title: Use of pH-impedance testing to evaluate patients with suspected extraesophageal manifestations of gastroesophageal reflux disease.
abstract: OBJECTIVE
  To report the use of pH-impedance testing in evaluating patients with suspected gastroesophageal reflux disease (GERD) with atypical symptoms.
  
  
  BACKGROUND
  Although the role of acid reflux in causing atypical GERD symptoms is generally accepted, the role, if any, of nonacid reflux is controversial, largely because until recently it has not been possible to detect nonacid reflux. The advent of intraluminal combined pH impedance testing (MII-pH), to detect nonacid reflux has heightened interest in its possible contribution to atypical symptoms.
  
  
  METHODS
  Fifty consecutive patients referred for MII-pH testing to evaluate the cause of atypical symptoms presumed due to GERD were evaluated. The symptoms were either refractory to acid inhibition therapy or so atypical that further work up was desired by the referring physician. Patients underwent MII-pH testing to determine whether reflux was present, and, if so, if it was due to acid, nonacid, or gas.
  
  
  RESULTS
  Only 16%, 22%, and 2% patients were found to have symptoms due to acid reflux, nonacid reflux, or both, respectively. Ten percent of these patients had gas reflux. MII-pH testing was useful in redirecting the management of patients who did not have reflux as the cause of their symptoms.
  
  
  CONCLUSIONS
  MII-pH testing is useful in determining whether gastroesophageal reflux is present in patients with atypical symptoms that have not responded to proton pump inhibitor therapy. It also distinguishes between reflux due to acid, nonacid, and gas, with consequences for management.
authors.affiliation: Department of Medicine, University of Connecticut Health Center, MC-1111, 263 Farmington Avenue, Farmington, CT-06030, USA. ashmalhotra@yahoo.com
authors.forename: Ashish
authors.initials: A
authors.lastname: Malhotra
authors.forename: James W
authors.initials: JW
authors.lastname: Freston
authors.forename: Khalid
authors.initials: K
authors.lastname: Aziz
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D017097:Electric Impedance; D050782:Esophageal pH Monitoring / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D005744:Gastric Acid / Q000378:metabolism*; D005764:Gastroesophageal Reflux / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D007827:Laryngitis / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010612:Pharyngitis / Q000175:diagnosis* / Q000209:etiology; D011014:Pneumonia / Q000175:diagnosis* / Q000209:etiology; D011379:Prognosis