Risk factors for metachronous contralateral inguinal hernia after laparoscopic percutaneous extraperitoneal closure for unilateral inguinal hernia in children.

Purposes: We use the laparoscopic percutaneous extraperitoneal closure (LPEC) method as the standard procedure for pediatric inguinal hernia. Despite judging there to be no contralateral patent processus vaginalis (PPV) at the time of the first LPEC, we experienced five cases in which metachronous contralateral inguinal hernia (MCH) developed, so we report the characteristics, including the predictors.

Methods: For pediatric inguinal hernia, the LPEC method was used in 1277 cases from 2005 to 2019 in our department. Of these, 374 patients underwent unilateral LPEC, and we compared the 5 patients with MCH onset and the 369 without MCH onset. The items to be examined were the gender, age, presence of a low birth weight, initial-onset side, and contralateral internal inguinal ring classification.

Results: There was no significant difference in the gender, age, initial-onset side, or contralateral internal inguinal ring classification between the two groups. Low-birth-weight infants were significantly more common among those with MCH than among those without MCH.

Conclusions: The only predictor of a contralateral onset after LPEC for pediatric inguinal hernia was a low birth weight. Therefore, for the above-mentioned unilateral LPEC cases, the possibility of a contralateral onset after LPEC due to acquired factors rather than congenital factors should be considered.