Reflux symptoms are among the most common complaints seen in family practice. Careful diagnosis is essential to initiate rapid treatment and prevent worse.
Symptomatic reflux is highly prevalent: between 10-30% of the population in industrialized countries is affected. Complications of reflux disease can include reflux esophagitis, stenosis, or even esophageal cancer. This makes precise diagnosis all the more important in order to treat reflux quickly. At the Cancer Academy, Daniel Pohl, MD, Senior Physician, Functional Diagnostics at the University Hospital Zurich, explained which diagnostic tools can be used to correctly assess symptoms.
Highly specific, but not very sensitive: GerdQ
Reflux typically manifests as heartburn, acid regurgitation and regurgitation. In addition, there are other non-specific symptoms that must be recorded as part of a detailed medical history (tab. 1). The frequency and temporal distribution of the symptoms are also diagnostically important. If symptoms occur at least once or twice a week, reflux disease is likely. Because many medications can trigger reflux, a medication history is also important.
In theory, the GerdQ (“Gastroesophageal Reflux Disease Questionnaire”) – a questionnaire with six questions about reflux symptoms, their severity and frequency – enables a cost-effective and rapid diagnosis. A Chinese study subjected the GerdQ to a real world test. For this purpose, 8000 patients from 122 centers were surveyed using the GerdQ and the results were compared with the results of the subsequently performed gastroscopies. Conclusion: The GerdQ was able to diagnose reflux disease with a high degree of certainty at scores >8. But the lower the score, the less sensitive the GerdQ. Although the study showed a correlation between the score and the number of patients with reflux esophagitis, the questionnaire could not ultimately exclude the disease: 22% of those found to be negative by questionnaire (with low symptom severity) had reflux esophagitis on gastroscopy. In a few, carcinoma was already present despite symptom absence and low GerdQ score [1]. Thus, although the GerdQ is suitable for clinical studies, it is not a reliable diagnostic tool.
How accurate is the PPI test?
If typical reflux symptoms but no alarm symptoms are present, proton pump inhibitors (PPI) can be given on a trial basis [2]. Empiric acid suppression is common in primary care practices. However, the results of a multicenter study examining the diagnostic accuracy of PPI testing in 308 primary care patients with reflux symptoms over a two-week period point to limited validity: although PPI testing was indeed positive in most patients with typical reflux symptoms. However, a significant proportion of those who did not respond to the test still had GERD. In patients not affected by GERD, the ratio of positive and negative tests was balanced. Thus, the PPI test is not a reliable indicator of GERD [3].
Means of choice: endoscopy and 24h-MIIpH
Not every patient with reflux symptoms should be endoscoped. The indication is given when alarm symptoms are present. These include dysphagia, weight loss, and anemia. “But alarm symptoms aren’t everything,” warns Dr. Pohl: “An Asian study found pathologic changes in 40% of an endoscopy of 469 patients with reflux symptoms without alarm symptoms. Most often, this was reflux esophagitis. In rare cases, gastric ulcers, chronic remodeling, or carcinoma already existed [4].
Initial endoscopy may also be helpful in treatment planning when morphologic sequelae of reflux are suspected or patient wishes are expressed. Rapid clarification improves patient satisfaction and compliance. If ERD is diagnosed during endoscopy, therapy can be started immediately; the severity of damage is defined by Los-Angeles classification. The differential diagnosis to eosinophilic esophagitis or Barrett’s esophagus is made by biopsy.
If no dangerous correlate is found and the symptoms persist despite PPI, functional diagnostic measures are indicated (Fig. 1).
The highest sensitivity and specificity here are 24-hour pH-metry and ph-metry-MII (MII=mulican intraluminal impedance measurement). Both also capture NERD patients and correlate symptoms with reflux episodes, allowing the patient to be tested for GERD even in the presence of atypical symptoms or PPI nonresponse. In particular, the guideline recommends ph-metry-MII [2]. This records both bolus movements and acid exposure in the esophagus. In combination with pH-metry, reflux events can be differentiated into acidic, weakly acidic (>pH 4 and <pH 7) and non-acidic (>pH 7) events [5]. The symptom correlation is crucial for differentiating NERD from hypersensitive esophagus and functional heartburn [6].
It is not always reflux
If neither clinic nor endoscopy confirms GERD and empiric PPI therapy does not lead to improvement of symptoms, it is reasonable to suspect that the symptoms are not caused by reflux. This is the case, for example, in patients with functional heartburn. Dysmotility or regurgitation may also manifest as heartburn. In addition to a detailed medical history, various tools can be used to determine the cause. For persistent acid or nonacid reflux, pressure measurement and 24-pH metry-MII with/without therapy are performed. Radiological procedures are used in pre- and postoperative diagnostics in the context of surgical reflux therapy, although they tend to be of secondary importance [6].
Source: Cancer Adacemy Zurich
Literature:
- Bai Y, et al: Gastroesophageal reflux disease questionnaire (GerdQ) in real-world practice: a national multicenter survey on 8065 patients. J Gastroenterol Hepatol 2013; 28(4): 626-631.
- Koop H, et al: Gastroesophageal reflux disease. S2k guideline, version 14 June 2014. www.awmf.org/leitlinien/detail/ll/021-013.html, last accessed 14 May 2019.
- Bytzer P, et al: Limited ability of the proton-pump inhibitor test to identify patients with gastroesophageal reflux disease. Clin Gastroenterol Hepatol 2012; 10(12): 1360-1366.
- Peng S, et al: Prompt upper endoscopy is an appropriate initial management in uninvestigated chinese patients with typical reflux symptoms. Am J Gastroenterol 2010; 105(9): 1947-1952.
- Savarino E, et al: Characteristics of reflux episodes and symptom association in patients with erosive esophagitis and nonerosive reflux disease: study using combined impedance-pH off therapy. Am J Gastroenterol 2010; 105(5): 1053-1061.
- Bittinger M, et al: S2k guideline gastroesophageal reflux disease. Bayrisches Ärzteblatt 2015; 10: 488-495.
HAUSARZT PRAXIS 2019; 14(6): 30-31 (published 5/24/19, ahead of print).
