1īoth LPR and GERD can be evaluated by a variety of diagnostic tests, including barium esophagography, radionucleotide scanning, the Bernstein acid perfusion test, esophagoscopy with biopsy, impedence testing, and pH probe monitoring. Not only is esophageal motility generally different between LPR and GERD patients, but reflux patterns on pH probe studies demonstrate that LPR patients are more likely to have reflux in an upright position whereas GERD patients are more likely to reflux in a supine position.
This suggests that differences in pathophysiology between LPR and GERD patients are part of the basis for the contrasting symptomology. 2 In addition, the difference in acid clearance between LPR patients and normal individuals was not statistically significantly different. In one study, esophageal acid clearance time was significantly longer in patients with GERD (isolated or in combination with LPR) than in patients with isolated LPR.
6 In contrast, the same study demonstrated that 89% of gastroenterology patients with reflux reported heartburn, and none of them complained of hoarseness.Įsophageal motor function has also been shown to differ between LPR and GERD patients. One landmark study demonstrated that 100% of otolaryngology patients with reflux complained of hoarseness, but only 6% of them reported heartburn. 4, 5 Patient complaints also differ from LPR to GERD patients. For example, obesity is not associated with isolated LPR however, it has a strong association with GERD and it is an independent risk factor for GERD symptoms and erosive esophagitis. Patient risk factor profiles and complaints differ greatly from LPR patients to GERD patients. 1, 2, 3, 4, 5, 6 Furthermore, the diagnostic modalities for the evaluation of LPR are different from those for GERD. Over recent decades, studies have shown LPR and GERD to be two unique but related disease entities, with different risk factors, symptoms, pathophysiology, and responses to therapy. Although these diagnostic criteria for GERD and LPR may vary across institutions, the contrasting pH probe criteria for LPR and GERD is a common theme, because laryngeal and pharyngeal mucosa are much more susceptible to acidic injury than esophageal mucosa.Īlthough some patients meet pH probe criteria for both GERD and LPR, many have LPR or GERD alone. In contrast, one or two episodes of acid exposure (pH <4) at the proximal probe located in or above the upper esophageal sphincter ( UES) is accepted as diagnostic of LPR. Esophageal acid exposure times below this are considered normal or physiologic esophageal reflux. Using prolonged pH monitoring, the diagnosis of gastroesophageal reflux disease ( GERD) is typically not made unless a patient exhibits over 45 reflux episodes or has elevated acid exposure times at the esophageal probe ( Table 1). Other synonyms that have been used for LPR include extraesophageal reflux, "atypical" reflux, gastropharyngeal reflux, laryngeal reflux, pharyngoesophageal reflux, and supraesophageal reflux. In some cases the gastric refluxate reaches the larynx or pharynx, which is called laryngopharyngeal reflux ( LPR). Gastroesophageal reflux involves the backflow of stomach contents into the esophagus.