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Systematic review for paediatric metachronous contralateral inguinal hernia: a decreasing concern
Ramesh M Nataraja1, Anies A Mahomed
1Department of Paediatric Surgery, Royal Alexandra Hospital for Sick Children, Brighton, UK. nataraja@doctors.org.uk
Insights
Routine contralateral exploration for pediatric unilateral inguinal hernias is not supported by evidence. Infants under 6 months and those with left-sided hernias have higher risks of metachronous contralateral inguinal hernia (MCIH).
Area of Science:
- Pediatric Surgery
- Hernia Repair
- Clinical Evidence Synthesis
Background:
- Unilateral inguinal hernias in children often raise concerns about developing a metachronous contralateral inguinal hernia (MCIH).
- This potential for a second surgery necessitates evaluating the benefits of routine contralateral exploration.
Purpose of the Study:
- To systematically review current evidence on routine contralateral exploration for pediatric unilateral inguinal hernias.
- To identify specific patient groups at higher risk for MCIH.
Main Methods:
- A comprehensive literature review was conducted using broad search terms.
- Inclusion criteria focused on studies of pediatric unilateral inguinal hernia repair without routine contralateral exploration.
- Statistical analysis included Chi-square tests and calculation of numbers needed to treat (NNT).
Main Results:
- Data from 61 studies involving 49,568 patients showed an overall MCIH risk of 5.76%.
- The NNT to prevent one MCIH through contralateral exploration is 18.
- Increased MCIH risk was observed in patients under 6 months (NNT 9) and those with left-sided hernias (NNT 9).
Conclusions:
- Insufficient evidence supports routine contralateral inguinal exploration for all pediatric unilateral inguinal hernias.
- Consideration for contralateral exploration should involve parental discussion for infants <6 months and those with left-sided hernias, weighing potential benefits against risks.
Purpose:
Controversy still surrounds the treatment of the asymptomatic inguinal region in paediatric patients with a unilateral inguinal hernia. The concern is the development of a future metachronous contralateral inguinal hernia (MCIH) and therefore the need for a second operation. Our aim was to provide a current systematic review of the evidence for routine contralateral exploration, and identify potential at-risk groups.
Methods:
Comprehensive review of the literature utilising broad search terms to identify all relevant publications. Precise inclusion and exclusion criteria to identify studies that included paediatric unilateral inguinal hernia repair without routine contralateral exploration.
Data Analysis:
Chi-square with Yates' correction or a Fisher's exact test as appropriate. Numbers needed to treat (NNT) calculated with 95% confidence intervals.
Results:
A total of 7,130 titles and abstracts were screened and 61 studies included with data on 49,568 paediatric patients with a unilateral inguinal hernia fulfilling the inclusion criteria. 2,857 of these patients later developed a MCIH, revealing an overall risk is 5.76% (95% CI: 5.55-5.97%). The NNT for a MCIH is 18 (95% CI: 16.8-18) with 18 contralateral exploration required for the prevention of one MCIH. Patients <6 months at the time of the initial intervention were more likely to develop a MCIH; 183/1,470 (<6/12) versus 144/2,044 (≥6/12), P < 0.0001. As were patients with an original left-sided hernia; 815/6,739 versus 865/12,615, P < 0.0001. The NNTs for both of these groups were 9. There was no association with the gender of the patient; 888/14,480 (♂) versus 268/4,206 (♀), P = 0.37.
Conclusions:
There is insufficient evidence to support the routine contralateral inguinal exploration in all paediatric patients presenting with a unilateral inguinal hernia. However, with patients presenting with an originally left-sided hernia or who are less than 6 months old, a parental discussion should occur about the possible benefits and risks of contralateral exploration.
