Evidence-based change of practice in the management of unilateral inguinal hernia.

PURPOSE: Contralateral inguinal exploration in children with unilateral inguinal hernia is still controversial. Only 20% of patients with patent processus vaginalis would develop a clinically apparent hernia [Miltenburg DM, Nutctern JG, Jaksic Tkozinetz CA. Meta-analysis of the risk of metachronous hernia in infants and children. Am J Surg 1997;174:741-4]. In 1999, our unit changed the practice of performing routine contralateral inguinal exploration of male children younger than 2 years and female children younger than 5 years to inguinal herniotomy of the symptomatic side only based on a meta-analysis published by Miltenburg et al [Meta-analysis of the risk of metachronous hernia in infants and children. Am J Surg 1997;174:741-4]. We explored the contralateral inguinal area only in babies with a history of prematurity.

METHODS: A prospective study of patients subjected to unilateral inguinal herniotomy from 1999 to 2001 was performed. Age, sex, side of the hernia, and incarceration at presentation were recorded. The incidence of metachronous inguinal hernia (MIH) and its risk factors were analyzed. The follow-up ranged from 36 to 72 months.

RESULTS: Of the 409 patients who presented with inguinal hernia, 264 underwent unilateral inguinal herniotomy. The rest were either children with bilateral inguinal hernia or premature babies who were offered bilateral inguinal herniotomy. Of these 264 patients, 180 (68%) had right-sided inguinal hernia and 84 (32%) had left-sided inguinal hernia. Fourteen (5%) patients subsequently presented with MIH. Of these 14 patients, 8 were younger than 2 years at the initial presentation and 11 originally presented with left-sided inguinal hernia. No female child presented with MIH. Twelve (85%) re-presentations with MIH occurred within 1 year of the original operation.

CONCLUSIONS: The treatment of only the symptomatic inguinal hernia has not significantly increased the incidence of MIH. This evidence-based change of practice has avoided 152 operations in 264 patients. Presentation with incarceration and age at presentation have no significant impact on the incidence of MIH. Left-sided presentation has a statistically significant high incidence of MIH.