REPRODUCIBILITY OF 24-HOUR INTRAESOPHAGEAL PH MONITORING IN PEDIATRIC-PATIENTS

Objective. Despite the widespread use of 24-hour intraesophageal pH mo nitoring for evaluation of gastroesophageal reflux in infants and chil dren, there is little published information regarding the reproducibil ity of ambulatory pH studies in this patient population. The purpose o f our study was to evaluate the reproducibility of 24-hour intraesopha geal pH monitoring in pediatric patients. Methods. We prospectively in vestigated 26 patients with symptoms suggestive of gastroesophageal re flux (14 females and 12 males) ranging in age from 1 month to 18 years (mean, 9.2 years). The patients underwent extended intraesophageal pH monitoring over two consecutive 24-hour periods. Results. Data analys is revealed that the overall reproducibility of ambulatory 24-hour pH monitoring is only 69% (r = 0.32). Eight of 26 patients had conflictin g results on day 1 compared with results on day 2. Of the 8 patients w ith conflicting results on day 1 versus day 2, 5 had normal studies on day 1, but demonstrated pathologic reflux on day 2. Thus, the false-n egative rate for day 1 was 19.2%. The kappa statistic calculated for t he total time the pH was abnormal was 0.32, with values <0.4 represent ing poor correlation. Spearman correlation coefficients indicated that the percentage of time with pH <4 (r = 0.64) and the number of reflux episodes (r = 0.71) per 24-hour period are the most reproducible pH p arameters. Conclusion. The reproducibility of 24-hour intraesophageal pH monitoring in the pediatric population is suboptimal. The investiga tion should be extended or repeated if the result does not correlate w ith the patient's clinical history.