Yield of 24-hour esophageal pH and bilitec monitoring in patients with persisting symptoms on PPI therapy

Dig Dis Sci. 2008 Sep;53(9):2387-93. doi: 10.1007/s10620-007-0186-6. Epub 2008 Mar 6.


Current management algorithms propose pH monitoring under proton pump inhibitors (PPIs) in suspected gastroesophageal reflux disease (GERD) with insufficient treatment response, but recent observations challenge this approach because of its low yield.

Aim: To perform an audit of the outcomes of pH monitoring under PPI therapy in our unit, and to study the yield of additional nonacid reflux monitoring.

Methods: All pH monitoring studies under antireflux therapy since 1997, with or without simultaneous Bilitec monitoring, were analyzed.

Results: From 1997 to 2003, 347 patients (157 men, mean age 49.4 +/- 0.8 years) underwent pH studies on PPI therapy (28% half-, 67% full-, and 5% double-dose PPI) for persisting typical (53%) or atypical (75%) symptoms. In 184 patients, simultaneous Bilitec monitoring was performed. Esophageal pH monitoring on PPI was pathological in 105 (30%) patients. Pathological pH monitoring on PPI was associated with typical reflux symptoms (64 versus 52%, P = 0.03), and a higher prevalence of persisting esophagitis (54 versus 36%, P < 0.005) and of hiatal hernia (58 versus 27%, P < 0.005). Bilitec monitoring on PPI therapy was pathological in 114 (62%) patients, of which 74 (40%) had normal pH monitoring. Adding Bilitec increased the rate of abnormal results over pH monitoring alone, from 38% to 69% on half-dose, from 27% to 69% on full-dose, and from 0% to 38% on double-dose PPI.

Conclusions: The rate of abnormal pH monitoring in symptomatic GERD patients while on PPI therapy is relatively low, especially in those on double-dose PPI. Combined pH and Bilitec monitoring significantly increased the rate of ongoing pathological reflux compared to pH alone in refractory to PPI therapy GERD patients.

MeSH terms

  • Circadian Rhythm / physiology*
  • Clinical Audit
  • Dose-Response Relationship, Drug
  • Esophageal pH Monitoring*
  • Female
  • Gastroesophageal Reflux / drug therapy*
  • Gastroesophageal Reflux / physiopathology*
  • Humans
  • Male
  • Middle Aged
  • Proton Pump Inhibitors / therapeutic use*
  • Retrospective Studies
  • Spectrophotometry*
  • Treatment Outcome


  • Proton Pump Inhibitors