Ingestion of Acidic Foods Mimics Gastroesophageal Reflux During pH Monitoring

Abstract

Ingestion of acidic foods may produce artifactual drops in pH to < 4 that may be difficult to differentiate from a true acid reflux event. We aimed to evaluate intraesophageal pH changes during the ingestion of acidic food and describe the frequency and implications of acidic food ingestion on ambulatory pH monitoring. Ten normal volunteers (six females; mean age, 34) underwent combined impedance-pH testing with a pH electrode placed 5 cm above the lower esophageal sphincter. Each volunteer received 50 ml each of acidic foods in random order. Nadir and mean pH for 30 sec after ingestion of each substance were recorded. Subsequently 100 randomly selected reflux monitor diaries were reviewed, searching for ingestion of acidic foods, and 100 pH tracings were reviewed to evaluate the impact of including/excluding meal periods on percentage time pH < 4 and DeMeester scores. All foods produced abrupt drops to pH < 4, in 80% of cases exceeding 30 sec. During ambulatory pH monitoring 78% of patients recorded ingestion of at least 1 of the 10 tested substances during meals, the majority admitting ingesting carbonated beverages. Not excluding meal periods would have led to the misinterpretation of 6-16% of tracings, depending on the criteria used to identify abnormal acid exposure. We conclude that ingestion of acidic foods is frequent and carries the risk of overdiagnosing GERD. Current findings support the recommendations to carefully instruct patients to record all oral intake and to exclude meal periods from the analysis.

Normal values in ambulatory oesophageal pH monitoring at two levels in Spain

“…The acidity of certain foodstuffs may affect oesophageal pH recording by overestimating the number of reflux episodes (15,16), but its real impact is small (1,9,17,18). Our results support the limited role of meals on distal reflux: including or excluding the meal periods made little difference at distal level (Table I).…”

Diagnosis and Treatment of Gastroesophageal Reflux Disease

“…Another advantage of wireless capsule is the fixed position of the capsule on the esophageal wall in comparison to catheter-based systems where migration due to swallowing or talking has been shown to occur [14,15] . Potential disadvantages include additional expense due to endoscopic placement (as nasal passage can be difficult due to size of capsule), early detachment in a minority of patients, patient discomfort which could require removal via repeat endoscopy, as well as overdiagnosis of GERD due to ingestion of acidic foods [16] . There is also some data suggesting an increased number of reflux episodes during the first 6 hour period following propofol administration [17] .…”

Quality evaluation and estimation of shelf life of retort-pouched tomato-based and Korean traditional fermented food-based sauces

“…Ketchup has a pH of approximately 4 (Eribo and Ashenafi 2003;Agrawal et al 2005;Islam et al 2006). In a study by Yun et al (2007), they found that preservation of some low-pH products, such as meat extract solution, watery Kimchi solution, and soy sauce/vinegar mixes, may be related to their low pH.…”