title: Pathogenesis of proton-pump inhibitor-refractory non-erosive reflux disease according to multichannel intraluminal impedance-pH monitoring.
abstract: OBJECTIVE
  Proton-pump inhibitor (PPI) therapy is the first-line treatment for gastroesophageal reflux disease; however, there are some reports of PPI failure in cases of non-erosive reflux disease (NERD). Among the pathogenic factors associated with PPI-refractory NERD, reflux other than acid reflux can not be detected by conventional pH monitoring. The purpose of this study was to clarify the usefulness of multichannel intraluminal impedance-pH (MII-pH) monitoring for PPI-refractory NERD patients and examine the pathogenesis.
  
  
  METHODS
  We used MII-pH monitoring to examine 29 PPI-refractory NERD patients on PPI treatment. Reflux parameters, symptom index (SI: positive if ≥ 50%), and proximal migration were analyzed. The acidity of the reflux was divided into acid (nadir pH ≤ 4) and non-acid (nadir pH > 4). Subjects were classified into reflux-related disease (abnormal reflux parameters or positive SI) and non-reflux-related disease (normal reflux parameters and negative SI).
  
  
  RESULTS
  Of the 29 subjects, 21 were diagnosed with reflux-related disease, including 6 with acid reflux type and 15 with non-acid reflux type, and 8 were diagnosed with non-reflux-related disease. Of the total 1816 liquid reflux episodes, 834 showed proximal migration, which was more common in symptomatic reflux than in asymptomatic reflux.
  
  
  CONCLUSIONS
  MII-pH monitoring could distinguish reflux-related disease (especially non-acid type) from PPI-refractory NERD. Proximal migration was associated with symptomatic reflux in PPI-refractory NERD patients.
authors.affiliation: Department of Gastroenterology, Osaka City University Graduate School of Medicine, Osaka, Japan. yuki1215@med.osaka-cu.ac.jp
authors.forename: Yukie
authors.initials: Y
authors.lastname: Kohata
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Machida
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Okazaki
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Yamagami
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tanigawa
authors.forename: Kenji
authors.initials: K
authors.lastname: Watanabe
authors.forename: Toshio
authors.initials: T
authors.lastname: Watanabe
authors.forename: Kazunari
authors.initials: K
authors.lastname: Tominaga
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Arakawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D004351:Drug Resistance; D017097:Electric Impedance; D016099:Endoscopy, Gastrointestinal; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007564:Japan; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D012307:Risk Factors; D013997:Time Factors; D017211:Treatment Failure
chemical_list: D054328:Proton Pump Inhibitors