Background: The role of combined multichannel intraluminal impedance and pH monitoring (MII-pH) in diagnosing sliding hiatal hernia in gastroesophageal reflux disease (GERD) children remains unclear. We aimed to explore the clinical efficacy of MII-pH as a supplement diagnostic method for sliding hiatal hernia.
Methods: A total of 104 symptomatic GERD children [mean ± standard deviation (SD) age = 4.5 ± 5.5 years] were recruited. All of them were diagnosed as GERD with and without sliding hiatal hernia by barium and/or esophagogastroduodenoscopy study. All subjects received 24 h MII-pH monitoring to test the efficacy of this new modality.
Results: Sixteen children were diagnosed to have sliding hiatal hernia, and nine (56.3%) of them received fundoplication. None of non-hiatal hernia children were indicated for fundoplication [risk difference (RD) 0.56; P < 0.001]. Impedance probes detected more reflux episodes than pH-probe in the whole study population (mean ± SD = 62.1 ± 47.8 vs. 47.8 ± 48.1 episodes; P = 0.02, paired t test). Due to the presence of pH-only reflux, the reflux episodes detected by impedance probes is less than that by pH probe in sliding hiatal hernia children (mean ± SD = 49.2 ± 78.9 vs. 103.7 ± 60.4 episodes; P = 0.01, paired t test). Ratio of reflux episodes detected by pH-probe to that by impedance probes >1 was more frequently noted in sliding hiatal hernia children than non-sliding hiatal hernia children (Odds ratio 58.33, P < 0.001). The sensitivity and specificity of this diagnostic tool to predict sliding hiatal hernia in GERD children are 93.8 and 79.6%, respectively.
Conclusions: Ratio of reflux episodes detected by pH-probe to that by impedance probes >1 demonstrated by MII-pH study is a good screening test of sliding hiatal hernia in GERD children.