Assessing the Reliability of 12- vs 24-Hour Esophageal pH-Impedance Monitoring for Gastroesophageal Reflux in Infants

INTRODUCTION: – The recommended duration of esophageal multichannel intraluminal impedance pH (MII-pH) monitoring to detect gastroesophageal reflux (GER) is currently 24 hours. This prolonged recording can be challenging in certain circumstances. We aimed to assess the diagnostic reliability of 12- vs 24-hour MII-pH in infants.METHODS: – Retrospective multicenter study assessing MII-pH tracings from infants referred for suspect gastroesophageal reflux disease (GERD). Each MII-pH was analyzed twice as full-time recording and in the first 12 hours, and data were compared. GERD was diagnosed if one of the following occurred: number of GER episodes ≥100 in 24 hours, proximal GER episodes >44 (acid) or 57 (nonacid), reflux index (percent time with pH < 4) >7%, Bolus Exposure Index >2.4%, Bolus Clearance Time >18 seconds, Symptom index ≥50%, and Symptom Association Probability ≥95%. Univariate analysis was performed to compare MII-pH data.RESULTS: – One hundred twenty-seven infants were studied. The median age at MII-pH was 61 days (interquartile range-IQR 27–116), and 49 were born preterm. There were no significant differences between the 12- and the 24-hour analysis regarding the number of total GER and proximal GER events/hr, reflux index, Bolus Exposure Index, Bolus Clearance Time, positive Symptom index/Symptom Association Probability. GER events lasting >5 min/hr were 1.97 ± 0.27 and 1.83 ± 0.44, respectively (P < 0.001). The 12-hour MII-pH recording showed 87.7% sensitivity, 75.6% specificity, 89.7% positive predictive value, and 71.7% negative predictive value for GERD compared with 24-hour MII-pH.DISCUSSION: – Twelve-hour MII-pH had a good diagnostic performance compared with 24-hour recording. Only GER events lasting >5 minutes were significantly different between the 2, but the clinical significance of this observation is unclear.