Studies on the relationship between esophageal acid exposure, mucosal lesions and heartburn using an acid exposure sensor.
BACKGROUND
In vitro studies of a recently developed acid exposure sensor show that the sensor response (SR) to acid <pH 4 is linearly determined by the duration and degree of acidity. The aim was to determine whether SR correlates with the severity of acid-induced esophageal mucosal lesions and acid-induced heartburn.


METHODS
HCl pH 1.5 or saline was infused into the feline esophagus for 5-20 min. Simultaneously, sensor measurements were performed below the infusion port. The histological damage was scored by an independent pathologist. In 15 normal subjects, HCl pH 1 was infused into the esophagus and the severity of the heartburn (0-5) was scored at 5-min intervals. In 10 subjects who experienced heartburn during acid perfusion, initial perfusion with HCl was repeated during heartburn induction time minus 5 min, followed by perfusion with the subject's own gastric juice, titrated to pH 2; heartburn severity was again scored at 5-min intervals. Acid exposure sensors positioned below the infusion port were removed at heartburn scores 1, 2 and 3.


RESULTS
A good correlation was found between SR and the histological score for mucosal damage in the cat esophagus (r = 0.64, P < 0.005). There was a good relation between heartburn severity score and acid exposure time (r = 0.84, P < 0.001), and a significant but weaker relation between heartburn severity and SR.


CONCLUSIONS
In cats, there is a good relation between the severity of acid-induced esophageal mucosal lesions and SR. In men, there is a significant correlation between the severity of acid-induced heartburn and the simultaneously measured SR. Therefore, SR measurement has the potential of yielding clinically relevant information in the investigation of GERD.
Vantrappen
G
G
Center for Gastroenterological Research and Dept. of Pathology, University Hospital Gasthuisberg and Interuniversity Micro Electronics Centre, University of Leuven, Leuven, Belgium. sonia.smets@uz.kuleuven.ac.be
Tack
J
J
Huyberechts
G
G
Sifrim
D
D
Geboes
K
K
Janmsens
J
J
Van Overstraeten
R
R
D000328:Adult; D000818:Animals; D002415:Cats; D003938:Diagnostic Techniques, Digestive System / Q000295:instrumentation; D004935:Esophageal Diseases / Q000139:chemically induced* / Q000473:pathology*; D004947:Esophagus / Q000473:pathology*; D005260:Female; D005744:Gastric Acid / Q000502:physiology; D005764:Gastroesophageal Reflux; D006356:Heartburn / Q000139:chemically induced* / Q000473:pathology*; D006801:Humans; D006851:Hydrochloric Acid / Q000009:adverse effects*; D006863:Hydrogen-Ion Concentration; D008297:Male; D023421:Models, Animal; D009092:Mucous Membrane / Q000473:pathology
D006851:Hydrochloric Acid