Prospective evaluation of the diagnostic yield and tolerance of high-resolution manometry, pH-impedance and pH-impedance-manometry

Objectives: We prospectively evaluated the interpretability, diagnostic yield, and tolerance of high-resolution (impedance-) manometry, 24 h-pH-impedance and pH-MII with manometry (two catheters) in children. Methods: All children who underwent testing were eligible. We assessed whether the results explained the patients' symptoms (interpretability) and recorded the diagnostic yield of each test. A validated questionnaire (DISCOmfort in Research with Children [DISCO-RC]) was additionally used to measure discomfort during the procedures. Results: Forty-nine HR(I)M, 35 pH-MII, and 9 pH-MII + mano were performed in 62 children (median age: 13 [0–18] years). Nine (25%) pH-MII catheters were placed under sedation during another procedure. Seven (7.4%) tests (five h(I)M and two pH-MII) were uninterpretable. All normal tests were considered clinically helpful by the attending physician. Sixty-nine (74.2%) tests in 58 patients (93.5%) led to clinical management that would likely not have occurred without testing. DISCO-RC scores were 7.0 (1–17), 6.0 (01–19), and 14.0 [9–17] in HR(I)M, pH-MII, and pH-MII + mano, respectively. DISCO-RC scores were significantly higher in pH-MII + mano (p = 0.033 and p = 0.005) compared to HR(I)M and pH-MII respectively. Conclusion: HR(I)M, pH-MII, and pH-MII + mano are interpretable and clinically useful in most children. HR(I)M and pH-MII are reasonably well tolerated, whereas adding ambulatory manometry causes more discomfort and should be reserved for cases where the diagnosis of rumination cannot be made without it.