to the general population and explore associations with other clinical factors. <b>Results:</b> Of the 109 patients with congenital preauricular lesions, 69 underwent renal imaging, and 34.8% (24/69) were found to have abnormal findings, significantly higher (<i>P</i> = .0011) than the estimated 1.5% prevalence among the general US population. Hydronephrosis was the most frequent abnormality, while no significant differences emerged across syndromic versus nonsyndromic patients, external ear anomalies, or documented hearing loss. <b>Conclusion:</b> These findings indicate a higher-than-expected rate of renal pathology in patients with congenital preauricular lesions and support a low threshold for imaging regardless of syndromic status or other risk factors. Prospective research is needed to further refine screening recommendations.