A long-term prospective analysis of pediatric unilateral inguinal hernias: should laparoscopy or anything else influence the management of the contralateral side?

PURPOSE: To prospectively determine if children who present with a unilateral inguinal hernia can be identified as at risk for developing a metachronous inguinal hernia (MIH) based on risk factors and laparoscopic findings of the contralateral internal ring.
MATERIALS AND METHODS: Between April 2000 and October 2004, 299 patients with a unilateral inguinal hernia were followed prospectively. Laparoscopy was attempted in each child. Bilateral repair was only performed in those with contralateral swelling or crepitus during laparoscopic evaluation. All other children were followed regardless of laparoscopic findings. Risk factors to include premature delivery, family history and increased abdominal pressure were recorded. Clinical follow up and annual phone interviews were performed to determine the development of a MIH.
RESULTS: Thirteen patients underwent initial bilateral inguinal hernia repair. Of the remaining 286 patients (272 boys, 14 girls; ages 54+/-50.8 months), laparoscopy revealed 127 closed, 48 cleft and 67 open (contralateral patent processus vaginalis) contralateral internal rings, and in 44 laparoscopy was not possible due to a small hernia. Of 222 patients followed for 53.2 months (30.1-82.5 months), 15 (6.8%) developed a MIH. When comparing age, gender, laterality, laparoscopic findings, family history, premature birth and intra-abdominal pressure, only family history exhibited a significant risk for MIH (33% vs 7.7%). However, 16/21 children with a family history never developed a MIH, and 47/53 children with a contralateral patent processus vaginalis have yet to develop one.
CONCLUSIONS: Risk factors and laparoscopic findings failed to predict the few children who would develop a MIH. The contralateral side should not be routinely explored by any methodology.