PEDIATRIC UROLOGY

A long-term prospective analysis of pediatric unilateral inguinal hernias: should laparoscopy or anything else influence the management of the contralateral side?
Maddox MM, Smith DP
East Tennessee Children’s Hospital, Knoxville, TN, USA
J Pediatr Urol. 2008; 4: 141-5

• 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.
  
  
• Editorial Comment
  This manuscript studied the questions of whether laparoscopy or any other diagnostic treatment modality should be used to evaluate the contralateral inguinal canal for hernia development. These authors studied 299 patients prospectively over about 4 years and inguinal herniorrhaphies on the contralateral side were only performed if the child demonstrated an inguinal swelling or during laparoscopy palpable crepitans. The laparoscopic exam of the contralateral internal ring was divided into three categories: closed, cleft or open.
  Thirteen of their initial patients underwent surgery at the same time on the contralateral groin because of inguinal swelling or crepitance at the time of laparoscopy. 23% of the patients had a contralateral patent processus vaginalis. 44% were closed and 17% had a cleft and 15% did not undergo laparoscopic evaluation because of technical issues. After 19 months, 9 patients (3.6%) had developed a contralateral inguinal hernia, and after a minimum of 30 months, 6 more children had developed an inguinal hernia on the opposite side for a 6.8% rate. There were no predictive factors in the history or physical exam that were helpful, except a positive family history.
  In this study a contralateral patent processus vaginalis only predicted 11% of patients that went on to develop an inguinal hernia. The manuscript did not show any age factors as predictive indicators and this group of patients did not show a laterality difference. The authors conclude that the contralateral side should not routinely be explored by any method.
  For years, what to do with the opposite inguinal canal when a clinical hernia is present has been studied and debated. This manuscript and references cited within it seem to suggest that there is no reason to explore an asymptomatic inguinal canal, nor is there a reason to look at it laparoscopically. With only a 7% metachronous hernia rate, many unnecessary procedures can be avoided.

Dr. Brent W. Snow
Division of Urology
University of Utah Health Sci Ctr
Salt Lake City, Utah, USA
E-mail: brent.snow@hsc.utah.edu