title: The acid pocket: a target for treatment in reflux disease?
abstract: The nadir esophageal pH of reflux observed during pH monitoring in the postprandial period is often more acidic than the concomitant intragastric pH. This paradox prompted the discovery of the "acid pocket", an area of unbuffered gastric acid that accumulates in the proximal stomach after meals and serves as the reservoir for acid reflux in healthy individuals and gastroesophageal reflux disease (GERD) patients. However, there are differentiating features between these populations in the size and position of the acid pocket, with GERD patients predisposed to upward migration of the proximal margin onto the esophageal mucosa, particularly when supine. This upward migration of acid, sometimes referred to as an "acid film", likely contributes to mucosal pathology in the region of the squamocolumnar junction. Furthermore, movement of the acid pocket itself to a supradiaphragmatic location with hiatus hernia increases the propensity for acid reflux by all conventional mechanisms. Consequently, the acid pocket is an attractive target for GERD therapy. It may be targeted in a global way with proton pump inhibitors that attenuate acid pocket development, or with alginate/antacid combinations that colocalize with the acid pocket and displace it distally, thereby demonstrating the potential for selective targeting of the acid pocket in GERD.
authors: Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA. p-kahrilas@northwestern.edu
authors: Peter J
authors: PJ
authors: Kahrilas
authors: Kenneth
authors: K
authors: McColl
authors: Mark
authors: M
authors: Fox
authors: Lisa
authors: L
authors: O'Rourke
authors: Daniel
authors: D
authors: Sifrim
authors: Andre J P M
authors: AJ
authors: Smout
authors: Guy
authors: G
authors: Boeckxstaens
mesh_terms: D000464:Alginates / Q000627:therapeutic use; D000863:Antacids / Q000627:therapeutic use; D004943:Esophagogastric Junction; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism*; D006551:Hernia, Hiatal / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D019518:Postprandial Period; D054328:Proton Pump Inhibitors / Q000627:therapeutic use
chemical_list: D000464:Alginates; D000863:Antacids; D054328:Proton Pump Inhibitors